models.py

"""
Database models for Life Coach Web Application
"""

from datetime import datetime
from flask_login import UserMixin
from flask_sqlalchemy import SQLAlchemy
from werkzeug.security import generate_password_hash, check_password_hash

# This will be set by app.py
db = SQLAlchemy()


class User(UserMixin, db.Model):
    """User model for authentication and profile."""

    __tablename__ = 'users'

    id = db.Column(db.Integer, primary_key=True)
    username = db.Column(db.String(80), unique=True, nullable=False, index=True)
    email = db.Column(db.String(120), unique=True, nullable=False, index=True)
    password_hash = db.Column(db.String(255), nullable=False)
    created_at = db.Column(db.DateTime, default=datetime.utcnow, nullable=False)

    # Relationship with conversations
    conversations = db.relationship('Conversation', backref='user', lazy=True, cascade='all, delete-orphan')

    def set_password(self, password):
        """Hash and set the user's password."""
        self.password_hash = generate_password_hash(password)

    def check_password(self, password):
        """Verify the user's password."""
        return check_password_hash(self.password_hash, password)

    def __repr__(self):
        return f'<User {self.username}>'


class Conversation(db.Model):
    """Conversation model - represents a chat session."""

    __tablename__ = 'conversations'

    id = db.Column(db.Integer, primary_key=True)
    user_id = db.Column(db.Integer, db.ForeignKey('users.id'), nullable=False, index=True)
    title = db.Column(db.String(200), default='New Conversation')
    created_at = db.Column(db.DateTime, default=datetime.utcnow, nullable=False)
    updated_at = db.Column(db.DateTime, default=datetime.utcnow, onupdate=datetime.utcnow, nullable=False)

    # Relationship with messages
    messages = db.relationship('Message', backref='conversation', lazy=True, cascade='all, delete-orphan', order_by='Message.timestamp')

    def get_message_history(self):
        """Get conversation history formatted for the model."""
        return [
            {
                'role': msg.role,
                'content': msg.content
            }
            for msg in self.messages
        ]

    def __repr__(self):
        return f'<Conversation {self.id}: {self.title}>'


class Message(db.Model):
    """Message model - individual messages in a conversation."""

    __tablename__ = 'messages'

    id = db.Column(db.Integer, primary_key=True)
    conversation_id = db.Column(db.Integer, db.ForeignKey('conversations.id'), nullable=False, index=True)
    role = db.Column(db.String(20), nullable=False)  # 'user' or 'assistant'
    content = db.Column(db.Text, nullable=False)
    timestamp = db.Column(db.DateTime, default=datetime.utcnow, nullable=False)

    def to_dict(self):
        """Convert message to dictionary for JSON serialization."""
        return {
            'id': self.id,
            'role': self.role,
            'content': self.content,
            'timestamp': self.timestamp.isoformat()
        }

    def __repr__(self):
        return f'<Message {self.id}: {self.role}>'