from django.conf import settings
from django.db import models
from django.utils.translation import gettext_lazy as _
from django.utils.translation import get_language


class MapConfig(models.Model):
    """
    Defines access permissions for a named map.

    Three access levels are supported:
    - ``public``: no login required, accessible by anyone.
    - ``authenticated``: any logged-in user can access.
    - ``restricted``: access is granted when at least one of the
      thematic / team / user conditions is satisfied (OR logic).
      Admins always bypass this check.
    """

    ACCESS_PUBLIC = 'public'
    ACCESS_AUTHENTICATED = 'authenticated'
    ACCESS_RESTRICTED = 'restricted'

    ACCESS_LEVEL_CHOICES = [
        (ACCESS_PUBLIC, _('Tout public (sans connexion)')),
        (ACCESS_AUTHENTICATED, _('Toute personne connectée')),
        (ACCESS_RESTRICTED, _('Accès restreint (thématiques / équipes / utilisateurs)')),
    ]

    code = models.CharField(
        max_length=100,
        unique=True,
        verbose_name=_("Code"),
        help_text=_("Identifiant technique de la carte (ex: concrete_blocks)."),
    )
    name_fr = models.CharField(max_length=200, verbose_name=_("Nom (FR)"))
    name_nl = models.CharField(max_length=200, blank=True, verbose_name=_("Naam (NL)"))

    access_level = models.CharField(
        max_length=20,
        choices=ACCESS_LEVEL_CHOICES,
        default=ACCESS_AUTHENTICATED,
        verbose_name=_("Niveau d'accès"),
    )

    # ── Restricted access grants ─────────────────────────────────────────────

    thematics = models.ManyToManyField(
        'common.Thematic',
        blank=True,
        related_name='map_configs',
        verbose_name=_("Thématiques autorisées"),
        help_text=_(
            "Les utilisateurs ayant accès à l'une de ces thématiques "
            "peuvent visualiser la carte (niveau 'restreint' uniquement)."
        ),
    )

    teams = models.ManyToManyField(
        'contracts.CompanyTeam',
        blank=True,
        related_name='map_configs',
        verbose_name=_("Équipes autorisées"),
        help_text=_(
            "Les membres de ces équipes peuvent visualiser la carte "
            "(niveau 'restreint' uniquement)."
        ),
    )

    users = models.ManyToManyField(
        settings.AUTH_USER_MODEL,
        blank=True,
        related_name='map_configs',
        verbose_name=_("Utilisateurs autorisés"),
        help_text=_(
            "Ces utilisateurs spécifiques peuvent visualiser la carte "
            "(niveau 'restreint' uniquement)."
        ),
    )

    # ─────────────────────────────────────────────────────────────────────────

    class Meta:
        verbose_name = _("Configuration d'accès à une carte")
        verbose_name_plural = _("Configurations d'accès aux cartes")
        ordering = ['code']

    @property
    def name(self):
        lang = get_language()
        if lang and lang.startswith('nl') and self.name_nl:
            return self.name_nl
        return self.name_fr

    def __str__(self):
        return f"{self.name_fr} ({self.code})"