import uuid

from django.conf import settings
from django.contrib.auth import authenticate
from django.contrib.auth import login as auth_login, logout as auth_logout
from django.contrib.auth.models import User
from django.core.mail import send_mail
from django.core.urlresolvers import reverse
from django.http import HttpResponseBadRequest
from django.shortcuts import redirect, render

from hc.accounts.forms import EmailForm
from hc.api.models import Check


def _make_user(email):
    username = str(uuid.uuid4())[:30]
    user = User(username=username, email=email)
    user.save()

    return user


def _associate_demo_check(request, user):
    if "welcome_code" in request.session:
        check = Check.objects.get(code=request.session["welcome_code"])
        check.user = user
        check.save()


def login(request):
    if request.method == 'POST':
        form = EmailForm(request.POST)
        if form.is_valid():
            email = form.cleaned_data["email"]
            try:
                user = User.objects.get(email=email)
            except User.DoesNotExist:
                user = _make_user(email)
                _associate_demo_check(request, user)

            # We don't want to reset passwords of staff users :-)
            if user.is_staff:
                return HttpResponseBadRequest()

            token = str(uuid.uuid4())
            user.set_password(token)
            user.save()

            login_link = reverse("hc-check-token", args=[user.username, token])
            login_link = settings.SITE_ROOT + login_link
            body = "login link: %s" % login_link

            send_mail('Log In', body, 'cuu508@gmail.com', [email],
                      fail_silently=False)

            return redirect("hc-login-link-sent")

    else:
        form = EmailForm()

    ctx = {"form": form}
    return render(request, "accounts/login.html", ctx)


def logout(request):
    auth_logout(request)
    return redirect("hc-index")


def login_link_sent(request):
    return render(request, "accounts/login_link_sent.html")


def check_token(request, username, token):
    user = authenticate(username=username, password=token)
    if user is not None:
        if user.is_active:
            user.set_unusable_password()
            user.save()
            auth_login(request, user)
            return redirect("hc-checks")

    return render(request, "bad_link.html")