#!/usr/bin/python3

"""Web page to show upcoming events."""

import inspect
import operator
import os.path
import sys
import traceback
from datetime import date, datetime

import flask
import werkzeug
import werkzeug.debug.tbtools
import yaml

import agenda.data
import agenda.error_mail
import agenda.travel

app = flask.Flask(__name__)
app.debug = False
app.config.from_object("config.default")

agenda.error_mail.setup_error_mail(app)


@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 = werkzeug.debug.tbtools.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("/")
async def index() -> str:
    """Index page."""
    now = datetime.now()
    data = await agenda.data.get_data(now, app.config)

    return flask.render_template("index.html", today=now.date(), **data)


@app.route("/gaps")
async def gaps_page() -> str:
    """List of available gaps."""
    now = datetime.now()
    data = await agenda.data.get_data(now, app.config)
    return flask.render_template("gaps.html", today=now.date(), gaps=data["gaps"])


@app.route("/travel")
def travel_list() -> str:
    """Page showing a list of upcoming travel."""
    data_dir = app.config["PERSONAL_DATA"]
    flights = agenda.travel.parse_yaml("flights", data_dir)
    trains = agenda.travel.parse_yaml("trains", data_dir)

    return flask.render_template("travel.html", flights=flights, trains=trains)


def as_date(d: date | datetime) -> date:
    """Date of event."""
    return d.date() if isinstance(d, datetime) else d


@app.route("/conference")
def conference_list() -> str:
    """Page showing a list of conferences."""
    data_dir = app.config["PERSONAL_DATA"]
    filepath = os.path.join(data_dir, "conferences.yaml")
    item_list = yaml.safe_load(open(filepath))["conferences"]
    today = date.today()
    for conf in item_list:
        conf["start_date"] = as_date(conf["start"])
        conf["end_date"] = as_date(conf["end"])

    item_list.sort(key=operator.itemgetter("start_date"))

    current = [
        conf
        for conf in item_list
        if conf["start_date"] <= today and conf["end_date"] >= today
    ]

    past = [conf for conf in item_list if conf["end_date"] < today]
    future = [conf for conf in item_list if conf["start_date"] > today]

    return flask.render_template(
        "conference_list.html", current=current, past=past, future=future, today=today
    )


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