from django.db import models
from django.conf import settings
from django.contrib.contenttypes.fields import GenericForeignKey
from django.contrib.contenttypes.models import ContentType
from apps.core.history import TrackedModel
import pghistory

@pghistory.track()
class Review(TrackedModel):
    user = models.ForeignKey(
        settings.AUTH_USER_MODEL,
        on_delete=models.CASCADE,
        related_name="reviews",
        help_text="User who wrote the review",
    )
    
    # Generic relation to target object (Park, Ride, etc.)
    content_type = models.ForeignKey(
        ContentType,
        on_delete=models.CASCADE,
        help_text="Type of item being reviewed",
    )
    object_id = models.PositiveIntegerField(help_text="ID of the item being reviewed")
    content_object = GenericForeignKey("content_type", "object_id")

    # Review content
    rating = models.PositiveSmallIntegerField(
        choices=[(i, str(i)) for i in range(1, 6)],
        help_text="Rating from 1 to 5",
        db_index=True,
    )
    text = models.TextField(blank=True, help_text="Review text (optional)")
    
    # Metadata
    is_public = models.BooleanField(
        default=True, 
        help_text="Whether this review is visible to others"
    )
    helpful_votes = models.PositiveIntegerField(
        default=0, 
        help_text="Number of users who found this helpful"
    )

    class Meta(TrackedModel.Meta):
        verbose_name = "Review"
        verbose_name_plural = "Reviews"
        ordering = ["-created_at"]
        # Ensure one review per user per object
        unique_together = [["user", "content_type", "object_id"]]
        indexes = [
            models.Index(fields=["content_type", "object_id"]),
            models.Index(fields=["rating"]),
        ]

    def __str__(self):
        return f"{self.user.username}'s {self.rating}-star review on {self.content_object}"