public function create_item( $request ) {
		// Setting context.
		$request->set_param( 'context', 'edit' );

		// Prepare the message or the reply arguments.
		$args = array(
			'sender_id'  => $request['sender_id'],
			'thread_id'  => 0,
			'subject'    => $request['subject'],
			'content'    => $request['message'],
			'recipients' => $request['recipients'],
		);

		$error = new WP_Error(
			'bp_rest_messages_create_failed',
			__( 'There was an error trying to create the message.', 'buddypress' ),
			array(
				'status' => 500,
			)
		);

		// Replying to an existing Thread ?
		if ( $request['id'] ) {
			// Try to get the thread.
			$thread = $this->get_thread_object( $request['id'] );

			// Validate the Thread exists.
			if ( ! $thread->thread_id ) {
				return $error;
			}

			$args['thread_id']  = (int) $thread->thread_id;
			$args['recipients'] = wp_parse_id_list( wp_list_pluck( $thread->recipients, 'user_id' ) );
		}

		if ( ! $args['recipients'] ) {
			return new WP_Error(
				'bp_rest_messages_missing_recipients',
				__( 'Please provide some recipients for your message or reply.', 'buddypress' ),
				array(
					'status' => 400,
				)
			);
		}

		// Create the message or the reply.
		$thread_id = messages_new_message( $args );

		// Validate it created a Thread or was added to it.
		if ( ! $thread_id ) {
			return $error;
		}

		// Make sure to get the newest message to update REST Additional fields.
		$thread        = $this->get_thread_object( $thread_id );
		$last_message  = wp_list_filter( $thread->messages, array( 'id' => $thread->last_message_id ) );
		$last_message  = reset( $last_message );
		$fields_update = $this->update_additional_fields_for_object( $last_message, $request );

		if ( is_wp_error( $fields_update ) ) {
			return $fields_update;
		}

		$retval = array(
			$this->prepare_response_for_collection(
				$this->prepare_item_for_response( $thread, $request )
			),
		);

		$response = rest_ensure_response( $retval );

		/**
		 * Fires after a message is created via the REST API.
		 *
		 * @since 5.0.0
		 *
		 * @param BP_Messages_Thread $thread  Thread object.
		 * @param WP_REST_Response   $retval  The response data.
		 * @param WP_REST_Request    $request The request sent to the API.
		 */
		do_action( 'bp_rest_messages_create_item', $thread, $response, $request );

		return $response;
	}