import enum
import uuid

from sqlalchemy import Enum, ForeignKey, String, Text
from sqlalchemy.dialects.postgresql import UUID
from sqlalchemy.orm import Mapped, mapped_column, relationship

from api.models.base import Base, TimestampMixin, new_uuid


class TopicStatus(str, enum.Enum):
    active = "active"
    paused = "paused"
    archived = "archived"


class Topic(Base, TimestampMixin):
    __tablename__ = "topics"

    id: Mapped[uuid.UUID] = mapped_column(
        UUID(as_uuid=True), primary_key=True, default=new_uuid
    )
    slug: Mapped[str] = mapped_column(String(100), unique=True, nullable=False, index=True)
    title: Mapped[str] = mapped_column(String(255), nullable=False)
    description: Mapped[str | None] = mapped_column(Text, nullable=True)
    domain_id: Mapped[uuid.UUID] = mapped_column(
        UUID(as_uuid=True),
        ForeignKey("domains.id", ondelete="RESTRICT"),
        nullable=False,
        index=True,
    )
    status: Mapped[TopicStatus] = mapped_column(
        Enum(TopicStatus), nullable=False, default=TopicStatus.active
    )

    domain: Mapped["Domain"] = relationship(  # noqa: F821
        "Domain", back_populates="topics", lazy="selectin"
    )
    workstreams: Mapped[list["Workstream"]] = relationship(  # noqa: F821
        "Workstream", back_populates="topic", lazy="selectin"
    )
    decisions: Mapped[list["Decision"]] = relationship(  # noqa: F821
        "Decision", back_populates="topic", lazy="selectin"
    )
    progress_events: Mapped[list["ProgressEvent"]] = relationship(  # noqa: F821
        "ProgressEvent", back_populates="topic", lazy="selectin"
    )

    @property
    def domain_slug(self) -> str | None:
        """Returns the domain slug string for serialization."""
        if self.domain is not None:
            return self.domain.slug
        return None