from django.contrib.auth.models import Group, Permission, User
from django.db import models
from django.db.models.signals import post_delete, post_save
from django.dispatch import receiver
from django.urls import reverse
from django.utils.translation import ugettext_lazy as _

from cof.petits_cours_models import choices_length


# ---
# User management
# ---


class Profile(models.Model):
    STATUS_EXTE = "exterieur"
    STATUS_1A = "1A"
    STATUS_2A = "2A"
    STATUS_3A = "3A"
    STATUS_4A = "4A"
    STATUS_ARCHI = "archicube"
    STATUS_DOCTORANT = "doctorant"
    STATUS_CST = "CST"
    STATUS_PEI = "PEI"

    OCCUPATION_CHOICES = (
        (STATUS_EXTE, _("Extérieur")),
        (STATUS_1A, _("1A")),
        (STATUS_2A, _("2A")),
        (STATUS_3A, _("3A")),
        (STATUS_4A, _("4A")),
        (STATUS_ARCHI, _("Archicube")),
        (STATUS_DOCTORANT, _("Doctorant")),
        (STATUS_CST, _("CST")),
        (STATUS_PEI, _("PEI")),
    )

    user = models.OneToOneField(
        User,
        on_delete=models.CASCADE,
        related_name="profile",
        verbose_name=_("utilisateur"),
    )
    login_clipper = models.CharField(
        _("login clipper"),
        max_length=8,
        blank=True,
    )
    phone = models.CharField(_("téléphone"), max_length=20, blank=True)
    occupation = models.CharField(_("occupation"),
                                  default="1A",
                                  choices=OCCUPATION_CHOICES,
                                  max_length=choices_length(
                                      OCCUPATION_CHOICES))
    departement = models.CharField(_("département"), max_length=50,
                                   blank=True)
    comments = models.TextField(
        _("commentaires visibles par l'utilisateur"), blank=True
    )

    class Meta:
        verbose_name = _("profil")
        verbose_name_plural = _("profils")

    def __str__(self):
        return self.user.username


@receiver(post_save, sender=User)
def create_user_profile(sender, instance, created, **kwargs):
    if created:
        Profile.objects.get_or_create(user=instance)


@receiver(post_delete, sender=Profile)
def post_delete_user(sender, instance, *args, **kwargs):
    instance.user.delete()


class AssociationManager(models.Manager):
    def get_by_natural_key(self, name):
        return self.get(name=name)


class Association(models.Model):
    objects = AssociationManager()

    name = models.CharField(
        _("nom de l'association"),
        unique=True,
        max_length=30
    )
    staff_group = models.ForeignKey(
        Group,
        on_delete=models.PROTECT,
        related_name="staff_group_of",
        blank=True, null=True,
        verbose_name=_("groupe des membres du bureau"),
    )
    members_group = models.ForeignKey(
        Group,
        on_delete=models.PROTECT,
        related_name="member_group_of",
        blank=True, null=True,
        verbose_name=_("groupe des membres"),
    )

    def natural_key(self):
        return [self.name]

    class Meta:
        verbose_name = _("association")
        verbose_name_plural = _("associations")

    def __str__(self):
        return self.name

    def setup_perms(self, buro_of_apps=[], perms=[]):
        """
        Setup permissions of the staff and members groups.

        Permission '<assoc_label>.member' is added to the 'members_group' of
        the association.

        Permission '<assoc_label>.buro' is added to the 'staff_group' of the
        association. All permissions of applications from 'buro_of_apps' are
        also added to this group.

        Arguments
            buro_of_apps (list of 'app_label', optional)
            perms (list of permission codes, optional)

        Should be used in receiver of 'post_migrate' signal, after permissions
        creation.

        """
        def try_add_perm(group, app_label, codename):
            try:
                perm = Permission.objects.get(
                    content_type__app_label=app_label,
                    codename=codename,
                )
            except Permission.DoesNotExist:
                pass
            else:
                group.permissions.add(perm)

        assoc_app_label = self.name.lower()

        # Buro group has perm '<assoc>.buro'.
        try_add_perm(self.staff_group, assoc_app_label, 'buro')

        # Add all permissions of applications given 'buro_of_apps'.
        apps_perms = Permission.objects.filter(
            content_type__app_label__in=buro_of_apps,
        )
        self.staff_group.permissions.add(*apps_perms)

        # Add extra permissions from 'perms'
        for perm in perms:
            app_label, codename = perm.split('.', maxsplit=1)
            try_add_perm(self.staff_group, app_label, codename)

        # Members have perm '<assoc>.member'.
        try_add_perm(self.members_group, assoc_app_label, 'member')


# ---
# Clubs
# ---

class Club(models.Model):
    ANNUAL = "ANN"
    SEMESTER = "SEM"
    COURSE = "COU"

    COTISATION_FREQUENCY_CHOICES = [
        (ANNUAL, _("Annuel")),
        (SEMESTER, _("Semestriel")),
        (COURSE, _("Au cours"))
    ]

    association = models.ForeignKey(
        Association,
        on_delete=models.PROTECT,
        related_name="clubs",
        verbose_name=_("association"),
    )
    name = models.CharField(_("nom"), max_length=200, unique=True)
    description = models.TextField(_("description"), blank=True)
    members = models.ManyToManyField(
        User,
        through="ClubUser",
        related_name="in_clubs",
        blank=True,
        verbose_name=_("membres du club"),
    )
    price = models.DecimalField(
        _("cotisation (€)"),
        decimal_places=2,
        max_digits=5,
        blank=True,
        default=0
    )
    cotisation_frequency = models.CharField(
        _("fréquence de la cotisation"),
        default=ANNUAL,
        choices=COTISATION_FREQUENCY_CHOICES,
        max_length=3,
        blank=True
    )

    class Meta:
        verbose_name = _("club")
        verbose_name_plural = _("clubs")

    def __str__(self):
        template = (
            self.needs_cotiz and
            "%(name)s (%(price).2f€ / %(cotisation_frequency)s)" or
            "%(name)s"
        )
        return template % vars(self)

    def get_absolute_url(self):
        return reverse('gestion:club_detail', args=[str(self.pk)])

    @property
    def needs_cotiz(self):
        return bool(self.price)

    def is_respo(self, user):
        return self.clubuser_set.filter(user=user, is_respo=True).exists()


class ClubUser(models.Model):
    user = models.ForeignKey(User, on_delete=models.CASCADE)
    club = models.ForeignKey(Club, on_delete=models.CASCADE)
    is_respo = models.BooleanField(_("est responsable du club"))
    has_paid = models.BooleanField(_("a payé sa cotisation"))

    class Meta:
        verbose_name = _("inscription au club")
        verbose_name_plural = _("inscriptions aux clubs")


# ---
# Events
# ---

class Location(models.Model):
    name = models.CharField(_("nom du lieu"), max_length=200)

    class Meta:
        verbose_name = _("lieu")
        verbose_name_plural = _("lieux")

    def __str__(self):
        return self.name


class Event(models.Model):
    associations = models.ManyToManyField(
        Association,
        related_name="events",
        verbose_name=_("associations"),
    )
    title = models.CharField(_("titre"), max_length=200)
    location = models.ForeignKey(
        Location,
        blank=True, null=True,
        on_delete=models.PROTECT,
        verbose_name=_("lieux"),
    )
    start_date = models.DateTimeField(
        _("début de l'événement"),
        blank=True, null=True,
    )
    end_date = models.DateTimeField(
        _("fin de l'événement"),
        blank=True, null=True,
    )
    description = models.TextField(_("description"), blank=True)
    image = models.ImageField(
        _("image"),
        blank=True, null=True,
        upload_to="public/imgs/events/",
    )
    registration_open = models.NullBooleanField(
        _("les inscriptions sont ouvertes"),
        help_text=_("Indéfini signifie « l'inscription n'est pas requise »"),
        default=True,
    )
    old = models.BooleanField(_("archiver (événement fini)"), default=False)

    class Meta:
        verbose_name = _("événement")
        verbose_name_plural = _("événements")

    def __str__(self):
        title, location = self.title, self.location
        start = self.start_date.date()
        end = self.end_date.date()
        if not self.start_date.date():
            return "{} @ {}".format(title, location)
        elif start == end:
            return "{} @ {} ({})".format(title, location, start)
        else:
            return "{} @ {} ({} → {})".format(title, location, start, end)


class EventCommentField(models.Model):
    TEXT = "text"
    CHAR = "char"

    FIELD_TYPE = [
        (TEXT, _("Texte long")),
        (CHAR, _("Texte court")),
    ]

    event = models.ForeignKey(
        Event,
        on_delete=models.CASCADE,
        related_name="commentfields",
        verbose_name=_("événement"),
    )
    name = models.CharField(_("nom du champ"), max_length=200)
    fieldtype = models.CharField(
        _("type de champ"),
        max_length=10,
        choices=FIELD_TYPE, default=TEXT,
    )
    default = models.TextField(_("valeur par défaut"), blank=True)
    ordering = models.IntegerField(
        _("ordre des champs"),
        default=0,
        help_text=_(
            "plus petit en premier, ordre alphabétique sur le nom si "
            "ambiguïté"
        ),
    )

    class Meta:
        verbose_name = _("champ")
        verbose_name_plural = _("champs")

    def __str__(self):
        return self.name


class EventCommentValue(models.Model):
    commentfield = models.ForeignKey(
        EventCommentField,
        on_delete=models.CASCADE,
        related_name="values"
    )
    registration = models.ForeignKey(
        "EventRegistration",
        on_delete=models.CASCADE,
        related_name="comments"
    )
    content = models.TextField(_("contenu"), blank=True)

    class Meta:
        unique_together = ("commentfield", "registration")

    def __str__(self):
        return (
            _("Commentaire de %(field_name)s")
            % {"field_name": self.commentfield}
        )


class EventOption(models.Model):
    event = models.ForeignKey(
        Event,
        on_delete=models.CASCADE,
        related_name="options",
        verbose_name=_("événement"),
    )
    name = models.CharField(_("option"), max_length=200)
    multi_choices = models.BooleanField(_("choix multiples"), default=False)

    class Meta:
        verbose_name = _("option des événements")
        verbose_name_plural = _("options des événements")

    def __str__(self):
        return self.name


class EventOptionChoice(models.Model):
    event_option = models.ForeignKey(
        EventOption,
        on_delete=models.CASCADE,
        related_name="choices",
        verbose_name=_("événement"),
    )
    value = models.CharField("Valeur", max_length=200)

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

    def __str__(self):
        return self.value


class EventRegistration(models.Model):
    user = models.ForeignKey(
        User,
        on_delete=models.SET_NULL,
        null=True,
        verbose_name=_("utilisateur"),
    )
    event = models.ForeignKey(
        Event,
        on_delete=models.CASCADE,
        verbose_name=_("événement"),
    )
    options = models.ManyToManyField(
        EventOptionChoice,
        verbose_name=_("choix"),
    )
    filledcomments = models.ManyToManyField(
        EventCommentField,
        through=EventCommentValue,
        verbose_name=_("commentaires"),
    )
    paid = models.BooleanField(_("a payé"), default=False)

    class Meta:
        verbose_name = _("inscription")
        verbose_name_plural = _("inscriptions")
        unique_together = ("user", "event")

    def __str__(self):
        return (
            _("Inscription de %(user)s à %(event)s")
            % {"user": self.user, "event": self.event}
        )