"""SQLAlchemy identity and tenant metadata models."""

from __future__ import annotations

from datetime import datetime, timezone
from typing import List
from uuid import uuid4

from sqlalchemy import CheckConstraint, DateTime, Enum as SAEnum, ForeignKey, Integer, String, UniqueConstraint, func, text
from sqlalchemy.orm import Mapped, mapped_column, relationship

from ..db import Base
from ..security.policy import Role


def _id(prefix: str) -> str:
    return f"{prefix}_{uuid4().hex}"


def _utc_now() -> datetime:
    return datetime.now(timezone.utc)


def _role_values(enum_type):
    return [member.value for member in enum_type]


class Organization(Base):
    __tablename__ = "organizations"

    id: Mapped[str] = mapped_column(String(64), primary_key=True, default=lambda: _id("org"))
    name: Mapped[str] = mapped_column(String(160), nullable=False)
    slug: Mapped[str] = mapped_column(String(80), nullable=False, unique=True, index=True)
    status: Mapped[str] = mapped_column(
        String(32), nullable=False, default="active", server_default=text("'active'")
    )
    created_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True), default=_utc_now, server_default=func.now(), nullable=False
    )

    memberships: Mapped[List["Membership"]] = relationship(
        back_populates="organization", cascade="all, delete-orphan"
    )


class User(Base):
    __tablename__ = "users"

    id: Mapped[str] = mapped_column(String(64), primary_key=True, default=lambda: _id("usr"))
    email_normalized: Mapped[str] = mapped_column(String(320), nullable=False, unique=True, index=True)
    password_hash: Mapped[str] = mapped_column(
        String(512), nullable=False, default="!invite_pending", server_default=text("'!invite_pending'")
    )
    status: Mapped[str] = mapped_column(
        String(32), nullable=False, default="active", server_default=text("'active'")
    )
    auth_version: Mapped[int] = mapped_column(
        Integer, nullable=False, default=0, server_default=text("0")
    )
    locale: Mapped[str] = mapped_column(
        String(8), nullable=False, default="th", server_default=text("'th'")
    )
    created_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True), default=_utc_now, server_default=func.now(), nullable=False
    )
    last_login_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True), nullable=True)

    memberships: Mapped[List["Membership"]] = relationship(
        back_populates="user", cascade="all, delete-orphan"
    )
    sessions: Mapped[List["AuthSession"]] = relationship(
        back_populates="user", cascade="all, delete-orphan"
    )


class Membership(Base):
    __tablename__ = "memberships"
    __table_args__ = (
        UniqueConstraint("user_id", "organization_id", name="uq_membership_user_org"),
        CheckConstraint(
            "role IN ('super_admin', 'admin', 'user')",
            name="ck_membership_role",
        ),
    )

    id: Mapped[str] = mapped_column(String(64), primary_key=True, default=lambda: _id("mem"))
    user_id: Mapped[str] = mapped_column(
        ForeignKey("users.id", ondelete="CASCADE"), nullable=False, index=True
    )
    organization_id: Mapped[str] = mapped_column(
        ForeignKey("organizations.id", ondelete="CASCADE"), nullable=False, index=True
    )
    role: Mapped[Role] = mapped_column(
        SAEnum(
            Role,
            name="role",
            values_callable=_role_values,
            native_enum=False,
            create_constraint=False,
            validate_strings=True,
        ),
        nullable=False,
    )
    status: Mapped[str] = mapped_column(
        String(32), nullable=False, default="active", server_default=text("'active'")
    )
    created_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True), default=_utc_now, server_default=func.now(), nullable=False
    )

    user: Mapped[User] = relationship(back_populates="memberships")
    organization: Mapped[Organization] = relationship(back_populates="memberships")
    sessions: Mapped[List["AuthSession"]] = relationship(back_populates="membership")


class AuthSession(Base):
    __tablename__ = "sessions"

    id: Mapped[str] = mapped_column(String(64), primary_key=True, default=lambda: _id("ses"))
    user_id: Mapped[str] = mapped_column(
        ForeignKey("users.id", ondelete="CASCADE"), nullable=False, index=True
    )
    membership_id: Mapped[str] = mapped_column(
        ForeignKey("memberships.id", ondelete="CASCADE"), nullable=False, index=True
    )
    token_hash: Mapped[str] = mapped_column(String(64), nullable=False, unique=True, index=True)
    auth_version: Mapped[int] = mapped_column(
        Integer, nullable=False, default=0, server_default=text("0")
    )
    expires_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False)
    revoked_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True), nullable=True)
    created_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True), default=_utc_now, server_default=func.now(), nullable=False
    )
    last_seen_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True), nullable=True)

    user: Mapped[User] = relationship(back_populates="sessions")
    membership: Mapped[Membership] = relationship(back_populates="sessions")