import uuid
from datetime import datetime

from sqlalchemy import BigInteger, CheckConstraint, ForeignKey, Text, func
from sqlalchemy.dialects.postgresql import UUID
from sqlalchemy.orm import Mapped, mapped_column

from app.db import Base


class Message(Base):
    __tablename__ = "messages"
    __table_args__ = (
        CheckConstraint("sender_type IN ('player', 'dm', 'system')", name="ck_message_sender_type"),
    )

    id: Mapped[int] = mapped_column(BigInteger, primary_key=True, autoincrement=True)
    game_id: Mapped[uuid.UUID] = mapped_column(
        UUID(as_uuid=True), ForeignKey("games.id", ondelete="CASCADE"), nullable=False, index=True
    )
    sender_type: Mapped[str] = mapped_column(Text, nullable=False)
    user_id: Mapped[uuid.UUID | None] = mapped_column(
        UUID(as_uuid=True), ForeignKey("users.id"), nullable=True
    )
    character_id: Mapped[uuid.UUID | None] = mapped_column(
        UUID(as_uuid=True), ForeignKey("characters.id"), nullable=True
    )
    content: Mapped[str] = mapped_column(Text, nullable=False)
    created_at: Mapped[datetime] = mapped_column(
        server_default=func.now(), nullable=False, index=True
    )