import json

import asyncio

from init import db, Meals, scheduler, flaskApp
import datetime
import time
import httpx

nomeal = 'Essen nicht (mehr) verfügbar'


async def getMeals(day: datetime):
    """
    Liefert alle Mahlzeiten eines Tages. \n
    Befinden sie sich schon in der Datenbank, werden diese zurückgegeben. \n
    Wenn nicht, wird getMealsFromAPI() aufgerufen. \n
    :param day:
    :return [Name1, Name2, ...]:
    """
    day = formatDay(day)
    essen = []
    query = Meals.query.filter_by(date=day).all()
    if len(query) != 0:
        for i in query:
            essen += [i.name]
        essen.sort(key=len, reverse=True)
        return essen
    return await getMealsFromAPI(day, dbentry=True)


async def getMealsFromAPI(day: str, dbentry: bool = False):
    """
    Fragt die Mensa-API nach den Mahlzeiten eines Tages ab. \n
    Wenn dbentry: Schreibt die Ergebnisse in die Datenbank. \n
    TODO: Andere Mensen berücksichtigen.
    :param day:
    :param dbentry:
    :return [Name1, Name2, ...]:
    """
    async with httpx.AsyncClient() as s:
        response = await s.get(url=f"https://dh-api.paulmartin.cloud/plans/{day}?canteens=erzberger")
        response = response.content
        jsonResponse = json.loads(response.decode("utf-8"))
        essen = []
        try:
            number = len(jsonResponse["data"][0]["lines"])
            for i in range(number):
                try:
                    jsonMeals = jsonResponse["data"][0]["lines"][i]["meals"]
                    hasContent = True
                except IndexError:
                    essen = []
                    hasContent = False
                if hasContent:
                    for e in range(len(jsonMeals)):
                        jsonEntry = jsonMeals[e]
                        name = jsonEntry["name"]
                        if pricetofloat(jsonEntry["price"]) >= 1.1:
                            vegan = jsonEntry["classifiers"].count("VG") == 1
                            schwein = jsonEntry["classifiers"].count("S") == 1
                            if vegan:
                                vegetarian = True
                            else:
                                vegetarian = jsonEntry["classifiers"].count("VEG") == 1
                                if vegetarian:
                                    if name.count("Reibekäse") > 0:
                                        vegan = True

                            essen += [name]
                            if dbentry:
                                mid = int(time.time() * 1000) % 100000
                                neu = Meals(date=day, name=name, id=mid, vegan=vegan, vegetarian=vegetarian,
                                            schwein=schwein)
                                db.session.add(neu)
                                db.session.commit()
            if not essen:
                essen = [nomeal]
        except KeyError:
            essen = [nomeal]
        return essen


def pricetofloat(price: str):
    """
    Konvertiert den Preis-String der Mensa-API zu einem Python-Float.
    :param price:
    :return float:
    """
    price = price[:-2]
    price = price.replace(",", ".")
    try:
        return float(price)
    except ValueError:
        return 0


def formatDay(day: datetime):
    """
    Füllt ein Datum mit Nullen auf. \n
    "2023-1-1" → "2023-01-01".
    :param day:
    :return str:
    """
    if day.month < 10:
        monat = "0" + str(day.month)
    else:
        monat = str(day.month)
    if day.day < 10:
        tag = "0" + str(day.day)
    else:
        tag = str(day.day)
    formattedDay = str(day.year) + "-" + monat + "-" + tag
    return formattedDay


async def refreshMeals():
    """
    Aktualisiert alle Mahlzeiten in der Datenbank. \n
    Datenbankeinträge werden ersetzt, wenn die API andere Mahlzeiten liefert.
    """
    print("Aktualisiere Essenspläne...\n")

    table = Meals.query.all()
    dates = []
    for i in table:
        if i.date not in dates:
            dates += [i.date]
    for i in range(len(dates)):
        dates[i] = formatDay(dates[i])
    for i in dates:
        apiNames = await getMealsFromAPI(i)
        dbMeals = Meals.query.filter_by(date=i).all()
        dbNames = []
        for meal in dbMeals:
            dbNames += [meal.name]
        if set(dbNames) != set(apiNames) and nomeal not in apiNames:
            for name in dbNames:
                db.session.delete(Meals.query.filter_by(date=i, name=name).first())
                db.session.commit()
            await getMealsFromAPI(i, True)


@scheduler.task('cron', id="mensaSchedule", hour='8-11', day_of_week='*', minute='*/15', week='*', second='5')
def mensaSchedule():
    """
    Nutzt vormittags die Funktion refreshMeals(), um die Essen zu aktualisieren
    """
    if not flaskApp.config["TESTING"]:
        with flaskApp.app_context():
            asyncio.run(refreshMeals())