"""Tree — the top-level tenant boundary for genealogical data — and
TreeMembership, the basis for authorization (ARCHITECTURE §5).
"""

import uuid

from sqlalchemy import Enum as SAEnum
from sqlalchemy import ForeignKey, String, Text, UniqueConstraint
from sqlalchemy.orm import Mapped, mapped_column

from app.models.base import Base
from app.models.enums import MembershipRole, TreeVisibility
from app.models.mixins import SoftDelete, Timestamps, UUIDPrimaryKey


class Tree(Base, UUIDPrimaryKey, Timestamps, SoftDelete):
    __tablename__ = "trees"

    owner_id: Mapped[uuid.UUID] = mapped_column(
        ForeignKey("users.id", ondelete="RESTRICT"), index=True
    )
    name: Mapped[str] = mapped_column(String(255))
    description: Mapped[str | None] = mapped_column(Text)
    visibility: Mapped[TreeVisibility] = mapped_column(
        SAEnum(TreeVisibility, name="tree_visibility"),
        default=TreeVisibility.private,
        server_default=TreeVisibility.private.value,
    )
    # The person a tree opens focused on (its "home"/root person). Cleared if
    # that person is deleted. use_alter + name: trees<->persons form an FK cycle.
    home_person_id: Mapped[uuid.UUID | None] = mapped_column(
        ForeignKey(
            "persons.id",
            ondelete="SET NULL",
            name="fk_trees_home_person_id",
            use_alter=True,
        )
    )


class TreeMembership(Base, UUIDPrimaryKey, Timestamps):
    __tablename__ = "tree_memberships"
    __table_args__ = (
        UniqueConstraint("tree_id", "user_id", name="uq_tree_memberships_tree_user"),
    )

    tree_id: Mapped[uuid.UUID] = mapped_column(
        ForeignKey("trees.id", ondelete="CASCADE"), index=True
    )
    user_id: Mapped[uuid.UUID] = mapped_column(
        ForeignKey("users.id", ondelete="CASCADE"), index=True
    )
    role: Mapped[MembershipRole] = mapped_column(SAEnum(MembershipRole, name="membership_role"))