import uuid
from enum import Enum

from django.db import models
from django_extensions.db.models import TimeStampedModel

from vbv_lernwelt.core.models import Organisation, User
from vbv_lernwelt.course.models import CourseSessionUser


class LearningMentor(models.Model):
    mentor = models.ForeignKey(User, on_delete=models.CASCADE)
    course_session = models.ForeignKey("course.CourseSession", on_delete=models.CASCADE)

    participants = models.ManyToManyField(
        CourseSessionUser,
        related_name="participants",
        blank=True,
    )

    class Meta:
        unique_together = [["mentor", "course_session"]]
        verbose_name = "Lernbegleiter"
        verbose_name_plural = "Lernbegleiter"

    def __str__(self):
        return f"{self.mentor} ({self.course_session.title})"

    @property
    def course_sessions(self):
        return self.participants.values_list("course_session", flat=True).distinct()


class AgentParticipantRoleType(Enum):
    LEARNING_MENTOR = "LEARNING_MENTOR"  # Lernbegleiter
    BERUFSBILDNER = "BERUFSBILDNER"  # Lernbegleiter


class AgentParticipantRelation(models.Model):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)

    agent = models.ForeignKey(User, on_delete=models.CASCADE)
    participant = models.ForeignKey(CourseSessionUser, on_delete=models.CASCADE)

    role = models.CharField(
        max_length=255,
        choices=[(t.value, t.value) for t in AgentParticipantRoleType],
        default=AgentParticipantRoleType.LEARNING_MENTOR.value,
    )

    class Meta:
        unique_together = [("agent", "participant")]


class MentorInvitation(TimeStampedModel):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    email = models.EmailField()
    participant = models.ForeignKey(CourseSessionUser, on_delete=models.CASCADE)
    target_url = models.CharField(max_length=255, blank=True, default="")

    def __str__(self):
        return f"{self.email} ({self.participant})"

    class Meta:
        verbose_name = "Lernbegleiter Einladung"
        verbose_name_plural = "Lernbegleiter Einladungen"
        unique_together = [["email", "participant"]]


class OrganisationSupervisortRoleType(Enum):
    AUSBILDUNGSVERANTWORTLICHER = "AUSBILDUNGSVERANTWORTLICHER"
    BERUFSBILDNER = "BERUFSBILDNER"


class OrganisationSupervisor(models.Model):
    supervisor = models.ForeignKey(User, on_delete=models.CASCADE)
    organisation = models.ForeignKey(Organisation, on_delete=models.CASCADE)

    role = models.CharField(
        max_length=255,
        choices=[(t.value, t.value) for t in OrganisationSupervisortRoleType],
        default=OrganisationSupervisortRoleType.AUSBILDUNGSVERANTWORTLICHER.value,
    )

    def save(self, *args, **kwargs):
        if (
            self.role
            == OrganisationSupervisortRoleType.AUSBILDUNGSVERANTWORTLICHER.value
        ):
            from vbv_lernwelt.learning_mentor.services import (
                create_or_sync_ausbildungsverantwortlicher,
            )

            create_or_sync_ausbildungsverantwortlicher(
                self.supervisor, self.organisation
            )
        elif self.role == OrganisationSupervisortRoleType.BERUFSBILDNER.value:
            from vbv_lernwelt.learning_mentor.services import (
                create_or_sync_berufsbildner,
            )

            create_or_sync_berufsbildner(self.supervisor, self.organisation)
        super().save(*args, **kwargs)