from django.conf import settings
from django.db import models
from django.db.models import Q


class ListingClick(models.Model):
    """Server-side record of a public listing detail view with optional UTM / ad parameters."""

    class ListingType(models.TextChoices):
        EQUIPMENT = "equipment", "Equipment"
        ADVENTURE = "adventure", "Adventure"

    class TrafficType(models.TextChoices):
        ORGANIC = "organic", "Organic"
        MARKETING = "marketing", "Marketing"

    vendor = models.ForeignKey("accounts.VendorProfile", on_delete=models.CASCADE, related_name="listing_clicks")
    listing_type = models.CharField(max_length=16, choices=ListingType.choices)
    equipment_item = models.ForeignKey(
        "equipment.EquipmentItem",
        on_delete=models.CASCADE,
        null=True,
        blank=True,
        related_name="marketing_clicks",
    )
    adventure_offering = models.ForeignKey(
        "adventrues.AdventureOffering",
        on_delete=models.CASCADE,
        null=True,
        blank=True,
        related_name="marketing_clicks",
    )
    traffic_type = models.CharField(max_length=16, choices=TrafficType.choices)
    utm_source = models.CharField(max_length=255, blank=True)
    utm_medium = models.CharField(max_length=255, blank=True)
    utm_campaign = models.CharField(max_length=255, blank=True)
    utm_term = models.CharField(max_length=255, blank=True)
    utm_content = models.CharField(max_length=255, blank=True)
    gclid = models.CharField(max_length=255, blank=True)
    fbclid = models.CharField(max_length=255, blank=True)
    referrer = models.TextField(blank=True)
    user = models.ForeignKey(
        settings.AUTH_USER_MODEL,
        on_delete=models.SET_NULL,
        null=True,
        blank=True,
        related_name="listing_clicks",
    )
    created_at = models.DateTimeField(auto_now_add=True)

    class Meta:
        ordering = ("-created_at",)
        indexes = [
            models.Index(fields=["vendor", "created_at"]),
            models.Index(fields=["vendor", "traffic_type", "created_at"]),
            models.Index(fields=["utm_campaign", "created_at"]),
        ]
        constraints = [
            models.CheckConstraint(
                condition=Q(listing_type="equipment", equipment_item__isnull=False, adventure_offering__isnull=True)
                | Q(listing_type="adventure", equipment_item__isnull=True, adventure_offering__isnull=False),
                name="listing_click_exactly_one_listing",
            ),
        ]

    def __str__(self) -> str:
        return f"ListingClick #{self.pk} ({self.listing_type}, {self.traffic_type})"