-- v0.403 R1: Product reviews (buyer reviews on purchased products)
-- UNIQUE(product_id, buyer_id) - one review per buyer per product

DO $$
BEGIN
  IF EXISTS (SELECT 1 FROM information_schema.tables WHERE table_schema = 'public' AND table_name = 'products')
     AND EXISTS (SELECT 1 FROM information_schema.tables WHERE table_schema = 'public' AND table_name = 'orders') THEN
    IF NOT EXISTS (SELECT 1 FROM information_schema.tables WHERE table_schema = 'public' AND table_name = 'product_reviews') THEN
      CREATE TABLE product_reviews (
        id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
        product_id UUID NOT NULL REFERENCES products(id) ON DELETE CASCADE,
        buyer_id UUID NOT NULL REFERENCES users(id) ON DELETE CASCADE,
        order_id UUID NOT NULL REFERENCES orders(id) ON DELETE CASCADE,
        rating INTEGER NOT NULL CHECK (rating >= 1 AND rating <= 5),
        comment TEXT,
        created_at TIMESTAMPTZ DEFAULT NOW(),
        UNIQUE(product_id, buyer_id)
      );
      CREATE INDEX idx_product_reviews_product_id ON product_reviews(product_id);
      CREATE INDEX idx_product_reviews_buyer_id ON product_reviews(buyer_id);
    END IF;
  END IF;
END $$;