-- PostgreSQL 17 — схема магазина

CREATE TABLE IF NOT EXISTS users (
  id SERIAL PRIMARY KEY,
  email TEXT NOT NULL UNIQUE,
  password_hash TEXT NOT NULL,
  name TEXT NOT NULL,
  created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);

CREATE TABLE IF NOT EXISTS categories (
  id SERIAL PRIMARY KEY,
  slug TEXT NOT NULL UNIQUE,
  name TEXT NOT NULL
);

CREATE TABLE IF NOT EXISTS products (
  id SERIAL PRIMARY KEY,
  category_id INTEGER REFERENCES categories(id) ON DELETE SET NULL,
  slug TEXT NOT NULL UNIQUE,
  name TEXT NOT NULL,
  description TEXT NOT NULL DEFAULT '',
  price_cents INTEGER NOT NULL CHECK (price_cents >= 0),
  stock INTEGER NOT NULL DEFAULT 0 CHECK (stock >= 0),
  image_url TEXT,
  created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);

CREATE TABLE IF NOT EXISTS orders (
  id SERIAL PRIMARY KEY,
  user_id INTEGER NOT NULL REFERENCES users(id),
  status TEXT NOT NULL DEFAULT 'pending'
    CHECK (status IN ('pending', 'paid', 'shipped', 'cancelled')),
  total_cents INTEGER NOT NULL CHECK (total_cents >= 0),
  customer_name TEXT NOT NULL,
  customer_email TEXT NOT NULL,
  customer_phone TEXT NOT NULL DEFAULT '',
  address TEXT NOT NULL,
  created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);

CREATE TABLE IF NOT EXISTS order_items (
  id SERIAL PRIMARY KEY,
  order_id INTEGER NOT NULL REFERENCES orders(id) ON DELETE CASCADE,
  product_id INTEGER NOT NULL REFERENCES products(id),
  quantity INTEGER NOT NULL CHECK (quantity > 0),
  price_cents INTEGER NOT NULL CHECK (price_cents >= 0)
);

CREATE INDEX IF NOT EXISTS idx_products_category ON products(category_id);
CREATE INDEX IF NOT EXISTS idx_orders_user ON orders(user_id);
CREATE INDEX IF NOT EXISTS idx_products_name ON products(name);