"""
Group Model

Represents groups synced from Authentik.
Groups are used for access control and user organization.
"""
import uuid
from datetime import datetime
from typing import TYPE_CHECKING, List

from sqlalchemy import String, Boolean, DateTime, func, Table, Column, ForeignKey
from sqlalchemy.dialects.postgresql import UUID
from sqlalchemy.orm import Mapped, mapped_column, relationship

from src.db.database import Base


# Association table for User-Group many-to-many relationship
user_groups = Table(
    "user_groups",
    Base.metadata,
    Column("user_id", UUID(as_uuid=True), ForeignKey("users.id", ondelete="CASCADE"), primary_key=True),
    Column("group_id", UUID(as_uuid=True), ForeignKey("groups.id", ondelete="CASCADE"), primary_key=True),
)


class Group(Base):
    """
    Group model synced from Authentik

    Groups are fetched from Authentik admin API and cached locally.
    They represent organizational units for access control.
    """

    __tablename__ = "groups"

    id: Mapped[uuid.UUID] = mapped_column(
        UUID(as_uuid=True),
        primary_key=True,
        default=uuid.uuid4,
    )
    authentik_id: Mapped[uuid.UUID] = mapped_column(
        UUID(as_uuid=True),
        unique=True,
        nullable=False,
        index=True,
        comment="Authentik group UUID",
    )
    name: Mapped[str] = mapped_column(
        String(255),
        unique=True,
        nullable=False,
        index=True,
    )
    is_superuser: Mapped[bool] = mapped_column(
        Boolean,
        default=False,
        nullable=False,
        comment="Whether members of this group have superuser privileges",
    )
    parent_name: Mapped[str | None] = mapped_column(
        String(255),
        nullable=True,
        comment="Parent group name for hierarchy",
    )
    member_count: Mapped[int] = mapped_column(
        default=0,
        nullable=False,
        comment="Number of users in this group",
    )
    created_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True),
        server_default=func.now(),
        nullable=False,
    )
    synced_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True),
        server_default=func.now(),
        onupdate=func.now(),
        nullable=False,
        comment="Last sync from Authentik",
    )

    def __repr__(self) -> str:
        return f"<Group {self.name}>"