// This file is part of Moodle - http://moodle.org/
//
// Moodle is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Moodle is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Moodle. If not, see <http://www.gnu.org/licenses/>.
/**
* Display a form in a modal dialogue
*
* Example:
* import ModalForm from 'core_form/modalform';
*
* const modalForm = new ModalForm({
* formClass: 'pluginname\\form\\formname',
* modalConfig: {title: 'Here comes the title'},
* args: {categoryid: 123},
* returnFocus: e.target,
* });
* modalForm.addEventListener(modalForm.events.FORM_SUBMITTED, (c) => window.console.log(c.detail));
* modalForm.show();
*
* See also https://docs.moodle.org/dev/Modal_and_AJAX_forms
*
* @module core_form/modalform
* @copyright 2018 Mitxel Moriana <mitxel@tresipunt.>
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
import Ajax from 'core/ajax';
import * as FormChangeChecker from 'core_form/changechecker';
import * as FormEvents from 'core_form/events';
import Fragment from 'core/fragment';
import ModalEvents from 'core/modal_events';
import ModalFactory from 'core/modal_factory';
import Notification from 'core/notification';
import Pending from 'core/pending';
export default class ModalForm {
/**
* Various events that can be observed.
*
* @type {Object}
*/
events = {
// Form was successfully submitted - the response is passed to the event listener.
// Cancellable (but it's hardly ever needed to cancel this event).
FORM_SUBMITTED: 'core_form_modalform_formsubmitted',
// Cancel button was pressed.
// Cancellable (but it's hardly ever needed to cancel this event).
FORM_CANCELLED: 'core_form_modalform_formcancelled',
// User attempted to submit the form but there was client-side validation error.
CLIENT_VALIDATION_ERROR: 'core_form_modalform_clientvalidationerror',
// User attempted to submit the form but server returned validation error.
SERVER_VALIDATION_ERROR: 'core_form_modalform_validationerror',
// Error occurred while performing request to the server.
// Cancellable (by default calls Notification.exception).
ERROR: 'core_form_modalform_error',
// Right after user pressed no-submit button,
// listen to this event if you want to add JS validation or processing for no-submit button.
// Cancellable.
NOSUBMIT_BUTTON_PRESSED: 'core_form_modalform_nosubmitbutton',
// Right after user pressed submit button,
// listen to this event if you want to add additional JS validation or confirmation dialog.
// Cancellable.
SUBMIT_BUTTON_PRESSED: 'core_form_modalform_submitbutton',
// Right after user pressed cancel button,
// listen to this event if you want to add confirmation dialog.
// Cancellable.
CANCEL_BUTTON_PRESSED: 'core_form_modalform_cancelbutton',
// Modal was loaded and this.modal is available (but the form content may not be loaded yet).
LOADED: 'core_form_modalform_loaded',
};
/**
* Constructor
*
* Shows the required form inside a modal dialogue
*
* @param {Object} config parameters for the form and modal dialogue:
* @paramy {String} config.formClass PHP class name that handles the form (should extend \core_form\modal )
* @paramy {Object} config.modalConfig modal config - title, type, etc.
* Default: {removeOnClose: true, type: ModalFactory.types.SAVE_CANCEL}
* @paramy {Object} config.args Arguments for the initial form rendering (for example, id of the edited entity)
* @paramy {String} config.saveButtonText the text to display on the Modal "Save" button (optional)
* @paramy {String} config.saveButtonClasses additional CSS classes for the Modal "Save" button
* @paramy {HTMLElement} config.returnFocus element to return focus to after the dialogue is closed
*/
constructor(config) {
this.modal = null;
this.config = config;
this.config.modalConfig = {
removeOnClose: true,
type: ModalFactory.types.SAVE_CANCEL,
large: true,
...(this.config.modalConfig || {}),
};
this.config.args = this.config.args || {};
this.futureListeners = [];
}
/**
* Initialise the modal and shows it
*
* @return {Promise}
*/
show() {
const pendingPromise = new Pending('core_form/modalform:init');
return ModalFactory.create(this.config.modalConfig)
.then((modal) => {
this.modal = modal;
// Retrieve the form and set the modal body. We can not set the body in the modalConfig,
// we need to make sure that the modal already exists when we render the form. Some form elements
// such as date_selector inspect the existing elements on the page to find the highest z-index.
const formParams = new URLSearchParams(Object.entries(this.config.args || {}));
const bodyContent = this.getBody(formParams.toString());
this.modal.setBodyContent(bodyContent);
bodyContent.catch(Notification.exception);
// After successfull submit, when we press "Cancel" or close the dialogue by clicking on X in the top right corner.
this.modal.getRoot().on(ModalEvents.hidden, () => {
this.notifyResetFormChanges();
this.modal.destroy();
// Focus on the element that actually launched the modal.
if (this.config.returnFocus) {
this.config.returnFocus.focus();
}
});
// Add the class to the modal dialogue.
this.modal.getModal().addClass('modal-form-dialogue');
// We catch the press on submit buttons in the forms.
this.modal.getRoot().on('click', 'form input[type=submit][data-no-submit]',
(e) => {
e.preventDefault();
const event = this.trigger(this.events.NOSUBMIT_BUTTON_PRESSED, e.target);
if (!event.defaultPrevented) {
this.processNoSubmitButton(e.target);
}
});
// We catch the form submit event and use it to submit the form with ajax.
this.modal.getRoot().on('submit', 'form', (e) => {
e.preventDefault();
const event = this.trigger(this.events.SUBMIT_BUTTON_PRESSED);
if (!event.defaultPrevented) {
this.submitFormAjax();
}
});
// Change the text for the save button.
if (typeof this.config.saveButtonText !== 'undefined' &&
typeof this.modal.setSaveButtonText !== 'undefined') {
this.modal.setSaveButtonText(this.config.saveButtonText);
}
// Set classes for the save button.
if (typeof this.config.saveButtonClasses !== 'undefined') {
this.setSaveButtonClasses(this.config.saveButtonClasses);
}
// When Save button is pressed - submit the form.
this.modal.getRoot().on(ModalEvents.save, (e) => {
e.preventDefault();
this.modal.getRoot().find('form').submit();
});
// When Cancel button is pressed - allow to intercept.
this.modal.getRoot().on(ModalEvents.cancel, (e) => {
const event = this.trigger(this.events.CANCEL_BUTTON_PRESSED);
if (event.defaultPrevented) {
e.preventDefault();
}
});
this.futureListeners.forEach(args => this.modal.getRoot()[0].addEventListener(...args));
this.futureListeners = [];
this.trigger(this.events.LOADED, null, false);
return this.modal.show();
})
.then(pendingPromise.resolve);
}
/**
* Triggers a custom event
*
* @private
* @param {String} eventName
* @param {*} detail
* @param {Boolean} cancelable
* @return {CustomEvent<unknown>}
*/
trigger(eventName, detail = null, cancelable = true) {
const e = new CustomEvent(eventName, {detail, cancelable});
this.modal.getRoot()[0].dispatchEvent(e);
return e;
}
/**
* Add listener for an event
*
* @param {array} args
* @example:
* const modalForm = new ModalForm(...);
* dynamicForm.addEventListener(modalForm.events.FORM_SUBMITTED, e => {
* window.console.log(e.detail);
* });
*/
addEventListener(...args) {
if (!this.modal) {
this.futureListeners.push(args);
} else {
this.modal.getRoot()[0].addEventListener(...args);
}
}
/**
* Get form contents (to be used in ModalForm.setBodyContent())
*
* @param {String} formDataString form data in format of a query string
* @method getBody
* @private
* @return {Promise}
*/
getBody(formDataString) {
const params = {
formdata: formDataString,
form: this.config.formClass
};
const pendingPromise = new Pending('core_form/modalform:form_body');
return Ajax.call([{
methodname: 'core_form_dynamic_form',
args: params
}])[0]
.then(response => {
pendingPromise.resolve();
return {html: response.html, js: Fragment.processCollectedJavascript(response.javascript)};
});
}
/**
* On exception during form processing. Caller may override
*
* @param {Object} exception
*/
onSubmitError(exception) {
const event = this.trigger(this.events.ERROR, exception);
if (event.defaultPrevented) {
return;
}
Notification.exception(exception);
}
/**
* Notifies listeners that form dirty state should be reset.
*
* @fires event:formSubmittedByJavascript
*/
notifyResetFormChanges() {
const form = this.getFormNode();
FormEvents.notifyFormSubmittedByJavascript(this.getFormNode(), true);
if (!form) {
return;
}
FormChangeChecker.resetFormDirtyState(this.getFormNode());
}
/**
* Get the form node from the Dialogue.
*
* @returns {HTMLFormElement}
*/
getFormNode() {
return this.modal.getRoot().find('form')[0];
}
/**
* Click on a "submit" button that is marked in the form as registerNoSubmitButton()
*
* @param {Element} button button that was pressed
* @fires event:formSubmittedByJavascript
*/
processNoSubmitButton(button) {
const form = this.getFormNode();
if (!form) {
return;
}
FormEvents.notifyFormSubmittedByJavascript(form, true);
// Add the button name to the form data and submit it.
let formData = this.modal.getRoot().find('form').serialize();
formData = formData + '&' + encodeURIComponent(button.getAttribute('name')) + '=' +
encodeURIComponent(button.getAttribute('value'));
const bodyContent = this.getBody(formData);
this.modal.setBodyContent(bodyContent);
bodyContent.catch(Notification.exception);
}
/**
* Validate form elements
* @return {Boolean} Whether client-side validation has passed, false if there are errors
* @fires event:formSubmittedByJavascript
*/
validateElements() {
FormEvents.notifyFormSubmittedByJavascript(this.getFormNode());
// Now the change events have run, see if there are any "invalid" form fields.
/** @var {jQuery} list of elements with errors */
const invalid = this.modal.getRoot().find('[aria-invalid="true"], .error');
// If we found invalid fields, focus on the first one and do not submit via ajax.
if (invalid.length) {
invalid.first().focus();
return false;
}
return true;
}
/**
* Disable buttons during form submission
*/
disableButtons() {
this.modal.getFooter().find('[data-action]').attr('disabled', true);
}
/**
* Enable buttons after form submission (on validation error)
*/
enableButtons() {
this.modal.getFooter().find('[data-action]').removeAttr('disabled');
}
/**
* Submit the form via AJAX call to the core_form_dynamic_form WS
*/
async submitFormAjax() {
// If we found invalid fields, focus on the first one and do not submit via ajax.
if (!this.validateElements()) {
this.trigger(this.events.CLIENT_VALIDATION_ERROR, null, false);
return;
}
this.disableButtons();
// Convert all the form elements values to a serialised string.
const formData = this.modal.getRoot().find('form').serialize();
// Now we can continue...
Ajax.call([{
methodname: 'core_form_dynamic_form',
args: {
formdata: formData,
form: this.config.formClass
}
}])[0]
.then((response) => {
if (!response.submitted) {
// Form was not submitted because validation failed.
const promise = new Promise(
resolve => resolve({html: response.html, js: Fragment.processCollectedJavascript(response.javascript)}));
this.modal.setBodyContent(promise);
this.enableButtons();
this.trigger(this.events.SERVER_VALIDATION_ERROR);
} else {
// Form was submitted properly. Hide the modal and execute callback.
const data = JSON.parse(response.data);
this.notifyResetFormChanges();
const event = this.trigger(this.events.FORM_SUBMITTED, data);
if (!event.defaultPrevented) {
this.modal.hide();
}
}
return null;
})
.catch(exception => this.onSubmitError(exception));
}
/**
* Set the classes for the 'save' button.
*
* @method setSaveButtonClasses
* @param {(String)} value The 'save' button classes.
*/
setSaveButtonClasses(value) {
const button = this.modal.getFooter().find("[data-action='save']");
if (!button) {
throw new Error("Unable to find the 'save' button");
}
button.removeClass().addClass(value);
}
}