from django.conf import settings
from django.db import models


class Note(models.Model):
    class Kind(models.TextChoices):
        TASK = 'task', 'Tâche'
        INFO = 'info', 'Information'
        MEMO = 'memo', 'Mémo'
        SUGGESTION = 'sugg', 'Suggestion'

    title = models.CharField(
        max_length=160,
    )

    content = models.TextField(
        blank=True,
        max_length=5000,
    )

    kind = models.CharField(
        max_length=4,
        choices=Kind.choices,
        default=Kind.MEMO,
    )

    author = models.ForeignKey(
        settings.AUTH_USER_MODEL,
        on_delete=models.SET_NULL,
        null=True,
        related_name='authored_notes',
    )

    recipients = models.ManyToManyField(
        settings.AUTH_USER_MODEL,
        blank=True,
        related_name='addressed_notes',
    )

    is_public = models.BooleanField(
        default=True,
    )

    completed_at = models.DateTimeField(
        null=True,
        blank=True,
    )

    created_at = models.DateTimeField(
        auto_now_add=True,
    )

    updated_at = models.DateTimeField(
        auto_now=True,
    )

    class Meta:
        ordering = [
            '-created_at',
            '-pk',
        ]

        constraints = [
            models.CheckConstraint(
                condition=(
                    models.Q(kind='task')
                    | models.Q(
                        completed_at__isnull=True,
                    )
                ),
                name='only_tasks_can_be_completed',
            ),
        ]

    @property
    def is_done(self):
        return self.completed_at is not None

    def __str__(self):
        return self.title