function Delete_All_Products()
{
    global $wpdb;
    global $items_table_name;
    $Products = $wpdb->get_results("SELECT Item_ID FROM {$items_table_name}");
    if (is_array($Products)) {
        foreach ($Products as $Product) {
            if ($Product->Item_ID != "") {
                Delete_UPCP_Product($Product->Item_ID);
            }
        }
    }
    $update = __("Products have been successfully deleted.", 'UPCP');
    $user_update = array("Message_Type" => "Update", "Message" => $update);
    return $user_update;
}
function Update_UPCP_Content()
{
    global $upcp_message;
    if (isset($_GET['Action'])) {
        switch ($_GET['Action']) {
            case "UPCP_EditProduct":
            case "UPCP_AddProduct":
                $upcp_message = Add_Edit_Product();
                break;
            case "UPCP_DeleteProduct":
                $upcp_message = Delete_UPCP_Product($_GET['Item_ID']);
                break;
            case "UPCP_MassDeleteProducts":
                $upcp_message = Mass_Delete_Products();
                break;
            case "UPCP_DeleteAllProducts":
                $upcp_message = Delete_All_Products();
                break;
            case "UPCP_AddProductSpreadsheet":
                $upcp_message = Add_Products_From_Spreadsheet();
                break;
            case "UPCP_ExportToExcel":
                $upcp_message = UPCP_Export_To_Excel();
                break;
            case "UPCP_AddProductVideos":
                $upcp_message = Prepare_Add_Product_Video();
                break;
            case "UPCP_DeleteProductVideo":
                $upcp_message = Delete_Product_Video($_GET['Item_Video_ID']);
                break;
            case "UPCP_AddOptionalImage":
            case "UPCP_EditOptionalImage":
                $upcp_message = Add_Edit_Optional_Images();
                break;
            case "UPCP_DeleteOptionalImage":
                $upcp_message = Delete_Optional_Image($_GET['Item_Optional_Image_ID']);
                break;
            case "UPCP_AddProductImage":
                $upcp_message = Prepare_Add_Product_Image();
                break;
            case "UPCP_DeleteProductImage":
                $upcp_message = Delete_Product_Image();
                break;
            case "UPCP_EditCategory":
            case "UPCP_AddCategory":
                $upcp_message = Add_Edit_Category();
                break;
            case "UPCP_DeleteCategory":
                $upcp_message = Delete_UPCP_Category($_GET['Category_ID']);
                break;
            case "UPCP_MassDeleteCategories":
                $upcp_message = Mass_Delete_Categories();
                break;
            case "UPCP_EditCatalogue":
            case "UPCP_AddCatalogue":
                $upcp_message = Add_Edit_Catalogue();
                break;
            case "UPCP_DeleteCatalogue":
                $upcp_message = Delete_UPCP_Catalogue($_GET['Catalogue_ID']);
                break;
            case "UPCP_MassDeleteCatalogues":
                $upcp_message = Mass_Delete_Catalogues();
                break;
            case "UPCP_DeleteCatalogueItem":
                $upcp_message = Delete_Products_Catalogue();
                break;
            case "UPCP_EditSubCategory":
            case "UPCP_AddSubCategory":
                $upcp_message = Add_Edit_SubCategory();
                break;
            case "UPCP_DeleteSubCategory":
                $upcp_message = Delete_UPCP_SubCategory($_GET['SubCategory_ID']);
                break;
            case "UPCP_MassDeleteSubCategories":
                $upcp_message = Mass_Delete_SubCategories();
                break;
            case "UPCP_EditTag":
            case "UPCP_AddTag":
                $upcp_message = Add_Edit_Tag();
                break;
            case "UPCP_DeleteTag":
                $upcp_message = Delete_UPCP_Tag($_GET['Tag_ID']);
                break;
            case "UPCP_MassDeleteTags":
                $upcp_message = Mass_Delete_UPCP_Tags();
                break;
            case "UPCP_DeleteTaggedItem":
                $upcp_message = Delete_Products_Tags();
                break;
            case "UPCP_AddTagGroup":
            case "UPCP_EditTagGroup":
                $upcp_message = Add_Edit_Tag_Group();
                break;
            case "UPCP_DeleteTagGroup":
                $upcp_message = Delete_UPCP_Tag_Group($_GET['Tag_Group_ID']);
                break;
            case "UPCP_EditCustomField":
            case "UPCP_AddCustomField":
                $upcp_message = Add_Edit_Custom_Field();
                break;
            case "UPCP_DeleteCustomField":
                $upcp_message = Delete_UPCP_Custom_Field($_GET['Field_ID']);
                break;
            case "UPCP_MassDeleteCustomFields":
                $upcp_message = Mass_Delete_UPCP_Custom_Fields();
                break;
            case "UPCP_UpdateOptions":
                $upcp_message = Update_UPCP_Options();
                break;
            case "UPCP_RestoreDefaultStyles":
                $upcp_message = UPCP_Set_Default_Style_Values();
                break;
            case "UPCP_RestoreDefaultPPLayout":
                $upcp_message = Restore_Default_PP_Layout();
                break;
            case "UPCP_RestoreDefaultPPLayoutMobile":
                $upcp_message = Restore_Default_PP_Layout_Mobile();
                break;
            case "UPCP_UpdateTabs":
                $upcp_message = UPCP_Save_Additional_Tabs();
                break;
            default:
                $upcp_message = __("The form has not worked correctly. Please contact the plugin developer.", 'UPCP');
                break;
        }
    }
}