import json

from django.dispatch import receiver
from django.db.models.signals import post_save, post_delete

from config.models import Stream, Pull
from config.signals_shared import stream_active, stream_inactive, pull_active, pull_inactive
from concierge.models import Task

@receiver(pull_active)
def create_pull_tasks_on_activate(sender, **kwargs):
    pull = Pull.objects.get(id=kwargs['pull_id'])
    Task.objects.get_or_create(stream=pull.stream, type='pull', config_id=pull.id,
        configuration=json.dumps(pull.get_concierge_configuration()))


@receiver(pull_inactive)
def delete_pull_tasks_on_inactivate(sender, **kwargs):
    pull = Pull.objects.get(id=kwargs['pull_id'])
    Task.objects.filter(type='pull', config_id=pull.id).delete()


@receiver(post_save, sender=Pull)
def update_pull_tasks(sender, **kwargs):
    instance = kwargs['instance']

    try:
        task = Task.objects.filter(type='pull', config_id=instance.id).get()
        task.delete()
    except Task.DoesNotExist:
        pass

    if instance.active:
        task = Task(stream=instance.stream, type='pull', config_id=instance.id,
                    configuration=json.dumps(instance.get_concierge_configuration()))
        task.save()

@receiver(post_delete, sender=Pull)
def delete_pull_tasks(sender, **kwargs):
    instance = kwargs['instance']
    # Get the current task instance if it exists, and remove it
    try:
        task = Task.objects.filter(type='pull', config_id=instance.id).get()
        task.delete()
    except Task.DoesNotExist:
        pass