import enum
import uuid
from datetime import datetime, timezone

from sqlalchemy import Boolean, DateTime, Enum, ForeignKey, String, UniqueConstraint, func
from sqlalchemy.orm import Mapped, mapped_column, relationship

from app.db.base import Base


class TenantRole(str, enum.Enum):
    READ_ONLY = "READ_ONLY"
    READ_WRITE = "READ_WRITE"
    TENANT_ADMIN = "TENANT_ADMIN"


class User(Base):
    __tablename__ = "users"

    id: Mapped[uuid.UUID] = mapped_column(
        primary_key=True, default=uuid.uuid4, index=True
    )
    email: Mapped[str] = mapped_column(
        String(255), unique=True, nullable=False, index=True
    )
    hashed_password: Mapped[str] = mapped_column(String(255), nullable=False)
    full_name: Mapped[str] = mapped_column(String(255), nullable=False)
    is_active: Mapped[bool] = mapped_column(Boolean, default=True, nullable=False)
    is_superadmin: Mapped[bool] = mapped_column(Boolean, default=False, nullable=False)

    created_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True),
        server_default=func.now(),
        nullable=False,
    )
    updated_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True),
        server_default=func.now(),
        onupdate=lambda: datetime.now(timezone.utc),
        nullable=False,
    )

    # Relationships
    user_tenants: Mapped[list["UserTenant"]] = relationship(
        "UserTenant", back_populates="user", cascade="all, delete-orphan"
    )


class UserTenant(Base):
    __tablename__ = "user_tenants"
    __table_args__ = (UniqueConstraint("user_id", "tenant_id", name="uq_user_tenant"),)

    user_id: Mapped[uuid.UUID] = mapped_column(
        ForeignKey("users.id", ondelete="CASCADE"),
        primary_key=True,
    )
    tenant_id: Mapped[uuid.UUID] = mapped_column(
        ForeignKey("tenants.id", ondelete="CASCADE"),
        primary_key=True,
    )
    role: Mapped[TenantRole] = mapped_column(
        Enum(TenantRole, name="tenant_role"),
        nullable=False,
        default=TenantRole.READ_ONLY,
    )

    # Relationships
    user: Mapped["User"] = relationship("User", back_populates="user_tenants")
    tenant: Mapped["Tenant"] = relationship(  # noqa: F821
        "Tenant", back_populates="user_tenants"
    )