"""
User and Product models using SQLAlchemy ORM.
"""
from flask_login import UserMixin
from flask_sqlalchemy import SQLAlchemy
from datetime import datetime

# Initialize SQLAlchemy
db = SQLAlchemy()


class User(UserMixin, db.Model):
    """User model for storing user accounts."""
    __tablename__ = 'users'
    
    id = db.Column(db.Integer, primary_key=True)
    full_name = db.Column(db.String(120), nullable=False)
    email = db.Column(db.String(120), unique=True, nullable=False, index=True)
    password_hash = db.Column(db.String(255), nullable=False)
    profile_picture = db.Column(db.String(255), default='default.png')
    is_admin = db.Column(db.Boolean, default=False, nullable=False)
    created_at = db.Column(db.DateTime, default=datetime.utcnow)
    
    # Relationship to cart items
    cart_items = db.relationship('CartItem', backref='user', lazy=True, cascade='all, delete-orphan')
    
    def __repr__(self):
        """String representation of the user."""
        return f'<User {self.email}>'


class Product(db.Model):
    """Product model for storing product information."""
    __tablename__ = 'products'
    
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(100), nullable=False)
    price = db.Column(db.Float, nullable=False)
    image_url = db.Column(db.String(255))
    badge = db.Column(db.String(50))  # e.g., "Popular", "New", "Best Seller"
    description = db.Column(db.String(500))
    quantity_available = db.Column(db.Integer, default=100)  # Default 100 in stock
    created_at = db.Column(db.DateTime, default=datetime.utcnow)
    # Relationship to cart items
    cart_items = db.relationship('CartItem', backref='product', lazy=True, cascade='all, delete-orphan')
    
    def __repr__(self):
        """String representation of the product."""
        return f'<Product {self.name}>'


class CartItem(db.Model):
    """CartItem model for storing user shopping cart items."""
    __tablename__ = 'cart_items'
    
    id = db.Column(db.Integer, primary_key=True)
    user_id = db.Column(db.Integer, db.ForeignKey('users.id'), nullable=False)
    product_id = db.Column(db.Integer, db.ForeignKey('products.id'), nullable=False)
    quantity = db.Column(db.Integer, default=1, nullable=False)
    added_at = db.Column(db.DateTime, default=datetime.utcnow)
    
    def __repr__(self):
        """String representation of a cart item."""
        return f'<CartItem user_id={self.user_id} product_id={self.product_id}>'


class Order(db.Model):
    """Order model for storing completed purchases."""
    __tablename__ = 'orders'
    
    id = db.Column(db.Integer, primary_key=True)
    user_id = db.Column(db.Integer, db.ForeignKey('users.id'), nullable=False)
    total_amount = db.Column(db.Float, nullable=False)
    status = db.Column(db.String(50), default='pending', nullable=False)  # pending, processing, completed, cancelled
    created_at = db.Column(db.DateTime, default=datetime.utcnow)
    
    # Relationship to order items
    items = db.relationship('OrderItem', backref='order', lazy=True, cascade='all, delete-orphan')
    user = db.relationship('User', backref='orders')
    
    def __repr__(self):
        return f'<Order {self.id} - {self.user.email}>'


class OrderItem(db.Model):
    """OrderItem model for storing individual items in an order."""
    __tablename__ = 'order_items'
    
    id = db.Column(db.Integer, primary_key=True)
    order_id = db.Column(db.Integer, db.ForeignKey('orders.id'), nullable=False)
    product_id = db.Column(db.Integer, db.ForeignKey('products.id'), nullable=False)
    product_name = db.Column(db.String(100), nullable=False)
    price = db.Column(db.Float, nullable=False)
    quantity = db.Column(db.Integer, default=1, nullable=False)
    
    product = db.relationship('Product')
    
    def __repr__(self):
        return f'<OrderItem {self.id} - {self.product_name}>'