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

from .models import Grade, Lesson, Node, Unit, UserAnswer, UserLessonCompletion
from .services import touch_node_progress_on_answer, update_node_progress_on_lesson_completion


@receiver(post_save, sender=UserAnswer, dispatch_uid='content_touch_node_progress_on_answer')
def _on_user_answer_created(sender, instance, created, **kwargs):
    if not created:
        return
    touch_node_progress_on_answer(instance.user_id, instance.question)


@receiver(post_save, sender=UserLessonCompletion, dispatch_uid='content_update_node_progress_on_completion')
def _on_lesson_completion_created(sender, instance, created, **kwargs):
    if not created:
        return
    update_node_progress_on_lesson_completion(instance.user_id, instance.lesson)


# با هر تغییرِ برنامه‌ی درسی (از ادمین یا seed)، نسخه‌ی کشِ محتوا یک واحد جلو
# می‌رود و همه‌ی کلیدهای content:grades / content:tree را یک‌جا باطل می‌کند.
@receiver(post_save, sender=Grade, dispatch_uid='content_bump_curriculum_grade_save')
@receiver(post_delete, sender=Grade, dispatch_uid='content_bump_curriculum_grade_delete')
@receiver(post_save, sender=Unit, dispatch_uid='content_bump_curriculum_unit_save')
@receiver(post_delete, sender=Unit, dispatch_uid='content_bump_curriculum_unit_delete')
@receiver(post_save, sender=Node, dispatch_uid='content_bump_curriculum_node_save')
@receiver(post_delete, sender=Node, dispatch_uid='content_bump_curriculum_node_delete')
@receiver(post_save, sender=Lesson, dispatch_uid='content_bump_curriculum_lesson_save')
@receiver(post_delete, sender=Lesson, dispatch_uid='content_bump_curriculum_lesson_delete')
def _bump_curriculum_cache_version(sender, **kwargs):
    from .views import bump_curriculum_version
    bump_curriculum_version()