def self.search_scope(scope, params)
    scope = scope.from_supplier_id params[:supplier_id] if params[:supplier_id].present?
    scope = scope.with_available(if params[:available] == "true" then true else false end) if params[:available].present?
    scope = scope.name_like params[:name] if params[:name].present?
    scope = scope.with_product_category_id params[:category_id] if params[:category_id].present?