import json
import logging
import urllib.parse

from django.views.generic import View
from django.http.response import HttpResponse, HttpResponseRedirect
from django.contrib.auth import logout
from django.utils.http import is_safe_url

from .models import SingleSignOnRecord
from .settings import sso_settings


logger = logging.getLogger(__name__)


class SyncSsoUserEndpoint(View):

    def dispatch(self, request, *args, **kwargs):
        auth = request.META.get('HTTP_AUTHORIZATION', b'').split()
        if len(auth) != 2 or auth[0].lower() != 'bearer':
            return HttpResponse(status=401)
        if auth[1] != sso_settings.PU_SSO_SYNC_API_TOKEN:
            return HttpResponse(status=401)
        return super(SyncSsoUserEndpoint, self).dispatch(request, *args, **kwargs)

    def post(self, request, *args, **kwargs):
        """
        Example input:
        {
            "event": "login",
            "user": {
                "external_id": "1231-123",
                "username": "my-username",
                "email": "my@email.com",
                "phone": "13600000000"
            }
        }
        """
        try:
            data = json.loads(request.body.decode('utf-8'))
            user_external_id = data['user']['external_id']
            username = data['user']['username']
            user_email = data['user']['email']
            user_phone = data['user']['phone']
        except Exception:
            import traceback
            logger.error(traceback.format_exc())
            return HttpResponse(status=400)

        # Do nothing if user not exists
        try:
            user = SingleSignOnRecord.objects.get(external_id=user_external_id).user
        except SingleSignOnRecord.DoesNotExist:
            return HttpResponse(status=200)

        user.username = username
        user.email = user_email or None
        user.phone = user_phone or None
        user.save()
        return HttpResponse(status=200)


def clear_session(request, *args, **kwargs):
    logout(request)
    return HttpResponse(status=200)


def logout_view(request, *args, **kwargs):
    logout(request)

    redirect_to = request.GET.get('redirect_to')
    redirect_to_url_prefix = '{}://{}'.format(request.scheme, request.get_host())

    if redirect_to and is_safe_url(redirect_to, None):
        _parse = urllib.parse.urlparse(redirect_to)
        redirect_to = '{}{}'.format(redirect_to_url_prefix, _parse.path)
        if _parse.query:
            redirect_to += '?{}'.format(_parse.query)
    else:
        redirect_to = redirect_to_url_prefix

    sso_url_parse = urllib.parse.urlparse(sso_settings.IDP_API_ENDPOINT)
    sso_logout_url = '{}://{}/logout?{}'.format(
        sso_url_parse.scheme,
        sso_url_parse.netloc,
        urllib.parse.urlencode({'redirect_to': redirect_to}))
    return HttpResponseRedirect(sso_logout_url)