from datetime import datetime

from sqlalchemy import Boolean, Column, DateTime, ForeignKey, String, Table
from sqlalchemy.orm import Mapped, mapped_column, relationship

from app.db import Base


user_roles = Table(
    "user_roles",
    Base.metadata,
    Column("user_id", ForeignKey("users.id"), primary_key=True),
    Column("role_id", ForeignKey("roles.id"), primary_key=True),
)

role_permissions = Table(
    "role_permissions",
    Base.metadata,
    Column("role_id", ForeignKey("roles.id"), primary_key=True),
    Column("permission_id", ForeignKey("permissions.id"), primary_key=True),
)


class User(Base):
    __tablename__ = "users"

    id: Mapped[int] = mapped_column(primary_key=True)
    phone: Mapped[str] = mapped_column(String(32), unique=True, index=True)
    name: Mapped[str] = mapped_column(String(80))
    department: Mapped[str | None] = mapped_column(String(120))
    unit_id: Mapped[int | None] = mapped_column(ForeignKey("units.id"), index=True)
    status: Mapped[str] = mapped_column(String(20), default="active", index=True)
    is_superuser: Mapped[bool] = mapped_column(Boolean, default=False)
    created_at: Mapped[datetime] = mapped_column(DateTime, default=datetime.utcnow)
    updated_at: Mapped[datetime] = mapped_column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
    last_login_at: Mapped[datetime | None] = mapped_column(DateTime)

    roles: Mapped[list["Role"]] = relationship(secondary=user_roles, back_populates="users")
    unit: Mapped["Unit | None"] = relationship(back_populates="users")


class Unit(Base):
    __tablename__ = "units"

    id: Mapped[int] = mapped_column(primary_key=True)
    name: Mapped[str] = mapped_column(String(120), unique=True, index=True)
    description: Mapped[str | None] = mapped_column(String(255))
    parent_id: Mapped[int | None] = mapped_column(ForeignKey("units.id"), index=True)
    category: Mapped[str] = mapped_column(String(20), default="company", index=True)
    created_at: Mapped[datetime] = mapped_column(DateTime, default=datetime.utcnow)

    users: Mapped[list[User]] = relationship(back_populates="unit")
    parent: Mapped["Unit | None"] = relationship(remote_side="Unit.id", back_populates="children")
    children: Mapped[list["Unit"]] = relationship(back_populates="parent")


class Role(Base):
    __tablename__ = "roles"

    id: Mapped[int] = mapped_column(primary_key=True)
    code: Mapped[str] = mapped_column(String(60), unique=True, index=True)
    name: Mapped[str] = mapped_column(String(80))
    description: Mapped[str | None] = mapped_column(String(255))

    users: Mapped[list[User]] = relationship(secondary=user_roles, back_populates="roles")
    permissions: Mapped[list["Permission"]] = relationship(secondary=role_permissions, back_populates="roles")


class Permission(Base):
    __tablename__ = "permissions"

    id: Mapped[int] = mapped_column(primary_key=True)
    code: Mapped[str] = mapped_column(String(120), unique=True, index=True)
    name: Mapped[str] = mapped_column(String(120))
    module: Mapped[str] = mapped_column(String(60), index=True)

    roles: Mapped[list[Role]] = relationship(secondary=role_permissions, back_populates="permissions")