#tenancy/models.py

import datetime
from django.conf import settings
from django.db import models
from django.utils.text import slugify

class Tenant(models.Model):
    class Status(models.TextChoices):
        ACTIVE = "active", "Active"
        SUSPENDED = "suspended", "Suspended"

    # 1) Identité
    name = models.CharField(max_length=200, unique=True)
    slug = models.SlugField(max_length=220, unique=True, blank=True)
    legal_name = models.CharField(max_length=255, blank=True, null=True)  # raison sociale
    industry = models.CharField(max_length=120, blank=True, null=True)    # secteur

    # 2) Contact
    contact_name = models.CharField(max_length=120, blank=True, null=True)
    email = models.EmailField(blank=True, null=True)
    phone = models.CharField(max_length=40, blank=True, null=True)
    website = models.URLField(blank=True, null=True)

    # 3) Localisation / positionnement
    country = models.CharField(max_length=2, blank=True, null=True)  # ISO2: TD, FR...
    city = models.CharField(max_length=120, blank=True, null=True)
    address_line1 = models.CharField(max_length=255, blank=True, null=True)
    address_line2 = models.CharField(max_length=255, blank=True, null=True)
    postal_code = models.CharField(max_length=30, blank=True, null=True)

    # 4) Paramètres “monde”
    timezone = models.CharField(max_length=64, blank=True, null=True)  # ex: Africa/Ndjamena
    locale = models.CharField(max_length=10, blank=True, null=True)    # ex: fr, en
    currency = models.CharField(max_length=3, blank=True, null=True)   # ex: XAF

    # 5) SaaS
    status = models.CharField(max_length=12, choices=Status.choices, default=Status.ACTIVE)
    plan = models.CharField(max_length=50, blank=True, null=True)
    trial_ends_at = models.DateTimeField(blank=True, null=True)

    # 6) Conformité / Identifiants (optionnel)
    tax_id = models.CharField(max_length=80, blank=True, null=True)
    registration_id = models.CharField(max_length=80, blank=True, null=True)

    # 7) Branding
    logo = models.ImageField(upload_to="tenants/logos/", blank=True, null=True)

    # 8) Extensible
    metadata = models.JSONField(blank=True, null=True)

    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)

    def save(self, *args, **kwargs):
        if not self.slug:
            base = slugify(self.name)
            slug = base
            i = 2
            while Tenant.objects.filter(slug=slug).exists():
                slug = f"{base}-{i}"
                i += 1
            self.slug = slug
        super().save(*args, **kwargs)

    def __str__(self):
        return self.name


class TenantLicense(models.Model):
    """Licence d'abonnement associée à un tenant (1-to-1)."""

    class Plan(models.TextChoices):
        ANNUAL   = "annual",   "Annuel"
        LIFETIME = "lifetime", "À vie"

    tenant = models.OneToOneField(
        Tenant, on_delete=models.CASCADE, related_name="license"
    )
    plan       = models.CharField(max_length=20, choices=Plan.choices, default=Plan.ANNUAL)
    starts_at  = models.DateField()
    expires_at = models.DateField(null=True, blank=True)  # null = à vie
    is_active  = models.BooleanField(default=True)
    notes      = models.TextField(blank=True, default="")
    created_by = models.ForeignKey(
        settings.AUTH_USER_MODEL, on_delete=models.SET_NULL,
        null=True, blank=True, related_name="created_licenses",
    )
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)

    # ── propriétés calculées ────────────────────────────────────────────────

    @property
    def is_expired(self) -> bool:
        if not self.is_active:
            return True
        if self.plan == self.Plan.LIFETIME:
            return False
        if self.expires_at is None:
            return False
        return datetime.date.today() > self.expires_at

    @property
    def days_remaining(self) -> int | None:
        if self.plan == self.Plan.LIFETIME or not self.expires_at:
            return None
        delta = (self.expires_at - datetime.date.today()).days
        return max(0, delta)

    def __str__(self):
        end = self.expires_at.isoformat() if self.expires_at else "jamais"
        return f"{self.tenant.name} — {self.get_plan_display()} (expire {end})"

    class Meta:
        verbose_name = "Licence tenant"
        verbose_name_plural = "Licences tenant"