from __future__ import annotations
from typing import Optional

import enum
import uuid
from datetime import datetime

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

from app.db.base_class import Base


class UserStatus(str, enum.Enum):
    PENDING = "PENDING"
    ACTIVE = "ACTIVE"
    REJECTED = "REJECTED"
    DISABLED = "DISABLED"


class User(Base):
    __tablename__ = "users"

    id: Mapped[uuid.UUID] = mapped_column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
    email: Mapped[str] = mapped_column(String(255), unique=True, index=True, nullable=False)
    password_hash: Mapped[str] = mapped_column(String(255), nullable=False)
    full_name: Mapped[str] = mapped_column(String(255), nullable=False)
    clinical_department: Mapped[str] = mapped_column(String(255), nullable=False)
    is_admin: Mapped[bool] = mapped_column(Boolean, nullable=False, server_default="false", default=False)
    status: Mapped[UserStatus] = mapped_column(
        Enum(UserStatus, name="user_status"),
        nullable=False,
        server_default=UserStatus.PENDING.value,
        default=UserStatus.PENDING,
    )
    created_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True),
        nullable=False,
        server_default=func.now(),
    )
    updated_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True),
        nullable=False,
        server_default=func.now(),
        onupdate=func.now(),
    )
    approved_by: Mapped[Optional[uuid.UUID]] = mapped_column(
        UUID(as_uuid=True),
        ForeignKey("users.id"),
        nullable=True,
    )
    approved_at: Mapped[Optional[datetime]] = mapped_column(DateTime(timezone=True), nullable=True)
    avatar_url: Mapped[Optional[str]] = mapped_column(String(500), nullable=True)

    @property
    def is_active(self) -> bool:  # compatibility helper for existing checks
        return self.status == UserStatus.ACTIVE

    @property
    def username(self) -> str:  # backward compatibility for existing UI copy
        return self.email