"""
User model for the application.
"""

from datetime import datetime
from app.database.db import db

class User(db.Model):
    """User model representing application users."""
    
    __tablename__ = 'users'
    
    id = db.Column(db.Integer, primary_key=True)
    username = db.Column(db.String(64), unique=True, nullable=False, index=True)
    email = db.Column(db.String(120), unique=True, nullable=False, index=True)
    password_hash = db.Column(db.String(128), nullable=False)
    created_at = db.Column(db.DateTime, default=datetime.utcnow)
    updated_at = db.Column(db.DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
    
    # Relationships
    chats = db.relationship('Chat', backref='user', lazy='dynamic')
    
    def __repr__(self):
        return f'<User {self.username}>'