import urllib.parse
import time
from bs4 import BeautifulSoup
from flask import redirect, url_for
from init import Dualis
import asyncio
import httpx

headers = {
    'Cookie': 'cnsc=0',
    'Content-Type': 'application/x-www-form-urlencoded',
    'User-Agent': 'Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) '
                  'Chrome/58.0.3029.110 Safari/537.36',
    'Accept-Encoding': 'utf-8'
}

url = "https://dualis.dhbw.de/scripts/mgrqispi.dll"


async def checkUser(email: str, password: str):
    """
    Erhält von Dualis den Token und Cookie für User.
    :param email:
    :param password:
    :return (Token, Cookie):
    """
    async with httpx.AsyncClient() as s:
        formattedPassword = urllib.parse.quote(password, safe='', encoding=None, errors=None)
        formattedEmail = urllib.parse.quote(email, safe='', encoding=None, errors=None)
        content = (f"usrname={formattedEmail}&pass={formattedPassword}&ARGUMENTS=clino%2Cusrname%2Cpass%2C"
                   f"menuno%2Cmenu_type%2Cbrowser%2Cplatform&APPNAME=CampusNet&PRGNAME=LOGINCHECK")
        response = await s.post(url=url, headers=headers, content=content)
        header =  response.headers
        try:
            refresh = header["REFRESH"]
            arg = refresh.find("=-N") + 3
            komma = refresh[arg:].find(",")
            cookie = s.cookies.get("cnsc")
        except KeyError:
            return -2, s
        token = refresh[arg:komma + arg]
        return token, cookie


async def getKurs(token: int, cookie: str):
    """
    Bestimmt aus der ersten Prüfung den Kursbezeichner des Users.
    TODO: Umstellen auf Bezeichner INKL. Standort
    :param token:
    :param cookie:
    :return Kurs-Bezeichner ODER 0 bei Fehler:
    """
    try:
        headers["Cookie"] = "cnsc=" + cookie
        token = str(token)
        async with httpx.AsyncClient() as s:
            response = await s.get(url=f"{url}?APPNAME=CampusNet&PRGNAME=COURSERESULTS&ARGUMENTS=-N{token},-N000307,",
                                   headers=headers)
            html = BeautifulSoup(response.text, 'lxml')
            try:
                link = html.body.find('a', attrs={'id': "Popup_details0001"})['href']
            except TypeError:
                return 0
            response = await s.get(url=f"{url}{link[21:]}", headers=headers)
            html = BeautifulSoup(response.text, 'lxml')
            content = html.body.find('td', attrs={'class': 'level02'}).text
            start = content.find(" ") + 4
            end = start + (content[start:].find(" "))
            kurs = content[start:end]
    except AttributeError:
        kurs = 0
    return kurs


async def logOut(token: int, cookie: str):
    """
    Invalidiert Token und Cookie bei Dualis.
    :param token:
    :param cookie:
    """
    headers["Cookie"] = "cnsc=" + cookie
    async with httpx.AsyncClient() as s:
        await s.get(url=f"{url}?APPNAME=CampusNet&PRGNAME=LOGOUT&ARGUMENTS=-N{token}, -N001", headers=headers)


async def getSem(token: int, cookie: str):
    """
    Liefert die Liste aller auf Dualis verfügbaren Semester.
    :param token:
    :param cookie:
    :return Liste [[Semester, Semester-ID], ...]:
    """
    headers["Cookie"] = "cnsc=" + cookie
    token = str(token)
    async with httpx.AsyncClient() as s:
        response = await s.get(url=f"{url}?APPNAME=CampusNet&PRGNAME=COURSERESULTS&ARGUMENTS=-N{token},-N000307,",
                               headers=headers)
        html = BeautifulSoup(response.text, 'lxml')
        select = html.find('select')
        select = select.find_all(value=True)
        optlist = []
        for i in select:
            text = i.text.replace("Wi", "Winter").replace("So", "Sommer")
            text = text.replace("Se", "semester")
            optlist += [[text, i['value']]]
        return optlist


async def getResults(token, cookie: str, resl: str):
    """
    Liefert die Liste aller Prüfungsergebnisse eines Semesters.
    :param token:
    :param cookie:
    :param resl:
    :return [[Name, Note, Credits], ...]:
    """
    headers["Cookie"] = "cnsc=" + cookie
    async with httpx.AsyncClient() as s:
        response = await s.get(
            url=f"{url}?APPNAME=CampusNet&PRGNAME=COURSERESULTS&ARGUMENTS=-N{token},-N000307,,-N{resl}",
            headers=headers)
        html = BeautifulSoup(response.content.decode("utf-8"), 'lxml')
        table = html.find('table', attrs={"class": "nb list"})
        body = table.find("tbody")
        vorlesungen = body.find_all("tr")
        vorlesungenList = []
        tasks = []
        i = 0
        for row in vorlesungen:
            columns = row.find_all("td")
            column = [[e.text.strip()] for e in columns]
            if len(column) != 0:
                if len(column[4][0]) == 0 or len(column[2][0]) == 0:
                    tasks += [getPruefung(s, row.find("a")["href"])]
                    column[2] = i
                    i += 1
            vorlesungenList += [column[1:4]]
        notlisted = await asyncio.gather(*tasks, return_exceptions=True)
        for i in vorlesungenList:
            for e in range(0, len(i)):
                if isinstance(i[e], int):
                    i[e] = notlisted[i[e]]
        return vorlesungenList[:-1]


async def getPruefung(s, url):
    """
    Ermittelt Noten "geschachtelter" Prüfungen, die nicht auf der Hauptseite angezeigt werden.
    TODO: Namen der spezifischen Prüfungen auch zurückgeben, um Zusammensetzung zu spezifizieren.
    :param s:
    :param url:
    :return Noten-Liste:
    """
    response = await s.get("https://dualis.dhbw.de" + url, headers=headers)
    html = BeautifulSoup(response.content.decode("utf-8"), 'lxml')
    table = html.find('table')
    pruefung = table.find_all("tr")
    returnList = []
    for row in pruefung:
        columns = row.find_all("td")
        column = [e.text.strip() for e in columns]
        if len(column) == 6 and len(column[3]) <= 13:
            if len(column[3]) != 0:
                returnList += [column[0] + ": " + column[3].split("\xa0")[0]]
                if returnList[-1][0] == ':':
                    returnList[-1] = "Gesamt" + returnList[-1]
    if len(returnList) == 0:
        returnList = ["Noch nicht gesetzt"]
    return returnList


def checkLifetime(timecode: float):
    """
    Dualis-Token laufen nach 30 Minuten ab.
    True, wenn Token noch gültig ist.
    False wenn ungültig.
    :param timecode:
    :return:
    """
    if time.time() - timecode > 1800:
        return False
    else:
        return True


def timeOut(dualis: Dualis, cookie: str, origin: str):
    """
    Checkt, ob Token und Cookie noch valide/vorhanden sind.
    False, falls alles richtig ist.
    Weiterleitung zum Login, falls nicht.
    :param dualis:
    :param cookie:
    :param origin:
    :return:
    """
    if not checkLifetime(dualis.token_created) or not cookie:
        return redirect(url_for("login", next=url_for(origin), code=10))
    else:
        return False