ponse Response object on success, or WP_Error object on failure.
	 */
	protected function update_items( $request ) {
		return new \WP_Error( 'invalid-method', sprintf( "Method '%s' not implemented. Must be overridden in subclass.", __METHOD__ ), [ 'status' => 405 ] );
	}

	/**
	 * Updates one item.
	 *
	 * @param string $id id of request item.
	 * @param \WP_REST_Request $request Full data about the request.
	 *
	 * @return \WP_Error|\WP_REST_Response Response object on success, or WP_Error object on failure.
	 */
	protected function update_item( $id, $request ) {
		return new \WP_Error( 'invalid-method', sprintf( "Method '%s' not implemented. Must be overridden in subclass.", __METHOD__ ), [ 'status' => 405 ] );
	}

	/**
	 * Delete multiple items.
	 *
	 * @param \WP_REST_Request $request Full data about the request.
	 *
	 * @return \WP_Error|\WP_REST_Response Response object on success, or WP_Error object on failure.
	 */
	protected function delete_items( $request ) {
		return new \WP_Error( 'invalid-method', sprintf( "Method '%s' not implemented. Must be overridden in subclass.", __METHOD__ ), [ 'status' => 405 ] );
	}

	/**
	 * Delete one item.
	 *
	 * @param string $id id of request item.
	 * @param \WP_REST_Request $request Full data about the request.
	 *
	 * @return \WP_Error|\WP_REST_Response Response object on success, or WP_Error object on failure.
	 */
	protected function delete_item( $id, $request ) {
		return new \WP_Error( 'invalid-method', sprintf( "Method '%s' not implemented. Must be overridden in subclass.", __METHOD__ ), [ 'status' => 405 ] );
	}

	/**
	 * Register the endpoint.
	 *
	 * By default: register get items route.
	 */
	protected function register() {
		$this->register_items_route();
	}

	protected function register_route( $route = '', $methods = WP_REST_Server::READABLE, $args = [] ) {
		if ( ! in_array( $methods, self::AVAILABLE_METHODS, true ) ) {
			trigger_error( "Invalid method: '$methods'.", E_USER_ERROR ); // phpcs:ignore
		}

		$route = $this->get_base_route() . $route;

		$this->routes [] = [
			'args' => $args,
			'route' => $route,
		];

		/**
		 * Determine behaviour of `base_callback()` and `get_permission_callback()`:
		 * For `base_callback()` which applying the action.
		 * Whether it's a one item request and should call `get_item_permission_callback()` or it's mutil items request and should call `get_items_permission_callback()`.
		 */
		$is_multi = ! empty( $args['is_multi'] );

		if ( $is_multi ) {
			unset( $args['is_multi'] );
		}

		$callback = function ( $request ) use ( $methods, $args, $is_multi ) {
			return $this->base_callback( $methods, $request, $is_multi );
		};

		return register_rest_route( $this->controller->get_namespace(), $route, [
			[
				'args' => $args,
				'methods' => $methods,
				'callback' => $callback,
				'permission_callback' => function ( $request ) {
					return $this->get_permission_callback( $request );
				},
			],
		] );
	}

	/**
	 * Register items route.
	 *
	 * @param string $methods
	 * @param array $args
	 */
	public function register_items_route( $methods = WP_REST_Server::READABLE, $args = [] ) {
		$args['is_multi'] = true;

		$this->register_route( '', $methods, $args );
	}

	/**
	 * Register item route.
	 *
	 * @param string $route
	 * @param array $args
	 * @param string $methods
	 */
	public function register_item_route( $methods = WP_REST_Server::READABLE, $args = [], $route = '/' ) {
		if ( ! empty( $args['id_arg_name'] ) ) {
			$this->id_arg_name = $args['id_arg_name'];

			unset( $args['id_arg_name'] );
		}

		if ( ! empty( $args['id_arg_type_regex'] ) ) {
			$this->id_arg_type_regex = $args['id_arg_type_regex'];

			unset( $args['id_arg_type_regex'] );
		}

		$args = array_merge( [
			$this->id_arg_name => [
				'description' => 'Unique identifier for the object.',
				'type' => 'string',
				'required' => true,
			],
		], $args );

		$route .= '(?P<' . $this->id_arg_name . '>' . $this->id_arg_type_regex . ')';

		$this->item_route = [
			'args' => $args,
			'route' => $route,
		];

		$this->register_route( $route, $methods, $args );
	}

	/**
	 * Base callback.
	 * All reset requests from the client should pass this function.
	 *
	 * @param string $methods
	 * @param \WP_REST_Request $request
	 * @param bool $is_multi
	 * @param array $args
	 *
	 * @return mixed|\WP_Error|\WP_HTTP_Response|\WP_REST_Response
	 */
	public function base_callback( $methods, $request, $is_multi = false, $args = [] ) {
		if ( $request ) {
			$json_params = $request->get_json_params();

			if ( $json_params ) {
				$request->set_body_params( $json_params );
			}
		}

		$args = wp_parse_args( $args, [
			'is_debug' => ( defined( 'WP_DEBUG' ) && WP_DEBUG ),
		] );

		$result = new \WP_Error( 'invalid_methods', 'route not supported.' );

		$request->set_param( 'is_multi', $is_multi );

		try {
			switch ( $methods ) {
				case WP_REST_Server::READABLE:
					$result = $is_multi ? $this->get_items( $request ) : $this->get_item( $request->get_param( 'id' ), $request );
					break;

				case WP_REST_Server::CREATABLE:
					$result = $is_multi ? $this->create_items( $request ) : $this->create_item( $request->get_param( 'id' ), $request );
					break;

				case WP_REST_Server::EDITABLE:
					$result = $is_multi ? $this->update_items( $request ) : $this->update_item( $request->get_param( 'id' ), $request );
					break;

				case WP_REST_Server::DELETABLE:
					$result = $is_multi ? $this->delete_items( $request ) : $this->delete_item( $request->get_param( 'id' ), $request );
					break;
			}
		} catch ( Data_Exception $e ) {
			$result = $e->to_wp_error();
		} catch ( \Exception $e ) {
			if ( empty( $args['is_debug'] ) ) {
				$result = ( new Error_500() )->to_wp_error();
			} else {
				// For frontend.
				$exception_mapping = [
					'trace' => $e->getTrace(),
					'file' => $e->getFile(),
					'line' => $e->getLine(),
				];

				$e->debug = $exception_mapping;

				$result = ( new Data_Exception( $e->getMessage(), $e->getCode(), $e ) )->to_wp_error();
			}
		}

		return rest_ensure_response( $result );
	}

	/**
	 * Constructor.
	 *
	 * run `$this->register()`.
	 *
	 * @param \Elementor\Data\V2\Base\Controller $controller
	 * @param string $route
	 */
	protected function __construct( Controller $controller, $route ) {
		$this->controller = $controller;
		$this->route = $this->ensure_slashes( $route );

		$this->register();
	}
}