from django.shortcuts import render, redirect
from django.urls import reverse
from django.contrib.auth import logout as auth_logout
from django.contrib.auth.decorators import login_required

from urllib.parse import quote as urlquote


def login(req):
    if req.user.is_authenticated():
        return redirect('homepage')

    if req.method == 'GET':
        reqDict = req.GET
    elif req.method == 'POST':
        reqDict = req.POST
    if 'next' in reqDict:
        nextUrl = reqDict['next']
        context = {
            'pass_url': '{}?next={}'.format(
                reverse('password_login'),
                urlquote(nextUrl, safe='')),
            'cas_url': '{}?next={}'.format(
                reverse('cas_ng_login'),
                urlquote(nextUrl, safe='')),
        }
    else:
        context = {
            'pass_url': reverse('password_login'),
            'cas_url': reverse('cas_ng_login'),
        }

    return render(req, 'mainsite/login.html', context=context)


@login_required
def logout(req):
    CAS_BACKEND_NAME = 'django_cas_ng.backends.CASBackend'
    if req.session['_auth_user_backend'] != CAS_BACKEND_NAME:
        auth_logout(req)
        return redirect('homepage')
    return redirect('cas_ng_logout')