import time

import asyncio
import icalendar
import datetime
import recurring_ical_events
from fetchMENSA import getMeals
import pytz

shortnames = ["mon", "tue", "wed", "thu", "fri", "sat"]
longnames = ["Montag", "Dienstag", "Mittwoch", "Donnerstag", "Freitag", "Samstag"]
months = ["Januar", "Februar", "März", "April", "Mai", "Juni", "Juli", "August", "September", "Oktober",
          "November", "Dezember"]


async def getWeek(weekstart: datetime, file: str, showsat: bool):
    """
    Liefert alle Events einer Woche zurück. \n
    Wochenstart wird automatisch auf den Montag der Woche gelegt. \n
    :param weekstart:
    :param file:
    :param showsat:
    :return:
    """
    if weekstart == "today":
        start_date = datetime.date.today()
    else:
        start_date = weekstart
    nextw = start_date + datetime.timedelta(weeks=1)
    prevw = start_date - datetime.timedelta(weeks=1)
    start_date -= datetime.timedelta(days=start_date.weekday() % 7)
    end_date = start_date + datetime.timedelta(days=6)
    mon = months[start_date.month - 1]
    if start_date.month != end_date.month:
        if start_date.year != end_date.year:
            mon += " " + str(start_date.year) + " | " + months[end_date.month - 1]
        else:
            mon += " | " + months[end_date.month-1]

    mon += " " + str(end_date.year)
    with open("calendars/" + file) as f:
        calendar = icalendar.Calendar.from_ical(f.read())

    events = recurring_ical_events.of(calendar).between(start_date, end_date)
    eventl = []

    for event in events:
        estart = event["DTSTART"].dt
        if str(estart.tzinfo) != "Europe/Berlin":
            estart = estart.astimezone(pytz.timezone("Europe/Berlin"))
        formstart = str(estart.hour) + ":" + str(estart.minute)
        eend = event["DTEND"].dt
        if str(eend.tzinfo) != "Europe/Berlin":
            eend = eend.astimezone(pytz.timezone("Europe/Berlin"))
        formend = str(eend.hour) + ":" + str(eend.minute)
        forml = [formstart, formend]
        for i in range(2):
            if len(forml[i]) != 5:
                if forml[i][-2] == ":":
                    forml[i] = forml[i] + "0"
                if forml[i][1] == ":":
                    forml[i] = "0" + forml[i]
        formstart = forml[0]
        formend = forml[1]
        try:
            if type(event["ATTENDEE"]) is not list:
                teacher = [event["ATTENDEE"].params["CN"]]
            else:
                teacher = [i.params["CN"] for i in event["ATTENDEE"]]
        except KeyError:
            teacher = ""
        eventdict = {
            "start": formstart,
            "end": formend,
            "dur": str(event["DTEND"].dt - event["DTSTART"].dt)[:-3],
            "name": event["SUMMARY"],
            "room": event["LOCATION"],
            "weekday": estart.weekday(),
            "day": estart.day,
            "teacher": teacher,
        }
        eventl += [eventdict]
    return eventl, await daylist(start_date, showsat), prevw, nextw, mon


async def daylist(weekstart: datetime, showsat: bool):
    """
    Gibt die Essen einer Woche zurück.
    :param weekstart:
    :param showsat:
    :return:
    """
    weekday = weekstart
    dayl = []
    if showsat:
        r = 6
    else:
        r = 5
    essen = []
    for i in range(r):
        essen += [getMeals(weekday)]
        dayl += [{
            "day": weekday.day,
            "short": shortnames[i],
            "long": longnames[i],
            "mensa": i
        }]
        weekday += datetime.timedelta(days=1)
    essenl = await asyncio.gather(*essen, return_exceptions=True)
    for day in range(r):
        dayl[day]["mensa"] = essenl[day]
    return dayl