from django.contrib.auth.models import User
from django.db import models


class ChatMessage(models.Model):
    user = models.ForeignKey(
        User,
        on_delete=models.CASCADE,
        related_name="support_chats",
        limit_choices_to={"is_staff": False},
    )  # The requester (non-admin)
    sender = models.ForeignKey(
        User, on_delete=models.CASCADE, related_name="sent_messages"
    )  # The sender (user or admin)

    content = models.TextField()
    timestamp = models.DateTimeField(auto_now_add=True)

    @classmethod
    def get_support_chat(cls, user):
        return cls.objects.filter(user=user).order_by("timestamp")

    @classmethod
    def get_all_user_senders(cls):
        user_ids = cls.objects.values_list("user", flat=True).distinct()
        return User.objects.filter(id__in=user_ids, is_staff=False)