From 09893c4eff7ef6572e6e2e8817aeb55771eba9bb Mon Sep 17 00:00:00 2001
From: Edward Betts <edward@4angle.com>
Date: Wed, 15 Feb 2017 14:59:18 +0000
Subject: [PATCH] add xanadoc viewer

---
 sourcing/edl.py                      |  138 +
 sourcing/parse.py                    |  173 +-
 sourcing/static/css/xanadoc.css      |  106 +
 sourcing/static/js/interact.js       | 5976 ++++++++++++++++++++++++++
 sourcing/static/js/viewer.js         |  397 ++
 sourcing/templates/head.html         |    1 +
 sourcing/templates/view.html         |    3 +
 sourcing/templates/view/xanadoc.html |   53 +
 sourcing/url.py                      |   45 +
 sourcing/view.py                     |   35 +-
 10 files changed, 6748 insertions(+), 179 deletions(-)
 create mode 100644 sourcing/edl.py
 create mode 100644 sourcing/static/css/xanadoc.css
 create mode 100644 sourcing/static/js/interact.js
 create mode 100644 sourcing/static/js/viewer.js
 create mode 100644 sourcing/templates/view/xanadoc.html
 create mode 100644 sourcing/url.py

diff --git a/sourcing/edl.py b/sourcing/edl.py
new file mode 100644
index 0000000..6a28075
--- /dev/null
+++ b/sourcing/edl.py
@@ -0,0 +1,138 @@
+from .url import get_url, get_text
+from .parse import get_span, parse_span, parse_link, parse_sourcedoc_facet, xanadoc_span_html, span_html, get_urls
+from collections import defaultdict
+from html import escape
+
+import re
+
+re_comment = re.compile(r'#.*')
+re_xanalink = re.compile('xanalink: +([^ ]+) *$')
+max_sourcedoc_size = 600000
+
+def fulfil_edl(edl):
+    text = {}
+    for url, start, length in parse_edl(edl):
+        if url not in text:
+            text[url] = get_text(url)
+
+        yield get_span(text, url, start, length)
+
+def parse_edl(edl_text):
+    edl = {
+        'spans': [],
+        'links': [],
+    }
+    for line in edl_text.splitlines():
+        line = re_comment.sub('', line).strip()
+        if not line:
+            continue
+        span_pointer = parse_span(line)
+        if span_pointer:
+            edl['spans'].append(span_pointer)
+            continue
+        m = re_xanalink.match(line)
+        if m:
+            link_url = m.group(1)
+            edl['links'].append({
+                'url': link_url,
+                'text': get_url(link_url),
+            })
+            continue
+
+    return edl
+
+def fulfil_edl_with_sources(edl_text):
+    edl = parse_edl(edl_text)
+    spans = edl['spans']
+
+    hide_transclusions = set()
+
+    two_facet_links = []
+
+    link_num = 0
+    for link in edl['links']:
+        link_detail = parse_link(link['text'])
+        if link_detail['type'] == 'HideTransclusions':
+            hide_transclusions.add(parse_sourcedoc_facet(link_detail['facets'][0]))
+        elif len(link_detail['facets']) == 2:
+            two_facet_links.append((link_num, [parse_span(span[0]) for span in link_detail['facets']]))
+            link_num += 1
+
+    source = [get_text(url) for url in get_urls(spans)]
+
+    source_text = {s['url']: s['text'] for s in source}
+
+    source_doc_links = defaultdict(list)
+
+    for link_num, facets in two_facet_links:
+        for span in facets:
+            url, start, length = span
+            source_doc_links[url].append((start, length, link_num, 'link'))
+            if url in source_text:
+                continue
+
+            s = get_text(url)
+            source.append(s)
+            source_text[s['url']] = s['text']
+
+    for s in source_doc_links.values():
+        s.sort()
+
+    spans = list(enumerate(spans))
+
+    doc_spans = []
+    for num, (url, start, length) in spans:
+        highlight = url not in hide_transclusions
+        span_text = source_text[url]  # [start:start + length]
+        new_text = ''
+        pos = start
+        for link_start, link_len, link_num, span_type in source_doc_links[url]:
+            link_end = link_start + link_len
+            if link_start >= start + length:
+                break
+            if link_end < start:
+                continue
+            open_tag = '<span class="xanadoclink link" id="xanalink{}">'.format(link_num)
+            link_span = (open_tag +
+                         escape(span_text[link_start:link_end]) +
+                         '</span>')
+            new_text += escape(span_text[pos:link_start]) + link_span
+            pos = link_end
+        new_text += escape(span_text[pos:start + length])
+        cur = xanadoc_span_html(num, new_text, url, start, length, highlight=highlight)
+        doc_spans.append(cur)
+
+    doc = ''.join(doc_spans)
+
+    for s in source:
+        text = s.pop('text')
+        if s['length'] > max_sourcedoc_size:
+            # print('{} > {}'.format(s['length'], max_sourcedoc_size))
+            continue
+        if s['url'] in hide_transclusions:
+            continue
+        source_spans = [(start, length, num, 'transclusion') for num, (url, start, length) in spans if url == s['url']]
+        source_spans += source_doc_links[s['url']]
+        source_spans.sort()
+
+        new_text = ''
+        pos = 0
+
+        for start, length, num, span_type in source_spans:
+            end = start + length
+            new_text += (escape(text[pos:start]) +
+                         span_html(span_type, num) +
+                         escape(text[start:end]) +
+                         '</span>')
+            pos = end
+        new_text += escape(text[pos:])
+        new_text = new_text.replace('\n', '<br/>\n')
+
+        s['text'] = new_text
+
+    return {
+        'source': source,
+        'doc': doc.replace('\n', '<br/>\n'),
+        'span_count': len(spans),
+        'link_count': len(two_facet_links),
+    }
diff --git a/sourcing/parse.py b/sourcing/parse.py
index 7cda3c3..f2f258a 100644
--- a/sourcing/parse.py
+++ b/sourcing/parse.py
@@ -1,87 +1,22 @@
 import re
-import requests
 import os.path
-import random
 from html import escape
-from collections import defaultdict
 
-re_comment = re.compile(r'#.*')
 re_span_pointer = re.compile(r'span: (.*),start=(\d+),length=(\d+)')
 re_xanalink = re.compile('xanalink: +([^ ]+) *$')
 re_facet = re.compile('^facet\d* *=\s*(.*)\s*$')
-
-re_colon_slash = re.compile('[/:]+')
+re_comment = re.compile(r'#.*')
 
 project_dir = os.path.dirname(os.path.dirname(__file__))
-cache_location = os.path.join(project_dir, 'cache')
-
-max_sourcedoc_size = 600000
 
 xnb_per_char = 150000
 
-censor_urls = {'http://hyperland.com/xuCambDemo/J.Ineffable.txt',
-               'http://royalty.pub/Ineffable/17/32/Trovato'}
-
-def censor_text(text):
-    return ''.join(chr(random.randint(9728, 9983)) if c.isalnum() else c
-                   for c in text)
-
-def get_url(url):
-    filename = os.path.join(cache_location, url_filename(url))
-
-    if os.path.exists(filename):
-        content = open(filename, 'rb').read()
-    else:
-        content = requests.get(url).content
-        open(filename, 'wb').write(content)
-
-    return content.decode(errors='replace')
-
-def get_text(url):
-    # assume UTF-8
-
-    text = get_url(url)
-    if url in censor_urls:
-        text = censor_text(text)
-
-    heading = url.rsplit('/', 1)[-1]
-    return {
-        'url': url,
-        'text': text,
-        'heading': heading,
-        'length': len(text),
-    }
-
 def parse_span(line):
     m = re_span_pointer.match(line)
     if not m:
         return None
     return (m.group(1), int(m.group(2)), int(m.group(3)))
 
-def parse_edl(edl_text):
-    edl = {
-        'spans': [],
-        'links': [],
-    }
-    for line in edl_text.splitlines():
-        line = re_comment.sub('', line).strip()
-        if not line:
-            continue
-        span_pointer = parse_span(line)
-        if span_pointer:
-            edl['spans'].append(span_pointer)
-            continue
-        m = re_xanalink.match(line)
-        if m:
-            link_url = m.group(1)
-            edl['links'].append({
-                'url': link_url,
-                'text': get_url(link_url),
-            })
-            continue
-
-    return edl
-
 def get_span(text, url, start, length):
     return {
         'url': url,
@@ -90,20 +25,9 @@ def get_span(text, url, start, length):
         'text': text[url][start:start + length]
     }
 
-def fulfil_edl(edl):
-    text = {}
-    for url, start, length in parse_edl(edl):
-        if url not in text:
-            text[url] = get_text(url)
-
-        yield get_span(text, url, start, length)
-
 def get_urls(spans):
     return {i[0] for i in spans}
 
-def url_filename(url):
-    return re_colon_slash.sub('_', url)
-
 def find_min_max(spans, source):
     text_min, text_max = {}, {}
     for url, start, length in spans:
@@ -175,99 +99,4 @@ def parse_link(link_text):
             legs.append(line.strip())
     return {'type': link_type, 'facets': facets}
 
-def fulfil_edl_with_sources(edl_text):
-    edl = parse_edl(edl_text)
-    spans = edl['spans']
 
-    hide_transclusions = set()
-
-    two_facet_links = []
-
-    link_num = 0
-    for link in edl['links']:
-        link_detail = parse_link(link['text'])
-        if link_detail['type'] == 'HideTransclusions':
-            hide_transclusions.add(parse_sourcedoc_facet(link_detail['facets'][0]))
-        elif len(link_detail['facets']) == 2:
-            two_facet_links.append((link_num, [parse_span(span[0]) for span in link_detail['facets']]))
-            link_num += 1
-
-    source = [get_text(url) for url in get_urls(spans)]
-
-    source_text = {s['url']: s['text'] for s in source}
-
-    source_doc_links = defaultdict(list)
-
-    for link_num, facets in two_facet_links:
-        for span in facets:
-            url, start, length = span
-            source_doc_links[url].append((start, length, link_num, 'link'))
-            if url in source_text:
-                continue
-
-            s = get_text(url)
-            source.append(s)
-            source_text[s['url']] = s['text']
-
-    for s in source_doc_links.values():
-        s.sort()
-
-    spans = list(enumerate(spans))
-
-    doc_spans = []
-    for num, (url, start, length) in spans:
-        highlight = url not in hide_transclusions
-        span_text = source_text[url]  # [start:start + length]
-        censor = url in censor_urls
-        new_text = ''
-        pos = start
-        for link_start, link_len, link_num, span_type in source_doc_links[url]:
-            link_end = link_start + link_len
-            if link_start >= start + length:
-                break
-            if link_end < start:
-                continue
-            open_tag = '<span class="xanadoclink link" id="xanalink{}">'.format(link_num)
-            link_span = (open_tag +
-                         escape(span_text[link_start:link_end]) +
-                         '</span>')
-            new_text += escape(span_text[pos:link_start]) + link_span
-            pos = link_end
-        new_text += escape(span_text[pos:start + length])
-        cur = xanadoc_span_html(num, new_text, url, start, length, highlight=highlight, censor=censor)
-        doc_spans.append(cur)
-
-    doc = ''.join(doc_spans)
-
-    for s in source:
-        text = s.pop('text')
-        if s['length'] > max_sourcedoc_size:
-            # print('{} > {}'.format(s['length'], max_sourcedoc_size))
-            continue
-        if s['url'] in hide_transclusions:
-            continue
-        source_spans = [(start, length, num, 'transclusion') for num, (url, start, length) in spans if url == s['url']]
-        source_spans += source_doc_links[s['url']]
-        source_spans.sort()
-
-        new_text = ''
-        pos = 0
-
-        for start, length, num, span_type in source_spans:
-            end = start + length
-            new_text += (escape(text[pos:start]) +
-                         span_html(span_type, num) +
-                         escape(text[start:end]) +
-                         '</span>')
-            pos = end
-        new_text += escape(text[pos:])
-        new_text = new_text.replace('\n', '<br/>\n')
-
-        s['text'] = new_text
-
-    return {
-        'source': source,
-        'doc': doc.replace('\n', '<br/>\n'),
-        'span_count': len(spans),
-        'link_count': len(two_facet_links),
-    }
diff --git a/sourcing/static/css/xanadoc.css b/sourcing/static/css/xanadoc.css
new file mode 100644
index 0000000..e18a17f
--- /dev/null
+++ b/sourcing/static/css/xanadoc.css
@@ -0,0 +1,106 @@
+.document {
+    padding: 5px;
+	margin: 10px;
+    background-color: #eee;
+    width: 400px;
+    height: 400px;
+    border: 1px black solid;
+    position: fixed;
+/*     transform: scale(2); */
+}
+
+.sourcedoc {
+    background-color: #ffe;
+}
+
+.xanadoc {
+    background-color: #eef;
+}
+
+.scale {
+    transform: scale(2);
+}
+
+#edlform {
+    padding: 5px;
+	margin: 10px;
+    width: 400px;
+    background-color: #eee;
+    border: 1px black solid;
+    position: fixed;
+    left: 20px;
+    top: 20px;
+}
+
+.heading {
+    background-color: #888;
+    color: white;
+    margin-left: -5px;
+    margin-right: -5px;
+    margin-top: -5px;
+    padding: 5px;
+}
+
+.wrapper {
+    position: absolute;
+    top: 30px;
+    bottom: 0px;
+}
+
+.body {
+    text-align: justify;
+    overflow-y: auto;
+    box-sizing: border-box;
+    height: 100%;
+}
+
+.transclusion {
+    border: solid #FF901A 3px;
+    padding: 1px;
+}
+
+.link {
+    border: solid #33BDFF 3px;
+    padding: 1px;
+}
+
+.hovertransclusion {
+    background-color: #FF901A;
+    padding: 2px;
+}
+
+.hoverlink {
+    background-color: #33BDFF;
+    padding: 2px;
+}
+
+polygon {
+    fill:white;
+    fill-opacity: 0;
+    pointer-events: auto;
+    stroke-width: 3;
+}
+
+polygon.bridge { stroke:#FF901A; }
+polygon.linkbridge { stroke:#33BDFF; }
+polygon.hoverbridge {
+    fill:#FF901A;
+    fill-opacity: 0.75;
+}
+polygon.hoverlinkbridge {
+    fill:#33BDFF;
+    fill-opacity: 0.75;
+}
+
+html, body { margin:0; padding:0; overflow:hidden; }
+svg {
+    position:fixed; top:0; bottom:0; left:0; right:0;
+    z-index: 100000;
+    pointer-events: none;
+}
+
+.paylink {
+    background-color: #33BDFF;
+    color: black;
+    padding: 2px;
+}
diff --git a/sourcing/static/js/interact.js b/sourcing/static/js/interact.js
new file mode 100644
index 0000000..ffbd05d
--- /dev/null
+++ b/sourcing/static/js/interact.js
@@ -0,0 +1,5976 @@
+/**
+ * interact.js v1.2.6
+ *
+ * Copyright (c) 2012-2015 Taye Adeyemi <dev@taye.me>
+ * Open source under the MIT License.
+ * https://raw.github.com/taye/interact.js/master/LICENSE
+ */
+(function (realWindow) {
+    'use strict';
+
+    // return early if there's no window to work with (eg. Node.js)
+    if (!realWindow) { return; }
+
+    var // get wrapped window if using Shadow DOM polyfill
+        window = (function () {
+            // create a TextNode
+            var el = realWindow.document.createTextNode('');
+
+            // check if it's wrapped by a polyfill
+            if (el.ownerDocument !== realWindow.document
+                && typeof realWindow.wrap === 'function'
+                && realWindow.wrap(el) === el) {
+                // return wrapped window
+                return realWindow.wrap(realWindow);
+            }
+
+            // no Shadow DOM polyfil or native implementation
+            return realWindow;
+        }()),
+
+        document           = window.document,
+        DocumentFragment   = window.DocumentFragment   || blank,
+        SVGElement         = window.SVGElement         || blank,
+        SVGSVGElement      = window.SVGSVGElement      || blank,
+        SVGElementInstance = window.SVGElementInstance || blank,
+        HTMLElement        = window.HTMLElement        || window.Element,
+
+        PointerEvent = (window.PointerEvent || window.MSPointerEvent),
+        pEventTypes,
+
+        hypot = Math.hypot || function (x, y) { return Math.sqrt(x * x + y * y); },
+
+        tmpXY = {},     // reduce object creation in getXY()
+
+        documents       = [],   // all documents being listened to
+
+        interactables   = [],   // all set interactables
+        interactions    = [],   // all interactions
+
+        dynamicDrop     = false,
+
+        // {
+        //      type: {
+        //          selectors: ['selector', ...],
+        //          contexts : [document, ...],
+        //          listeners: [[listener, useCapture], ...]
+        //      }
+        //  }
+        delegatedEvents = {},
+
+        defaultOptions = {
+            base: {
+                accept        : null,
+                actionChecker : null,
+                styleCursor   : true,
+                preventDefault: 'auto',
+                origin        : { x: 0, y: 0 },
+                deltaSource   : 'page',
+                allowFrom     : null,
+                ignoreFrom    : null,
+                _context      : document,
+                dropChecker   : null
+            },
+
+            drag: {
+                enabled: false,
+                manualStart: true,
+                max: Infinity,
+                maxPerElement: 1,
+
+                snap: null,
+                restrict: null,
+                inertia: null,
+                autoScroll: null,
+
+                axis: 'xy'
+            },
+
+            drop: {
+                enabled: false,
+                accept: null,
+                overlap: 'pointer'
+            },
+
+            resize: {
+                enabled: false,
+                manualStart: false,
+                max: Infinity,
+                maxPerElement: 1,
+
+                snap: null,
+                restrict: null,
+                inertia: null,
+                autoScroll: null,
+
+                square: false,
+                preserveAspectRatio: false,
+                axis: 'xy',
+
+                // use default margin
+                margin: NaN,
+
+                // object with props left, right, top, bottom which are
+                // true/false values to resize when the pointer is over that edge,
+                // CSS selectors to match the handles for each direction
+                // or the Elements for each handle
+                edges: null,
+
+                // a value of 'none' will limit the resize rect to a minimum of 0x0
+                // 'negate' will alow the rect to have negative width/height
+                // 'reposition' will keep the width/height positive by swapping
+                // the top and bottom edges and/or swapping the left and right edges
+                invert: 'none'
+            },
+
+            gesture: {
+                manualStart: false,
+                enabled: false,
+                max: Infinity,
+                maxPerElement: 1,
+
+                restrict: null
+            },
+
+            perAction: {
+                manualStart: false,
+                max: Infinity,
+                maxPerElement: 1,
+
+                snap: {
+                    enabled     : false,
+                    endOnly     : false,
+                    range       : Infinity,
+                    targets     : null,
+                    offsets     : null,
+
+                    relativePoints: null
+                },
+
+                restrict: {
+                    enabled: false,
+                    endOnly: false
+                },
+
+                autoScroll: {
+                    enabled     : false,
+                    container   : null,     // the item that is scrolled (Window or HTMLElement)
+                    margin      : 60,
+                    speed       : 300       // the scroll speed in pixels per second
+                },
+
+                inertia: {
+                    enabled          : false,
+                    resistance       : 10,    // the lambda in exponential decay
+                    minSpeed         : 100,   // target speed must be above this for inertia to start
+                    endSpeed         : 10,    // the speed at which inertia is slow enough to stop
+                    allowResume      : true,  // allow resuming an action in inertia phase
+                    zeroResumeDelta  : true,  // if an action is resumed after launch, set dx/dy to 0
+                    smoothEndDuration: 300    // animate to snap/restrict endOnly if there's no inertia
+                }
+            },
+
+            _holdDuration: 600
+        },
+
+        // Things related to autoScroll
+        autoScroll = {
+            interaction: null,
+            i: null,    // the handle returned by window.setInterval
+            x: 0, y: 0, // Direction each pulse is to scroll in
+
+            // scroll the window by the values in scroll.x/y
+            scroll: function () {
+                var options = autoScroll.interaction.target.options[autoScroll.interaction.prepared.name].autoScroll,
+                    container = options.container || getWindow(autoScroll.interaction.element),
+                    now = new Date().getTime(),
+                    // change in time in seconds
+                    dtx = (now - autoScroll.prevTimeX) / 1000,
+                    dty = (now - autoScroll.prevTimeY) / 1000,
+                    vx, vy, sx, sy;
+
+                // displacement
+                if (options.velocity) {
+                  vx = options.velocity.x;
+                  vy = options.velocity.y;
+                }
+                else {
+                  vx = vy = options.speed
+                }
+ 
+                sx = vx * dtx;
+                sy = vy * dty;
+
+                if (sx >= 1 || sy >= 1) {
+                    if (isWindow(container)) {
+                        container.scrollBy(autoScroll.x * sx, autoScroll.y * sy);
+                    }
+                    else if (container) {
+                        container.scrollLeft += autoScroll.x * sx;
+                        container.scrollTop  += autoScroll.y * sy;
+                    }
+
+                    if (sx >=1) autoScroll.prevTimeX = now;
+                    if (sy >= 1) autoScroll.prevTimeY = now;
+                }
+
+                if (autoScroll.isScrolling) {
+                    cancelFrame(autoScroll.i);
+                    autoScroll.i = reqFrame(autoScroll.scroll);
+                }
+            },
+
+            isScrolling: false,
+            prevTimeX: 0,
+            prevTimeY: 0,
+
+            start: function (interaction) {
+                autoScroll.isScrolling = true;
+                cancelFrame(autoScroll.i);
+
+                autoScroll.interaction = interaction;
+                autoScroll.prevTimeX = new Date().getTime();
+                autoScroll.prevTimeY = new Date().getTime();
+                autoScroll.i = reqFrame(autoScroll.scroll);
+            },
+
+            stop: function () {
+                autoScroll.isScrolling = false;
+                cancelFrame(autoScroll.i);
+            }
+        },
+
+        // Does the browser support touch input?
+        supportsTouch = (('ontouchstart' in window) || window.DocumentTouch && document instanceof window.DocumentTouch),
+
+        // Does the browser support PointerEvents
+        supportsPointerEvent = !!PointerEvent,
+
+        // Less Precision with touch input
+        margin = supportsTouch || supportsPointerEvent? 20: 10,
+
+        pointerMoveTolerance = 1,
+
+        // for ignoring browser's simulated mouse events
+        prevTouchTime = 0,
+
+        // Allow this many interactions to happen simultaneously
+        maxInteractions = Infinity,
+
+        // Check if is IE9 or older
+        actionCursors = (document.all && !window.atob) ? {
+            drag    : 'move',
+            resizex : 'e-resize',
+            resizey : 's-resize',
+            resizexy: 'se-resize',
+
+            resizetop        : 'n-resize',
+            resizeleft       : 'w-resize',
+            resizebottom     : 's-resize',
+            resizeright      : 'e-resize',
+            resizetopleft    : 'se-resize',
+            resizebottomright: 'se-resize',
+            resizetopright   : 'ne-resize',
+            resizebottomleft : 'ne-resize',
+
+            gesture : ''
+        } : {
+            drag    : 'move',
+            resizex : 'ew-resize',
+            resizey : 'ns-resize',
+            resizexy: 'nwse-resize',
+
+            resizetop        : 'ns-resize',
+            resizeleft       : 'ew-resize',
+            resizebottom     : 'ns-resize',
+            resizeright      : 'ew-resize',
+            resizetopleft    : 'nwse-resize',
+            resizebottomright: 'nwse-resize',
+            resizetopright   : 'nesw-resize',
+            resizebottomleft : 'nesw-resize',
+
+            gesture : ''
+        },
+
+        actionIsEnabled = {
+            drag   : true,
+            resize : true,
+            gesture: true
+        },
+
+        // because Webkit and Opera still use 'mousewheel' event type
+        wheelEvent = 'onmousewheel' in document? 'mousewheel': 'wheel',
+
+        eventTypes = [
+            'dragstart',
+            'dragmove',
+            'draginertiastart',
+            'dragend',
+            'dragenter',
+            'dragleave',
+            'dropactivate',
+            'dropdeactivate',
+            'dropmove',
+            'drop',
+            'resizestart',
+            'resizemove',
+            'resizeinertiastart',
+            'resizeend',
+            'gesturestart',
+            'gesturemove',
+            'gestureinertiastart',
+            'gestureend',
+
+            'down',
+            'move',
+            'up',
+            'cancel',
+            'tap',
+            'doubletap',
+            'hold'
+        ],
+
+        globalEvents = {},
+
+        // Opera Mobile must be handled differently
+        isOperaMobile = navigator.appName == 'Opera' &&
+            supportsTouch &&
+            navigator.userAgent.match('Presto'),
+
+        // scrolling doesn't change the result of getClientRects on iOS 7
+        isIOS7 = (/iP(hone|od|ad)/.test(navigator.platform)
+                         && /OS 7[^\d]/.test(navigator.appVersion)),
+
+        // prefix matchesSelector
+        prefixedMatchesSelector = 'matches' in Element.prototype?
+                'matches': 'webkitMatchesSelector' in Element.prototype?
+                    'webkitMatchesSelector': 'mozMatchesSelector' in Element.prototype?
+                        'mozMatchesSelector': 'oMatchesSelector' in Element.prototype?
+                            'oMatchesSelector': 'msMatchesSelector',
+
+        // will be polyfill function if browser is IE8
+        ie8MatchesSelector,
+
+        // native requestAnimationFrame or polyfill
+        reqFrame = realWindow.requestAnimationFrame,
+        cancelFrame = realWindow.cancelAnimationFrame,
+
+        // Events wrapper
+        events = (function () {
+            var useAttachEvent = ('attachEvent' in window) && !('addEventListener' in window),
+                addEvent       = useAttachEvent?  'attachEvent': 'addEventListener',
+                removeEvent    = useAttachEvent?  'detachEvent': 'removeEventListener',
+                on             = useAttachEvent? 'on': '',
+
+                elements          = [],
+                targets           = [],
+                attachedListeners = [];
+
+            function add (element, type, listener, useCapture) {
+                var elementIndex = indexOf(elements, element),
+                    target = targets[elementIndex];
+
+                if (!target) {
+                    target = {
+                        events: {},
+                        typeCount: 0
+                    };
+
+                    elementIndex = elements.push(element) - 1;
+                    targets.push(target);
+
+                    attachedListeners.push((useAttachEvent ? {
+                            supplied: [],
+                            wrapped : [],
+                            useCount: []
+                        } : null));
+                }
+
+                if (!target.events[type]) {
+                    target.events[type] = [];
+                    target.typeCount++;
+                }
+
+                if (!contains(target.events[type], listener)) {
+                    var ret;
+
+                    if (useAttachEvent) {
+                        var listeners = attachedListeners[elementIndex],
+                            listenerIndex = indexOf(listeners.supplied, listener);
+
+                        var wrapped = listeners.wrapped[listenerIndex] || function (event) {
+                            if (!event.immediatePropagationStopped) {
+                                event.target = event.srcElement;
+                                event.currentTarget = element;
+
+                                event.preventDefault = event.preventDefault || preventDef;
+                                event.stopPropagation = event.stopPropagation || stopProp;
+                                event.stopImmediatePropagation = event.stopImmediatePropagation || stopImmProp;
+
+                                if (/mouse|click/.test(event.type)) {
+                                    event.pageX = event.clientX + getWindow(element).document.documentElement.scrollLeft;
+                                    event.pageY = event.clientY + getWindow(element).document.documentElement.scrollTop;
+                                }
+
+                                listener(event);
+                            }
+                        };
+
+                        ret = element[addEvent](on + type, wrapped, Boolean(useCapture));
+
+                        if (listenerIndex === -1) {
+                            listeners.supplied.push(listener);
+                            listeners.wrapped.push(wrapped);
+                            listeners.useCount.push(1);
+                        }
+                        else {
+                            listeners.useCount[listenerIndex]++;
+                        }
+                    }
+                    else {
+                        ret = element[addEvent](type, listener, useCapture || false);
+                    }
+                    target.events[type].push(listener);
+
+                    return ret;
+                }
+            }
+
+            function remove (element, type, listener, useCapture) {
+                var i,
+                    elementIndex = indexOf(elements, element),
+                    target = targets[elementIndex],
+                    listeners,
+                    listenerIndex,
+                    wrapped = listener;
+
+                if (!target || !target.events) {
+                    return;
+                }
+
+                if (useAttachEvent) {
+                    listeners = attachedListeners[elementIndex];
+                    listenerIndex = indexOf(listeners.supplied, listener);
+                    wrapped = listeners.wrapped[listenerIndex];
+                }
+
+                if (type === 'all') {
+                    for (type in target.events) {
+                        if (target.events.hasOwnProperty(type)) {
+                            remove(element, type, 'all');
+                        }
+                    }
+                    return;
+                }
+
+                if (target.events[type]) {
+                    var len = target.events[type].length;
+
+                    if (listener === 'all') {
+                        for (i = 0; i < len; i++) {
+                            remove(element, type, target.events[type][i], Boolean(useCapture));
+                        }
+                        return;
+                    } else {
+                        for (i = 0; i < len; i++) {
+                            if (target.events[type][i] === listener) {
+                                element[removeEvent](on + type, wrapped, useCapture || false);
+                                target.events[type].splice(i, 1);
+
+                                if (useAttachEvent && listeners) {
+                                    listeners.useCount[listenerIndex]--;
+                                    if (listeners.useCount[listenerIndex] === 0) {
+                                        listeners.supplied.splice(listenerIndex, 1);
+                                        listeners.wrapped.splice(listenerIndex, 1);
+                                        listeners.useCount.splice(listenerIndex, 1);
+                                    }
+                                }
+
+                                break;
+                            }
+                        }
+                    }
+
+                    if (target.events[type] && target.events[type].length === 0) {
+                        target.events[type] = null;
+                        target.typeCount--;
+                    }
+                }
+
+                if (!target.typeCount) {
+                    targets.splice(elementIndex, 1);
+                    elements.splice(elementIndex, 1);
+                    attachedListeners.splice(elementIndex, 1);
+                }
+            }
+
+            function preventDef () {
+                this.returnValue = false;
+            }
+
+            function stopProp () {
+                this.cancelBubble = true;
+            }
+
+            function stopImmProp () {
+                this.cancelBubble = true;
+                this.immediatePropagationStopped = true;
+            }
+
+            return {
+                add: add,
+                remove: remove,
+                useAttachEvent: useAttachEvent,
+
+                _elements: elements,
+                _targets: targets,
+                _attachedListeners: attachedListeners
+            };
+        }());
+
+    function blank () {}
+
+    function isElement (o) {
+        if (!o || (typeof o !== 'object')) { return false; }
+
+        var _window = getWindow(o) || window;
+
+        return (/object|function/.test(typeof _window.Element)
+            ? o instanceof _window.Element //DOM2
+            : o.nodeType === 1 && typeof o.nodeName === "string");
+    }
+    function isWindow (thing) { return thing === window || !!(thing && thing.Window) && (thing instanceof thing.Window); }
+    function isDocFrag (thing) { return !!thing && thing instanceof DocumentFragment; }
+    function isArray (thing) {
+        return isObject(thing)
+                && (typeof thing.length !== undefined)
+                && isFunction(thing.splice);
+    }
+    function isObject   (thing) { return !!thing && (typeof thing === 'object'); }
+    function isFunction (thing) { return typeof thing === 'function'; }
+    function isNumber   (thing) { return typeof thing === 'number'  ; }
+    function isBool     (thing) { return typeof thing === 'boolean' ; }
+    function isString   (thing) { return typeof thing === 'string'  ; }
+
+    function trySelector (value) {
+        if (!isString(value)) { return false; }
+
+        // an exception will be raised if it is invalid
+        document.querySelector(value);
+        return true;
+    }
+
+    function extend (dest, source) {
+        for (var prop in source) {
+            dest[prop] = source[prop];
+        }
+        return dest;
+    }
+
+    var prefixedPropREs = {
+      webkit: /(Movement[XY]|Radius[XY]|RotationAngle|Force)$/
+    };
+
+    function pointerExtend (dest, source) {
+        for (var prop in source) {
+          var deprecated = false;
+
+          // skip deprecated prefixed properties
+          for (var vendor in prefixedPropREs) {
+            if (prop.indexOf(vendor) === 0 && prefixedPropREs[vendor].test(prop)) {
+              deprecated = true;
+              break;
+            }
+          }
+
+          if (!deprecated) {
+            dest[prop] = source[prop];
+          }
+        }
+        return dest;
+    }
+
+    function copyCoords (dest, src) {
+        dest.page = dest.page || {};
+        dest.page.x = src.page.x;
+        dest.page.y = src.page.y;
+
+        dest.client = dest.client || {};
+        dest.client.x = src.client.x;
+        dest.client.y = src.client.y;
+
+        dest.timeStamp = src.timeStamp;
+    }
+
+    function setEventXY (targetObj, pointers, interaction) {
+        var pointer = (pointers.length > 1
+                       ? pointerAverage(pointers)
+                       : pointers[0]);
+
+        getPageXY(pointer, tmpXY, interaction);
+        targetObj.page.x = tmpXY.x;
+        targetObj.page.y = tmpXY.y;
+
+        getClientXY(pointer, tmpXY, interaction);
+        targetObj.client.x = tmpXY.x;
+        targetObj.client.y = tmpXY.y;
+
+        targetObj.timeStamp = new Date().getTime();
+    }
+
+    function setEventDeltas (targetObj, prev, cur) {
+        targetObj.page.x     = cur.page.x      - prev.page.x;
+        targetObj.page.y     = cur.page.y      - prev.page.y;
+        targetObj.client.x   = cur.client.x    - prev.client.x;
+        targetObj.client.y   = cur.client.y    - prev.client.y;
+        targetObj.timeStamp = new Date().getTime() - prev.timeStamp;
+
+        // set pointer velocity
+        var dt = Math.max(targetObj.timeStamp / 1000, 0.001);
+        targetObj.page.speed   = hypot(targetObj.page.x, targetObj.page.y) / dt;
+        targetObj.page.vx      = targetObj.page.x / dt;
+        targetObj.page.vy      = targetObj.page.y / dt;
+
+        targetObj.client.speed = hypot(targetObj.client.x, targetObj.page.y) / dt;
+        targetObj.client.vx    = targetObj.client.x / dt;
+        targetObj.client.vy    = targetObj.client.y / dt;
+    }
+
+    function isNativePointer (pointer) {
+        return (pointer instanceof window.Event
+            || (supportsTouch && window.Touch && pointer instanceof window.Touch));
+    }
+
+    // Get specified X/Y coords for mouse or event.touches[0]
+    function getXY (type, pointer, xy) {
+        xy = xy || {};
+        type = type || 'page';
+
+        xy.x = pointer[type + 'X'];
+        xy.y = pointer[type + 'Y'];
+
+        return xy;
+    }
+
+    function getPageXY (pointer, page) {
+        page = page || {};
+
+        // Opera Mobile handles the viewport and scrolling oddly
+        if (isOperaMobile && isNativePointer(pointer)) {
+            getXY('screen', pointer, page);
+
+            page.x += window.scrollX;
+            page.y += window.scrollY;
+        }
+        else {
+            getXY('page', pointer, page);
+        }
+
+        return page;
+    }
+
+    function getClientXY (pointer, client) {
+        client = client || {};
+
+        if (isOperaMobile && isNativePointer(pointer)) {
+            // Opera Mobile handles the viewport and scrolling oddly
+            getXY('screen', pointer, client);
+        }
+        else {
+          getXY('client', pointer, client);
+        }
+
+        return client;
+    }
+
+    function getScrollXY (win) {
+        win = win || window;
+        return {
+            x: win.scrollX || win.document.documentElement.scrollLeft,
+            y: win.scrollY || win.document.documentElement.scrollTop
+        };
+    }
+
+    function getPointerId (pointer) {
+        return isNumber(pointer.pointerId)? pointer.pointerId : pointer.identifier;
+    }
+
+    function getActualElement (element) {
+        return (element instanceof SVGElementInstance
+            ? element.correspondingUseElement
+            : element);
+    }
+
+    function getWindow (node) {
+        if (isWindow(node)) {
+            return node;
+        }
+
+        var rootNode = (node.ownerDocument || node);
+
+        return rootNode.defaultView || rootNode.parentWindow || window;
+    }
+
+    function getElementClientRect (element) {
+        var clientRect = (element instanceof SVGElement
+                            ? element.getBoundingClientRect()
+                            : element.getClientRects()[0]);
+
+        return clientRect && {
+            left  : clientRect.left,
+            right : clientRect.right,
+            top   : clientRect.top,
+            bottom: clientRect.bottom,
+            width : clientRect.width || clientRect.right - clientRect.left,
+            height: clientRect.height || clientRect.bottom - clientRect.top
+        };
+    }
+
+    function getElementRect (element) {
+        var clientRect = getElementClientRect(element);
+
+        if (!isIOS7 && clientRect) {
+            var scroll = getScrollXY(getWindow(element));
+
+            clientRect.left   += scroll.x;
+            clientRect.right  += scroll.x;
+            clientRect.top    += scroll.y;
+            clientRect.bottom += scroll.y;
+        }
+
+        return clientRect;
+    }
+
+    function getTouchPair (event) {
+        var touches = [];
+
+        // array of touches is supplied
+        if (isArray(event)) {
+            touches[0] = event[0];
+            touches[1] = event[1];
+        }
+        // an event
+        else {
+            if (event.type === 'touchend') {
+                if (event.touches.length === 1) {
+                    touches[0] = event.touches[0];
+                    touches[1] = event.changedTouches[0];
+                }
+                else if (event.touches.length === 0) {
+                    touches[0] = event.changedTouches[0];
+                    touches[1] = event.changedTouches[1];
+                }
+            }
+            else {
+                touches[0] = event.touches[0];
+                touches[1] = event.touches[1];
+            }
+        }
+
+        return touches;
+    }
+
+    function pointerAverage (pointers) {
+        var average = {
+            pageX  : 0,
+            pageY  : 0,
+            clientX: 0,
+            clientY: 0,
+            screenX: 0,
+            screenY: 0
+        };
+        var prop;
+
+        for (var i = 0; i < pointers.length; i++) {
+            for (prop in average) {
+                average[prop] += pointers[i][prop];
+            }
+        }
+        for (prop in average) {
+            average[prop] /= pointers.length;
+        }
+
+        return average;
+    }
+
+    function touchBBox (event) {
+        if (!event.length && !(event.touches && event.touches.length > 1)) {
+            return;
+        }
+
+        var touches = getTouchPair(event),
+            minX = Math.min(touches[0].pageX, touches[1].pageX),
+            minY = Math.min(touches[0].pageY, touches[1].pageY),
+            maxX = Math.max(touches[0].pageX, touches[1].pageX),
+            maxY = Math.max(touches[0].pageY, touches[1].pageY);
+
+        return {
+            x: minX,
+            y: minY,
+            left: minX,
+            top: minY,
+            width: maxX - minX,
+            height: maxY - minY
+        };
+    }
+
+    function touchDistance (event, deltaSource) {
+        deltaSource = deltaSource || defaultOptions.deltaSource;
+
+        var sourceX = deltaSource + 'X',
+            sourceY = deltaSource + 'Y',
+            touches = getTouchPair(event);
+
+
+        var dx = touches[0][sourceX] - touches[1][sourceX],
+            dy = touches[0][sourceY] - touches[1][sourceY];
+
+        return hypot(dx, dy);
+    }
+
+    function touchAngle (event, prevAngle, deltaSource) {
+        deltaSource = deltaSource || defaultOptions.deltaSource;
+
+        var sourceX = deltaSource + 'X',
+            sourceY = deltaSource + 'Y',
+            touches = getTouchPair(event),
+            dx = touches[0][sourceX] - touches[1][sourceX],
+            dy = touches[0][sourceY] - touches[1][sourceY],
+            angle = 180 * Math.atan(dy / dx) / Math.PI;
+
+        if (isNumber(prevAngle)) {
+            var dr = angle - prevAngle,
+                drClamped = dr % 360;
+
+            if (drClamped > 315) {
+                angle -= 360 + (angle / 360)|0 * 360;
+            }
+            else if (drClamped > 135) {
+                angle -= 180 + (angle / 360)|0 * 360;
+            }
+            else if (drClamped < -315) {
+                angle += 360 + (angle / 360)|0 * 360;
+            }
+            else if (drClamped < -135) {
+                angle += 180 + (angle / 360)|0 * 360;
+            }
+        }
+
+        return  angle;
+    }
+
+    function getOriginXY (interactable, element) {
+        var origin = interactable
+                ? interactable.options.origin
+                : defaultOptions.origin;
+
+        if (origin === 'parent') {
+            origin = parentElement(element);
+        }
+        else if (origin === 'self') {
+            origin = interactable.getRect(element);
+        }
+        else if (trySelector(origin)) {
+            origin = closest(element, origin) || { x: 0, y: 0 };
+        }
+
+        if (isFunction(origin)) {
+            origin = origin(interactable && element);
+        }
+
+        if (isElement(origin))  {
+            origin = getElementRect(origin);
+        }
+
+        origin.x = ('x' in origin)? origin.x : origin.left;
+        origin.y = ('y' in origin)? origin.y : origin.top;
+
+        return origin;
+    }
+
+    // http://stackoverflow.com/a/5634528/2280888
+    function _getQBezierValue(t, p1, p2, p3) {
+        var iT = 1 - t;
+        return iT * iT * p1 + 2 * iT * t * p2 + t * t * p3;
+    }
+
+    function getQuadraticCurvePoint(startX, startY, cpX, cpY, endX, endY, position) {
+        return {
+            x:  _getQBezierValue(position, startX, cpX, endX),
+            y:  _getQBezierValue(position, startY, cpY, endY)
+        };
+    }
+
+    // http://gizma.com/easing/
+    function easeOutQuad (t, b, c, d) {
+        t /= d;
+        return -c * t*(t-2) + b;
+    }
+
+    function nodeContains (parent, child) {
+        while (child) {
+            if (child === parent) {
+                return true;
+            }
+
+            child = child.parentNode;
+        }
+
+        return false;
+    }
+
+    function closest (child, selector) {
+        var parent = parentElement(child);
+
+        while (isElement(parent)) {
+            if (matchesSelector(parent, selector)) { return parent; }
+
+            parent = parentElement(parent);
+        }
+
+        return null;
+    }
+
+    function parentElement (node) {
+        var parent = node.parentNode;
+
+        if (isDocFrag(parent)) {
+            // skip past #shado-root fragments
+            while ((parent = parent.host) && isDocFrag(parent)) {}
+
+            return parent;
+        }
+
+        return parent;
+    }
+
+    function inContext (interactable, element) {
+        return interactable._context === element.ownerDocument
+                || nodeContains(interactable._context, element);
+    }
+
+    function testIgnore (interactable, interactableElement, element) {
+        var ignoreFrom = interactable.options.ignoreFrom;
+
+        if (!ignoreFrom || !isElement(element)) { return false; }
+
+        if (isString(ignoreFrom)) {
+            return matchesUpTo(element, ignoreFrom, interactableElement);
+        }
+        else if (isElement(ignoreFrom)) {
+            return nodeContains(ignoreFrom, element);
+        }
+
+        return false;
+    }
+
+    function testAllow (interactable, interactableElement, element) {
+        var allowFrom = interactable.options.allowFrom;
+
+        if (!allowFrom) { return true; }
+
+        if (!isElement(element)) { return false; }
+
+        if (isString(allowFrom)) {
+            return matchesUpTo(element, allowFrom, interactableElement);
+        }
+        else if (isElement(allowFrom)) {
+            return nodeContains(allowFrom, element);
+        }
+
+        return false;
+    }
+
+    function checkAxis (axis, interactable) {
+        if (!interactable) { return false; }
+
+        var thisAxis = interactable.options.drag.axis;
+
+        return (axis === 'xy' || thisAxis === 'xy' || thisAxis === axis);
+    }
+
+    function checkSnap (interactable, action) {
+        var options = interactable.options;
+
+        if (/^resize/.test(action)) {
+            action = 'resize';
+        }
+
+        return options[action].snap && options[action].snap.enabled;
+    }
+
+    function checkRestrict (interactable, action) {
+        var options = interactable.options;
+
+        if (/^resize/.test(action)) {
+            action = 'resize';
+        }
+
+        return  options[action].restrict && options[action].restrict.enabled;
+    }
+
+    function checkAutoScroll (interactable, action) {
+        var options = interactable.options;
+
+        if (/^resize/.test(action)) {
+            action = 'resize';
+        }
+
+        return  options[action].autoScroll && options[action].autoScroll.enabled;
+    }
+
+    function withinInteractionLimit (interactable, element, action) {
+        var options = interactable.options,
+            maxActions = options[action.name].max,
+            maxPerElement = options[action.name].maxPerElement,
+            activeInteractions = 0,
+            targetCount = 0,
+            targetElementCount = 0;
+
+        for (var i = 0, len = interactions.length; i < len; i++) {
+            var interaction = interactions[i],
+                otherAction = interaction.prepared.name,
+                active = interaction.interacting();
+
+            if (!active) { continue; }
+
+            activeInteractions++;
+
+            if (activeInteractions >= maxInteractions) {
+                return false;
+            }
+
+            if (interaction.target !== interactable) { continue; }
+
+            targetCount += (otherAction === action.name)|0;
+
+            if (targetCount >= maxActions) {
+                return false;
+            }
+
+            if (interaction.element === element) {
+                targetElementCount++;
+
+                if (otherAction !== action.name || targetElementCount >= maxPerElement) {
+                    return false;
+                }
+            }
+        }
+
+        return maxInteractions > 0;
+    }
+
+    // Test for the element that's "above" all other qualifiers
+    function indexOfDeepestElement (elements) {
+        var dropzone,
+            deepestZone = elements[0],
+            index = deepestZone? 0: -1,
+            parent,
+            deepestZoneParents = [],
+            dropzoneParents = [],
+            child,
+            i,
+            n;
+
+        for (i = 1; i < elements.length; i++) {
+            dropzone = elements[i];
+
+            // an element might belong to multiple selector dropzones
+            if (!dropzone || dropzone === deepestZone) {
+                continue;
+            }
+
+            if (!deepestZone) {
+                deepestZone = dropzone;
+                index = i;
+                continue;
+            }
+
+            // check if the deepest or current are document.documentElement or document.rootElement
+            // - if the current dropzone is, do nothing and continue
+            if (dropzone.parentNode === dropzone.ownerDocument) {
+                continue;
+            }
+            // - if deepest is, update with the current dropzone and continue to next
+            else if (deepestZone.parentNode === dropzone.ownerDocument) {
+                deepestZone = dropzone;
+                index = i;
+                continue;
+            }
+
+            if (!deepestZoneParents.length) {
+                parent = deepestZone;
+                while (parent.parentNode && parent.parentNode !== parent.ownerDocument) {
+                    deepestZoneParents.unshift(parent);
+                    parent = parent.parentNode;
+                }
+            }
+
+            // if this element is an svg element and the current deepest is
+            // an HTMLElement
+            if (deepestZone instanceof HTMLElement
+                && dropzone instanceof SVGElement
+                && !(dropzone instanceof SVGSVGElement)) {
+
+                if (dropzone === deepestZone.parentNode) {
+                    continue;
+                }
+
+                parent = dropzone.ownerSVGElement;
+            }
+            else {
+                parent = dropzone;
+            }
+
+            dropzoneParents = [];
+
+            while (parent.parentNode !== parent.ownerDocument) {
+                dropzoneParents.unshift(parent);
+                parent = parent.parentNode;
+            }
+
+            n = 0;
+
+            // get (position of last common ancestor) + 1
+            while (dropzoneParents[n] && dropzoneParents[n] === deepestZoneParents[n]) {
+                n++;
+            }
+
+            var parents = [
+                dropzoneParents[n - 1],
+                dropzoneParents[n],
+                deepestZoneParents[n]
+            ];
+
+            child = parents[0].lastChild;
+
+            while (child) {
+                if (child === parents[1]) {
+                    deepestZone = dropzone;
+                    index = i;
+                    deepestZoneParents = [];
+
+                    break;
+                }
+                else if (child === parents[2]) {
+                    break;
+                }
+
+                child = child.previousSibling;
+            }
+        }
+
+        return index;
+    }
+
+    function Interaction () {
+        this.target          = null; // current interactable being interacted with
+        this.element         = null; // the target element of the interactable
+        this.dropTarget      = null; // the dropzone a drag target might be dropped into
+        this.dropElement     = null; // the element at the time of checking
+        this.prevDropTarget  = null; // the dropzone that was recently dragged away from
+        this.prevDropElement = null; // the element at the time of checking
+
+        this.prepared        = {     // action that's ready to be fired on next move event
+            name : null,
+            axis : null,
+            edges: null
+        };
+
+        this.matches         = [];   // all selectors that are matched by target element
+        this.matchElements   = [];   // corresponding elements
+
+        this.inertiaStatus = {
+            active       : false,
+            smoothEnd    : false,
+            ending       : false,
+
+            startEvent: null,
+            upCoords: {},
+
+            xe: 0, ye: 0,
+            sx: 0, sy: 0,
+
+            t0: 0,
+            vx0: 0, vys: 0,
+            duration: 0,
+
+            resumeDx: 0,
+            resumeDy: 0,
+
+            lambda_v0: 0,
+            one_ve_v0: 0,
+            i  : null
+        };
+
+        if (isFunction(Function.prototype.bind)) {
+            this.boundInertiaFrame = this.inertiaFrame.bind(this);
+            this.boundSmoothEndFrame = this.smoothEndFrame.bind(this);
+        }
+        else {
+            var that = this;
+
+            this.boundInertiaFrame = function () { return that.inertiaFrame(); };
+            this.boundSmoothEndFrame = function () { return that.smoothEndFrame(); };
+        }
+
+        this.activeDrops = {
+            dropzones: [],      // the dropzones that are mentioned below
+            elements : [],      // elements of dropzones that accept the target draggable
+            rects    : []       // the rects of the elements mentioned above
+        };
+
+        // keep track of added pointers
+        this.pointers    = [];
+        this.pointerIds  = [];
+        this.downTargets = [];
+        this.downTimes   = [];
+        this.holdTimers  = [];
+
+        // Previous native pointer move event coordinates
+        this.prevCoords = {
+            page     : { x: 0, y: 0 },
+            client   : { x: 0, y: 0 },
+            timeStamp: 0
+        };
+        // current native pointer move event coordinates
+        this.curCoords = {
+            page     : { x: 0, y: 0 },
+            client   : { x: 0, y: 0 },
+            timeStamp: 0
+        };
+
+        // Starting InteractEvent pointer coordinates
+        this.startCoords = {
+            page     : { x: 0, y: 0 },
+            client   : { x: 0, y: 0 },
+            timeStamp: 0
+        };
+
+        // Change in coordinates and time of the pointer
+        this.pointerDelta = {
+            page     : { x: 0, y: 0, vx: 0, vy: 0, speed: 0 },
+            client   : { x: 0, y: 0, vx: 0, vy: 0, speed: 0 },
+            timeStamp: 0
+        };
+
+        this.downEvent   = null;    // pointerdown/mousedown/touchstart event
+        this.downPointer = {};
+
+        this._eventTarget    = null;
+        this._curEventTarget = null;
+
+        this.prevEvent = null;      // previous action event
+        this.tapTime   = 0;         // time of the most recent tap event
+        this.prevTap   = null;
+
+        this.startOffset    = { left: 0, right: 0, top: 0, bottom: 0 };
+        this.restrictOffset = { left: 0, right: 0, top: 0, bottom: 0 };
+        this.snapOffsets    = [];
+
+        this.gesture = {
+            start: { x: 0, y: 0 },
+
+            startDistance: 0,   // distance between two touches of touchStart
+            prevDistance : 0,
+            distance     : 0,
+
+            scale: 1,           // gesture.distance / gesture.startDistance
+
+            startAngle: 0,      // angle of line joining two touches
+            prevAngle : 0       // angle of the previous gesture event
+        };
+
+        this.snapStatus = {
+            x       : 0, y       : 0,
+            dx      : 0, dy      : 0,
+            realX   : 0, realY   : 0,
+            snappedX: 0, snappedY: 0,
+            targets : [],
+            locked  : false,
+            changed : false
+        };
+
+        this.restrictStatus = {
+            dx         : 0, dy         : 0,
+            restrictedX: 0, restrictedY: 0,
+            snap       : null,
+            restricted : false,
+            changed    : false
+        };
+
+        this.restrictStatus.snap = this.snapStatus;
+
+        this.pointerIsDown   = false;
+        this.pointerWasMoved = false;
+        this.gesturing       = false;
+        this.dragging        = false;
+        this.resizing        = false;
+        this.resizeAxes      = 'xy';
+
+        this.mouse = false;
+
+        interactions.push(this);
+    }
+
+    Interaction.prototype = {
+        getPageXY  : function (pointer, xy) { return   getPageXY(pointer, xy, this); },
+        getClientXY: function (pointer, xy) { return getClientXY(pointer, xy, this); },
+        setEventXY : function (target, ptr) { return  setEventXY(target, ptr, this); },
+
+        pointerOver: function (pointer, event, eventTarget) {
+            if (this.prepared.name || !this.mouse) { return; }
+
+            var curMatches = [],
+                curMatchElements = [],
+                prevTargetElement = this.element;
+
+            this.addPointer(pointer);
+
+            if (this.target
+                && (testIgnore(this.target, this.element, eventTarget)
+                    || !testAllow(this.target, this.element, eventTarget))) {
+                // if the eventTarget should be ignored or shouldn't be allowed
+                // clear the previous target
+                this.target = null;
+                this.element = null;
+                this.matches = [];
+                this.matchElements = [];
+            }
+
+            var elementInteractable = interactables.get(eventTarget),
+                elementAction = (elementInteractable
+                                 && !testIgnore(elementInteractable, eventTarget, eventTarget)
+                                 && testAllow(elementInteractable, eventTarget, eventTarget)
+                                 && validateAction(
+                                     elementInteractable.getAction(pointer, event, this, eventTarget),
+                                     elementInteractable));
+
+            if (elementAction && !withinInteractionLimit(elementInteractable, eventTarget, elementAction)) {
+                 elementAction = null;
+            }
+
+            function pushCurMatches (interactable, selector) {
+                if (interactable
+                    && inContext(interactable, eventTarget)
+                    && !testIgnore(interactable, eventTarget, eventTarget)
+                    && testAllow(interactable, eventTarget, eventTarget)
+                    && matchesSelector(eventTarget, selector)) {
+
+                    curMatches.push(interactable);
+                    curMatchElements.push(eventTarget);
+                }
+            }
+
+            if (elementAction) {
+                this.target = elementInteractable;
+                this.element = eventTarget;
+                this.matches = [];
+                this.matchElements = [];
+            }
+            else {
+                interactables.forEachSelector(pushCurMatches);
+
+                if (this.validateSelector(pointer, event, curMatches, curMatchElements)) {
+                    this.matches = curMatches;
+                    this.matchElements = curMatchElements;
+
+                    this.pointerHover(pointer, event, this.matches, this.matchElements);
+                    events.add(eventTarget,
+                                        PointerEvent? pEventTypes.move : 'mousemove',
+                                        listeners.pointerHover);
+                }
+                else if (this.target) {
+                    if (nodeContains(prevTargetElement, eventTarget)) {
+                        this.pointerHover(pointer, event, this.matches, this.matchElements);
+                        events.add(this.element,
+                                            PointerEvent? pEventTypes.move : 'mousemove',
+                                            listeners.pointerHover);
+                    }
+                    else {
+                        this.target = null;
+                        this.element = null;
+                        this.matches = [];
+                        this.matchElements = [];
+                    }
+                }
+            }
+        },
+
+        // Check what action would be performed on pointerMove target if a mouse
+        // button were pressed and change the cursor accordingly
+        pointerHover: function (pointer, event, eventTarget, curEventTarget, matches, matchElements) {
+            var target = this.target;
+
+            if (!this.prepared.name && this.mouse) {
+
+                var action;
+
+                // update pointer coords for defaultActionChecker to use
+                this.setEventXY(this.curCoords, [pointer]);
+
+                if (matches) {
+                    action = this.validateSelector(pointer, event, matches, matchElements);
+                }
+                else if (target) {
+                    action = validateAction(target.getAction(this.pointers[0], event, this, this.element), this.target);
+                }
+
+                if (target && target.options.styleCursor) {
+                    if (action) {
+                        target._doc.documentElement.style.cursor = getActionCursor(action);
+                    }
+                    else {
+                        target._doc.documentElement.style.cursor = '';
+                    }
+                }
+            }
+            else if (this.prepared.name) {
+                this.checkAndPreventDefault(event, target, this.element);
+            }
+        },
+
+        pointerOut: function (pointer, event, eventTarget) {
+            if (this.prepared.name) { return; }
+
+            // Remove temporary event listeners for selector Interactables
+            if (!interactables.get(eventTarget)) {
+                events.remove(eventTarget,
+                                       PointerEvent? pEventTypes.move : 'mousemove',
+                                       listeners.pointerHover);
+            }
+
+            if (this.target && this.target.options.styleCursor && !this.interacting()) {
+                this.target._doc.documentElement.style.cursor = '';
+            }
+        },
+
+        selectorDown: function (pointer, event, eventTarget, curEventTarget) {
+            var that = this,
+                // copy event to be used in timeout for IE8
+                eventCopy = events.useAttachEvent? extend({}, event) : event,
+                element = eventTarget,
+                pointerIndex = this.addPointer(pointer),
+                action;
+
+            this.holdTimers[pointerIndex] = setTimeout(function () {
+                that.pointerHold(events.useAttachEvent? eventCopy : pointer, eventCopy, eventTarget, curEventTarget);
+            }, defaultOptions._holdDuration);
+
+            this.pointerIsDown = true;
+
+            // Check if the down event hits the current inertia target
+            if (this.inertiaStatus.active && this.target.selector) {
+                // climb up the DOM tree from the event target
+                while (isElement(element)) {
+
+                    // if this element is the current inertia target element
+                    if (element === this.element
+                        // and the prospective action is the same as the ongoing one
+                        && validateAction(this.target.getAction(pointer, event, this, this.element), this.target).name === this.prepared.name) {
+
+                        // stop inertia so that the next move will be a normal one
+                        cancelFrame(this.inertiaStatus.i);
+                        this.inertiaStatus.active = false;
+
+                        this.collectEventTargets(pointer, event, eventTarget, 'down');
+                        return;
+                    }
+                    element = parentElement(element);
+                }
+            }
+
+            // do nothing if interacting
+            if (this.interacting()) {
+                this.collectEventTargets(pointer, event, eventTarget, 'down');
+                return;
+            }
+
+            function pushMatches (interactable, selector, context) {
+                var elements = ie8MatchesSelector
+                    ? context.querySelectorAll(selector)
+                    : undefined;
+
+                if (inContext(interactable, element)
+                    && !testIgnore(interactable, element, eventTarget)
+                    && testAllow(interactable, element, eventTarget)
+                    && matchesSelector(element, selector, elements)) {
+
+                    that.matches.push(interactable);
+                    that.matchElements.push(element);
+                }
+            }
+
+            // update pointer coords for defaultActionChecker to use
+            this.setEventXY(this.curCoords, [pointer]);
+            this.downEvent = event;
+
+            while (isElement(element) && !action) {
+                this.matches = [];
+                this.matchElements = [];
+
+                interactables.forEachSelector(pushMatches);
+
+                action = this.validateSelector(pointer, event, this.matches, this.matchElements);
+                element = parentElement(element);
+            }
+
+            if (action) {
+                this.prepared.name  = action.name;
+                this.prepared.axis  = action.axis;
+                this.prepared.edges = action.edges;
+
+                this.collectEventTargets(pointer, event, eventTarget, 'down');
+
+                return this.pointerDown(pointer, event, eventTarget, curEventTarget, action);
+            }
+            else {
+                // do these now since pointerDown isn't being called from here
+                this.downTimes[pointerIndex] = new Date().getTime();
+                this.downTargets[pointerIndex] = eventTarget;
+                pointerExtend(this.downPointer, pointer);
+
+                copyCoords(this.prevCoords, this.curCoords);
+                this.pointerWasMoved = false;
+            }
+
+            this.collectEventTargets(pointer, event, eventTarget, 'down');
+        },
+
+        // Determine action to be performed on next pointerMove and add appropriate
+        // style and event Listeners
+        pointerDown: function (pointer, event, eventTarget, curEventTarget, forceAction) {
+            if (!forceAction && !this.inertiaStatus.active && this.pointerWasMoved && this.prepared.name) {
+                this.checkAndPreventDefault(event, this.target, this.element);
+
+                return;
+            }
+
+            this.pointerIsDown = true;
+            this.downEvent = event;
+
+            var pointerIndex = this.addPointer(pointer),
+                action;
+
+            // If it is the second touch of a multi-touch gesture, keep the
+            // target the same and get a new action if a target was set by the
+            // first touch
+            if (this.pointerIds.length > 1 && this.target._element === this.element) {
+                var newAction = validateAction(forceAction || this.target.getAction(pointer, event, this, this.element), this.target);
+
+                if (withinInteractionLimit(this.target, this.element, newAction)) {
+                    action = newAction;
+                }
+
+                this.prepared.name = null;
+            }
+            // Otherwise, set the target if there is no action prepared
+            else if (!this.prepared.name) {
+                var interactable = interactables.get(curEventTarget);
+
+                if (interactable
+                    && !testIgnore(interactable, curEventTarget, eventTarget)
+                    && testAllow(interactable, curEventTarget, eventTarget)
+                    && (action = validateAction(forceAction || interactable.getAction(pointer, event, this, curEventTarget), interactable, eventTarget))
+                    && withinInteractionLimit(interactable, curEventTarget, action)) {
+                    this.target = interactable;
+                    this.element = curEventTarget;
+                }
+            }
+
+            var target = this.target,
+                options = target && target.options;
+
+            if (target && (forceAction || !this.prepared.name)) {
+                action = action || validateAction(forceAction || target.getAction(pointer, event, this, curEventTarget), target, this.element);
+
+                this.setEventXY(this.startCoords, this.pointers);
+
+                if (!action) { return; }
+
+                if (options.styleCursor) {
+                    target._doc.documentElement.style.cursor = getActionCursor(action);
+                }
+
+                this.resizeAxes = action.name === 'resize'? action.axis : null;
+
+                if (action === 'gesture' && this.pointerIds.length < 2) {
+                    action = null;
+                }
+
+                this.prepared.name  = action.name;
+                this.prepared.axis  = action.axis;
+                this.prepared.edges = action.edges;
+
+                this.snapStatus.snappedX = this.snapStatus.snappedY =
+                    this.restrictStatus.restrictedX = this.restrictStatus.restrictedY = NaN;
+
+                this.downTimes[pointerIndex] = new Date().getTime();
+                this.downTargets[pointerIndex] = eventTarget;
+                pointerExtend(this.downPointer, pointer);
+
+                copyCoords(this.prevCoords, this.startCoords);
+                this.pointerWasMoved = false;
+
+                this.checkAndPreventDefault(event, target, this.element);
+            }
+            // if inertia is active try to resume action
+            else if (this.inertiaStatus.active
+                && curEventTarget === this.element
+                && validateAction(target.getAction(pointer, event, this, this.element), target).name === this.prepared.name) {
+
+                cancelFrame(this.inertiaStatus.i);
+                this.inertiaStatus.active = false;
+
+                this.checkAndPreventDefault(event, target, this.element);
+            }
+        },
+
+        setModifications: function (coords, preEnd) {
+            var target         = this.target,
+                shouldMove     = true,
+                shouldSnap     = checkSnap(target, this.prepared.name)     && (!target.options[this.prepared.name].snap.endOnly     || preEnd),
+                shouldRestrict = checkRestrict(target, this.prepared.name) && (!target.options[this.prepared.name].restrict.endOnly || preEnd);
+
+            if (shouldSnap    ) { this.setSnapping   (coords); } else { this.snapStatus    .locked     = false; }
+            if (shouldRestrict) { this.setRestriction(coords); } else { this.restrictStatus.restricted = false; }
+
+            if (shouldSnap && this.snapStatus.locked && !this.snapStatus.changed) {
+                shouldMove = shouldRestrict && this.restrictStatus.restricted && this.restrictStatus.changed;
+            }
+            else if (shouldRestrict && this.restrictStatus.restricted && !this.restrictStatus.changed) {
+                shouldMove = false;
+            }
+
+            return shouldMove;
+        },
+
+        setStartOffsets: function (action, interactable, element) {
+            var rect = interactable.getRect(element),
+                origin = getOriginXY(interactable, element),
+                snap = interactable.options[this.prepared.name].snap,
+                restrict = interactable.options[this.prepared.name].restrict,
+                width, height;
+
+            if (rect) {
+                this.startOffset.left = this.startCoords.page.x - rect.left;
+                this.startOffset.top  = this.startCoords.page.y - rect.top;
+
+                this.startOffset.right  = rect.right  - this.startCoords.page.x;
+                this.startOffset.bottom = rect.bottom - this.startCoords.page.y;
+
+                if ('width' in rect) { width = rect.width; }
+                else { width = rect.right - rect.left; }
+                if ('height' in rect) { height = rect.height; }
+                else { height = rect.bottom - rect.top; }
+            }
+            else {
+                this.startOffset.left = this.startOffset.top = this.startOffset.right = this.startOffset.bottom = 0;
+            }
+
+            this.snapOffsets.splice(0);
+
+            var snapOffset = snap && snap.offset === 'startCoords'
+                                ? {
+                                    x: this.startCoords.page.x - origin.x,
+                                    y: this.startCoords.page.y - origin.y
+                                }
+                                : snap && snap.offset || { x: 0, y: 0 };
+
+            if (rect && snap && snap.relativePoints && snap.relativePoints.length) {
+                for (var i = 0; i < snap.relativePoints.length; i++) {
+                    this.snapOffsets.push({
+                        x: this.startOffset.left - (width  * snap.relativePoints[i].x) + snapOffset.x,
+                        y: this.startOffset.top  - (height * snap.relativePoints[i].y) + snapOffset.y
+                    });
+                }
+            }
+            else {
+                this.snapOffsets.push(snapOffset);
+            }
+
+            if (rect && restrict.elementRect) {
+                this.restrictOffset.left = this.startOffset.left - (width  * restrict.elementRect.left);
+                this.restrictOffset.top  = this.startOffset.top  - (height * restrict.elementRect.top);
+
+                this.restrictOffset.right  = this.startOffset.right  - (width  * (1 - restrict.elementRect.right));
+                this.restrictOffset.bottom = this.startOffset.bottom - (height * (1 - restrict.elementRect.bottom));
+            }
+            else {
+                this.restrictOffset.left = this.restrictOffset.top = this.restrictOffset.right = this.restrictOffset.bottom = 0;
+            }
+        },
+
+        /*\
+         * Interaction.start
+         [ method ]
+         *
+         * Start an action with the given Interactable and Element as tartgets. The
+         * action must be enabled for the target Interactable and an appropriate number
+         * of pointers must be held down – 1 for drag/resize, 2 for gesture.
+         *
+         * Use it with `interactable.<action>able({ manualStart: false })` to always
+         * [start actions manually](https://github.com/taye/interact.js/issues/114)
+         *
+         - action       (object)  The action to be performed - drag, resize, etc.
+         - interactable (Interactable) The Interactable to target
+         - element      (Element) The DOM Element to target
+         = (object) interact
+         **
+         | interact(target)
+         |   .draggable({
+         |     // disable the default drag start by down->move
+         |     manualStart: true
+         |   })
+         |   // start dragging after the user holds the pointer down
+         |   .on('hold', function (event) {
+         |     var interaction = event.interaction;
+         |
+         |     if (!interaction.interacting()) {
+         |       interaction.start({ name: 'drag' },
+         |                         event.interactable,
+         |                         event.currentTarget);
+         |     }
+         | });
+        \*/
+        start: function (action, interactable, element) {
+            if (this.interacting()
+                || !this.pointerIsDown
+                || this.pointerIds.length < (action.name === 'gesture'? 2 : 1)) {
+                return;
+            }
+
+            // if this interaction had been removed after stopping
+            // add it back
+            if (indexOf(interactions, this) === -1) {
+                interactions.push(this);
+            }
+
+            // set the startCoords if there was no prepared action
+            if (!this.prepared.name) {
+                this.setEventXY(this.startCoords);
+            }
+
+            this.prepared.name  = action.name;
+            this.prepared.axis  = action.axis;
+            this.prepared.edges = action.edges;
+            this.target         = interactable;
+            this.element        = element;
+
+            this.setStartOffsets(action.name, interactable, element);
+            this.setModifications(this.startCoords.page);
+
+            this.prevEvent = this[this.prepared.name + 'Start'](this.downEvent);
+        },
+
+        pointerMove: function (pointer, event, eventTarget, curEventTarget, preEnd) {
+            if (this.inertiaStatus.active) {
+                var pageUp   = this.inertiaStatus.upCoords.page;
+                var clientUp = this.inertiaStatus.upCoords.client;
+
+                var inertiaPosition = {
+                    pageX  : pageUp.x   + this.inertiaStatus.sx,
+                    pageY  : pageUp.y   + this.inertiaStatus.sy,
+                    clientX: clientUp.x + this.inertiaStatus.sx,
+                    clientY: clientUp.y + this.inertiaStatus.sy
+                };
+
+                this.setEventXY(this.curCoords, [inertiaPosition]);
+            }
+            else {
+                this.recordPointer(pointer);
+                this.setEventXY(this.curCoords, this.pointers);
+            }
+
+            var duplicateMove = (this.curCoords.page.x === this.prevCoords.page.x
+                                 && this.curCoords.page.y === this.prevCoords.page.y
+                                 && this.curCoords.client.x === this.prevCoords.client.x
+                                 && this.curCoords.client.y === this.prevCoords.client.y);
+
+            var dx, dy,
+                pointerIndex = this.mouse? 0 : indexOf(this.pointerIds, getPointerId(pointer));
+
+            // register movement greater than pointerMoveTolerance
+            if (this.pointerIsDown && !this.pointerWasMoved) {
+                dx = this.curCoords.client.x - this.startCoords.client.x;
+                dy = this.curCoords.client.y - this.startCoords.client.y;
+
+                this.pointerWasMoved = hypot(dx, dy) > pointerMoveTolerance;
+            }
+
+            if (!duplicateMove && (!this.pointerIsDown || this.pointerWasMoved)) {
+                if (this.pointerIsDown) {
+                    clearTimeout(this.holdTimers[pointerIndex]);
+                }
+
+                this.collectEventTargets(pointer, event, eventTarget, 'move');
+            }
+
+            if (!this.pointerIsDown) { return; }
+
+            if (duplicateMove && this.pointerWasMoved && !preEnd) {
+                this.checkAndPreventDefault(event, this.target, this.element);
+                return;
+            }
+
+            // set pointer coordinate, time changes and speeds
+            setEventDeltas(this.pointerDelta, this.prevCoords, this.curCoords);
+
+            if (!this.prepared.name) { return; }
+
+            if (this.pointerWasMoved
+                // ignore movement while inertia is active
+                && (!this.inertiaStatus.active || (pointer instanceof InteractEvent && /inertiastart/.test(pointer.type)))) {
+
+                // if just starting an action, calculate the pointer speed now
+                if (!this.interacting()) {
+                    setEventDeltas(this.pointerDelta, this.prevCoords, this.curCoords);
+
+                    // check if a drag is in the correct axis
+                    if (this.prepared.name === 'drag') {
+                        var absX = Math.abs(dx),
+                            absY = Math.abs(dy),
+                            targetAxis = this.target.options.drag.axis,
+                            axis = (absX > absY ? 'x' : absX < absY ? 'y' : 'xy');
+
+                        // if the movement isn't in the axis of the interactable
+                        if (axis !== 'xy' && targetAxis !== 'xy' && targetAxis !== axis) {
+                            // cancel the prepared action
+                            this.prepared.name = null;
+
+                            // then try to get a drag from another ineractable
+
+                            var element = eventTarget;
+
+                            // check element interactables
+                            while (isElement(element)) {
+                                var elementInteractable = interactables.get(element);
+
+                                if (elementInteractable
+                                    && elementInteractable !== this.target
+                                    && !elementInteractable.options.drag.manualStart
+                                    && elementInteractable.getAction(this.downPointer, this.downEvent, this, element).name === 'drag'
+                                    && checkAxis(axis, elementInteractable)) {
+
+                                    this.prepared.name = 'drag';
+                                    this.target = elementInteractable;
+                                    this.element = element;
+                                    break;
+                                }
+
+                                element = parentElement(element);
+                            }
+
+                            // if there's no drag from element interactables,
+                            // check the selector interactables
+                            if (!this.prepared.name) {
+                                var thisInteraction = this;
+
+                                var getDraggable = function (interactable, selector, context) {
+                                    var elements = ie8MatchesSelector
+                                        ? context.querySelectorAll(selector)
+                                        : undefined;
+
+                                    if (interactable === thisInteraction.target) { return; }
+
+                                    if (inContext(interactable, eventTarget)
+                                        && !interactable.options.drag.manualStart
+                                        && !testIgnore(interactable, element, eventTarget)
+                                        && testAllow(interactable, element, eventTarget)
+                                        && matchesSelector(element, selector, elements)
+                                        && interactable.getAction(thisInteraction.downPointer, thisInteraction.downEvent, thisInteraction, element).name === 'drag'
+                                        && checkAxis(axis, interactable)
+                                        && withinInteractionLimit(interactable, element, 'drag')) {
+
+                                        return interactable;
+                                    }
+                                };
+
+                                element = eventTarget;
+
+                                while (isElement(element)) {
+                                    var selectorInteractable = interactables.forEachSelector(getDraggable);
+
+                                    if (selectorInteractable) {
+                                        this.prepared.name = 'drag';
+                                        this.target = selectorInteractable;
+                                        this.element = element;
+                                        break;
+                                    }
+
+                                    element = parentElement(element);
+                                }
+                            }
+                        }
+                    }
+                }
+
+                var starting = !!this.prepared.name && !this.interacting();
+
+                if (starting
+                    && (this.target.options[this.prepared.name].manualStart
+                        || !withinInteractionLimit(this.target, this.element, this.prepared))) {
+                    this.stop(event);
+                    return;
+                }
+
+                if (this.prepared.name && this.target) {
+                    if (starting) {
+                        this.start(this.prepared, this.target, this.element);
+                    }
+
+                    var shouldMove = this.setModifications(this.curCoords.page, preEnd);
+
+                    // move if snapping or restriction doesn't prevent it
+                    if (shouldMove || starting) {
+                        this.prevEvent = this[this.prepared.name + 'Move'](event);
+                    }
+
+                    this.checkAndPreventDefault(event, this.target, this.element);
+                }
+            }
+
+            copyCoords(this.prevCoords, this.curCoords);
+
+            if (this.dragging || this.resizing) {
+                this.autoScrollMove(pointer);
+            }
+        },
+
+        dragStart: function (event) {
+            var dragEvent = new InteractEvent(this, event, 'drag', 'start', this.element);
+
+            this.dragging = true;
+            this.target.fire(dragEvent);
+
+            // reset active dropzones
+            this.activeDrops.dropzones = [];
+            this.activeDrops.elements  = [];
+            this.activeDrops.rects     = [];
+
+            if (!this.dynamicDrop) {
+                this.setActiveDrops(this.element);
+            }
+
+            var dropEvents = this.getDropEvents(event, dragEvent);
+
+            if (dropEvents.activate) {
+                this.fireActiveDrops(dropEvents.activate);
+            }
+
+            return dragEvent;
+        },
+
+        dragMove: function (event) {
+            var target = this.target,
+                dragEvent  = new InteractEvent(this, event, 'drag', 'move', this.element),
+                draggableElement = this.element,
+                drop = this.getDrop(dragEvent, event, draggableElement);
+
+            this.dropTarget = drop.dropzone;
+            this.dropElement = drop.element;
+
+            var dropEvents = this.getDropEvents(event, dragEvent);
+
+            target.fire(dragEvent);
+
+            if (dropEvents.leave) { this.prevDropTarget.fire(dropEvents.leave); }
+            if (dropEvents.enter) {     this.dropTarget.fire(dropEvents.enter); }
+            if (dropEvents.move ) {     this.dropTarget.fire(dropEvents.move ); }
+
+            this.prevDropTarget  = this.dropTarget;
+            this.prevDropElement = this.dropElement;
+
+            return dragEvent;
+        },
+
+        resizeStart: function (event) {
+            var resizeEvent = new InteractEvent(this, event, 'resize', 'start', this.element);
+
+            if (this.prepared.edges) {
+                var startRect = this.target.getRect(this.element);
+
+                /*
+                 * When using the `resizable.square` or `resizable.preserveAspectRatio` options, resizing from one edge
+                 * will affect another. E.g. with `resizable.square`, resizing to make the right edge larger will make
+                 * the bottom edge larger by the same amount. We call these 'linked' edges. Any linked edges will depend
+                 * on the active edges and the edge being interacted with.
+                 */
+                if (this.target.options.resize.square || this.target.options.resize.preserveAspectRatio) {
+                    var linkedEdges = extend({}, this.prepared.edges);
+
+                    linkedEdges.top    = linkedEdges.top    || (linkedEdges.left   && !linkedEdges.bottom);
+                    linkedEdges.left   = linkedEdges.left   || (linkedEdges.top    && !linkedEdges.right );
+                    linkedEdges.bottom = linkedEdges.bottom || (linkedEdges.right  && !linkedEdges.top   );
+                    linkedEdges.right  = linkedEdges.right  || (linkedEdges.bottom && !linkedEdges.left  );
+
+                    this.prepared._linkedEdges = linkedEdges;
+                }
+                else {
+                    this.prepared._linkedEdges = null;
+                }
+
+                // if using `resizable.preserveAspectRatio` option, record aspect ratio at the start of the resize
+                if (this.target.options.resize.preserveAspectRatio) {
+                    this.resizeStartAspectRatio = startRect.width / startRect.height;
+                }
+
+                this.resizeRects = {
+                    start     : startRect,
+                    current   : extend({}, startRect),
+                    restricted: extend({}, startRect),
+                    previous  : extend({}, startRect),
+                    delta     : {
+                        left: 0, right : 0, width : 0,
+                        top : 0, bottom: 0, height: 0
+                    }
+                };
+
+                resizeEvent.rect = this.resizeRects.restricted;
+                resizeEvent.deltaRect = this.resizeRects.delta;
+            }
+
+            this.target.fire(resizeEvent);
+
+            this.resizing = true;
+
+            return resizeEvent;
+        },
+
+        resizeMove: function (event) {
+            var resizeEvent = new InteractEvent(this, event, 'resize', 'move', this.element);
+
+            var edges = this.prepared.edges,
+                invert = this.target.options.resize.invert,
+                invertible = invert === 'reposition' || invert === 'negate';
+
+            if (edges) {
+                var dx = resizeEvent.dx,
+                    dy = resizeEvent.dy,
+
+                    start      = this.resizeRects.start,
+                    current    = this.resizeRects.current,
+                    restricted = this.resizeRects.restricted,
+                    delta      = this.resizeRects.delta,
+                    previous   = extend(this.resizeRects.previous, restricted),
+
+                    originalEdges = edges;
+
+                // `resize.preserveAspectRatio` takes precedence over `resize.square`
+                if (this.target.options.resize.preserveAspectRatio) {
+                    var resizeStartAspectRatio = this.resizeStartAspectRatio;
+
+                    edges = this.prepared._linkedEdges;
+
+                    if ((originalEdges.left && originalEdges.bottom)
+                        || (originalEdges.right && originalEdges.top)) {
+                        dy = -dx / resizeStartAspectRatio;
+                    }
+                    else if (originalEdges.left || originalEdges.right) { dy = dx / resizeStartAspectRatio; }
+                    else if (originalEdges.top || originalEdges.bottom) { dx = dy * resizeStartAspectRatio; }
+                }
+                else if (this.target.options.resize.square) {
+                    edges = this.prepared._linkedEdges;
+
+                    if ((originalEdges.left && originalEdges.bottom)
+                        || (originalEdges.right && originalEdges.top)) {
+                        dy = -dx;
+                    }
+                    else if (originalEdges.left || originalEdges.right) { dy = dx; }
+                    else if (originalEdges.top || originalEdges.bottom) { dx = dy; }
+                }
+
+                // update the 'current' rect without modifications
+                if (edges.top   ) { current.top    += dy; }
+                if (edges.bottom) { current.bottom += dy; }
+                if (edges.left  ) { current.left   += dx; }
+                if (edges.right ) { current.right  += dx; }
+
+                if (invertible) {
+                    // if invertible, copy the current rect
+                    extend(restricted, current);
+
+                    if (invert === 'reposition') {
+                        // swap edge values if necessary to keep width/height positive
+                        var swap;
+
+                        if (restricted.top > restricted.bottom) {
+                            swap = restricted.top;
+
+                            restricted.top = restricted.bottom;
+                            restricted.bottom = swap;
+                        }
+                        if (restricted.left > restricted.right) {
+                            swap = restricted.left;
+
+                            restricted.left = restricted.right;
+                            restricted.right = swap;
+                        }
+                    }
+                }
+                else {
+                    // if not invertible, restrict to minimum of 0x0 rect
+                    restricted.top    = Math.min(current.top, start.bottom);
+                    restricted.bottom = Math.max(current.bottom, start.top);
+                    restricted.left   = Math.min(current.left, start.right);
+                    restricted.right  = Math.max(current.right, start.left);
+                }
+
+                restricted.width  = restricted.right  - restricted.left;
+                restricted.height = restricted.bottom - restricted.top ;
+
+                for (var edge in restricted) {
+                    delta[edge] = restricted[edge] - previous[edge];
+                }
+
+                resizeEvent.edges = this.prepared.edges;
+                resizeEvent.rect = restricted;
+                resizeEvent.deltaRect = delta;
+            }
+
+            this.target.fire(resizeEvent);
+
+            return resizeEvent;
+        },
+
+        gestureStart: function (event) {
+            var gestureEvent = new InteractEvent(this, event, 'gesture', 'start', this.element);
+
+            gestureEvent.ds = 0;
+
+            this.gesture.startDistance = this.gesture.prevDistance = gestureEvent.distance;
+            this.gesture.startAngle = this.gesture.prevAngle = gestureEvent.angle;
+            this.gesture.scale = 1;
+
+            this.gesturing = true;
+
+            this.target.fire(gestureEvent);
+
+            return gestureEvent;
+        },
+
+        gestureMove: function (event) {
+            if (!this.pointerIds.length) {
+                return this.prevEvent;
+            }
+
+            var gestureEvent;
+
+            gestureEvent = new InteractEvent(this, event, 'gesture', 'move', this.element);
+            gestureEvent.ds = gestureEvent.scale - this.gesture.scale;
+
+            this.target.fire(gestureEvent);
+
+            this.gesture.prevAngle = gestureEvent.angle;
+            this.gesture.prevDistance = gestureEvent.distance;
+
+            if (gestureEvent.scale !== Infinity &&
+                gestureEvent.scale !== null &&
+                gestureEvent.scale !== undefined  &&
+                !isNaN(gestureEvent.scale)) {
+
+                this.gesture.scale = gestureEvent.scale;
+            }
+
+            return gestureEvent;
+        },
+
+        pointerHold: function (pointer, event, eventTarget) {
+            this.collectEventTargets(pointer, event, eventTarget, 'hold');
+        },
+
+        pointerUp: function (pointer, event, eventTarget, curEventTarget) {
+            var pointerIndex = this.mouse? 0 : indexOf(this.pointerIds, getPointerId(pointer));
+
+            clearTimeout(this.holdTimers[pointerIndex]);
+
+            this.collectEventTargets(pointer, event, eventTarget, 'up' );
+            this.collectEventTargets(pointer, event, eventTarget, 'tap');
+
+            this.pointerEnd(pointer, event, eventTarget, curEventTarget);
+
+            this.removePointer(pointer);
+        },
+
+        pointerCancel: function (pointer, event, eventTarget, curEventTarget) {
+            var pointerIndex = this.mouse? 0 : indexOf(this.pointerIds, getPointerId(pointer));
+
+            clearTimeout(this.holdTimers[pointerIndex]);
+
+            this.collectEventTargets(pointer, event, eventTarget, 'cancel');
+            this.pointerEnd(pointer, event, eventTarget, curEventTarget);
+
+            this.removePointer(pointer);
+        },
+
+        // http://www.quirksmode.org/dom/events/click.html
+        // >Events leading to dblclick
+        //
+        // IE8 doesn't fire down event before dblclick.
+        // This workaround tries to fire a tap and doubletap after dblclick
+        ie8Dblclick: function (pointer, event, eventTarget) {
+            if (this.prevTap
+                && event.clientX === this.prevTap.clientX
+                && event.clientY === this.prevTap.clientY
+                && eventTarget   === this.prevTap.target) {
+
+                this.downTargets[0] = eventTarget;
+                this.downTimes[0] = new Date().getTime();
+                this.collectEventTargets(pointer, event, eventTarget, 'tap');
+            }
+        },
+
+        // End interact move events and stop auto-scroll unless inertia is enabled
+        pointerEnd: function (pointer, event, eventTarget, curEventTarget) {
+            var endEvent,
+                target = this.target,
+                options = target && target.options,
+                inertiaOptions = options && this.prepared.name && options[this.prepared.name].inertia,
+                inertiaStatus = this.inertiaStatus;
+
+            if (this.interacting()) {
+
+                if (inertiaStatus.active && !inertiaStatus.ending) { return; }
+
+                var pointerSpeed,
+                    now = new Date().getTime(),
+                    inertiaPossible = false,
+                    inertia = false,
+                    smoothEnd = false,
+                    endSnap = checkSnap(target, this.prepared.name) && options[this.prepared.name].snap.endOnly,
+                    endRestrict = checkRestrict(target, this.prepared.name) && options[this.prepared.name].restrict.endOnly,
+                    dx = 0,
+                    dy = 0,
+                    startEvent;
+
+                if (this.dragging) {
+                    if      (options.drag.axis === 'x' ) { pointerSpeed = Math.abs(this.pointerDelta.client.vx); }
+                    else if (options.drag.axis === 'y' ) { pointerSpeed = Math.abs(this.pointerDelta.client.vy); }
+                    else   /*options.drag.axis === 'xy'*/{ pointerSpeed = this.pointerDelta.client.speed; }
+                }
+                else {
+                    pointerSpeed = this.pointerDelta.client.speed;
+                }
+
+                // check if inertia should be started
+                inertiaPossible = (inertiaOptions && inertiaOptions.enabled
+                                   && this.prepared.name !== 'gesture'
+                                   && event !== inertiaStatus.startEvent);
+
+                inertia = (inertiaPossible
+                           && (now - this.curCoords.timeStamp) < 50
+                           && pointerSpeed > inertiaOptions.minSpeed
+                           && pointerSpeed > inertiaOptions.endSpeed);
+
+                if (inertiaPossible && !inertia && (endSnap || endRestrict)) {
+
+                    var snapRestrict = {};
+
+                    snapRestrict.snap = snapRestrict.restrict = snapRestrict;
+
+                    if (endSnap) {
+                        this.setSnapping(this.curCoords.page, snapRestrict);
+                        if (snapRestrict.locked) {
+                            dx += snapRestrict.dx;
+                            dy += snapRestrict.dy;
+                        }
+                    }
+
+                    if (endRestrict) {
+                        this.setRestriction(this.curCoords.page, snapRestrict);
+                        if (snapRestrict.restricted) {
+                            dx += snapRestrict.dx;
+                            dy += snapRestrict.dy;
+                        }
+                    }
+
+                    if (dx || dy) {
+                        smoothEnd = true;
+                    }
+                }
+
+                if (inertia || smoothEnd) {
+                    copyCoords(inertiaStatus.upCoords, this.curCoords);
+
+                    this.pointers[0] = inertiaStatus.startEvent = startEvent =
+                        new InteractEvent(this, event, this.prepared.name, 'inertiastart', this.element);
+
+                    inertiaStatus.t0 = now;
+
+                    target.fire(inertiaStatus.startEvent);
+
+                    if (inertia) {
+                        inertiaStatus.vx0 = this.pointerDelta.client.vx;
+                        inertiaStatus.vy0 = this.pointerDelta.client.vy;
+                        inertiaStatus.v0 = pointerSpeed;
+
+                        this.calcInertia(inertiaStatus);
+
+                        var page = extend({}, this.curCoords.page),
+                            origin = getOriginXY(target, this.element),
+                            statusObject;
+
+                        page.x = page.x + inertiaStatus.xe - origin.x;
+                        page.y = page.y + inertiaStatus.ye - origin.y;
+
+                        statusObject = {
+                            useStatusXY: true,
+                            x: page.x,
+                            y: page.y,
+                            dx: 0,
+                            dy: 0,
+                            snap: null
+                        };
+
+                        statusObject.snap = statusObject;
+
+                        dx = dy = 0;
+
+                        if (endSnap) {
+                            var snap = this.setSnapping(this.curCoords.page, statusObject);
+
+                            if (snap.locked) {
+                                dx += snap.dx;
+                                dy += snap.dy;
+                            }
+                        }
+
+                        if (endRestrict) {
+                            var restrict = this.setRestriction(this.curCoords.page, statusObject);
+
+                            if (restrict.restricted) {
+                                dx += restrict.dx;
+                                dy += restrict.dy;
+                            }
+                        }
+
+                        inertiaStatus.modifiedXe += dx;
+                        inertiaStatus.modifiedYe += dy;
+
+                        inertiaStatus.i = reqFrame(this.boundInertiaFrame);
+                    }
+                    else {
+                        inertiaStatus.smoothEnd = true;
+                        inertiaStatus.xe = dx;
+                        inertiaStatus.ye = dy;
+
+                        inertiaStatus.sx = inertiaStatus.sy = 0;
+
+                        inertiaStatus.i = reqFrame(this.boundSmoothEndFrame);
+                    }
+
+                    inertiaStatus.active = true;
+                    return;
+                }
+
+                if (endSnap || endRestrict) {
+                    // fire a move event at the snapped coordinates
+                    this.pointerMove(pointer, event, eventTarget, curEventTarget, true);
+                }
+            }
+
+            if (this.dragging) {
+                endEvent = new InteractEvent(this, event, 'drag', 'end', this.element);
+
+                var draggableElement = this.element,
+                    drop = this.getDrop(endEvent, event, draggableElement);
+
+                this.dropTarget = drop.dropzone;
+                this.dropElement = drop.element;
+
+                var dropEvents = this.getDropEvents(event, endEvent);
+
+                if (dropEvents.leave) { this.prevDropTarget.fire(dropEvents.leave); }
+                if (dropEvents.enter) {     this.dropTarget.fire(dropEvents.enter); }
+                if (dropEvents.drop ) {     this.dropTarget.fire(dropEvents.drop ); }
+                if (dropEvents.deactivate) {
+                    this.fireActiveDrops(dropEvents.deactivate);
+                }
+
+                target.fire(endEvent);
+            }
+            else if (this.resizing) {
+                endEvent = new InteractEvent(this, event, 'resize', 'end', this.element);
+                target.fire(endEvent);
+            }
+            else if (this.gesturing) {
+                endEvent = new InteractEvent(this, event, 'gesture', 'end', this.element);
+                target.fire(endEvent);
+            }
+
+            this.stop(event);
+        },
+
+        collectDrops: function (element) {
+            var drops = [],
+                elements = [],
+                i;
+
+            element = element || this.element;
+
+            // collect all dropzones and their elements which qualify for a drop
+            for (i = 0; i < interactables.length; i++) {
+                if (!interactables[i].options.drop.enabled) { continue; }
+
+                var current = interactables[i],
+                    accept = current.options.drop.accept;
+
+                // test the draggable element against the dropzone's accept setting
+                if ((isElement(accept) && accept !== element)
+                    || (isString(accept)
+                        && !matchesSelector(element, accept))) {
+
+                    continue;
+                }
+
+                // query for new elements if necessary
+                var dropElements = current.selector? current._context.querySelectorAll(current.selector) : [current._element];
+
+                for (var j = 0, len = dropElements.length; j < len; j++) {
+                    var currentElement = dropElements[j];
+
+                    if (currentElement === element) {
+                        continue;
+                    }
+
+                    drops.push(current);
+                    elements.push(currentElement);
+                }
+            }
+
+            return {
+                dropzones: drops,
+                elements: elements
+            };
+        },
+
+        fireActiveDrops: function (event) {
+            var i,
+                current,
+                currentElement,
+                prevElement;
+
+            // loop through all active dropzones and trigger event
+            for (i = 0; i < this.activeDrops.dropzones.length; i++) {
+                current = this.activeDrops.dropzones[i];
+                currentElement = this.activeDrops.elements [i];
+
+                // prevent trigger of duplicate events on same element
+                if (currentElement !== prevElement) {
+                    // set current element as event target
+                    event.target = currentElement;
+                    current.fire(event);
+                }
+                prevElement = currentElement;
+            }
+        },
+
+        // Collect a new set of possible drops and save them in activeDrops.
+        // setActiveDrops should always be called when a drag has just started or a
+        // drag event happens while dynamicDrop is true
+        setActiveDrops: function (dragElement) {
+            // get dropzones and their elements that could receive the draggable
+            var possibleDrops = this.collectDrops(dragElement, true);
+
+            this.activeDrops.dropzones = possibleDrops.dropzones;
+            this.activeDrops.elements  = possibleDrops.elements;
+            this.activeDrops.rects     = [];
+
+            for (var i = 0; i < this.activeDrops.dropzones.length; i++) {
+                this.activeDrops.rects[i] = this.activeDrops.dropzones[i].getRect(this.activeDrops.elements[i]);
+            }
+        },
+
+        getDrop: function (dragEvent, event, dragElement) {
+            var validDrops = [];
+
+            if (dynamicDrop) {
+                this.setActiveDrops(dragElement);
+            }
+
+            // collect all dropzones and their elements which qualify for a drop
+            for (var j = 0; j < this.activeDrops.dropzones.length; j++) {
+                var current        = this.activeDrops.dropzones[j],
+                    currentElement = this.activeDrops.elements [j],
+                    rect           = this.activeDrops.rects    [j];
+
+                validDrops.push(current.dropCheck(dragEvent, event, this.target, dragElement, currentElement, rect)
+                                ? currentElement
+                                : null);
+            }
+
+            // get the most appropriate dropzone based on DOM depth and order
+            var dropIndex = indexOfDeepestElement(validDrops),
+                dropzone  = this.activeDrops.dropzones[dropIndex] || null,
+                element   = this.activeDrops.elements [dropIndex] || null;
+
+            return {
+                dropzone: dropzone,
+                element: element
+            };
+        },
+
+        getDropEvents: function (pointerEvent, dragEvent) {
+            var dropEvents = {
+                enter     : null,
+                leave     : null,
+                activate  : null,
+                deactivate: null,
+                move      : null,
+                drop      : null
+            };
+
+            if (this.dropElement !== this.prevDropElement) {
+                // if there was a prevDropTarget, create a dragleave event
+                if (this.prevDropTarget) {
+                    dropEvents.leave = {
+                        target       : this.prevDropElement,
+                        dropzone     : this.prevDropTarget,
+                        relatedTarget: dragEvent.target,
+                        draggable    : dragEvent.interactable,
+                        dragEvent    : dragEvent,
+                        interaction  : this,
+                        timeStamp    : dragEvent.timeStamp,
+                        type         : 'dragleave'
+                    };
+
+                    dragEvent.dragLeave = this.prevDropElement;
+                    dragEvent.prevDropzone = this.prevDropTarget;
+                }
+                // if the dropTarget is not null, create a dragenter event
+                if (this.dropTarget) {
+                    dropEvents.enter = {
+                        target       : this.dropElement,
+                        dropzone     : this.dropTarget,
+                        relatedTarget: dragEvent.target,
+                        draggable    : dragEvent.interactable,
+                        dragEvent    : dragEvent,
+                        interaction  : this,
+                        timeStamp    : dragEvent.timeStamp,
+                        type         : 'dragenter'
+                    };
+
+                    dragEvent.dragEnter = this.dropElement;
+                    dragEvent.dropzone = this.dropTarget;
+                }
+            }
+
+            if (dragEvent.type === 'dragend' && this.dropTarget) {
+                dropEvents.drop = {
+                    target       : this.dropElement,
+                    dropzone     : this.dropTarget,
+                    relatedTarget: dragEvent.target,
+                    draggable    : dragEvent.interactable,
+                    dragEvent    : dragEvent,
+                    interaction  : this,
+                    timeStamp    : dragEvent.timeStamp,
+                    type         : 'drop'
+                };
+
+                dragEvent.dropzone = this.dropTarget;
+            }
+            if (dragEvent.type === 'dragstart') {
+                dropEvents.activate = {
+                    target       : null,
+                    dropzone     : null,
+                    relatedTarget: dragEvent.target,
+                    draggable    : dragEvent.interactable,
+                    dragEvent    : dragEvent,
+                    interaction  : this,
+                    timeStamp    : dragEvent.timeStamp,
+                    type         : 'dropactivate'
+                };
+            }
+            if (dragEvent.type === 'dragend') {
+                dropEvents.deactivate = {
+                    target       : null,
+                    dropzone     : null,
+                    relatedTarget: dragEvent.target,
+                    draggable    : dragEvent.interactable,
+                    dragEvent    : dragEvent,
+                    interaction  : this,
+                    timeStamp    : dragEvent.timeStamp,
+                    type         : 'dropdeactivate'
+                };
+            }
+            if (dragEvent.type === 'dragmove' && this.dropTarget) {
+                dropEvents.move = {
+                    target       : this.dropElement,
+                    dropzone     : this.dropTarget,
+                    relatedTarget: dragEvent.target,
+                    draggable    : dragEvent.interactable,
+                    dragEvent    : dragEvent,
+                    interaction  : this,
+                    dragmove     : dragEvent,
+                    timeStamp    : dragEvent.timeStamp,
+                    type         : 'dropmove'
+                };
+                dragEvent.dropzone = this.dropTarget;
+            }
+
+            return dropEvents;
+        },
+
+        currentAction: function () {
+            return (this.dragging && 'drag') || (this.resizing && 'resize') || (this.gesturing && 'gesture') || null;
+        },
+
+        interacting: function () {
+            return this.dragging || this.resizing || this.gesturing;
+        },
+
+        clearTargets: function () {
+            this.target = this.element = null;
+
+            this.dropTarget = this.dropElement = this.prevDropTarget = this.prevDropElement = null;
+        },
+
+        stop: function (event) {
+            if (this.interacting()) {
+                autoScroll.stop();
+                this.matches = [];
+                this.matchElements = [];
+
+                var target = this.target;
+
+                if (target.options.styleCursor) {
+                    target._doc.documentElement.style.cursor = '';
+                }
+
+                // prevent Default only if were previously interacting
+                if (event && isFunction(event.preventDefault)) {
+                    this.checkAndPreventDefault(event, target, this.element);
+                }
+
+                if (this.dragging) {
+                    this.activeDrops.dropzones = this.activeDrops.elements = this.activeDrops.rects = null;
+                }
+            }
+
+            this.clearTargets();
+
+            this.pointerIsDown = this.snapStatus.locked = this.dragging = this.resizing = this.gesturing = false;
+            this.prepared.name = this.prevEvent = null;
+            this.inertiaStatus.resumeDx = this.inertiaStatus.resumeDy = 0;
+
+            // remove pointers if their ID isn't in this.pointerIds
+            for (var i = 0; i < this.pointers.length; i++) {
+                if (indexOf(this.pointerIds, getPointerId(this.pointers[i])) === -1) {
+                    this.pointers.splice(i, 1);
+                }
+            }
+        },
+
+        inertiaFrame: function () {
+            var inertiaStatus = this.inertiaStatus,
+                options = this.target.options[this.prepared.name].inertia,
+                lambda = options.resistance,
+                t = new Date().getTime() / 1000 - inertiaStatus.t0;
+
+            if (t < inertiaStatus.te) {
+
+                var progress =  1 - (Math.exp(-lambda * t) - inertiaStatus.lambda_v0) / inertiaStatus.one_ve_v0;
+
+                if (inertiaStatus.modifiedXe === inertiaStatus.xe && inertiaStatus.modifiedYe === inertiaStatus.ye) {
+                    inertiaStatus.sx = inertiaStatus.xe * progress;
+                    inertiaStatus.sy = inertiaStatus.ye * progress;
+                }
+                else {
+                    var quadPoint = getQuadraticCurvePoint(
+                            0, 0,
+                            inertiaStatus.xe, inertiaStatus.ye,
+                            inertiaStatus.modifiedXe, inertiaStatus.modifiedYe,
+                            progress);
+
+                    inertiaStatus.sx = quadPoint.x;
+                    inertiaStatus.sy = quadPoint.y;
+                }
+
+                this.pointerMove(inertiaStatus.startEvent, inertiaStatus.startEvent);
+
+                inertiaStatus.i = reqFrame(this.boundInertiaFrame);
+            }
+            else {
+                inertiaStatus.ending = true;
+
+                inertiaStatus.sx = inertiaStatus.modifiedXe;
+                inertiaStatus.sy = inertiaStatus.modifiedYe;
+
+                this.pointerMove(inertiaStatus.startEvent, inertiaStatus.startEvent);
+                this.pointerEnd(inertiaStatus.startEvent, inertiaStatus.startEvent);
+
+                inertiaStatus.active = inertiaStatus.ending = false;
+            }
+        },
+
+        smoothEndFrame: function () {
+            var inertiaStatus = this.inertiaStatus,
+                t = new Date().getTime() - inertiaStatus.t0,
+                duration = this.target.options[this.prepared.name].inertia.smoothEndDuration;
+
+            if (t < duration) {
+                inertiaStatus.sx = easeOutQuad(t, 0, inertiaStatus.xe, duration);
+                inertiaStatus.sy = easeOutQuad(t, 0, inertiaStatus.ye, duration);
+
+                this.pointerMove(inertiaStatus.startEvent, inertiaStatus.startEvent);
+
+                inertiaStatus.i = reqFrame(this.boundSmoothEndFrame);
+            }
+            else {
+                inertiaStatus.ending = true;
+
+                inertiaStatus.sx = inertiaStatus.xe;
+                inertiaStatus.sy = inertiaStatus.ye;
+
+                this.pointerMove(inertiaStatus.startEvent, inertiaStatus.startEvent);
+                this.pointerEnd(inertiaStatus.startEvent, inertiaStatus.startEvent);
+
+                inertiaStatus.smoothEnd =
+                  inertiaStatus.active = inertiaStatus.ending = false;
+            }
+        },
+
+        addPointer: function (pointer) {
+            var id = getPointerId(pointer),
+                index = this.mouse? 0 : indexOf(this.pointerIds, id);
+
+            if (index === -1) {
+                index = this.pointerIds.length;
+            }
+
+            this.pointerIds[index] = id;
+            this.pointers[index] = pointer;
+
+            return index;
+        },
+
+        removePointer: function (pointer) {
+            var id = getPointerId(pointer),
+                index = this.mouse? 0 : indexOf(this.pointerIds, id);
+
+            if (index === -1) { return; }
+
+            this.pointers   .splice(index, 1);
+            this.pointerIds .splice(index, 1);
+            this.downTargets.splice(index, 1);
+            this.downTimes  .splice(index, 1);
+            this.holdTimers .splice(index, 1);
+        },
+
+        recordPointer: function (pointer) {
+            var index = this.mouse? 0: indexOf(this.pointerIds, getPointerId(pointer));
+
+            if (index === -1) { return; }
+
+            this.pointers[index] = pointer;
+        },
+
+        collectEventTargets: function (pointer, event, eventTarget, eventType) {
+            var pointerIndex = this.mouse? 0 : indexOf(this.pointerIds, getPointerId(pointer));
+
+            // do not fire a tap event if the pointer was moved before being lifted
+            if (eventType === 'tap' && (this.pointerWasMoved
+                // or if the pointerup target is different to the pointerdown target
+                || !(this.downTargets[pointerIndex] && this.downTargets[pointerIndex] === eventTarget))) {
+                return;
+            }
+
+            var targets = [],
+                elements = [],
+                element = eventTarget;
+
+            function collectSelectors (interactable, selector, context) {
+                var els = ie8MatchesSelector
+                        ? context.querySelectorAll(selector)
+                        : undefined;
+
+                if (interactable._iEvents[eventType]
+                    && isElement(element)
+                    && inContext(interactable, element)
+                    && !testIgnore(interactable, element, eventTarget)
+                    && testAllow(interactable, element, eventTarget)
+                    && matchesSelector(element, selector, els)) {
+
+                    targets.push(interactable);
+                    elements.push(element);
+                }
+            }
+
+            while (element) {
+                if (interact.isSet(element) && interact(element)._iEvents[eventType]) {
+                    targets.push(interact(element));
+                    elements.push(element);
+                }
+
+                interactables.forEachSelector(collectSelectors);
+
+                element = parentElement(element);
+            }
+
+            // create the tap event even if there are no listeners so that
+            // doubletap can still be created and fired
+            if (targets.length || eventType === 'tap') {
+                this.firePointers(pointer, event, eventTarget, targets, elements, eventType);
+            }
+        },
+
+        firePointers: function (pointer, event, eventTarget, targets, elements, eventType) {
+            var pointerIndex = this.mouse? 0 : indexOf(this.pointerIds, getPointerId(pointer)),
+                pointerEvent = {},
+                i,
+                // for tap events
+                interval, createNewDoubleTap;
+
+            // if it's a doubletap then the event properties would have been
+            // copied from the tap event and provided as the pointer argument
+            if (eventType === 'doubletap') {
+                pointerEvent = pointer;
+            }
+            else {
+                pointerExtend(pointerEvent, event);
+                if (event !== pointer) {
+                    pointerExtend(pointerEvent, pointer);
+                }
+
+                pointerEvent.preventDefault           = preventOriginalDefault;
+                pointerEvent.stopPropagation          = InteractEvent.prototype.stopPropagation;
+                pointerEvent.stopImmediatePropagation = InteractEvent.prototype.stopImmediatePropagation;
+                pointerEvent.interaction              = this;
+
+                pointerEvent.timeStamp       = new Date().getTime();
+                pointerEvent.originalEvent   = event;
+                pointerEvent.originalPointer = pointer;
+                pointerEvent.type            = eventType;
+                pointerEvent.pointerId       = getPointerId(pointer);
+                pointerEvent.pointerType     = this.mouse? 'mouse' : !supportsPointerEvent? 'touch'
+                                                    : isString(pointer.pointerType)
+                                                        ? pointer.pointerType
+                                                        : [,,'touch', 'pen', 'mouse'][pointer.pointerType];
+            }
+
+            if (eventType === 'tap') {
+                pointerEvent.dt = pointerEvent.timeStamp - this.downTimes[pointerIndex];
+
+                interval = pointerEvent.timeStamp - this.tapTime;
+                createNewDoubleTap = !!(this.prevTap && this.prevTap.type !== 'doubletap'
+                       && this.prevTap.target === pointerEvent.target
+                       && interval < 500);
+
+                pointerEvent.double = createNewDoubleTap;
+
+                this.tapTime = pointerEvent.timeStamp;
+            }
+
+            for (i = 0; i < targets.length; i++) {
+                pointerEvent.currentTarget = elements[i];
+                pointerEvent.interactable = targets[i];
+                targets[i].fire(pointerEvent);
+
+                if (pointerEvent.immediatePropagationStopped
+                    ||(pointerEvent.propagationStopped && elements[i + 1] !== pointerEvent.currentTarget)) {
+                    break;
+                }
+            }
+
+            if (createNewDoubleTap) {
+                var doubleTap = {};
+
+                extend(doubleTap, pointerEvent);
+
+                doubleTap.dt   = interval;
+                doubleTap.type = 'doubletap';
+
+                this.collectEventTargets(doubleTap, event, eventTarget, 'doubletap');
+
+                this.prevTap = doubleTap;
+            }
+            else if (eventType === 'tap') {
+                this.prevTap = pointerEvent;
+            }
+        },
+
+        validateSelector: function (pointer, event, matches, matchElements) {
+            for (var i = 0, len = matches.length; i < len; i++) {
+                var match = matches[i],
+                    matchElement = matchElements[i],
+                    action = validateAction(match.getAction(pointer, event, this, matchElement), match);
+
+                if (action && withinInteractionLimit(match, matchElement, action)) {
+                    this.target = match;
+                    this.element = matchElement;
+
+                    return action;
+                }
+            }
+        },
+
+        setSnapping: function (pageCoords, status) {
+            var snap = this.target.options[this.prepared.name].snap,
+                targets = [],
+                target,
+                page,
+                i;
+
+            status = status || this.snapStatus;
+
+            if (status.useStatusXY) {
+                page = { x: status.x, y: status.y };
+            }
+            else {
+                var origin = getOriginXY(this.target, this.element);
+
+                page = extend({}, pageCoords);
+
+                page.x -= origin.x;
+                page.y -= origin.y;
+            }
+
+            status.realX = page.x;
+            status.realY = page.y;
+
+            page.x = page.x - this.inertiaStatus.resumeDx;
+            page.y = page.y - this.inertiaStatus.resumeDy;
+
+            var len = snap.targets? snap.targets.length : 0;
+
+            for (var relIndex = 0; relIndex < this.snapOffsets.length; relIndex++) {
+                var relative = {
+                    x: page.x - this.snapOffsets[relIndex].x,
+                    y: page.y - this.snapOffsets[relIndex].y
+                };
+
+                for (i = 0; i < len; i++) {
+                    if (isFunction(snap.targets[i])) {
+                        target = snap.targets[i](relative.x, relative.y, this);
+                    }
+                    else {
+                        target = snap.targets[i];
+                    }
+
+                    if (!target) { continue; }
+
+                    targets.push({
+                        x: isNumber(target.x) ? (target.x + this.snapOffsets[relIndex].x) : relative.x,
+                        y: isNumber(target.y) ? (target.y + this.snapOffsets[relIndex].y) : relative.y,
+
+                        range: isNumber(target.range)? target.range: snap.range
+                    });
+                }
+            }
+
+            var closest = {
+                    target: null,
+                    inRange: false,
+                    distance: 0,
+                    range: 0,
+                    dx: 0,
+                    dy: 0
+                };
+
+            for (i = 0, len = targets.length; i < len; i++) {
+                target = targets[i];
+
+                var range = target.range,
+                    dx = target.x - page.x,
+                    dy = target.y - page.y,
+                    distance = hypot(dx, dy),
+                    inRange = distance <= range;
+
+                // Infinite targets count as being out of range
+                // compared to non infinite ones that are in range
+                if (range === Infinity && closest.inRange && closest.range !== Infinity) {
+                    inRange = false;
+                }
+
+                if (!closest.target || (inRange
+                    // is the closest target in range?
+                    ? (closest.inRange && range !== Infinity
+                        // the pointer is relatively deeper in this target
+                        ? distance / range < closest.distance / closest.range
+                        // this target has Infinite range and the closest doesn't
+                        : (range === Infinity && closest.range !== Infinity)
+                            // OR this target is closer that the previous closest
+                            || distance < closest.distance)
+                    // The other is not in range and the pointer is closer to this target
+                    : (!closest.inRange && distance < closest.distance))) {
+
+                    if (range === Infinity) {
+                        inRange = true;
+                    }
+
+                    closest.target = target;
+                    closest.distance = distance;
+                    closest.range = range;
+                    closest.inRange = inRange;
+                    closest.dx = dx;
+                    closest.dy = dy;
+
+                    status.range = range;
+                }
+            }
+
+            var snapChanged;
+
+            if (closest.target) {
+                snapChanged = (status.snappedX !== closest.target.x || status.snappedY !== closest.target.y);
+
+                status.snappedX = closest.target.x;
+                status.snappedY = closest.target.y;
+            }
+            else {
+                snapChanged = true;
+
+                status.snappedX = NaN;
+                status.snappedY = NaN;
+            }
+
+            status.dx = closest.dx;
+            status.dy = closest.dy;
+
+            status.changed = (snapChanged || (closest.inRange && !status.locked));
+            status.locked = closest.inRange;
+
+            return status;
+        },
+
+        setRestriction: function (pageCoords, status) {
+            var target = this.target,
+                restrict = target && target.options[this.prepared.name].restrict,
+                restriction = restrict && restrict.restriction,
+                page;
+
+            if (!restriction) {
+                return status;
+            }
+
+            status = status || this.restrictStatus;
+
+            page = status.useStatusXY
+                    ? page = { x: status.x, y: status.y }
+                    : page = extend({}, pageCoords);
+
+            if (status.snap && status.snap.locked) {
+                page.x += status.snap.dx || 0;
+                page.y += status.snap.dy || 0;
+            }
+
+            page.x -= this.inertiaStatus.resumeDx;
+            page.y -= this.inertiaStatus.resumeDy;
+
+            status.dx = 0;
+            status.dy = 0;
+            status.restricted = false;
+
+            var rect, restrictedX, restrictedY;
+
+            if (isString(restriction)) {
+                if (restriction === 'parent') {
+                    restriction = parentElement(this.element);
+                }
+                else if (restriction === 'self') {
+                    restriction = target.getRect(this.element);
+                }
+                else {
+                    restriction = closest(this.element, restriction);
+                }
+
+                if (!restriction) { return status; }
+            }
+
+            if (isFunction(restriction)) {
+                restriction = restriction(page.x, page.y, this.element);
+            }
+
+            if (isElement(restriction)) {
+                restriction = getElementRect(restriction);
+            }
+
+            rect = restriction;
+
+            if (!restriction) {
+                restrictedX = page.x;
+                restrictedY = page.y;
+            }
+            // object is assumed to have
+            // x, y, width, height or
+            // left, top, right, bottom
+            else if ('x' in restriction && 'y' in restriction) {
+                restrictedX = Math.max(Math.min(rect.x + rect.width  - this.restrictOffset.right , page.x), rect.x + this.restrictOffset.left);
+                restrictedY = Math.max(Math.min(rect.y + rect.height - this.restrictOffset.bottom, page.y), rect.y + this.restrictOffset.top );
+            }
+            else {
+                restrictedX = Math.max(Math.min(rect.right  - this.restrictOffset.right , page.x), rect.left + this.restrictOffset.left);
+                restrictedY = Math.max(Math.min(rect.bottom - this.restrictOffset.bottom, page.y), rect.top  + this.restrictOffset.top );
+            }
+
+            status.dx = restrictedX - page.x;
+            status.dy = restrictedY - page.y;
+
+            status.changed = status.restrictedX !== restrictedX || status.restrictedY !== restrictedY;
+            status.restricted = !!(status.dx || status.dy);
+
+            status.restrictedX = restrictedX;
+            status.restrictedY = restrictedY;
+
+            return status;
+        },
+
+        checkAndPreventDefault: function (event, interactable, element) {
+            if (!(interactable = interactable || this.target)) { return; }
+
+            var options = interactable.options,
+                prevent = options.preventDefault;
+
+            if (prevent === 'auto' && element && !/^(input|select|textarea)$/i.test(event.target.nodeName)) {
+                // do not preventDefault on pointerdown if the prepared action is a drag
+                // and dragging can only start from a certain direction - this allows
+                // a touch to pan the viewport if a drag isn't in the right direction
+                if (/down|start/i.test(event.type)
+                    && this.prepared.name === 'drag' && options.drag.axis !== 'xy') {
+
+                    return;
+                }
+
+                // with manualStart, only preventDefault while interacting
+                if (options[this.prepared.name] && options[this.prepared.name].manualStart
+                    && !this.interacting()) {
+                    return;
+                }
+
+                event.preventDefault();
+                return;
+            }
+
+            if (prevent === 'always') {
+                event.preventDefault();
+                return;
+            }
+        },
+
+        calcInertia: function (status) {
+            var inertiaOptions = this.target.options[this.prepared.name].inertia,
+                lambda = inertiaOptions.resistance,
+                inertiaDur = -Math.log(inertiaOptions.endSpeed / status.v0) / lambda;
+
+            status.x0 = this.prevEvent.pageX;
+            status.y0 = this.prevEvent.pageY;
+            status.t0 = status.startEvent.timeStamp / 1000;
+            status.sx = status.sy = 0;
+
+            status.modifiedXe = status.xe = (status.vx0 - inertiaDur) / lambda;
+            status.modifiedYe = status.ye = (status.vy0 - inertiaDur) / lambda;
+            status.te = inertiaDur;
+
+            status.lambda_v0 = lambda / status.v0;
+            status.one_ve_v0 = 1 - inertiaOptions.endSpeed / status.v0;
+        },
+
+        autoScrollMove: function (pointer) {
+            if (!(this.interacting()
+                && checkAutoScroll(this.target, this.prepared.name))) {
+                return;
+            }
+
+            if (this.inertiaStatus.active) {
+                autoScroll.x = autoScroll.y = 0;
+                return;
+            }
+
+            var top,
+                right,
+                bottom,
+                left,
+                options = this.target.options[this.prepared.name].autoScroll,
+                container = options.container || getWindow(this.element);
+
+            if (isWindow(container)) {
+                left   = pointer.clientX < autoScroll.margin;
+                top    = pointer.clientY < autoScroll.margin;
+                right  = pointer.clientX > container.innerWidth  - autoScroll.margin;
+                bottom = pointer.clientY > container.innerHeight - autoScroll.margin;
+            }
+            else {
+                var rect = getElementClientRect(container);
+
+                left   = pointer.clientX < rect.left   + autoScroll.margin;
+                top    = pointer.clientY < rect.top    + autoScroll.margin;
+                right  = pointer.clientX > rect.right  - autoScroll.margin;
+                bottom = pointer.clientY > rect.bottom - autoScroll.margin;
+            }
+
+            autoScroll.x = (right ? 1: left? -1: 0);
+            autoScroll.y = (bottom? 1:  top? -1: 0);
+
+            if (!autoScroll.isScrolling) {
+                // set the autoScroll properties to those of the target
+                autoScroll.margin = options.margin;
+                autoScroll.speed  = options.speed;
+
+                autoScroll.start(this);
+            }
+        },
+
+        _updateEventTargets: function (target, currentTarget) {
+            this._eventTarget    = target;
+            this._curEventTarget = currentTarget;
+        }
+
+    };
+
+    function getInteractionFromPointer (pointer, eventType, eventTarget) {
+        var i = 0, len = interactions.length,
+            mouseEvent = (/mouse/i.test(pointer.pointerType || eventType)
+                          // MSPointerEvent.MSPOINTER_TYPE_MOUSE
+                          || pointer.pointerType === 4),
+            interaction;
+
+        var id = getPointerId(pointer);
+
+        // try to resume inertia with a new pointer
+        if (/down|start/i.test(eventType)) {
+            for (i = 0; i < len; i++) {
+                interaction = interactions[i];
+
+                var element = eventTarget;
+
+                if (interaction.inertiaStatus.active && interaction.target.options[interaction.prepared.name].inertia.allowResume
+                    && (interaction.mouse === mouseEvent)) {
+                    while (element) {
+                        // if the element is the interaction element
+                        if (element === interaction.element) {
+                            return interaction;
+                        }
+                        element = parentElement(element);
+                    }
+                }
+            }
+        }
+
+        // if it's a mouse interaction
+        if (mouseEvent || !(supportsTouch || supportsPointerEvent)) {
+
+            // find a mouse interaction that's not in inertia phase
+            for (i = 0; i < len; i++) {
+                if (interactions[i].mouse && !interactions[i].inertiaStatus.active) {
+                    return interactions[i];
+                }
+            }
+
+            // find any interaction specifically for mouse.
+            // if the eventType is a mousedown, and inertia is active
+            // ignore the interaction
+            for (i = 0; i < len; i++) {
+                if (interactions[i].mouse && !(/down/.test(eventType) && interactions[i].inertiaStatus.active)) {
+                    return interaction;
+                }
+            }
+
+            // create a new interaction for mouse
+            interaction = new Interaction();
+            interaction.mouse = true;
+
+            return interaction;
+        }
+
+        // get interaction that has this pointer
+        for (i = 0; i < len; i++) {
+            if (contains(interactions[i].pointerIds, id)) {
+                return interactions[i];
+            }
+        }
+
+        // at this stage, a pointerUp should not return an interaction
+        if (/up|end|out/i.test(eventType)) {
+            return null;
+        }
+
+        // get first idle interaction
+        for (i = 0; i < len; i++) {
+            interaction = interactions[i];
+
+            if ((!interaction.prepared.name || (interaction.target.options.gesture.enabled))
+                && !interaction.interacting()
+                && !(!mouseEvent && interaction.mouse)) {
+
+                return interaction;
+            }
+        }
+
+        return new Interaction();
+    }
+
+    function doOnInteractions (method) {
+        return (function (event) {
+            var interaction,
+                eventTarget = getActualElement(event.path
+                                               ? event.path[0]
+                                               : event.target),
+                curEventTarget = getActualElement(event.currentTarget),
+                i;
+
+            if (supportsTouch && /touch/.test(event.type)) {
+                prevTouchTime = new Date().getTime();
+
+                for (i = 0; i < event.changedTouches.length; i++) {
+                    var pointer = event.changedTouches[i];
+
+                    interaction = getInteractionFromPointer(pointer, event.type, eventTarget);
+
+                    if (!interaction) { continue; }
+
+                    interaction._updateEventTargets(eventTarget, curEventTarget);
+
+                    interaction[method](pointer, event, eventTarget, curEventTarget);
+                }
+            }
+            else {
+                if (!supportsPointerEvent && /mouse/.test(event.type)) {
+                    // ignore mouse events while touch interactions are active
+                    for (i = 0; i < interactions.length; i++) {
+                        if (!interactions[i].mouse && interactions[i].pointerIsDown) {
+                            return;
+                        }
+                    }
+
+                    // try to ignore mouse events that are simulated by the browser
+                    // after a touch event
+                    if (new Date().getTime() - prevTouchTime < 500) {
+                        return;
+                    }
+                }
+
+                interaction = getInteractionFromPointer(event, event.type, eventTarget);
+
+                if (!interaction) { return; }
+
+                interaction._updateEventTargets(eventTarget, curEventTarget);
+
+                interaction[method](event, event, eventTarget, curEventTarget);
+            }
+        });
+    }
+
+    function InteractEvent (interaction, event, action, phase, element, related) {
+        var client,
+            page,
+            target      = interaction.target,
+            snapStatus  = interaction.snapStatus,
+            restrictStatus  = interaction.restrictStatus,
+            pointers    = interaction.pointers,
+            deltaSource = (target && target.options || defaultOptions).deltaSource,
+            sourceX     = deltaSource + 'X',
+            sourceY     = deltaSource + 'Y',
+            options     = target? target.options: defaultOptions,
+            origin      = getOriginXY(target, element),
+            starting    = phase === 'start',
+            ending      = phase === 'end',
+            coords      = starting? interaction.startCoords : interaction.curCoords;
+
+        element = element || interaction.element;
+
+        page   = extend({}, coords.page);
+        client = extend({}, coords.client);
+
+        page.x -= origin.x;
+        page.y -= origin.y;
+
+        client.x -= origin.x;
+        client.y -= origin.y;
+
+        var relativePoints = options[action].snap && options[action].snap.relativePoints ;
+
+        if (checkSnap(target, action) && !(starting && relativePoints && relativePoints.length)) {
+            this.snap = {
+                range  : snapStatus.range,
+                locked : snapStatus.locked,
+                x      : snapStatus.snappedX,
+                y      : snapStatus.snappedY,
+                realX  : snapStatus.realX,
+                realY  : snapStatus.realY,
+                dx     : snapStatus.dx,
+                dy     : snapStatus.dy
+            };
+
+            if (snapStatus.locked) {
+                page.x += snapStatus.dx;
+                page.y += snapStatus.dy;
+                client.x += snapStatus.dx;
+                client.y += snapStatus.dy;
+            }
+        }
+
+        if (checkRestrict(target, action) && !(starting && options[action].restrict.elementRect) && restrictStatus.restricted) {
+            page.x += restrictStatus.dx;
+            page.y += restrictStatus.dy;
+            client.x += restrictStatus.dx;
+            client.y += restrictStatus.dy;
+
+            this.restrict = {
+                dx: restrictStatus.dx,
+                dy: restrictStatus.dy
+            };
+        }
+
+        this.pageX     = page.x;
+        this.pageY     = page.y;
+        this.clientX   = client.x;
+        this.clientY   = client.y;
+
+        this.x0        = interaction.startCoords.page.x - origin.x;
+        this.y0        = interaction.startCoords.page.y - origin.y;
+        this.clientX0  = interaction.startCoords.client.x - origin.x;
+        this.clientY0  = interaction.startCoords.client.y - origin.y;
+        this.ctrlKey   = event.ctrlKey;
+        this.altKey    = event.altKey;
+        this.shiftKey  = event.shiftKey;
+        this.metaKey   = event.metaKey;
+        this.button    = event.button;
+        this.buttons   = event.buttons;
+        this.target    = element;
+        this.t0        = interaction.downTimes[0];
+        this.type      = action + (phase || '');
+
+        this.interaction = interaction;
+        this.interactable = target;
+
+        var inertiaStatus = interaction.inertiaStatus;
+
+        if (inertiaStatus.active) {
+            this.detail = 'inertia';
+        }
+
+        if (related) {
+            this.relatedTarget = related;
+        }
+
+        // end event dx, dy is difference between start and end points
+        if (ending) {
+            if (deltaSource === 'client') {
+                this.dx = client.x - interaction.startCoords.client.x;
+                this.dy = client.y - interaction.startCoords.client.y;
+            }
+            else {
+                this.dx = page.x - interaction.startCoords.page.x;
+                this.dy = page.y - interaction.startCoords.page.y;
+            }
+        }
+        else if (starting) {
+            this.dx = 0;
+            this.dy = 0;
+        }
+        // copy properties from previousmove if starting inertia
+        else if (phase === 'inertiastart') {
+            this.dx = interaction.prevEvent.dx;
+            this.dy = interaction.prevEvent.dy;
+        }
+        else {
+            if (deltaSource === 'client') {
+                this.dx = client.x - interaction.prevEvent.clientX;
+                this.dy = client.y - interaction.prevEvent.clientY;
+            }
+            else {
+                this.dx = page.x - interaction.prevEvent.pageX;
+                this.dy = page.y - interaction.prevEvent.pageY;
+            }
+        }
+        if (interaction.prevEvent && interaction.prevEvent.detail === 'inertia'
+            && !inertiaStatus.active
+            && options[action].inertia && options[action].inertia.zeroResumeDelta) {
+
+            inertiaStatus.resumeDx += this.dx;
+            inertiaStatus.resumeDy += this.dy;
+
+            this.dx = this.dy = 0;
+        }
+
+        if (action === 'resize' && interaction.resizeAxes) {
+            if (options.resize.square) {
+                if (interaction.resizeAxes === 'y') {
+                    this.dx = this.dy;
+                }
+                else {
+                    this.dy = this.dx;
+                }
+                this.axes = 'xy';
+            }
+            else {
+                this.axes = interaction.resizeAxes;
+
+                if (interaction.resizeAxes === 'x') {
+                    this.dy = 0;
+                }
+                else if (interaction.resizeAxes === 'y') {
+                    this.dx = 0;
+                }
+            }
+        }
+        else if (action === 'gesture') {
+            this.touches = [pointers[0], pointers[1]];
+
+            if (starting) {
+                this.distance = touchDistance(pointers, deltaSource);
+                this.box      = touchBBox(pointers);
+                this.scale    = 1;
+                this.ds       = 0;
+                this.angle    = touchAngle(pointers, undefined, deltaSource);
+                this.da       = 0;
+            }
+            else if (ending || event instanceof InteractEvent) {
+                this.distance = interaction.prevEvent.distance;
+                this.box      = interaction.prevEvent.box;
+                this.scale    = interaction.prevEvent.scale;
+                this.ds       = this.scale - 1;
+                this.angle    = interaction.prevEvent.angle;
+                this.da       = this.angle - interaction.gesture.startAngle;
+            }
+            else {
+                this.distance = touchDistance(pointers, deltaSource);
+                this.box      = touchBBox(pointers);
+                this.scale    = this.distance / interaction.gesture.startDistance;
+                this.angle    = touchAngle(pointers, interaction.gesture.prevAngle, deltaSource);
+
+                this.ds = this.scale - interaction.gesture.prevScale;
+                this.da = this.angle - interaction.gesture.prevAngle;
+            }
+        }
+
+        if (starting) {
+            this.timeStamp = interaction.downTimes[0];
+            this.dt        = 0;
+            this.duration  = 0;
+            this.speed     = 0;
+            this.velocityX = 0;
+            this.velocityY = 0;
+        }
+        else if (phase === 'inertiastart') {
+            this.timeStamp = interaction.prevEvent.timeStamp;
+            this.dt        = interaction.prevEvent.dt;
+            this.duration  = interaction.prevEvent.duration;
+            this.speed     = interaction.prevEvent.speed;
+            this.velocityX = interaction.prevEvent.velocityX;
+            this.velocityY = interaction.prevEvent.velocityY;
+        }
+        else {
+            this.timeStamp = new Date().getTime();
+            this.dt        = this.timeStamp - interaction.prevEvent.timeStamp;
+            this.duration  = this.timeStamp - interaction.downTimes[0];
+
+            if (event instanceof InteractEvent) {
+                var dx = this[sourceX] - interaction.prevEvent[sourceX],
+                    dy = this[sourceY] - interaction.prevEvent[sourceY],
+                    dt = this.dt / 1000;
+
+                this.speed = hypot(dx, dy) / dt;
+                this.velocityX = dx / dt;
+                this.velocityY = dy / dt;
+            }
+            // if normal move or end event, use previous user event coords
+            else {
+                // speed and velocity in pixels per second
+                this.speed = interaction.pointerDelta[deltaSource].speed;
+                this.velocityX = interaction.pointerDelta[deltaSource].vx;
+                this.velocityY = interaction.pointerDelta[deltaSource].vy;
+            }
+        }
+
+        if ((ending || phase === 'inertiastart')
+            && interaction.prevEvent.speed > 600 && this.timeStamp - interaction.prevEvent.timeStamp < 150) {
+
+            var angle = 180 * Math.atan2(interaction.prevEvent.velocityY, interaction.prevEvent.velocityX) / Math.PI,
+                overlap = 22.5;
+
+            if (angle < 0) {
+                angle += 360;
+            }
+
+            var left = 135 - overlap <= angle && angle < 225 + overlap,
+                up   = 225 - overlap <= angle && angle < 315 + overlap,
+
+                right = !left && (315 - overlap <= angle || angle <  45 + overlap),
+                down  = !up   &&   45 - overlap <= angle && angle < 135 + overlap;
+
+            this.swipe = {
+                up   : up,
+                down : down,
+                left : left,
+                right: right,
+                angle: angle,
+                speed: interaction.prevEvent.speed,
+                velocity: {
+                    x: interaction.prevEvent.velocityX,
+                    y: interaction.prevEvent.velocityY
+                }
+            };
+        }
+    }
+
+    InteractEvent.prototype = {
+        preventDefault: blank,
+        stopImmediatePropagation: function () {
+            this.immediatePropagationStopped = this.propagationStopped = true;
+        },
+        stopPropagation: function () {
+            this.propagationStopped = true;
+        }
+    };
+
+    function preventOriginalDefault () {
+        this.originalEvent.preventDefault();
+    }
+
+    function getActionCursor (action) {
+        var cursor = '';
+
+        if (action.name === 'drag') {
+            cursor =  actionCursors.drag;
+        }
+        if (action.name === 'resize') {
+            if (action.axis) {
+                cursor =  actionCursors[action.name + action.axis];
+            }
+            else if (action.edges) {
+                var cursorKey = 'resize',
+                    edgeNames = ['top', 'bottom', 'left', 'right'];
+
+                for (var i = 0; i < 4; i++) {
+                    if (action.edges[edgeNames[i]]) {
+                        cursorKey += edgeNames[i];
+                    }
+                }
+
+                cursor = actionCursors[cursorKey];
+            }
+        }
+
+        return cursor;
+    }
+
+    function checkResizeEdge (name, value, page, element, interactableElement, rect, margin) {
+        // false, '', undefined, null
+        if (!value) { return false; }
+
+        // true value, use pointer coords and element rect
+        if (value === true) {
+            // if dimensions are negative, "switch" edges
+            var width = isNumber(rect.width)? rect.width : rect.right - rect.left,
+                height = isNumber(rect.height)? rect.height : rect.bottom - rect.top;
+
+            if (width < 0) {
+                if      (name === 'left' ) { name = 'right'; }
+                else if (name === 'right') { name = 'left' ; }
+            }
+            if (height < 0) {
+                if      (name === 'top'   ) { name = 'bottom'; }
+                else if (name === 'bottom') { name = 'top'   ; }
+            }
+
+            if (name === 'left'  ) { return page.x < ((width  >= 0? rect.left: rect.right ) + margin); }
+            if (name === 'top'   ) { return page.y < ((height >= 0? rect.top : rect.bottom) + margin); }
+
+            if (name === 'right' ) { return page.x > ((width  >= 0? rect.right : rect.left) - margin); }
+            if (name === 'bottom') { return page.y > ((height >= 0? rect.bottom: rect.top ) - margin); }
+        }
+
+        // the remaining checks require an element
+        if (!isElement(element)) { return false; }
+
+        return isElement(value)
+                    // the value is an element to use as a resize handle
+                    ? value === element
+                    // otherwise check if element matches value as selector
+                    : matchesUpTo(element, value, interactableElement);
+    }
+
+    function defaultActionChecker (pointer, interaction, element) {
+        var rect = this.getRect(element),
+            shouldResize = false,
+            action = null,
+            resizeAxes = null,
+            resizeEdges,
+            page = extend({}, interaction.curCoords.page),
+            options = this.options;
+
+        if (!rect) { return null; }
+
+        if (actionIsEnabled.resize && options.resize.enabled) {
+            var resizeOptions = options.resize;
+
+            resizeEdges = {
+                left: false, right: false, top: false, bottom: false
+            };
+
+            // if using resize.edges
+            if (isObject(resizeOptions.edges)) {
+                for (var edge in resizeEdges) {
+                    resizeEdges[edge] = checkResizeEdge(edge,
+                                                        resizeOptions.edges[edge],
+                                                        page,
+                                                        interaction._eventTarget,
+                                                        element,
+                                                        rect,
+                                                        resizeOptions.margin || margin);
+                }
+
+                resizeEdges.left = resizeEdges.left && !resizeEdges.right;
+                resizeEdges.top  = resizeEdges.top  && !resizeEdges.bottom;
+
+                shouldResize = resizeEdges.left || resizeEdges.right || resizeEdges.top || resizeEdges.bottom;
+            }
+            else {
+                var right  = options.resize.axis !== 'y' && page.x > (rect.right  - margin),
+                    bottom = options.resize.axis !== 'x' && page.y > (rect.bottom - margin);
+
+                shouldResize = right || bottom;
+                resizeAxes = (right? 'x' : '') + (bottom? 'y' : '');
+            }
+        }
+
+        action = shouldResize
+            ? 'resize'
+            : actionIsEnabled.drag && options.drag.enabled
+                ? 'drag'
+                : null;
+
+        if (actionIsEnabled.gesture
+            && interaction.pointerIds.length >=2
+            && !(interaction.dragging || interaction.resizing)) {
+            action = 'gesture';
+        }
+
+        if (action) {
+            return {
+                name: action,
+                axis: resizeAxes,
+                edges: resizeEdges
+            };
+        }
+
+        return null;
+    }
+
+    // Check if action is enabled globally and the current target supports it
+    // If so, return the validated action. Otherwise, return null
+    function validateAction (action, interactable) {
+        if (!isObject(action)) { return null; }
+
+        var actionName = action.name,
+            options = interactable.options;
+
+        if ((  (actionName  === 'resize'   && options.resize.enabled )
+            || (actionName      === 'drag'     && options.drag.enabled  )
+            || (actionName      === 'gesture'  && options.gesture.enabled))
+            && actionIsEnabled[actionName]) {
+
+            if (actionName === 'resize' || actionName === 'resizeyx') {
+                actionName = 'resizexy';
+            }
+
+            return action;
+        }
+        return null;
+    }
+
+    var listeners = {},
+        interactionListeners = [
+            'dragStart', 'dragMove', 'resizeStart', 'resizeMove', 'gestureStart', 'gestureMove',
+            'pointerOver', 'pointerOut', 'pointerHover', 'selectorDown',
+            'pointerDown', 'pointerMove', 'pointerUp', 'pointerCancel', 'pointerEnd',
+            'addPointer', 'removePointer', 'recordPointer', 'autoScrollMove'
+        ];
+
+    for (var i = 0, len = interactionListeners.length; i < len; i++) {
+        var name = interactionListeners[i];
+
+        listeners[name] = doOnInteractions(name);
+    }
+
+    // bound to the interactable context when a DOM event
+    // listener is added to a selector interactable
+    function delegateListener (event, useCapture) {
+        var fakeEvent = {},
+            delegated = delegatedEvents[event.type],
+            eventTarget = getActualElement(event.path
+                                           ? event.path[0]
+                                           : event.target),
+            element = eventTarget;
+
+        useCapture = useCapture? true: false;
+
+        // duplicate the event so that currentTarget can be changed
+        for (var prop in event) {
+            fakeEvent[prop] = event[prop];
+        }
+
+        fakeEvent.originalEvent = event;
+        fakeEvent.preventDefault = preventOriginalDefault;
+
+        // climb up document tree looking for selector matches
+        while (isElement(element)) {
+            for (var i = 0; i < delegated.selectors.length; i++) {
+                var selector = delegated.selectors[i],
+                    context = delegated.contexts[i];
+
+                if (matchesSelector(element, selector)
+                    && nodeContains(context, eventTarget)
+                    && nodeContains(context, element)) {
+
+                    var listeners = delegated.listeners[i];
+
+                    fakeEvent.currentTarget = element;
+
+                    for (var j = 0; j < listeners.length; j++) {
+                        if (listeners[j][1] === useCapture) {
+                            listeners[j][0](fakeEvent);
+                        }
+                    }
+                }
+            }
+
+            element = parentElement(element);
+        }
+    }
+
+    function delegateUseCapture (event) {
+        return delegateListener.call(this, event, true);
+    }
+
+    interactables.indexOfElement = function indexOfElement (element, context) {
+        context = context || document;
+
+        for (var i = 0; i < this.length; i++) {
+            var interactable = this[i];
+
+            if ((interactable.selector === element
+                && (interactable._context === context))
+                || (!interactable.selector && interactable._element === element)) {
+
+                return i;
+            }
+        }
+        return -1;
+    };
+
+    interactables.get = function interactableGet (element, options) {
+        return this[this.indexOfElement(element, options && options.context)];
+    };
+
+    interactables.forEachSelector = function (callback) {
+        for (var i = 0; i < this.length; i++) {
+            var interactable = this[i];
+
+            if (!interactable.selector) {
+                continue;
+            }
+
+            var ret = callback(interactable, interactable.selector, interactable._context, i, this);
+
+            if (ret !== undefined) {
+                return ret;
+            }
+        }
+    };
+
+    /*\
+     * interact
+     [ method ]
+     *
+     * The methods of this variable can be used to set elements as
+     * interactables and also to change various default settings.
+     *
+     * Calling it as a function and passing an element or a valid CSS selector
+     * string returns an Interactable object which has various methods to
+     * configure it.
+     *
+     - element (Element | string) The HTML or SVG Element to interact with or CSS selector
+     = (object) An @Interactable
+     *
+     > Usage
+     | interact(document.getElementById('draggable')).draggable(true);
+     |
+     | var rectables = interact('rect');
+     | rectables
+     |     .gesturable(true)
+     |     .on('gesturemove', function (event) {
+     |         // something cool...
+     |     })
+     |     .autoScroll(true);
+    \*/
+    function interact (element, options) {
+        return interactables.get(element, options) || new Interactable(element, options);
+    }
+
+    /*\
+     * Interactable
+     [ property ]
+     **
+     * Object type returned by @interact
+    \*/
+    function Interactable (element, options) {
+        this._element = element;
+        this._iEvents = this._iEvents || {};
+
+        var _window;
+
+        if (trySelector(element)) {
+            this.selector = element;
+
+            var context = options && options.context;
+
+            _window = context? getWindow(context) : window;
+
+            if (context && (_window.Node
+                    ? context instanceof _window.Node
+                    : (isElement(context) || context === _window.document))) {
+
+                this._context = context;
+            }
+        }
+        else {
+            _window = getWindow(element);
+
+            if (isElement(element, _window)) {
+
+                if (PointerEvent) {
+                    events.add(this._element, pEventTypes.down, listeners.pointerDown );
+                    events.add(this._element, pEventTypes.move, listeners.pointerHover);
+                }
+                else {
+                    events.add(this._element, 'mousedown' , listeners.pointerDown );
+                    events.add(this._element, 'mousemove' , listeners.pointerHover);
+                    events.add(this._element, 'touchstart', listeners.pointerDown );
+                    events.add(this._element, 'touchmove' , listeners.pointerHover);
+                }
+            }
+        }
+
+        this._doc = _window.document;
+
+        if (!contains(documents, this._doc)) {
+            listenToDocument(this._doc);
+        }
+
+        interactables.push(this);
+
+        this.set(options);
+    }
+
+    Interactable.prototype = {
+        setOnEvents: function (action, phases) {
+            if (action === 'drop') {
+                if (isFunction(phases.ondrop)          ) { this.ondrop           = phases.ondrop          ; }
+                if (isFunction(phases.ondropactivate)  ) { this.ondropactivate   = phases.ondropactivate  ; }
+                if (isFunction(phases.ondropdeactivate)) { this.ondropdeactivate = phases.ondropdeactivate; }
+                if (isFunction(phases.ondragenter)     ) { this.ondragenter      = phases.ondragenter     ; }
+                if (isFunction(phases.ondragleave)     ) { this.ondragleave      = phases.ondragleave     ; }
+                if (isFunction(phases.ondropmove)      ) { this.ondropmove       = phases.ondropmove      ; }
+            }
+            else {
+                action = 'on' + action;
+
+                if (isFunction(phases.onstart)       ) { this[action + 'start'         ] = phases.onstart         ; }
+                if (isFunction(phases.onmove)        ) { this[action + 'move'          ] = phases.onmove          ; }
+                if (isFunction(phases.onend)         ) { this[action + 'end'           ] = phases.onend           ; }
+                if (isFunction(phases.oninertiastart)) { this[action + 'inertiastart'  ] = phases.oninertiastart  ; }
+            }
+
+            return this;
+        },
+
+        /*\
+         * Interactable.draggable
+         [ method ]
+         *
+         * Gets or sets whether drag actions can be performed on the
+         * Interactable
+         *
+         = (boolean) Indicates if this can be the target of drag events
+         | var isDraggable = interact('ul li').draggable();
+         * or
+         - options (boolean | object) #optional true/false or An object with event listeners to be fired on drag events (object makes the Interactable draggable)
+         = (object) This Interactable
+         | interact(element).draggable({
+         |     onstart: function (event) {},
+         |     onmove : function (event) {},
+         |     onend  : function (event) {},
+         |
+         |     // the axis in which the first movement must be
+         |     // for the drag sequence to start
+         |     // 'xy' by default - any direction
+         |     axis: 'x' || 'y' || 'xy',
+         |
+         |     // max number of drags that can happen concurrently
+         |     // with elements of this Interactable. Infinity by default
+         |     max: Infinity,
+         |
+         |     // max number of drags that can target the same element+Interactable
+         |     // 1 by default
+         |     maxPerElement: 2
+         | });
+        \*/
+        draggable: function (options) {
+            if (isObject(options)) {
+                this.options.drag.enabled = options.enabled === false? false: true;
+                this.setPerAction('drag', options);
+                this.setOnEvents('drag', options);
+
+                if (/^x$|^y$|^xy$/.test(options.axis)) {
+                    this.options.drag.axis = options.axis;
+                }
+                else if (options.axis === null) {
+                    delete this.options.drag.axis;
+                }
+
+                return this;
+            }
+
+            if (isBool(options)) {
+                this.options.drag.enabled = options;
+
+                return this;
+            }
+
+            return this.options.drag;
+        },
+
+        setPerAction: function (action, options) {
+            // for all the default per-action options
+            for (var option in options) {
+                // if this option exists for this action
+                if (option in defaultOptions[action]) {
+                    // if the option in the options arg is an object value
+                    if (isObject(options[option])) {
+                        // duplicate the object
+                        this.options[action][option] = extend(this.options[action][option] || {}, options[option]);
+
+                        if (isObject(defaultOptions.perAction[option]) && 'enabled' in defaultOptions.perAction[option]) {
+                            this.options[action][option].enabled = options[option].enabled === false? false : true;
+                        }
+                    }
+                    else if (isBool(options[option]) && isObject(defaultOptions.perAction[option])) {
+                        this.options[action][option].enabled = options[option];
+                    }
+                    else if (options[option] !== undefined) {
+                        // or if it's not undefined, do a plain assignment
+                        this.options[action][option] = options[option];
+                    }
+                }
+            }
+        },
+
+        /*\
+         * Interactable.dropzone
+         [ method ]
+         *
+         * Returns or sets whether elements can be dropped onto this
+         * Interactable to trigger drop events
+         *
+         * Dropzones can receive the following events:
+         *  - `dropactivate` and `dropdeactivate` when an acceptable drag starts and ends
+         *  - `dragenter` and `dragleave` when a draggable enters and leaves the dropzone
+         *  - `dragmove` when a draggable that has entered the dropzone is moved
+         *  - `drop` when a draggable is dropped into this dropzone
+         *
+         *  Use the `accept` option to allow only elements that match the given CSS selector or element.
+         *
+         *  Use the `overlap` option to set how drops are checked for. The allowed values are:
+         *   - `'pointer'`, the pointer must be over the dropzone (default)
+         *   - `'center'`, the draggable element's center must be over the dropzone
+         *   - a number from 0-1 which is the `(intersection area) / (draggable area)`.
+         *       e.g. `0.5` for drop to happen when half of the area of the
+         *       draggable is over the dropzone
+         *
+         - options (boolean | object | null) #optional The new value to be set.
+         | interact('.drop').dropzone({
+         |   accept: '.can-drop' || document.getElementById('single-drop'),
+         |   overlap: 'pointer' || 'center' || zeroToOne
+         | }
+         = (boolean | object) The current setting or this Interactable
+        \*/
+        dropzone: function (options) {
+            if (isObject(options)) {
+                this.options.drop.enabled = options.enabled === false? false: true;
+                this.setOnEvents('drop', options);
+
+                if (/^(pointer|center)$/.test(options.overlap)) {
+                    this.options.drop.overlap = options.overlap;
+                }
+                else if (isNumber(options.overlap)) {
+                    this.options.drop.overlap = Math.max(Math.min(1, options.overlap), 0);
+                }
+                if ('accept' in options) {
+                  this.options.drop.accept = options.accept;
+                }
+                if ('checker' in options) {
+                  this.options.drop.checker = options.checker;
+                }
+
+                return this;
+            }
+
+            if (isBool(options)) {
+                this.options.drop.enabled = options;
+
+                return this;
+            }
+
+            return this.options.drop;
+        },
+
+        dropCheck: function (dragEvent, event, draggable, draggableElement, dropElement, rect) {
+            var dropped = false;
+
+            // if the dropzone has no rect (eg. display: none)
+            // call the custom dropChecker or just return false
+            if (!(rect = rect || this.getRect(dropElement))) {
+                return (this.options.drop.checker
+                    ? this.options.drop.checker(dragEvent, event, dropped, this, dropElement, draggable, draggableElement)
+                    : false);
+            }
+
+            var dropOverlap = this.options.drop.overlap;
+
+            if (dropOverlap === 'pointer') {
+                var page = getPageXY(dragEvent),
+                    origin = getOriginXY(draggable, draggableElement),
+                    horizontal,
+                    vertical;
+
+                page.x += origin.x;
+                page.y += origin.y;
+
+                horizontal = (page.x > rect.left) && (page.x < rect.right);
+                vertical   = (page.y > rect.top ) && (page.y < rect.bottom);
+
+                dropped = horizontal && vertical;
+            }
+
+            var dragRect = draggable.getRect(draggableElement);
+
+            if (dropOverlap === 'center') {
+                var cx = dragRect.left + dragRect.width  / 2,
+                    cy = dragRect.top  + dragRect.height / 2;
+
+                dropped = cx >= rect.left && cx <= rect.right && cy >= rect.top && cy <= rect.bottom;
+            }
+
+            if (isNumber(dropOverlap)) {
+                var overlapArea  = (Math.max(0, Math.min(rect.right , dragRect.right ) - Math.max(rect.left, dragRect.left))
+                                  * Math.max(0, Math.min(rect.bottom, dragRect.bottom) - Math.max(rect.top , dragRect.top ))),
+                    overlapRatio = overlapArea / (dragRect.width * dragRect.height);
+
+                dropped = overlapRatio >= dropOverlap;
+            }
+
+            if (this.options.drop.checker) {
+                dropped = this.options.drop.checker(dragEvent, event, dropped, this, dropElement, draggable, draggableElement);
+            }
+
+            return dropped;
+        },
+
+        /*\
+         * Interactable.dropChecker
+         [ method ]
+         *
+         * DEPRECATED. Use interactable.dropzone({ checker: function... }) instead.
+         *
+         * Gets or sets the function used to check if a dragged element is
+         * over this Interactable.
+         *
+         - checker (function) #optional The function that will be called when checking for a drop
+         = (Function | Interactable) The checker function or this Interactable
+         *
+         * The checker function takes the following arguments:
+         *
+         - dragEvent (InteractEvent) The related dragmove or dragend event
+         - event (TouchEvent | PointerEvent | MouseEvent) The user move/up/end Event related to the dragEvent
+         - dropped (boolean) The value from the default drop checker
+         - dropzone (Interactable) The dropzone interactable
+         - dropElement (Element) The dropzone element
+         - draggable (Interactable) The Interactable being dragged
+         - draggableElement (Element) The actual element that's being dragged
+         *
+         > Usage:
+         | interact(target)
+         | .dropChecker(function(dragEvent,         // related dragmove or dragend event
+         |                       event,             // TouchEvent/PointerEvent/MouseEvent
+         |                       dropped,           // bool result of the default checker
+         |                       dropzone,          // dropzone Interactable
+         |                       dropElement,       // dropzone elemnt
+         |                       draggable,         // draggable Interactable
+         |                       draggableElement) {// draggable element
+         |
+         |   return dropped && event.target.hasAttribute('allow-drop');
+         | }
+        \*/
+        dropChecker: function (checker) {
+            if (isFunction(checker)) {
+                this.options.drop.checker = checker;
+
+                return this;
+            }
+            if (checker === null) {
+                delete this.options.getRect;
+
+                return this;
+            }
+
+            return this.options.drop.checker;
+        },
+
+        /*\
+         * Interactable.accept
+         [ method ]
+         *
+         * Deprecated. add an `accept` property to the options object passed to
+         * @Interactable.dropzone instead.
+         *
+         * Gets or sets the Element or CSS selector match that this
+         * Interactable accepts if it is a dropzone.
+         *
+         - newValue (Element | string | null) #optional
+         * If it is an Element, then only that element can be dropped into this dropzone.
+         * If it is a string, the element being dragged must match it as a selector.
+         * If it is null, the accept options is cleared - it accepts any element.
+         *
+         = (string | Element | null | Interactable) The current accept option if given `undefined` or this Interactable
+        \*/
+        accept: function (newValue) {
+            if (isElement(newValue)) {
+                this.options.drop.accept = newValue;
+
+                return this;
+            }
+
+            // test if it is a valid CSS selector
+            if (trySelector(newValue)) {
+                this.options.drop.accept = newValue;
+
+                return this;
+            }
+
+            if (newValue === null) {
+                delete this.options.drop.accept;
+
+                return this;
+            }
+
+            return this.options.drop.accept;
+        },
+
+        /*\
+         * Interactable.resizable
+         [ method ]
+         *
+         * Gets or sets whether resize actions can be performed on the
+         * Interactable
+         *
+         = (boolean) Indicates if this can be the target of resize elements
+         | var isResizeable = interact('input[type=text]').resizable();
+         * or
+         - options (boolean | object) #optional true/false or An object with event listeners to be fired on resize events (object makes the Interactable resizable)
+         = (object) This Interactable
+         | interact(element).resizable({
+         |     onstart: function (event) {},
+         |     onmove : function (event) {},
+         |     onend  : function (event) {},
+         |
+         |     edges: {
+         |       top   : true,       // Use pointer coords to check for resize.
+         |       left  : false,      // Disable resizing from left edge.
+         |       bottom: '.resize-s',// Resize if pointer target matches selector
+         |       right : handleEl    // Resize if pointer target is the given Element
+         |     },
+         |
+         |     // Width and height can be adjusted independently. When `true`, width and
+         |     // height are adjusted at a 1:1 ratio.
+         |     square: false,
+         |
+         |     // Width and height can be adjusted independently. When `true`, width and
+         |     // height maintain the aspect ratio they had when resizing started.
+         |     preserveAspectRatio: false,
+         |
+         |     // a value of 'none' will limit the resize rect to a minimum of 0x0
+         |     // 'negate' will allow the rect to have negative width/height
+         |     // 'reposition' will keep the width/height positive by swapping
+         |     // the top and bottom edges and/or swapping the left and right edges
+         |     invert: 'none' || 'negate' || 'reposition'
+         |
+         |     // limit multiple resizes.
+         |     // See the explanation in the @Interactable.draggable example
+         |     max: Infinity,
+         |     maxPerElement: 1,
+         | });
+        \*/
+        resizable: function (options) {
+            if (isObject(options)) {
+                this.options.resize.enabled = options.enabled === false? false: true;
+                this.setPerAction('resize', options);
+                this.setOnEvents('resize', options);
+
+                if (/^x$|^y$|^xy$/.test(options.axis)) {
+                    this.options.resize.axis = options.axis;
+                }
+                else if (options.axis === null) {
+                    this.options.resize.axis = defaultOptions.resize.axis;
+                }
+
+                if (isBool(options.preserveAspectRatio)) {
+                    this.options.resize.preserveAspectRatio = options.preserveAspectRatio;
+                }
+                else if (isBool(options.square)) {
+                    this.options.resize.square = options.square;
+                }
+
+                return this;
+            }
+            if (isBool(options)) {
+                this.options.resize.enabled = options;
+
+                return this;
+            }
+            return this.options.resize;
+        },
+
+        /*\
+         * Interactable.squareResize
+         [ method ]
+         *
+         * Deprecated. Add a `square: true || false` property to @Interactable.resizable instead
+         *
+         * Gets or sets whether resizing is forced 1:1 aspect
+         *
+         = (boolean) Current setting
+         *
+         * or
+         *
+         - newValue (boolean) #optional
+         = (object) this Interactable
+        \*/
+        squareResize: function (newValue) {
+            if (isBool(newValue)) {
+                this.options.resize.square = newValue;
+
+                return this;
+            }
+
+            if (newValue === null) {
+                delete this.options.resize.square;
+
+                return this;
+            }
+
+            return this.options.resize.square;
+        },
+
+        /*\
+         * Interactable.gesturable
+         [ method ]
+         *
+         * Gets or sets whether multitouch gestures can be performed on the
+         * Interactable's element
+         *
+         = (boolean) Indicates if this can be the target of gesture events
+         | var isGestureable = interact(element).gesturable();
+         * or
+         - options (boolean | object) #optional true/false or An object with event listeners to be fired on gesture events (makes the Interactable gesturable)
+         = (object) this Interactable
+         | interact(element).gesturable({
+         |     onstart: function (event) {},
+         |     onmove : function (event) {},
+         |     onend  : function (event) {},
+         |
+         |     // limit multiple gestures.
+         |     // See the explanation in @Interactable.draggable example
+         |     max: Infinity,
+         |     maxPerElement: 1,
+         | });
+        \*/
+        gesturable: function (options) {
+            if (isObject(options)) {
+                this.options.gesture.enabled = options.enabled === false? false: true;
+                this.setPerAction('gesture', options);
+                this.setOnEvents('gesture', options);
+
+                return this;
+            }
+
+            if (isBool(options)) {
+                this.options.gesture.enabled = options;
+
+                return this;
+            }
+
+            return this.options.gesture;
+        },
+
+        /*\
+         * Interactable.autoScroll
+         [ method ]
+         **
+         * Deprecated. Add an `autoscroll` property to the options object
+         * passed to @Interactable.draggable or @Interactable.resizable instead.
+         *
+         * Returns or sets whether dragging and resizing near the edges of the
+         * window/container trigger autoScroll for this Interactable
+         *
+         = (object) Object with autoScroll properties
+         *
+         * or
+         *
+         - options (object | boolean) #optional
+         * options can be:
+         * - an object with margin, distance and interval properties,
+         * - true or false to enable or disable autoScroll or
+         = (Interactable) this Interactable
+        \*/
+        autoScroll: function (options) {
+            if (isObject(options)) {
+                options = extend({ actions: ['drag', 'resize']}, options);
+            }
+            else if (isBool(options)) {
+                options = { actions: ['drag', 'resize'], enabled: options };
+            }
+
+            return this.setOptions('autoScroll', options);
+        },
+
+        /*\
+         * Interactable.snap
+         [ method ]
+         **
+         * Deprecated. Add a `snap` property to the options object passed
+         * to @Interactable.draggable or @Interactable.resizable instead.
+         *
+         * Returns or sets if and how action coordinates are snapped. By
+         * default, snapping is relative to the pointer coordinates. You can
+         * change this by setting the
+         * [`elementOrigin`](https://github.com/taye/interact.js/pull/72).
+         **
+         = (boolean | object) `false` if snap is disabled; object with snap properties if snap is enabled
+         **
+         * or
+         **
+         - options (object | boolean | null) #optional
+         = (Interactable) this Interactable
+         > Usage
+         | interact(document.querySelector('#thing')).snap({
+         |     targets: [
+         |         // snap to this specific point
+         |         {
+         |             x: 100,
+         |             y: 100,
+         |             range: 25
+         |         },
+         |         // give this function the x and y page coords and snap to the object returned
+         |         function (x, y) {
+         |             return {
+         |                 x: x,
+         |                 y: (75 + 50 * Math.sin(x * 0.04)),
+         |                 range: 40
+         |             };
+         |         },
+         |         // create a function that snaps to a grid
+         |         interact.createSnapGrid({
+         |             x: 50,
+         |             y: 50,
+         |             range: 10,              // optional
+         |             offset: { x: 5, y: 10 } // optional
+         |         })
+         |     ],
+         |     // do not snap during normal movement.
+         |     // Instead, trigger only one snapped move event
+         |     // immediately before the end event.
+         |     endOnly: true,
+         |
+         |     relativePoints: [
+         |         { x: 0, y: 0 },  // snap relative to the top left of the element
+         |         { x: 1, y: 1 },  // and also to the bottom right
+         |     ],  
+         |
+         |     // offset the snap target coordinates
+         |     // can be an object with x/y or 'startCoords'
+         |     offset: { x: 50, y: 50 }
+         |   }
+         | });
+        \*/
+        snap: function (options) {
+            var ret = this.setOptions('snap', options);
+
+            if (ret === this) { return this; }
+
+            return ret.drag;
+        },
+
+        setOptions: function (option, options) {
+            var actions = options && isArray(options.actions)
+                    ? options.actions
+                    : ['drag'];
+
+            var i;
+
+            if (isObject(options) || isBool(options)) {
+                for (i = 0; i < actions.length; i++) {
+                    var action = /resize/.test(actions[i])? 'resize' : actions[i];
+
+                    if (!isObject(this.options[action])) { continue; }
+
+                    var thisOption = this.options[action][option];
+
+                    if (isObject(options)) {
+                        extend(thisOption, options);
+                        thisOption.enabled = options.enabled === false? false: true;
+
+                        if (option === 'snap') {
+                            if (thisOption.mode === 'grid') {
+                                thisOption.targets = [
+                                    interact.createSnapGrid(extend({
+                                        offset: thisOption.gridOffset || { x: 0, y: 0 }
+                                    }, thisOption.grid || {}))
+                                ];
+                            }
+                            else if (thisOption.mode === 'anchor') {
+                                thisOption.targets = thisOption.anchors;
+                            }
+                            else if (thisOption.mode === 'path') {
+                                thisOption.targets = thisOption.paths;
+                            }
+
+                            if ('elementOrigin' in options) {
+                                thisOption.relativePoints = [options.elementOrigin];
+                            }
+                        }
+                    }
+                    else if (isBool(options)) {
+                        thisOption.enabled = options;
+                    }
+                }
+
+                return this;
+            }
+
+            var ret = {},
+                allActions = ['drag', 'resize', 'gesture'];
+
+            for (i = 0; i < allActions.length; i++) {
+                if (option in defaultOptions[allActions[i]]) {
+                    ret[allActions[i]] = this.options[allActions[i]][option];
+                }
+            }
+
+            return ret;
+        },
+
+
+        /*\
+         * Interactable.inertia
+         [ method ]
+         **
+         * Deprecated. Add an `inertia` property to the options object passed
+         * to @Interactable.draggable or @Interactable.resizable instead.
+         *
+         * Returns or sets if and how events continue to run after the pointer is released
+         **
+         = (boolean | object) `false` if inertia is disabled; `object` with inertia properties if inertia is enabled
+         **
+         * or
+         **
+         - options (object | boolean | null) #optional
+         = (Interactable) this Interactable
+         > Usage
+         | // enable and use default settings
+         | interact(element).inertia(true);
+         |
+         | // enable and use custom settings
+         | interact(element).inertia({
+         |     // value greater than 0
+         |     // high values slow the object down more quickly
+         |     resistance     : 16,
+         |
+         |     // the minimum launch speed (pixels per second) that results in inertia start
+         |     minSpeed       : 200,
+         |
+         |     // inertia will stop when the object slows down to this speed
+         |     endSpeed       : 20,
+         |
+         |     // boolean; should actions be resumed when the pointer goes down during inertia
+         |     allowResume    : true,
+         |
+         |     // boolean; should the jump when resuming from inertia be ignored in event.dx/dy
+         |     zeroResumeDelta: false,
+         |
+         |     // if snap/restrict are set to be endOnly and inertia is enabled, releasing
+         |     // the pointer without triggering inertia will animate from the release
+         |     // point to the snaped/restricted point in the given amount of time (ms)
+         |     smoothEndDuration: 300,
+         |
+         |     // an array of action types that can have inertia (no gesture)
+         |     actions        : ['drag', 'resize']
+         | });
+         |
+         | // reset custom settings and use all defaults
+         | interact(element).inertia(null);
+        \*/
+        inertia: function (options) {
+            var ret = this.setOptions('inertia', options);
+
+            if (ret === this) { return this; }
+
+            return ret.drag;
+        },
+
+        getAction: function (pointer, event, interaction, element) {
+            var action = this.defaultActionChecker(pointer, interaction, element);
+
+            if (this.options.actionChecker) {
+                return this.options.actionChecker(pointer, event, action, this, element, interaction);
+            }
+
+            return action;
+        },
+
+        defaultActionChecker: defaultActionChecker,
+
+        /*\
+         * Interactable.actionChecker
+         [ method ]
+         *
+         * Gets or sets the function used to check action to be performed on
+         * pointerDown
+         *
+         - checker (function | null) #optional A function which takes a pointer event, defaultAction string, interactable, element and interaction as parameters and returns an object with name property 'drag' 'resize' or 'gesture' and optionally an `edges` object with boolean 'top', 'left', 'bottom' and right props.
+         = (Function | Interactable) The checker function or this Interactable
+         *
+         | interact('.resize-drag')
+         |   .resizable(true)
+         |   .draggable(true)
+         |   .actionChecker(function (pointer, event, action, interactable, element, interaction) {
+         |
+         |   if (interact.matchesSelector(event.target, '.drag-handle') {
+         |     // force drag with handle target
+         |     action.name = drag;
+         |   }
+         |   else {
+         |     // resize from the top and right edges
+         |     action.name  = 'resize';
+         |     action.edges = { top: true, right: true };
+         |   }
+         |
+         |   return action;
+         | });
+        \*/
+        actionChecker: function (checker) {
+            if (isFunction(checker)) {
+                this.options.actionChecker = checker;
+
+                return this;
+            }
+
+            if (checker === null) {
+                delete this.options.actionChecker;
+
+                return this;
+            }
+
+            return this.options.actionChecker;
+        },
+
+        /*\
+         * Interactable.getRect
+         [ method ]
+         *
+         * The default function to get an Interactables bounding rect. Can be
+         * overridden using @Interactable.rectChecker.
+         *
+         - element (Element) #optional The element to measure.
+         = (object) The object's bounding rectangle.
+         o {
+         o     top   : 0,
+         o     left  : 0,
+         o     bottom: 0,
+         o     right : 0,
+         o     width : 0,
+         o     height: 0
+         o }
+        \*/
+        getRect: function rectCheck (element) {
+            element = element || this._element;
+
+            if (this.selector && !(isElement(element))) {
+                element = this._context.querySelector(this.selector);
+            }
+
+            return getElementRect(element);
+        },
+
+        /*\
+         * Interactable.rectChecker
+         [ method ]
+         *
+         * Returns or sets the function used to calculate the interactable's
+         * element's rectangle
+         *
+         - checker (function) #optional A function which returns this Interactable's bounding rectangle. See @Interactable.getRect
+         = (function | object) The checker function or this Interactable
+        \*/
+        rectChecker: function (checker) {
+            if (isFunction(checker)) {
+                this.getRect = checker;
+
+                return this;
+            }
+
+            if (checker === null) {
+                delete this.options.getRect;
+
+                return this;
+            }
+
+            return this.getRect;
+        },
+
+        /*\
+         * Interactable.styleCursor
+         [ method ]
+         *
+         * Returns or sets whether the action that would be performed when the
+         * mouse on the element are checked on `mousemove` so that the cursor
+         * may be styled appropriately
+         *
+         - newValue (boolean) #optional
+         = (boolean | Interactable) The current setting or this Interactable
+        \*/
+        styleCursor: function (newValue) {
+            if (isBool(newValue)) {
+                this.options.styleCursor = newValue;
+
+                return this;
+            }
+
+            if (newValue === null) {
+                delete this.options.styleCursor;
+
+                return this;
+            }
+
+            return this.options.styleCursor;
+        },
+
+        /*\
+         * Interactable.preventDefault
+         [ method ]
+         *
+         * Returns or sets whether to prevent the browser's default behaviour
+         * in response to pointer events. Can be set to:
+         *  - `'always'` to always prevent
+         *  - `'never'` to never prevent
+         *  - `'auto'` to let interact.js try to determine what would be best
+         *
+         - newValue (string) #optional `true`, `false` or `'auto'`
+         = (string | Interactable) The current setting or this Interactable
+        \*/
+        preventDefault: function (newValue) {
+            if (/^(always|never|auto)$/.test(newValue)) {
+                this.options.preventDefault = newValue;
+                return this;
+            }
+
+            if (isBool(newValue)) {
+                this.options.preventDefault = newValue? 'always' : 'never';
+                return this;
+            }
+
+            return this.options.preventDefault;
+        },
+
+        /*\
+         * Interactable.origin
+         [ method ]
+         *
+         * Gets or sets the origin of the Interactable's element.  The x and y
+         * of the origin will be subtracted from action event coordinates.
+         *
+         - origin (object | string) #optional An object eg. { x: 0, y: 0 } or string 'parent', 'self' or any CSS selector
+         * OR
+         - origin (Element) #optional An HTML or SVG Element whose rect will be used
+         **
+         = (object) The current origin or this Interactable
+        \*/
+        origin: function (newValue) {
+            if (trySelector(newValue)) {
+                this.options.origin = newValue;
+                return this;
+            }
+            else if (isObject(newValue)) {
+                this.options.origin = newValue;
+                return this;
+            }
+
+            return this.options.origin;
+        },
+
+        /*\
+         * Interactable.deltaSource
+         [ method ]
+         *
+         * Returns or sets the mouse coordinate types used to calculate the
+         * movement of the pointer.
+         *
+         - newValue (string) #optional Use 'client' if you will be scrolling while interacting; Use 'page' if you want autoScroll to work
+         = (string | object) The current deltaSource or this Interactable
+        \*/
+        deltaSource: function (newValue) {
+            if (newValue === 'page' || newValue === 'client') {
+                this.options.deltaSource = newValue;
+
+                return this;
+            }
+
+            return this.options.deltaSource;
+        },
+
+        /*\
+         * Interactable.restrict
+         [ method ]
+         **
+         * Deprecated. Add a `restrict` property to the options object passed to
+         * @Interactable.draggable, @Interactable.resizable or @Interactable.gesturable instead.
+         *
+         * Returns or sets the rectangles within which actions on this
+         * interactable (after snap calculations) are restricted. By default,
+         * restricting is relative to the pointer coordinates. You can change
+         * this by setting the
+         * [`elementRect`](https://github.com/taye/interact.js/pull/72).
+         **
+         - options (object) #optional an object with keys drag, resize, and/or gesture whose values are rects, Elements, CSS selectors, or 'parent' or 'self'
+         = (object) The current restrictions object or this Interactable
+         **
+         | interact(element).restrict({
+         |     // the rect will be `interact.getElementRect(element.parentNode)`
+         |     drag: element.parentNode,
+         |
+         |     // x and y are relative to the the interactable's origin
+         |     resize: { x: 100, y: 100, width: 200, height: 200 }
+         | })
+         |
+         | interact('.draggable').restrict({
+         |     // the rect will be the selected element's parent
+         |     drag: 'parent',
+         |
+         |     // do not restrict during normal movement.
+         |     // Instead, trigger only one restricted move event
+         |     // immediately before the end event.
+         |     endOnly: true,
+         |
+         |     // https://github.com/taye/interact.js/pull/72#issue-41813493
+         |     elementRect: { top: 0, left: 0, bottom: 1, right: 1 }
+         | });
+        \*/
+        restrict: function (options) {
+            if (!isObject(options)) {
+                return this.setOptions('restrict', options);
+            }
+
+            var actions = ['drag', 'resize', 'gesture'],
+                ret;
+
+            for (var i = 0; i < actions.length; i++) {
+                var action = actions[i];
+
+                if (action in options) {
+                    var perAction = extend({
+                            actions: [action],
+                            restriction: options[action]
+                        }, options);
+
+                    ret = this.setOptions('restrict', perAction);
+                }
+            }
+
+            return ret;
+        },
+
+        /*\
+         * Interactable.context
+         [ method ]
+         *
+         * Gets the selector context Node of the Interactable. The default is `window.document`.
+         *
+         = (Node) The context Node of this Interactable
+         **
+        \*/
+        context: function () {
+            return this._context;
+        },
+
+        _context: document,
+
+        /*\
+         * Interactable.ignoreFrom
+         [ method ]
+         *
+         * If the target of the `mousedown`, `pointerdown` or `touchstart`
+         * event or any of it's parents match the given CSS selector or
+         * Element, no drag/resize/gesture is started.
+         *
+         - newValue (string | Element | null) #optional a CSS selector string, an Element or `null` to not ignore any elements
+         = (string | Element | object) The current ignoreFrom value or this Interactable
+         **
+         | interact(element, { ignoreFrom: document.getElementById('no-action') });
+         | // or
+         | interact(element).ignoreFrom('input, textarea, a');
+        \*/
+        ignoreFrom: function (newValue) {
+            if (trySelector(newValue)) {            // CSS selector to match event.target
+                this.options.ignoreFrom = newValue;
+                return this;
+            }
+
+            if (isElement(newValue)) {              // specific element
+                this.options.ignoreFrom = newValue;
+                return this;
+            }
+
+            return this.options.ignoreFrom;
+        },
+
+        /*\
+         * Interactable.allowFrom
+         [ method ]
+         *
+         * A drag/resize/gesture is started only If the target of the
+         * `mousedown`, `pointerdown` or `touchstart` event or any of it's
+         * parents match the given CSS selector or Element.
+         *
+         - newValue (string | Element | null) #optional a CSS selector string, an Element or `null` to allow from any element
+         = (string | Element | object) The current allowFrom value or this Interactable
+         **
+         | interact(element, { allowFrom: document.getElementById('drag-handle') });
+         | // or
+         | interact(element).allowFrom('.handle');
+        \*/
+        allowFrom: function (newValue) {
+            if (trySelector(newValue)) {            // CSS selector to match event.target
+                this.options.allowFrom = newValue;
+                return this;
+            }
+
+            if (isElement(newValue)) {              // specific element
+                this.options.allowFrom = newValue;
+                return this;
+            }
+
+            return this.options.allowFrom;
+        },
+
+        /*\
+         * Interactable.element
+         [ method ]
+         *
+         * If this is not a selector Interactable, it returns the element this
+         * interactable represents
+         *
+         = (Element) HTML / SVG Element
+        \*/
+        element: function () {
+            return this._element;
+        },
+
+        /*\
+         * Interactable.fire
+         [ method ]
+         *
+         * Calls listeners for the given InteractEvent type bound globally
+         * and directly to this Interactable
+         *
+         - iEvent (InteractEvent) The InteractEvent object to be fired on this Interactable
+         = (Interactable) this Interactable
+        \*/
+        fire: function (iEvent) {
+            if (!(iEvent && iEvent.type) || !contains(eventTypes, iEvent.type)) {
+                return this;
+            }
+
+            var listeners,
+                i,
+                len,
+                onEvent = 'on' + iEvent.type,
+                funcName = '';
+
+            // Interactable#on() listeners
+            if (iEvent.type in this._iEvents) {
+                listeners = this._iEvents[iEvent.type];
+
+                for (i = 0, len = listeners.length; i < len && !iEvent.immediatePropagationStopped; i++) {
+                    funcName = listeners[i].name;
+                    listeners[i](iEvent);
+                }
+            }
+
+            // interactable.onevent listener
+            if (isFunction(this[onEvent])) {
+                funcName = this[onEvent].name;
+                this[onEvent](iEvent);
+            }
+
+            // interact.on() listeners
+            if (iEvent.type in globalEvents && (listeners = globalEvents[iEvent.type]))  {
+
+                for (i = 0, len = listeners.length; i < len && !iEvent.immediatePropagationStopped; i++) {
+                    funcName = listeners[i].name;
+                    listeners[i](iEvent);
+                }
+            }
+
+            return this;
+        },
+
+        /*\
+         * Interactable.on
+         [ method ]
+         *
+         * Binds a listener for an InteractEvent or DOM event.
+         *
+         - eventType  (string | array | object) The types of events to listen for
+         - listener   (function) The function to be called on the given event(s)
+         - useCapture (boolean) #optional useCapture flag for addEventListener
+         = (object) This Interactable
+        \*/
+        on: function (eventType, listener, useCapture) {
+            var i;
+
+            if (isString(eventType) && eventType.search(' ') !== -1) {
+                eventType = eventType.trim().split(/ +/);
+            }
+
+            if (isArray(eventType)) {
+                for (i = 0; i < eventType.length; i++) {
+                    this.on(eventType[i], listener, useCapture);
+                }
+
+                return this;
+            }
+
+            if (isObject(eventType)) {
+                for (var prop in eventType) {
+                    this.on(prop, eventType[prop], listener);
+                }
+
+                return this;
+            }
+
+            if (eventType === 'wheel') {
+                eventType = wheelEvent;
+            }
+
+            // convert to boolean
+            useCapture = useCapture? true: false;
+
+            if (contains(eventTypes, eventType)) {
+                // if this type of event was never bound to this Interactable
+                if (!(eventType in this._iEvents)) {
+                    this._iEvents[eventType] = [listener];
+                }
+                else {
+                    this._iEvents[eventType].push(listener);
+                }
+            }
+            // delegated event for selector
+            else if (this.selector) {
+                if (!delegatedEvents[eventType]) {
+                    delegatedEvents[eventType] = {
+                        selectors: [],
+                        contexts : [],
+                        listeners: []
+                    };
+
+                    // add delegate listener functions
+                    for (i = 0; i < documents.length; i++) {
+                        events.add(documents[i], eventType, delegateListener);
+                        events.add(documents[i], eventType, delegateUseCapture, true);
+                    }
+                }
+
+                var delegated = delegatedEvents[eventType],
+                    index;
+
+                for (index = delegated.selectors.length - 1; index >= 0; index--) {
+                    if (delegated.selectors[index] === this.selector
+                        && delegated.contexts[index] === this._context) {
+                        break;
+                    }
+                }
+
+                if (index === -1) {
+                    index = delegated.selectors.length;
+
+                    delegated.selectors.push(this.selector);
+                    delegated.contexts .push(this._context);
+                    delegated.listeners.push([]);
+                }
+
+                // keep listener and useCapture flag
+                delegated.listeners[index].push([listener, useCapture]);
+            }
+            else {
+                events.add(this._element, eventType, listener, useCapture);
+            }
+
+            return this;
+        },
+
+        /*\
+         * Interactable.off
+         [ method ]
+         *
+         * Removes an InteractEvent or DOM event listener
+         *
+         - eventType  (string | array | object) The types of events that were listened for
+         - listener   (function) The listener function to be removed
+         - useCapture (boolean) #optional useCapture flag for removeEventListener
+         = (object) This Interactable
+        \*/
+        off: function (eventType, listener, useCapture) {
+            var i;
+
+            if (isString(eventType) && eventType.search(' ') !== -1) {
+                eventType = eventType.trim().split(/ +/);
+            }
+
+            if (isArray(eventType)) {
+                for (i = 0; i < eventType.length; i++) {
+                    this.off(eventType[i], listener, useCapture);
+                }
+
+                return this;
+            }
+
+            if (isObject(eventType)) {
+                for (var prop in eventType) {
+                    this.off(prop, eventType[prop], listener);
+                }
+
+                return this;
+            }
+
+            var eventList,
+                index = -1;
+
+            // convert to boolean
+            useCapture = useCapture? true: false;
+
+            if (eventType === 'wheel') {
+                eventType = wheelEvent;
+            }
+
+            // if it is an action event type
+            if (contains(eventTypes, eventType)) {
+                eventList = this._iEvents[eventType];
+
+                if (eventList && (index = indexOf(eventList, listener)) !== -1) {
+                    this._iEvents[eventType].splice(index, 1);
+                }
+            }
+            // delegated event
+            else if (this.selector) {
+                var delegated = delegatedEvents[eventType],
+                    matchFound = false;
+
+                if (!delegated) { return this; }
+
+                // count from last index of delegated to 0
+                for (index = delegated.selectors.length - 1; index >= 0; index--) {
+                    // look for matching selector and context Node
+                    if (delegated.selectors[index] === this.selector
+                        && delegated.contexts[index] === this._context) {
+
+                        var listeners = delegated.listeners[index];
+
+                        // each item of the listeners array is an array: [function, useCaptureFlag]
+                        for (i = listeners.length - 1; i >= 0; i--) {
+                            var fn = listeners[i][0],
+                                useCap = listeners[i][1];
+
+                            // check if the listener functions and useCapture flags match
+                            if (fn === listener && useCap === useCapture) {
+                                // remove the listener from the array of listeners
+                                listeners.splice(i, 1);
+
+                                // if all listeners for this interactable have been removed
+                                // remove the interactable from the delegated arrays
+                                if (!listeners.length) {
+                                    delegated.selectors.splice(index, 1);
+                                    delegated.contexts .splice(index, 1);
+                                    delegated.listeners.splice(index, 1);
+
+                                    // remove delegate function from context
+                                    events.remove(this._context, eventType, delegateListener);
+                                    events.remove(this._context, eventType, delegateUseCapture, true);
+
+                                    // remove the arrays if they are empty
+                                    if (!delegated.selectors.length) {
+                                        delegatedEvents[eventType] = null;
+                                    }
+                                }
+
+                                // only remove one listener
+                                matchFound = true;
+                                break;
+                            }
+                        }
+
+                        if (matchFound) { break; }
+                    }
+                }
+            }
+            // remove listener from this Interatable's element
+            else {
+                events.remove(this._element, eventType, listener, useCapture);
+            }
+
+            return this;
+        },
+
+        /*\
+         * Interactable.set
+         [ method ]
+         *
+         * Reset the options of this Interactable
+         - options (object) The new settings to apply
+         = (object) This Interactable
+        \*/
+        set: function (options) {
+            if (!isObject(options)) {
+                options = {};
+            }
+
+            this.options = extend({}, defaultOptions.base);
+
+            var i,
+                actions = ['drag', 'drop', 'resize', 'gesture'],
+                methods = ['draggable', 'dropzone', 'resizable', 'gesturable'],
+                perActions = extend(extend({}, defaultOptions.perAction), options[action] || {});
+
+            for (i = 0; i < actions.length; i++) {
+                var action = actions[i];
+
+                this.options[action] = extend({}, defaultOptions[action]);
+
+                this.setPerAction(action, perActions);
+
+                this[methods[i]](options[action]);
+            }
+
+            var settings = [
+                    'accept', 'actionChecker', 'allowFrom', 'deltaSource',
+                    'dropChecker', 'ignoreFrom', 'origin', 'preventDefault',
+                    'rectChecker', 'styleCursor'
+                ];
+
+            for (i = 0, len = settings.length; i < len; i++) {
+                var setting = settings[i];
+
+                this.options[setting] = defaultOptions.base[setting];
+
+                if (setting in options) {
+                    this[setting](options[setting]);
+                }
+            }
+
+            return this;
+        },
+
+        /*\
+         * Interactable.unset
+         [ method ]
+         *
+         * Remove this interactable from the list of interactables and remove
+         * it's drag, drop, resize and gesture capabilities
+         *
+         = (object) @interact
+        \*/
+        unset: function () {
+            events.remove(this._element, 'all');
+
+            if (!isString(this.selector)) {
+                events.remove(this, 'all');
+                if (this.options.styleCursor) {
+                    this._element.style.cursor = '';
+                }
+            }
+            else {
+                // remove delegated events
+                for (var type in delegatedEvents) {
+                    var delegated = delegatedEvents[type];
+
+                    for (var i = 0; i < delegated.selectors.length; i++) {
+                        if (delegated.selectors[i] === this.selector
+                            && delegated.contexts[i] === this._context) {
+
+                            delegated.selectors.splice(i, 1);
+                            delegated.contexts .splice(i, 1);
+                            delegated.listeners.splice(i, 1);
+
+                            // remove the arrays if they are empty
+                            if (!delegated.selectors.length) {
+                                delegatedEvents[type] = null;
+                            }
+                        }
+
+                        events.remove(this._context, type, delegateListener);
+                        events.remove(this._context, type, delegateUseCapture, true);
+
+                        break;
+                    }
+                }
+            }
+
+            this.dropzone(false);
+
+            interactables.splice(indexOf(interactables, this), 1);
+
+            return interact;
+        }
+    };
+
+    function warnOnce (method, message) {
+        var warned = false;
+
+        return function () {
+            if (!warned) {
+                window.console.warn(message);
+                warned = true;
+            }
+
+            return method.apply(this, arguments);
+        };
+    }
+
+    Interactable.prototype.snap = warnOnce(Interactable.prototype.snap,
+         'Interactable#snap is deprecated. See the new documentation for snapping at http://interactjs.io/docs/snapping');
+    Interactable.prototype.restrict = warnOnce(Interactable.prototype.restrict,
+         'Interactable#restrict is deprecated. See the new documentation for resticting at http://interactjs.io/docs/restriction');
+    Interactable.prototype.inertia = warnOnce(Interactable.prototype.inertia,
+         'Interactable#inertia is deprecated. See the new documentation for inertia at http://interactjs.io/docs/inertia');
+    Interactable.prototype.autoScroll = warnOnce(Interactable.prototype.autoScroll,
+         'Interactable#autoScroll is deprecated. See the new documentation for autoScroll at http://interactjs.io/docs/#autoscroll');
+    Interactable.prototype.squareResize = warnOnce(Interactable.prototype.squareResize,
+         'Interactable#squareResize is deprecated. See http://interactjs.io/docs/#resize-square');
+
+    Interactable.prototype.accept = warnOnce(Interactable.prototype.accept,
+         'Interactable#accept is deprecated. use Interactable#dropzone({ accept: target }) instead');
+    Interactable.prototype.dropChecker = warnOnce(Interactable.prototype.dropChecker,
+         'Interactable#dropChecker is deprecated. use Interactable#dropzone({ dropChecker: checkerFunction }) instead');
+    Interactable.prototype.context = warnOnce(Interactable.prototype.context,
+         'Interactable#context as a method is deprecated. It will soon be a DOM Node instead');
+
+    /*\
+     * interact.isSet
+     [ method ]
+     *
+     * Check if an element has been set
+     - element (Element) The Element being searched for
+     = (boolean) Indicates if the element or CSS selector was previously passed to interact
+    \*/
+    interact.isSet = function(element, options) {
+        return interactables.indexOfElement(element, options && options.context) !== -1;
+    };
+
+    /*\
+     * interact.on
+     [ method ]
+     *
+     * Adds a global listener for an InteractEvent or adds a DOM event to
+     * `document`
+     *
+     - type       (string | array | object) The types of events to listen for
+     - listener   (function) The function to be called on the given event(s)
+     - useCapture (boolean) #optional useCapture flag for addEventListener
+     = (object) interact
+    \*/
+    interact.on = function (type, listener, useCapture) {
+        if (isString(type) && type.search(' ') !== -1) {
+            type = type.trim().split(/ +/);
+        }
+
+        if (isArray(type)) {
+            for (var i = 0; i < type.length; i++) {
+                interact.on(type[i], listener, useCapture);
+            }
+
+            return interact;
+        }
+
+        if (isObject(type)) {
+            for (var prop in type) {
+                interact.on(prop, type[prop], listener);
+            }
+
+            return interact;
+        }
+
+        // if it is an InteractEvent type, add listener to globalEvents
+        if (contains(eventTypes, type)) {
+            // if this type of event was never bound
+            if (!globalEvents[type]) {
+                globalEvents[type] = [listener];
+            }
+            else {
+                globalEvents[type].push(listener);
+            }
+        }
+        // If non InteractEvent type, addEventListener to document
+        else {
+            events.add(document, type, listener, useCapture);
+        }
+
+        return interact;
+    };
+
+    /*\
+     * interact.off
+     [ method ]
+     *
+     * Removes a global InteractEvent listener or DOM event from `document`
+     *
+     - type       (string | array | object) The types of events that were listened for
+     - listener   (function) The listener function to be removed
+     - useCapture (boolean) #optional useCapture flag for removeEventListener
+     = (object) interact
+     \*/
+    interact.off = function (type, listener, useCapture) {
+        if (isString(type) && type.search(' ') !== -1) {
+            type = type.trim().split(/ +/);
+        }
+
+        if (isArray(type)) {
+            for (var i = 0; i < type.length; i++) {
+                interact.off(type[i], listener, useCapture);
+            }
+
+            return interact;
+        }
+
+        if (isObject(type)) {
+            for (var prop in type) {
+                interact.off(prop, type[prop], listener);
+            }
+
+            return interact;
+        }
+
+        if (!contains(eventTypes, type)) {
+            events.remove(document, type, listener, useCapture);
+        }
+        else {
+            var index;
+
+            if (type in globalEvents
+                && (index = indexOf(globalEvents[type], listener)) !== -1) {
+                globalEvents[type].splice(index, 1);
+            }
+        }
+
+        return interact;
+    };
+
+    /*\
+     * interact.enableDragging
+     [ method ]
+     *
+     * Deprecated.
+     *
+     * Returns or sets whether dragging is enabled for any Interactables
+     *
+     - newValue (boolean) #optional `true` to allow the action; `false` to disable action for all Interactables
+     = (boolean | object) The current setting or interact
+    \*/
+    interact.enableDragging = warnOnce(function (newValue) {
+        if (newValue !== null && newValue !== undefined) {
+            actionIsEnabled.drag = newValue;
+
+            return interact;
+        }
+        return actionIsEnabled.drag;
+    }, 'interact.enableDragging is deprecated and will soon be removed.');
+
+    /*\
+     * interact.enableResizing
+     [ method ]
+     *
+     * Deprecated.
+     *
+     * Returns or sets whether resizing is enabled for any Interactables
+     *
+     - newValue (boolean) #optional `true` to allow the action; `false` to disable action for all Interactables
+     = (boolean | object) The current setting or interact
+    \*/
+    interact.enableResizing = warnOnce(function (newValue) {
+        if (newValue !== null && newValue !== undefined) {
+            actionIsEnabled.resize = newValue;
+
+            return interact;
+        }
+        return actionIsEnabled.resize;
+    }, 'interact.enableResizing is deprecated and will soon be removed.');
+
+    /*\
+     * interact.enableGesturing
+     [ method ]
+     *
+     * Deprecated.
+     *
+     * Returns or sets whether gesturing is enabled for any Interactables
+     *
+     - newValue (boolean) #optional `true` to allow the action; `false` to disable action for all Interactables
+     = (boolean | object) The current setting or interact
+    \*/
+    interact.enableGesturing = warnOnce(function (newValue) {
+        if (newValue !== null && newValue !== undefined) {
+            actionIsEnabled.gesture = newValue;
+
+            return interact;
+        }
+        return actionIsEnabled.gesture;
+    }, 'interact.enableGesturing is deprecated and will soon be removed.');
+
+    interact.eventTypes = eventTypes;
+
+    /*\
+     * interact.debug
+     [ method ]
+     *
+     * Returns debugging data
+     = (object) An object with properties that outline the current state and expose internal functions and variables
+    \*/
+    interact.debug = function () {
+        var interaction = interactions[0] || new Interaction();
+
+        return {
+            interactions          : interactions,
+            target                : interaction.target,
+            dragging              : interaction.dragging,
+            resizing              : interaction.resizing,
+            gesturing             : interaction.gesturing,
+            prepared              : interaction.prepared,
+            matches               : interaction.matches,
+            matchElements         : interaction.matchElements,
+
+            prevCoords            : interaction.prevCoords,
+            startCoords           : interaction.startCoords,
+
+            pointerIds            : interaction.pointerIds,
+            pointers              : interaction.pointers,
+            addPointer            : listeners.addPointer,
+            removePointer         : listeners.removePointer,
+            recordPointer        : listeners.recordPointer,
+
+            snap                  : interaction.snapStatus,
+            restrict              : interaction.restrictStatus,
+            inertia               : interaction.inertiaStatus,
+
+            downTime              : interaction.downTimes[0],
+            downEvent             : interaction.downEvent,
+            downPointer           : interaction.downPointer,
+            prevEvent             : interaction.prevEvent,
+
+            Interactable          : Interactable,
+            interactables         : interactables,
+            pointerIsDown         : interaction.pointerIsDown,
+            defaultOptions        : defaultOptions,
+            defaultActionChecker  : defaultActionChecker,
+
+            actionCursors         : actionCursors,
+            dragMove              : listeners.dragMove,
+            resizeMove            : listeners.resizeMove,
+            gestureMove           : listeners.gestureMove,
+            pointerUp             : listeners.pointerUp,
+            pointerDown           : listeners.pointerDown,
+            pointerMove           : listeners.pointerMove,
+            pointerHover          : listeners.pointerHover,
+
+            eventTypes            : eventTypes,
+
+            events                : events,
+            globalEvents          : globalEvents,
+            delegatedEvents       : delegatedEvents,
+
+            prefixedPropREs       : prefixedPropREs
+        };
+    };
+
+    // expose the functions used to calculate multi-touch properties
+    interact.getPointerAverage = pointerAverage;
+    interact.getTouchBBox     = touchBBox;
+    interact.getTouchDistance = touchDistance;
+    interact.getTouchAngle    = touchAngle;
+
+    interact.getElementRect         = getElementRect;
+    interact.getElementClientRect   = getElementClientRect;
+    interact.matchesSelector        = matchesSelector;
+    interact.closest                = closest;
+
+    /*\
+     * interact.margin
+     [ method ]
+     *
+     * Deprecated. Use `interact(target).resizable({ margin: number });` instead.
+     * Returns or sets the margin for autocheck resizing used in
+     * @Interactable.getAction. That is the distance from the bottom and right
+     * edges of an element clicking in which will start resizing
+     *
+     - newValue (number) #optional
+     = (number | interact) The current margin value or interact
+    \*/
+    interact.margin = warnOnce(function (newvalue) {
+        if (isNumber(newvalue)) {
+            margin = newvalue;
+
+            return interact;
+        }
+        return margin;
+    },
+    'interact.margin is deprecated. Use interact(target).resizable({ margin: number }); instead.') ;
+
+    /*\
+     * interact.supportsTouch
+     [ method ]
+     *
+     = (boolean) Whether or not the browser supports touch input
+    \*/
+    interact.supportsTouch = function () {
+        return supportsTouch;
+    };
+
+    /*\
+     * interact.supportsPointerEvent
+     [ method ]
+     *
+     = (boolean) Whether or not the browser supports PointerEvents
+    \*/
+    interact.supportsPointerEvent = function () {
+        return supportsPointerEvent;
+    };
+
+    /*\
+     * interact.stop
+     [ method ]
+     *
+     * Cancels all interactions (end events are not fired)
+     *
+     - event (Event) An event on which to call preventDefault()
+     = (object) interact
+    \*/
+    interact.stop = function (event) {
+        for (var i = interactions.length - 1; i >= 0; i--) {
+            interactions[i].stop(event);
+        }
+
+        return interact;
+    };
+
+    /*\
+     * interact.dynamicDrop
+     [ method ]
+     *
+     * Returns or sets whether the dimensions of dropzone elements are
+     * calculated on every dragmove or only on dragstart for the default
+     * dropChecker
+     *
+     - newValue (boolean) #optional True to check on each move. False to check only before start
+     = (boolean | interact) The current setting or interact
+    \*/
+    interact.dynamicDrop = function (newValue) {
+        if (isBool(newValue)) {
+            //if (dragging && dynamicDrop !== newValue && !newValue) {
+                //calcRects(dropzones);
+            //}
+
+            dynamicDrop = newValue;
+
+            return interact;
+        }
+        return dynamicDrop;
+    };
+
+    /*\
+     * interact.pointerMoveTolerance
+     [ method ]
+     * Returns or sets the distance the pointer must be moved before an action
+     * sequence occurs. This also affects tolerance for tap events.
+     *
+     - newValue (number) #optional The movement from the start position must be greater than this value
+     = (number | Interactable) The current setting or interact
+    \*/
+    interact.pointerMoveTolerance = function (newValue) {
+        if (isNumber(newValue)) {
+            pointerMoveTolerance = newValue;
+
+            return this;
+        }
+
+        return pointerMoveTolerance;
+    };
+
+    /*\
+     * interact.maxInteractions
+     [ method ]
+     **
+     * Returns or sets the maximum number of concurrent interactions allowed.
+     * By default only 1 interaction is allowed at a time (for backwards
+     * compatibility). To allow multiple interactions on the same Interactables
+     * and elements, you need to enable it in the draggable, resizable and
+     * gesturable `'max'` and `'maxPerElement'` options.
+     **
+     - newValue (number) #optional Any number. newValue <= 0 means no interactions.
+    \*/
+    interact.maxInteractions = function (newValue) {
+        if (isNumber(newValue)) {
+            maxInteractions = newValue;
+
+            return this;
+        }
+
+        return maxInteractions;
+    };
+
+    interact.createSnapGrid = function (grid) {
+        return function (x, y) {
+            var offsetX = 0,
+                offsetY = 0;
+
+            if (isObject(grid.offset)) {
+                offsetX = grid.offset.x;
+                offsetY = grid.offset.y;
+            }
+
+            var gridx = Math.round((x - offsetX) / grid.x),
+                gridy = Math.round((y - offsetY) / grid.y),
+
+                newX = gridx * grid.x + offsetX,
+                newY = gridy * grid.y + offsetY;
+
+            return {
+                x: newX,
+                y: newY,
+                range: grid.range
+            };
+        };
+    };
+
+    function endAllInteractions (event) {
+        for (var i = 0; i < interactions.length; i++) {
+            interactions[i].pointerEnd(event, event);
+        }
+    }
+
+    function listenToDocument (doc) {
+        if (contains(documents, doc)) { return; }
+
+        var win = doc.defaultView || doc.parentWindow;
+
+        // add delegate event listener
+        for (var eventType in delegatedEvents) {
+            events.add(doc, eventType, delegateListener);
+            events.add(doc, eventType, delegateUseCapture, true);
+        }
+
+        if (PointerEvent) {
+            if (PointerEvent === win.MSPointerEvent) {
+                pEventTypes = {
+                    up: 'MSPointerUp', down: 'MSPointerDown', over: 'mouseover',
+                    out: 'mouseout', move: 'MSPointerMove', cancel: 'MSPointerCancel' };
+            }
+            else {
+                pEventTypes = {
+                    up: 'pointerup', down: 'pointerdown', over: 'pointerover',
+                    out: 'pointerout', move: 'pointermove', cancel: 'pointercancel' };
+            }
+
+            events.add(doc, pEventTypes.down  , listeners.selectorDown );
+            events.add(doc, pEventTypes.move  , listeners.pointerMove  );
+            events.add(doc, pEventTypes.over  , listeners.pointerOver  );
+            events.add(doc, pEventTypes.out   , listeners.pointerOut   );
+            events.add(doc, pEventTypes.up    , listeners.pointerUp    );
+            events.add(doc, pEventTypes.cancel, listeners.pointerCancel);
+
+            // autoscroll
+            events.add(doc, pEventTypes.move, listeners.autoScrollMove);
+        }
+        else {
+            events.add(doc, 'mousedown', listeners.selectorDown);
+            events.add(doc, 'mousemove', listeners.pointerMove );
+            events.add(doc, 'mouseup'  , listeners.pointerUp   );
+            events.add(doc, 'mouseover', listeners.pointerOver );
+            events.add(doc, 'mouseout' , listeners.pointerOut  );
+
+            events.add(doc, 'touchstart' , listeners.selectorDown );
+            events.add(doc, 'touchmove'  , listeners.pointerMove  );
+            events.add(doc, 'touchend'   , listeners.pointerUp    );
+            events.add(doc, 'touchcancel', listeners.pointerCancel);
+
+            // autoscroll
+            events.add(doc, 'mousemove', listeners.autoScrollMove);
+            events.add(doc, 'touchmove', listeners.autoScrollMove);
+        }
+
+        events.add(win, 'blur', endAllInteractions);
+
+        try {
+            if (win.frameElement) {
+                var parentDoc = win.frameElement.ownerDocument,
+                    parentWindow = parentDoc.defaultView;
+
+                events.add(parentDoc   , 'mouseup'      , listeners.pointerEnd);
+                events.add(parentDoc   , 'touchend'     , listeners.pointerEnd);
+                events.add(parentDoc   , 'touchcancel'  , listeners.pointerEnd);
+                events.add(parentDoc   , 'pointerup'    , listeners.pointerEnd);
+                events.add(parentDoc   , 'MSPointerUp'  , listeners.pointerEnd);
+                events.add(parentWindow, 'blur'         , endAllInteractions );
+            }
+        }
+        catch (error) {
+            interact.windowParentError = error;
+        }
+
+        // prevent native HTML5 drag on interact.js target elements
+        events.add(doc, 'dragstart', function (event) {
+            for (var i = 0; i < interactions.length; i++) {
+                var interaction = interactions[i];
+
+                if (interaction.element
+                    && (interaction.element === event.target
+                        || nodeContains(interaction.element, event.target))) {
+
+                    interaction.checkAndPreventDefault(event, interaction.target, interaction.element);
+                    return;
+                }
+            }
+        });
+
+        if (events.useAttachEvent) {
+            // For IE's lack of Event#preventDefault
+            events.add(doc, 'selectstart', function (event) {
+                var interaction = interactions[0];
+
+                if (interaction.currentAction()) {
+                    interaction.checkAndPreventDefault(event);
+                }
+            });
+
+            // For IE's bad dblclick event sequence
+            events.add(doc, 'dblclick', doOnInteractions('ie8Dblclick'));
+        }
+
+        documents.push(doc);
+    }
+
+    listenToDocument(document);
+
+    function indexOf (array, target) {
+        for (var i = 0, len = array.length; i < len; i++) {
+            if (array[i] === target) {
+                return i;
+            }
+        }
+
+        return -1;
+    }
+
+    function contains (array, target) {
+        return indexOf(array, target) !== -1;
+    }
+
+    function matchesSelector (element, selector, nodeList) {
+        if (ie8MatchesSelector) {
+            return ie8MatchesSelector(element, selector, nodeList);
+        }
+
+        // remove /deep/ from selectors if shadowDOM polyfill is used
+        if (window !== realWindow) {
+            selector = selector.replace(/\/deep\//g, ' ');
+        }
+
+        return element[prefixedMatchesSelector](selector);
+    }
+
+    function matchesUpTo (element, selector, limit) {
+        while (isElement(element)) {
+            if (matchesSelector(element, selector)) {
+                return true;
+            }
+
+            element = parentElement(element);
+
+            if (element === limit) {
+                return matchesSelector(element, selector);
+            }
+        }
+
+        return false;
+    }
+
+    // For IE8's lack of an Element#matchesSelector
+    // taken from http://tanalin.com/en/blog/2012/12/matches-selector-ie8/ and modified
+    if (!(prefixedMatchesSelector in Element.prototype) || !isFunction(Element.prototype[prefixedMatchesSelector])) {
+        ie8MatchesSelector = function (element, selector, elems) {
+            elems = elems || element.parentNode.querySelectorAll(selector);
+
+            for (var i = 0, len = elems.length; i < len; i++) {
+                if (elems[i] === element) {
+                    return true;
+                }
+            }
+
+            return false;
+        };
+    }
+
+    // requestAnimationFrame polyfill
+    (function() {
+        var lastTime = 0,
+            vendors = ['ms', 'moz', 'webkit', 'o'];
+
+        for(var x = 0; x < vendors.length && !realWindow.requestAnimationFrame; ++x) {
+            reqFrame = realWindow[vendors[x]+'RequestAnimationFrame'];
+            cancelFrame = realWindow[vendors[x]+'CancelAnimationFrame'] || realWindow[vendors[x]+'CancelRequestAnimationFrame'];
+        }
+
+        if (!reqFrame) {
+            reqFrame = function(callback) {
+                var currTime = new Date().getTime(),
+                    timeToCall = Math.max(0, 16 - (currTime - lastTime)),
+                    id = setTimeout(function() { callback(currTime + timeToCall); },
+                  timeToCall);
+                lastTime = currTime + timeToCall;
+                return id;
+            };
+        }
+
+        if (!cancelFrame) {
+            cancelFrame = function(id) {
+                clearTimeout(id);
+            };
+        }
+    }());
+
+    /* global exports: true, module, define */
+
+    // http://documentcloud.github.io/underscore/docs/underscore.html#section-11
+    if (typeof exports !== 'undefined') {
+        if (typeof module !== 'undefined' && module.exports) {
+            exports = module.exports = interact;
+        }
+        exports.interact = interact;
+    }
+    // AMD
+    else if (typeof define === 'function' && define.amd) {
+        define('interact', function() {
+            return interact;
+        });
+    }
+    else {
+        realWindow.interact = interact;
+    }
+
+} (typeof window === 'undefined'? undefined : window));
diff --git a/sourcing/static/js/viewer.js b/sourcing/static/js/viewer.js
new file mode 100644
index 0000000..5414075
--- /dev/null
+++ b/sourcing/static/js/viewer.js
@@ -0,0 +1,397 @@
+'use strict';
+
+var doc1 = document.getElementById('doc1');
+var edlform = document.getElementById('edlform');
+var max_zindex = 0;
+var bridge_count = 0;
+var link_bridge_count = 0;
+var payment_params = {};
+var payment_content;
+var xnb_per_char = 150000;
+
+function listener (event) {
+    console.log(event.type, event.pageX, event.pageY);
+}
+
+function hl_location(hl) {
+    var rects = hl.getClientRects();
+    var top = rects[0].top;
+    var right = rects[0].right;
+    var bottom = rects[rects.length-1].bottom
+    var left = rects[rects.length-1].left;
+    console.log(top, right, bottom, left);
+}
+
+function dragMoveListener (event) {
+    var target = event.target,
+        // keep the dragged position in the data-x/data-y attributes
+        x = (parseFloat(target.getAttribute('data-x')) || 0) + event.dx,
+        y = (parseFloat(target.getAttribute('data-y')) || 0) + event.dy;
+
+    update_location(target, x, y);
+
+    update();
+}
+
+function update() {
+    for(var i = 0; i < bridge_count; i++) {
+        update_bridge('bridge' + i, 'span' + i, 'transclusion' + i);
+    }
+
+    for(var i = 0; i < link_bridge_count; i++) {
+        update_bridge('linkbridge' + i, 'xanalink' + i, 'link' + i);
+    }
+}
+
+function update_bridge(bridge, name_h1, name_h2) {
+    var points = []
+
+    var h1 = document.getElementById(name_h1);
+    var h2 = document.getElementById(name_h2);
+
+    if (!h1) {
+        return;
+    }
+    if (!h2) {
+        return;  // because we skipped the large document
+    }
+
+
+    var rect1 = h1.getBoundingClientRect();
+    var rect2 = h2.getBoundingClientRect();
+
+    var h1_x_center = rect1.right - rect1.width / 2;
+    var h2_x_center = rect2.right - rect2.width / 2;
+
+    var bridge_element = document.getElementById(bridge);
+
+    var h_l, h_r, rect_l, rect_r;
+    if (h1_x_center < h2_x_center) {
+        h_l = h1;
+        h_r = h2;
+        rect_l = rect1;
+        rect_r = rect2;
+    } else {
+        h_l = h2;
+        h_r = h1;
+        rect_l = rect2;
+        rect_r = rect1;
+    }
+
+    var body_l = $(h_l).closest(".body").get(0).getBoundingClientRect();
+    var body_r = $(h_r).closest(".body").get(0).getBoundingClientRect();
+
+    var left_bottom = rect_l.bottom;
+    if(left_bottom < body_l.top) {
+        left_bottom = body_l.top;
+    } else if (left_bottom > body_l.bottom) {
+        left_bottom = body_l.bottom;
+    }
+
+    var left_top = rect_l.top;
+    if(left_top < body_l.top) {
+        left_top = body_l.top;
+    } else if (left_top > body_l.bottom) {
+        left_top = body_l.bottom;
+    }
+
+    var right_bottom = rect_r.bottom;
+    if(right_bottom < body_r.top) {
+        right_bottom = body_r.top;
+    } else if (right_bottom > body_r.bottom) {
+        right_bottom = body_r.bottom;
+    }
+
+    var right_top = rect_r.top;
+    if(right_top < body_r.top) {
+        right_top = body_r.top;
+    } else if (right_top > body_r.bottom) {
+        right_top = body_r.bottom;
+    }
+
+    points.push(rect_l.right + ',' + left_top);
+    points.push(rect_l.right  + ',' + left_bottom);
+
+    points.push(rect_r.left  + ',' + right_bottom);
+    points.push(rect_r.left + ',' + right_top);
+
+    var poly = document.getElementById(bridge);
+    poly.setAttribute('points', points.join(' '));
+}
+
+function update_location(target, x, y) {
+    // target.style.transform = 'scale(0.75) translate(' + x + 'px, ' + y + 'px)';
+    target.style.transform = 'translate(' + x + 'px, ' + y + 'px)';
+
+    target.setAttribute('data-x', x);
+    target.setAttribute('data-y', y);
+
+    max_zindex += 1;
+    target.style.zIndex = max_zindex;
+}
+
+function resizemove(event) {
+    var target = event.target,
+            x = (parseFloat(target.getAttribute('data-x')) || 0),
+            y = (parseFloat(target.getAttribute('data-y')) || 0);
+
+    // update the element's style
+    target.style.width  = event.rect.width + 'px';
+    target.style.height = event.rect.height + 'px';
+
+    // translate when resizing from top or left edges
+    x += event.deltaRect.left;
+    y += event.deltaRect.top;
+
+    update_location(target, x, y);
+
+    update();
+}
+
+interact('.document')
+    .draggable({
+        onmove: dragMoveListener,
+    })
+    .resizable({
+        // preserveAspectRatio: false,
+        edges: { left: true, right: true, bottom: true, top: true },
+    })
+    .on('resizemove', resizemove)
+    .actionChecker(function (pointer, event, action, interactable, element, interaction) {
+        if (!interact.matchesSelector(event.target, '.heading') && action.name == 'drag') {
+            return;
+        }
+        return action;
+    });
+
+interact('#edlform')
+    .draggable({
+        onmove: dragMoveListener,
+    })
+    .on('resizemove', resizemove)
+    .actionChecker(function (pointer, event, action, interactable, element, interaction) {
+        if (!interact.matchesSelector(event.target, '.heading') && action.name == 'drag') {
+            return;
+        }
+        return action;
+    });
+
+// doc1.style.height = '400px';
+// update_location(doc1, 200, 50);
+
+var docid = 0;
+
+function new_document(doc) {
+    var source   = $("#document-template").html();
+    var template = Handlebars.compile(source);
+    docid++;
+    var context  = {
+        docid: docid,
+        heading: doc.heading,
+        doctype: doc.doctype,
+        text: doc.text
+    };
+    var element = $(template(context));
+    var w = document.documentElement.clientWidth;
+    var h = document.documentElement.clientHeight;
+
+    if (doc.doctype == 'xanadoc') {
+      var x = (w / 2) - 400;
+      var y = (h / 2) - 400;
+    } else {
+      var x = Math.random() * (w - 400);
+      var y = Math.random() * (h - 400);
+    }
+    update_location(element.get(0), x, y);
+
+    $("#top").append(element);
+}
+
+function reset() {
+    $(".document").remove();
+
+    var svg = document.getElementById('svg');
+    while (svg.firstChild) {
+        svg.removeChild(svg.firstChild);
+    }
+
+    bridge_count = 0;
+    link_bridge_count = 0;
+}
+
+$("button#clear").click(function(event) {
+    $("#edl").val("");
+    reset();
+});
+
+function get_end_number(str) {
+    var len = str.length;
+    var num;
+    for(var i = 0; i < len; i++) {
+        if(!isNaN(num = parseInt(str.substr(i))))
+            return num;
+    }
+    throw "no number found";
+}
+
+function hover_bridge(element, hover) {
+    var num = get_end_number(element.id);
+    var bridge = document.getElementById('bridge' + num);
+
+    bridge.setAttribute("class", hover ? 'hoverbridge' : 'bridge');
+
+    var cls = 'hovertransclusion';
+
+    if (hover) {
+        $('#transclusion' + num).addClass(cls);
+        $('#span' + num).addClass(cls);
+    } else {
+        $('#transclusion' + num).removeClass(cls);
+        $('#span' + num).removeClass(cls);
+    }
+}
+
+function hover_link_bridge(element, hover) {
+    var num = get_end_number(element.id);
+    var bridge = document.getElementById('linkbridge' + num);
+
+    bridge.setAttribute("class", hover ? 'hoverlinkbridge' : 'linkbridge');
+
+    var cls = 'hoverlink';
+
+    if (hover) {
+        $('#xanalink' + num).addClass(cls);
+        $('#link' + num).addClass(cls);
+    } else {
+        $('#xanalink' + num).removeClass(cls);
+        $('#link' + num).removeClass(cls);
+    }
+}
+
+function fulfil() {
+    reset();  // clear all documents and bridges
+
+    bridge_count = doc.span_count;
+    link_bridge_count = doc.link_count;
+    var svg_element = document.getElementById('svg');
+
+    for(var i = 0; i < doc.span_count; i++) {
+        var p = document.createElementNS('http://www.w3.org/2000/svg', 'polygon');
+        p.setAttribute('id', 'bridge' + i);
+        p.setAttribute('class', 'bridge');
+        p.setAttribute('visibility', 'hidden');
+
+        p.addEventListener('mouseover', function(e) {
+            hover_bridge(this, true);
+        });
+
+        p.addEventListener('mouseout', function(e) {
+            hover_bridge(this, false);
+        });
+
+        svg_element.appendChild(p);
+    }
+
+    for(var i = 0; i < doc.link_count; i++) {
+        var p = document.createElementNS('http://www.w3.org/2000/svg', 'polygon');
+        p.setAttribute('id', 'linkbridge' + i);
+        p.setAttribute('class', 'linkbridge');
+        p.setAttribute('visibility', 'hidden');
+
+        p.addEventListener('mouseover', function(e) {
+            hover_link_bridge(this, true);
+        });
+
+        p.addEventListener('mouseout', function(e) {
+            hover_link_bridge(this, false);
+        });
+
+        svg_element.appendChild(p);
+    }
+
+    $.each(doc.source, function(key, doc) {
+        if (doc.text) {
+            doc.heading += " (source document)";
+            doc.doctype = 'sourcedoc';
+            new_document(doc);
+        }
+    });
+    new_document({'heading': 'xanadoc',
+                  'text': doc.doc,
+                  'doctype': 'xanadoc'});
+
+    update();
+
+    $('.transclusion').bind('mouseover', function(e) {
+        hover_bridge(this, true);
+    });
+
+    $('.transclusion').bind('mouseout', function(e) {
+        hover_bridge(this, false);
+    });
+
+    $('.link').bind('mouseover', function(e) {
+        hover_link_bridge(this, true);
+    });
+
+    $('.link').bind('mouseout', function(e) {
+        hover_link_bridge(this, false);
+    });
+
+    $('.xanadoclink').click(function(e) {
+        var num = get_end_number(this.id);
+        var source = $('#link' + num).closest( ".sourcedoc" );
+
+        var bridge1 = document.getElementById('linkbridge' + num);
+        var cur_state = bridge1.getAttribute('visibility');
+        var new_state = cur_state == 'hidden' ? 'visible' : 'hidden';
+
+        source.find('.sourcedoclink').each(function(index, value) {
+            var bridge_num = get_end_number(value.id);
+            var bridge = document.getElementById('linkbridge' + bridge_num);
+            bridge.setAttribute('visibility', new_state);
+        });
+
+        source.toggle();
+
+        update();
+    });
+
+    $('.xanadoctransclusion').click(function(e) {
+        var num = get_end_number(this.id);
+        var source = $('#transclusion' + num).closest( ".sourcedoc" );
+
+        var bridge1 = document.getElementById('bridge' + num);
+        var cur_state = bridge1.getAttribute('visibility');
+        var new_state = cur_state == 'hidden' ? 'visible' : 'hidden';
+
+        source.find('.sourcedoctransclusion').each(function(index, value) {
+            var bridge_num = get_end_number(value.id);
+            var bridge = document.getElementById('bridge' + bridge_num);
+            bridge.setAttribute('visibility', new_state);
+        });
+
+        source.toggle();
+
+        update();
+    });
+
+    $('.body').bind('scroll', function(event) {
+        update();
+    });
+
+    $('.sourcedoc').hide();
+}
+
+function size_svg() {
+    var w = document.documentElement.clientWidth - 10;
+    var h = document.documentElement.clientHeight - 10;
+    $('svg').width(w);
+    $('svg').height(h);
+}
+
+$(function() {
+    size_svg();
+    $(window).resize(size_svg);
+    fulfil();
+});
diff --git a/sourcing/templates/head.html b/sourcing/templates/head.html
index 3ff6f28..1024ef2 100644
--- a/sourcing/templates/head.html
+++ b/sourcing/templates/head.html
@@ -7,6 +7,7 @@
 <title>{{ title | default("Xanadu") }}</title>
 
 <link rel="stylesheet" href="{{ url_for('static', filename='bootstrap/css/bootstrap.css') }}">
+{{ style | safe }}
 </head>
 
 <body>
diff --git a/sourcing/templates/view.html b/sourcing/templates/view.html
index 628bc2d..5f38166 100644
--- a/sourcing/templates/view.html
+++ b/sourcing/templates/view.html
@@ -11,6 +11,9 @@ div#text { font-family: Courier; }
       {% if doc.user == current_user %}
       <a href="{{ doc.edit_url }}" class="btn btn-default">edit</a>
       {% endif %}
+      {% if doc.type == 'xanadoc' %}
+      <a href="{{ doc.url }}" class="btn btn-default">fulfil</a>
+      {% endif %}
     </h1>
     <p><a href="{{ url_for('.home') }}">back to index</a></p>
     <div class="well" id="text">
diff --git a/sourcing/templates/view/xanadoc.html b/sourcing/templates/view/xanadoc.html
new file mode 100644
index 0000000..3ff47fa
--- /dev/null
+++ b/sourcing/templates/view/xanadoc.html
@@ -0,0 +1,53 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+<meta charset="utf-8">
+<meta http-equiv="X-UA-Compatible" content="IE=edge">
+<meta name="viewport" content="width=device-width, initial-scale=1">
+<title>{{ title | default("Xanadu") }}</title>
+
+<link rel="stylesheet" href="{{ url_for('static', filename='bootstrap/css/bootstrap.css') }}">
+<link rel="stylesheet" href="{{ url_for('static', filename='css/xanadoc.css') }}">
+</head>
+
+<body>
+{% include "navbar.html" %}
+<div class="container-fluid">
+{% include "flash_msg.html" %}
+
+{% raw %}
+<script id="document-template" type="text/x-handlebars-template">
+    <div class="document {{ doctype }}" id="doc{{ docid }}">
+        <div class="heading" id="head{{ docid }}">{{ heading }}</div>
+        <div class="wrapper">
+            <div class="body" id="body{{ docid }}">
+                {{{ text }}}
+            </div>
+        </div>
+    </div>
+</script>
+{% endraw %}
+
+<svg id="svg" version="1.2" xmlns="http://www.w3.org/2000/svg">
+</svg>
+
+<div id="top">
+
+<a href="{{ item.url + '/edl' }}" class="btn btn-default">view EDL</a>
+
+</div>
+
+<script src="{{ url_for('static', filename='jquery/jquery.js') }}"></script>
+<script src="{{ url_for('static', filename='bootstrap/js/bootstrap.js') }}"></script>
+
+<script>
+var get_span_path = "{{ url_for('.get_span') }}";
+var doc = {{ doc | tojson }};
+</script>
+
+<script src="{{ url_for('static', filename='js/interact.js') }}"></script>
+<script src="{{ url_for('static', filename='js/viewer.js') }}"></script>
+<script src="{{ url_for('static', filename='handlebars/handlebars.js') }}"></script>
+
+</body>
+</html>
diff --git a/sourcing/url.py b/sourcing/url.py
new file mode 100644
index 0000000..a8d7dc9
--- /dev/null
+++ b/sourcing/url.py
@@ -0,0 +1,45 @@
+import requests
+from .model import Item
+import os.path
+import re
+
+project_dir = os.path.dirname(os.path.dirname(__file__))
+cache_location = os.path.join(project_dir, 'cache')
+
+re_colon_slash = re.compile('[/:]+')
+
+def url_filename(url):
+    return re_colon_slash.sub('_', url)
+
+def get_text(url):
+    # assume UTF-8
+
+    text = get_url(url)
+
+    heading = url.rsplit('/', 1)[-1]
+    return {
+        'url': url,
+        'text': text,
+        'heading': heading,
+        'length': len(text),
+    }
+
+def get_url(url):
+    print('get_url:', url)
+    item = Item.from_external(url)
+    if item:
+        return item.text
+    content = requests.get(url).content
+    return content.decode(errors='replace')
+
+    filename = os.path.join(cache_location, url_filename(url))
+
+    if os.path.exists(filename):
+        content = open(filename, 'rb').read()
+    else:
+        content = requests.get(url).content
+        open(filename, 'wb').write(content)
+
+    return content.decode(errors='replace')
+
+
diff --git a/sourcing/view.py b/sourcing/view.py
index 307bbf4..0828a31 100644
--- a/sourcing/view.py
+++ b/sourcing/view.py
@@ -5,6 +5,8 @@ from flask_login import (login_user, current_user, logout_user,
 from .forms import (LoginForm, SignupForm, AccountSettingsForm,
                     UploadSourceDocForm, SourceDocForm, ItemForm)
 from .model import User, SourceDoc, Item, XanaDoc, XanaLink
+from .url import get_url
+from .edl import fulfil_edl_with_sources
 from .database import session
 from .text import iter_lines
 from werkzeug.debug.tbtools import get_current_traceback
@@ -122,10 +124,27 @@ def get_item(username, hashid):
         doc = None
     return doc if doc else abort(404)
 
+def view_xanadoc(item):
+    return render_template('view/xanadoc.html',
+                           item=item,
+                           doc=fulfil_edl_with_sources(item.text))
+
+@bp.route('/<username>/<hashid>/edl')
+def view_edl(username, hashid):
+    item = get_item(username, hashid)
+    if item.type != 'xanadoc':
+        return abort(404)
+
+    return render_template('view.html', doc=item, iter_lines=iter_lines)
+
 @bp.route('/<username>/<hashid>')
 def view_item(username, hashid):
+    item = get_item(username, hashid)
+    if item.type == 'xanadoc':
+        return view_xanadoc(item)
+
     return render_template('view.html',
-                           doc=get_item(username, hashid),
+                           doc=item,
                            iter_lines=iter_lines)
 
 @bp.route('/<username>/<hashid>/edit', methods=['GET', 'POST'])
@@ -224,9 +243,11 @@ def api_get_document(username, filename):
     }
     return jsonify(ret)
 
-@bp.route('/all_titles')
-def get_all_titles():
-    titles = XanaLink.get_all_titles()
-    for k, v in titles.items():
-        print(from_external(k), v)
-    return ''
+@bp.route('/get_span.json')
+def get_span():
+    url = request.args['url']
+    start = int(request.args['start'])
+    length = int(request.args['length'])
+    spanid = request.args['spanid']
+    text = get_url(url)
+    return jsonify(text=text[start:start + length], spanid=spanid)