Form.ts

///
/// Copyright OmniFaces
///
/// Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with
/// the License. You may obtain a copy of the License at
///
///     https://www.apache.org/licenses/LICENSE-2.0
///
/// Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on
/// an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
/// specific language governing permissions and limitations under the License.
///

import { VIEW_STATE_PARAM } from "./OmniFaces";
import { CLIENT_WINDOW_PARAM } from "./OmniFaces";
import { Util } from "./Util";

/**
 * Form partial submit.
 * 
 * @author Bauke Scholtz
 * @see org.omnifaces.component.input.Form
 * @since 3.0
 */
export module Form {

	// Private static functions ---------------------------------------------------------------------------------------

	function init() {
		const faces = window.faces || window.jsf;

		if (faces) { // Standard JSF API.
			const originalAjaxRequest = faces.ajax.request;

			faces.ajax.request = function(source: HTMLElement, event: any, options: any) {
				const originalGetViewState = faces.getViewState;

				faces.getViewState = function(form: HTMLFormElement) {
					const originalViewState = originalGetViewState(form);

					if (form.dataset["partialsubmit"] != "true") {
						return originalViewState;
					}

					const execute = options ? options.execute : null;

					if (!execute || execute.indexOf("@form") != -1 || execute.indexOf("@all") != -1) {
						return originalViewState;
					}

					let executeIds: string[] = [];
					let encodedExecuteIds: string[] = [];

					if (execute.indexOf("@none") == -1) {
						executeIds = execute.replace("@this", source.id).split(" ");
						encodedExecuteIds = executeIds.map(encodeURIComponent);
					}

					encodedExecuteIds.push(VIEW_STATE_PARAM);
					encodedExecuteIds.push(CLIENT_WINDOW_PARAM);

					const partialViewState: string[] = [];

					originalViewState.replace(/([^=&]+)=([^&]*)/g, function(_entry: any, key: string, value: string) {
						if (encodedExecuteIds.indexOf(key) > -1 || containsNamedChild(executeIds, key)) {
							partialViewState.push(key + "=" + value);
						}
					}); 

					return partialViewState.join("&");
				}

				originalAjaxRequest(source, event, options);
			}
		}
	}

	function containsNamedChild(executeIds: string[], key: string) {
		var name = key.replace("%3A", "\\:");

		try {
			for (let executeId of executeIds) {
				var parent = document.getElementById(executeId);

				if (parent && parent.querySelector("[name='" + name + "']")) {
					return true;
				}
			}
		}
		catch (e) {
			console.warn("Cannot determine if " + executeIds + " contains child " + name, e);
		}

		return false;		
	}

	// Global initialization ------------------------------------------------------------------------------------------

	Util.addOnloadListener(init);

}