from __future__ import annotations

from django.core.exceptions import ValidationError
from django.db import models


class Comment(models.Model):
    article = models.ForeignKey("blog.ArticlePage", on_delete=models.CASCADE, related_name="comments")
    parent = models.ForeignKey("self", null=True, blank=True, on_delete=models.CASCADE, related_name="replies")
    author_name = models.CharField(max_length=100)
    author_email = models.EmailField()
    body = models.TextField(max_length=2000)
    is_approved = models.BooleanField(default=False)
    created_at = models.DateTimeField(auto_now_add=True)
    ip_address = models.GenericIPAddressField(null=True, blank=True)

    def clean(self) -> None:
        if self.parent and self.parent.parent_id is not None:
            raise ValidationError("Replies cannot be nested beyond one level.")

    def get_absolute_url(self):
        return f"{self.article.url}#comment-{self.pk}"

    def __str__(self) -> str:
        return f"Comment by {self.author_name}"


class CommentReaction(models.Model):
    comment = models.ForeignKey(Comment, on_delete=models.CASCADE, related_name="reactions")
    reaction_type = models.CharField(max_length=20, choices=[("heart", "❤️"), ("plus_one", "👍")])
    session_key = models.CharField(max_length=64)
    created_at = models.DateTimeField(auto_now_add=True)

    class Meta:
        constraints = [
            models.UniqueConstraint(
                fields=["comment", "reaction_type", "session_key"],
                name="unique_comment_reaction_per_session",
            )
        ]

    def __str__(self) -> str:
        return f"{self.reaction_type} on comment {self.comment_id}"