#!/usr/bin/python3
"""Find photos on flickr for Wikipedia articles and contact the photographer."""

import collections
import inspect
import json
import sys
import traceback
import typing
from urllib.parse import unquote

import flask
import requests
import werkzeug
from werkzeug.debug.tbtools import DebugTraceback

app = flask.Flask(__name__)
app.debug = False

enwiki = "en.wikipedia.org/wiki/"


@app.errorhandler(werkzeug.exceptions.InternalServerError)
def exception_handler(e: werkzeug.exceptions.InternalServerError) -> tuple[str, int]:
    """Handle exception."""
    exec_type, exc_value, current_traceback = sys.exc_info()
    assert exc_value
    tb = DebugTraceback(exc_value)

    summary = tb.render_traceback_html(include_title=False)
    exc_lines = "".join(tb._te.format_exception_only())

    last_frame = list(traceback.walk_tb(current_traceback))[-1][0]
    last_frame_args = inspect.getargs(last_frame.f_code)

    return (
        flask.render_template(
            "show_error.html",
            plaintext=tb.render_traceback_text(),
            exception=exc_lines,
            exception_type=tb._te.exc_type.__name__,
            summary=summary,
            last_frame=last_frame,
            last_frame_args=last_frame_args,
        ),
        500,
    )


@app.route("/")
def start() -> str:
    """Start form."""
    enwp = flask.request.args.get("enwp")
    if not enwp:
        return flask.render_template("combined.html")
    enwp = enwp.strip()
    if not enwp:
        return flask.render_template("combined.html")

    input_is = "url" if enwiki in enwp else "title"

    wikipedia_url: str
    wiki_part1: str
    wiki_part2: str
    if input_is == "url":
        start = enwp.find(enwiki) + len(enwiki)
        wiki_part2 = unquote(enwp[start:])
        name = wiki_part2
        wiki_part1 = enwp[:start]
        wikipedia_url = enwp
    else:
        name = enwp
        wiki_part1 = "https://" + enwiki
        wiki_part2 = name.replace(" ", "_")
        wikipedia_url = wiki_part1 + wiki_part2

    if "_(" in name:
        name = name[: name.find("_(")]
    name = name.replace("_", " ")

    flickr_url = flask.request.args.get("flickr")
    if not flickr_url:
        return flask.render_template(
            "combined.html",
            name=name,
            enwp=enwp,
        )

    if "/in/" in flickr_url:
        flickr_url = flickr_url[: flickr_url.find("/in/")]

    flickr_start = "https://flickr.com/photos/"

    assert flickr_url.startswith(flickr_start)
    flickr_username = flickr_url[
        len(flickr_start) : flickr_url.find("/", len(flickr_start))
    ]

    nsid = flickr_usrename_to_nsid(flickr_username)
    assert nsid
    print(nsid)

    msg = flask.render_template(
        "message.jinja",
        flickr_url=flickr_url,
        enwp=enwp,
        wikipedia_url=wikipedia_url,
        name=name,
        wiki_part1=wiki_part1,
        wiki_part2=wiki_part2,
    )

    subject = f"Request to use your photo of {name} on Wikipedia"

    lines = msg.split("\n\n")

    return flask.render_template(
        "combined.html",
        name=name,
        enwp=enwp,
        flickr_url=flickr_url,
        subject=subject,
        lines=lines,
        nsid=nsid,
    )


def get_params(line_iter: collections.abc.Iterable[str]) -> str:
    """Find and return params from flickr profile page."""
    look_for = 'params: {"isEditingTestimonial":false,'
    return next(line[line.find("{") :] for line in line_iter if look_for in line)


def flickr_usrename_to_nsid(username: str) -> str:
    """Get NSID from flickr username."""
    url = f"https://www.flickr.com/people/{username}/"
    r = requests.get(url)
    params = json.loads(get_params(r.text.splitlines()))
    return typing.cast(str, params["nsid"])


if __name__ == "__main__":
    app.run(host="0.0.0.0")