"""User entity for authentication."""
from datetime import datetime
from sqlalchemy import Column, Integer, String, DateTime
from sqlalchemy.orm import relationship
from database import Base

class User(Base):
    """Registered user with authentication credentials."""

    __tablename__ = "users_001_todo"

    id = Column(Integer, primary_key=True, autoincrement=True)
    email = Column(String(255), unique=True, index=True, nullable=False)
    password_hash = Column(String(255), nullable=False)  # bcrypt hash is ~60 chars
    created_at = Column(DateTime, default=datetime.utcnow, nullable=False)
    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow, nullable=False)

    # Relationship to todos - enables cascading deletes
    todos = relationship("Todo", back_populates="user", cascade="all, delete-orphan")

    def __repr__(self) -> str:
        return f"<User(id={self.id}, email={self.email})>"

    # For Pydantic serialization
    def to_dict(self):
        return {
            "id": self.id,
            "email": self.email,
            "created_at": self.created_at.isoformat(),
            "updated_at": self.updated_at.isoformat(),
        }