DO $$
BEGIN
  IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'product_unit') THEN
    CREATE TYPE product_unit AS ENUM ('pcs', 'kg', 'm', 'm2', 'm3', 'bag', 'pack');
  END IF;
END;
$$;

CREATE TABLE IF NOT EXISTS products (
  id UUID PRIMARY KEY,
  sku TEXT NOT NULL UNIQUE,
  name TEXT NOT NULL,
  description TEXT NOT NULL DEFAULT '',
  category_id UUID NOT NULL REFERENCES categories(id),
  brand_id UUID NULL REFERENCES brands(id),
  unit product_unit NOT NULL,
  is_active BOOLEAN NOT NULL DEFAULT TRUE,
  created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
  updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);

DROP TRIGGER IF EXISTS trg_products_updated_at ON products;
CREATE TRIGGER trg_products_updated_at
BEFORE UPDATE ON products
FOR EACH ROW
EXECUTE FUNCTION set_updated_at();