from django.contrib.contenttypes.fields import GenericForeignKey
from django.contrib.contenttypes.models import ContentType
from django.db import models
from django.utils.translation import gettext_lazy as _

from common.utils import lazyproperty
from orgs.mixins.models import JMSOrgBaseModel


class Label(JMSOrgBaseModel):
    name = models.CharField(max_length=64, verbose_name=_("Name"), db_index=True)
    value = models.CharField(max_length=64, unique=False, verbose_name=_("Value"))
    internal = models.BooleanField(default=False, verbose_name=_("Internal"))

    class Meta:
        unique_together = [("name", "value", "org_id")]
        verbose_name = _("Tag")

    @lazyproperty
    def res_count(self):
        return self.labeled_resources.count()

    @lazyproperty
    def display_name(self):
        return "{}:{}".format(self.name, self.value)

    def __str__(self):
        return "{}:{}".format(self.name, self.value)


class LabeledResource(JMSOrgBaseModel):
    label = models.ForeignKey(
        Label,
        on_delete=models.CASCADE,
        related_name="labeled_resources",
        verbose_name=_("Tag"),
    )
    res_type = models.ForeignKey(ContentType, on_delete=models.CASCADE)
    res_id = models.CharField(
        max_length=36, verbose_name=_("Resource ID"), db_index=True
    )
    resource = GenericForeignKey("res_type", "res_id")

    class Meta:
        unique_together = [("label", "res_type", "res_id", "org_id")]
        verbose_name = _("Tagged resource")

    def __str__(self):
        return "{} => {}".format(self.label, self.resource)