from django.db import models


class DashboardCardSnapshot(models.Model):
    sensor_id = models.UUIDField(db_index=True)
    card_name = models.CharField(max_length=128, db_index=True)
    payload = models.JSONField(default=dict, blank=True)
    generated_at = models.DateTimeField(auto_now_add=True, db_index=True)
    expires_at = models.DateTimeField(db_index=True)
    source = models.CharField(max_length=32, default="computed")

    class Meta:
        ordering = ["-generated_at"]
        indexes = [
            models.Index(fields=["sensor_id", "card_name", "-generated_at"]),
        ]
        verbose_name = "Dashboard Card Snapshot"
        verbose_name_plural = "Dashboard Card Snapshots"

    def __str__(self):
        return f"{self.card_name} - {self.sensor_id} - {self.generated_at}"


class DashboardAiRequestLog(models.Model):
    sensor_id = models.UUIDField(db_index=True)
    request_payload = models.JSONField(default=dict, blank=True)
    response_payload = models.JSONField(default=dict, blank=True)
    status = models.CharField(max_length=32, default="pending")
    created_at = models.DateTimeField(auto_now_add=True, db_index=True)

    class Meta:
        ordering = ["-created_at"]
        verbose_name = "Dashboard AI Request Log"
        verbose_name_plural = "Dashboard AI Request Logs"

    def __str__(self):
        return f"{self.sensor_id} - {self.status} - {self.created_at}"


class NdviObservation(models.Model):
    location = models.ForeignKey(
        "location_data.SoilLocation",
        on_delete=models.CASCADE,
        related_name="ndvi_observations",
    )
    observation_date = models.DateField(db_index=True)
    mean_ndvi = models.FloatField()
    ndvi_map = models.JSONField(default=dict, blank=True)
    vegetation_health_class = models.CharField(max_length=64)
    satellite_source = models.CharField(max_length=64, default="sentinel-2")
    cloud_cover = models.FloatField(null=True, blank=True)
    metadata = models.JSONField(default=dict, blank=True)
    created_at = models.DateTimeField(auto_now_add=True, db_index=True)

    class Meta:
        ordering = ["-observation_date", "-created_at"]
        constraints = [
            models.UniqueConstraint(
                fields=["location", "observation_date", "satellite_source"],
                name="ndvi_unique_location_date_source",
            )
        ]
        verbose_name = "NDVI Observation"
        verbose_name_plural = "NDVI Observations"

    def __str__(self):
        return f"NDVI {self.location_id} {self.observation_date} {self.satellite_source}"