# -*- coding: utf-8 -*-

from __future__ import division

__copyright__ = "Copyright (C) 2016 Dong Zhuang, Andreas Kloeckner"

__license__ = """
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
"""

from django.db.models.signals import post_save
from django.dispatch import receiver
from accounts.models import User

@receiver(post_save, sender=User)
def update_enrollment_status(sender, created, instance, **kwargs):
    if not created:
        user = instance
        from course.models import (
                Participation, participation_status,
                ParticipationPreapproval,
                )

        requested_qset = Participation.objects.filter(
                user=user, status=participation_status.requested)
        if requested_qset is None:
            pass

        for requested in requested_qset:
            course = requested.course

            preapproval = None
            if user.email:
                try:
                    preapproval = ParticipationPreapproval.objects.get(
                            course=course, email__iexact=user.email)
                except ParticipationPreapproval.DoesNotExist:
                    if user.institutional_id:
                        if not (course.preapproval_require_verified_inst_id
                                and not user.institutional_id_verified):
                            try:
                                preapproval = (
                                     ParticipationPreapproval.objects.get(
                                         course=course,
                                         institutional_id__iexact\
                                                 =user.institutional_id))
                            except ParticipationPreapproval.DoesNotExist:
                                pass
                pass

            def enroll(status, role):
                participations = Participation.objects.filter(
                        course=course, user=user)

                assert participations.count() <= 1
                if participations.count() == 0:
                    participation = Participation()
                    participation.user = user
                    participation.course = course
                    participation.role = role
                    participation.status = status
                    participation.save()
                else:
                    (participation,) = participations
                    participation.status = status
                    participation.save()

                return participation

            if preapproval is not None:
                role = preapproval.role
                enroll(participation_status.active, role)

                from course.enrollment import send_enrollment_decision
                send_enrollment_decision(requested, True)

# vim: foldmethod=marker