models.py

from database import db
from datetime import datetime
import uuid

class User(db.Model):
    __tablename__ = 'users'
    
    id = db.Column(db.String(36), primary_key=True, default=lambda: str(uuid.uuid4()))
    username = db.Column(db.String(80), unique=True, nullable=False)
    email = db.Column(db.String(120), unique=True, nullable=False)
    password_hash = db.Column(db.String(128), nullable=False)
    created_at = db.Column(db.DateTime, default=datetime.utcnow)
    
    # Relationships
    documents = db.relationship('Document', backref='owner', lazy=True)
    chats = db.relationship('ChatHistory', backref='user', lazy=True)

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

class Document(db.Model):
    __tablename__ = 'documents'
    
    id = db.Column(db.Integer, primary_key=True)
    filename = db.Column(db.String(255), nullable=False)
    file_path = db.Column(db.String(512), nullable=False)
    file_size = db.Column(db.Integer)
    upload_date = db.Column(db.DateTime, default=datetime.utcnow)
    user_id = db.Column(db.String(36), db.ForeignKey('users.id'), nullable=False)

class ChatHistory(db.Model):
    __tablename__ = 'chat_history'
    
    id = db.Column(db.Integer, primary_key=True)
    user_id = db.Column(db.String(36), db.ForeignKey('users.id'), nullable=False)
    question = db.Column(db.Text, nullable=False)
    answer = db.Column(db.Text, nullable=False)
    document_name = db.Column(db.String(255))
    timestamp = db.Column(db.DateTime, default=datetime.utcnow)