from django.contrib import messages
from django.contrib.auth import authenticate, get_user_model, login
from django.core.exceptions import PermissionDenied
from django.http import Http404
from django.shortcuts import get_object_or_404, redirect, render
from django.utils import timezone
from django.utils.formats import date_format
from django.utils.translation import ugettext as _
from django.views.decorators.cache import never_cache
from django.views.decorators.debug import sensitive_post_parameters

from misago.conf import settings
from misago.core.mail import mail_user

from misago.users.bans import ban_ip
from misago.users.decorators import deny_authenticated, deny_banned_ips
from misago.users.forms.register import RegisterForm
from misago.users.models import (ACTIVATION_REQUIRED_USER,
                                 ACTIVATION_REQUIRED_ADMIN)
from misago.users.tokens import make_activation_token
from misago.users.validators import validate_new_registration


def register_decorator(f):
    def decorator(request):
        if settings.account_activation == 'disabled':
            return register_disabled(request)
        else:
            return f(request)
    return decorator


@sensitive_post_parameters("email", "password")
@never_cache
@deny_authenticated
@deny_banned_ips
@register_decorator
def register(request):
    SecuredForm = add_captcha_to_form(RegisterForm, request)

    form = SecuredForm()
    if request.method == 'POST':
        form = SecuredForm(request.POST)
        if form.is_valid():
            try:
                validate_new_registration(
                    request.user.ip,
                    form.cleaned_data['username'],
                    form.cleaned_data['email'])
            except PermissionDenied as e:
                staff_message = _("This ban was automatically imposed on "
                                  "%(date)s due to denied register attempt.")

                message_formats = {'date': date_format(timezone.now())}
                staff_message = staff_message % message_formats
                ban_ip(request.user.ip,
                       staff_message=staff_message,
                       length={'days': 1})
                raise e

            activation_kwargs = {}
            if settings.account_activation == 'user':
                activation_kwargs = {
                    'requires_activation': ACTIVATION_REQUIRED_USER
                }
            elif settings.account_activation == 'admin':
                activation_kwargs = {
                    'requires_activation': ACTIVATION_REQUIRED_ADMIN
                }

            User = get_user_model()
            new_user = User.objects.create_user(form.cleaned_data['username'],
                                                form.cleaned_data['email'],
                                                form.cleaned_data['password'],
                                                set_default_avatar=True,
                                                **activation_kwargs)

            mail_subject = _("Welcome on %(forum_title)s forums!")
            mail_subject = mail_subject % {'forum_title': settings.forum_name}

            if settings.account_activation == 'none':
                authenticated_user = authenticate(
                    username=new_user.email,
                    password=form.cleaned_data['password'])
                login(request, authenticated_user)

                welcome_message = _("Welcome aboard, %(user)s!")
                welcome_message = welcome_message % {'user': new_user.username}
                messages.success(request, welcome_message)

                mail_user(request, new_user, mail_subject,
                          'misago/emails/register/complete')

                return redirect(settings.LOGIN_REDIRECT_URL)
            else:
                activation_token = make_activation_token(new_user)

                activation_by_admin = new_user.requires_activation_by_admin
                activation_by_user = new_user.requires_activation_by_user

                mail_user(
                    request, new_user, mail_subject,
                    'misago/emails/register/inactive',
                    {
                        'activation_token': activation_token,
                        'activation_by_admin': activation_by_admin,
                        'activation_by_user': activation_by_user,
                    })

                request.session['registered_user'] = new_user.pk
                return redirect('misago:register_completed')

    return render(request, 'misago/register/form.html', {'form': form})


def register_disabled(request):
    return render(request, 'misago/register/disabled.html')


def register_completed(request):
    """
    If user needs to activate his account, we display him page with message
    """
    registered_user_pk = request.session.get('registered_user')
    if not registered_user_pk:
        raise Http404()

    registered_user = get_object_or_404(get_user_model().objects,
                                        pk=registered_user_pk)

    if not registered_user.requires_activation:
        return redirect('misago:index')

    activation_by_admin = registered_user.requires_activation_by_admin
    activation_by_user = registered_user.requires_activation_by_user

    return render(
        request,
        'misago/register/completed.html',
        {
            'activation_by_admin': activation_by_admin,
            'activation_by_user': activation_by_user,
            'registered_user': registered_user,
        })