public function insert( $data ) {
		if ( empty( $data ) ) {
			return false;
		}

		if ( is_numeric( $data ) && $this->is_post_type( $data ) ) {
			return array( $this->get_id_index() => $data );
		}

		if ( ! empty( $data['id'] ) ) {
			if ( $this->is_post_type( $data['id'] ) ) {
				return array( $this->get_id_index() => $data['id'] );
			}
			$message = $this->messages->get_message( 'invalid-linked-post-id' );

			return new WP_Error( 'invalid-linked-post-id', $message, array( 'status' => 400 ) );
		}

		$data_request = new WP_REST_Request();
		$data_request->set_param( 'args', $this->CREATE_args() );

		$body_params = (array) $data;
		foreach ( $body_params as $key => $value ) {
			$data_request->set_param( $key, $value );
		}

		$post_id = $this->create( $data_request, true );

		if ( $post_id instanceof WP_Error ) {
			return $post_id;
		}

		return array( $this->get_id_index() => $post_id );
	}