from django.db import models
from django.core.exceptions import ValidationError
from django.utils.translation import ugettext_lazy as _
from django.contrib.auth.models import Group
from event.models import Activity, EventSpecificMixin

from .fields import IdField

from taggit.managers import TaggableManager
from datetime import date


class EquipmentCategory(models.Model):
    name = models.CharField(
                _("nom"),
                max_length=200,
                )
    parent = models.ForeignKey(
                'self',
                blank=True,
                null=True,
                default=None,
                help_text=_("merci de ne pas faire de référence cyclique"),
                )

    class Meta:
        verbose_name = _("catégories")
        verbose_name_plural = _("catégories")

    def __str__(self):
        return self.name


class Equipment(EventSpecificMixin, models.Model):
    name = models.CharField(
                _("nom du matériel"),
                max_length=200,
            )
    stock = models.PositiveSmallIntegerField(_("quantité disponible"))
    description = models.TextField(_("description"))
    activities = models.ManyToManyField(
                Activity,
                related_name="equipment",
                through="EquipmentAttribution",
            )
    owner = models.ForeignKey(
            Group,
            blank=True,
            null=True,
            )
    category = models.ForeignKey(
            EquipmentCategory,
            on_delete=models.PROTECT,
            )

    class Meta:
        verbose_name = _("matériel")
        verbose_name_plural = _("matériels")

    def __str__(self):
        return self.name


class EquipmentAttribute(models.Model):
    name = models.CharField(
                _("nom"),
                max_length=200,
                unique=True,
                )

    class Meta:
        verbose_name = _("attribut")
        verbose_name_plural = _("attributs")

    def __str__(self):
        return self.name

class EquipmentAttributeValue(models.Model):
    equipment = models.ForeignKey(
                Equipment,
                on_delete=models.CASCADE,
                related_name="attributes",
                help_text=_("Matériel concerné par le defaut"),
            )
    attribute = models.ForeignKey(
                    EquipmentAttribute,
                    on_delete=models.CASCADE,
                    )
    value = models.CharField(
                    _("valeur"),
                    max_length=200,
                    )

    class Meta:
        verbose_name = _("attribut de matériel")
        verbose_name_plural = _("attributs de matériel")

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


class EquipmentAttribution(models.Model):
    equipment = models.ForeignKey(Equipment)
    activity = models.ForeignKey(Activity)
    amount = models.BigIntegerField(_("quantité attribuée"))
    remarks = models.TextField(_("remarques concernant l'attribution"))

    class Meta:
        verbose_name = _("attribution de matériel")
        verbose_name_plural = _("attributions de matériel")

    def __str__(self):
        return "%s (%d) -> %s" % (self.equipment.name,
                                  self.amout,
                                  self.activity.get_herited('title'))

    def save(self, *args, **kwargs):
        if self.equipment.event and self.equipment.event != self.activity.event:
            raise ValidationError

        super(EquipmentAttribution, self).save(*args, **kwargs)


class EquipmentDefault(models.Model):
    remark = models.TextField(_("remarque sur le défaut"))
    equipment = models.ForeignKey(
                Equipment,
                on_delete=models.CASCADE,
                related_name="remarks",
                help_text=_("Matériel concerné par le defaut"),
            )
    ids = IdField()
    is_unusable = models.BooleanField(_("inutilisable"))
    send_repare = models.BooleanField(_("à envoyer réparareur"))

    class Meta:
        verbose_name = _("defaut matériel")
        verbose_name_plural = _("défauts sur le matériel")

    def __str__(self):
        return "%s : %s" % (self.equipment.name,
                            self.remark)


class EquipmentLost(models.Model):
    lost_at = models.DateField(
            _("perdu le"),
            default=date.today,
            )
    equipment = models.ForeignKey(
                Equipment,
                on_delete=models.CASCADE,
                related_name="losts",
                help_text=_("Matériel concerné par la perte"),
            )
    ids = IdField()


class EquipmentRevision(models.Model):
    date = models.DateField(
            _("date"),
            default=date.today,
            )
    equipment = models.ForeignKey(
                Equipment,
                on_delete=models.CASCADE,
                related_name="revisions",
                help_text=_("Matériel concerné par les révisions"),
            )
    remark = models.TextField(_("remarque sur la révision"))
    ids = IdField()

    class Meta:
        verbose_name = _("révision de matériel")
        verbose_name_plural = _("révisions de matériel")

    def __str__(self):
        return "%s : %s" % (self.equipment.name,
                            self.remark)