// (C) Copyright 2015 Martin Dougiamas
//
// 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
//
// http://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 { Injectable } from '@angular/core';
import { TranslateService } from '@ngx-translate/core';
import { CoreSitesProvider } from '../../../providers/sites';
import { CoreDomUtilsProvider } from '../../../providers/utils/dom';
import { CoreContentLinksHandlerBase } from '../../contentlinks/classes/base-handler';
import { CoreContentLinksAction } from '../../contentlinks/providers/delegate';
import { CoreLoginHelperProvider } from '../../login/providers/helper';
import { CoreCourseProvider } from '../../course/providers/course';
import { CoreCoursesProvider } from './courses';
/**
* Handler to treat links to course view or enrol (except site home).
*/
@Injectable()
export class CoreCoursesCourseLinkHandler extends CoreContentLinksHandlerBase {
name = 'CoreCoursesCourseLinkHandler';
pattern = /((\/enrol\/index\.php)|(\/course\/enrol\.php)|(\/course\/view\.php)).*([\?\&]id=\d+)/;
protected waitStart = 0;
constructor(private sitesProvider: CoreSitesProvider, private coursesProvider: CoreCoursesProvider,
private loginHelper: CoreLoginHelperProvider, private domUtils: CoreDomUtilsProvider,
private translate: TranslateService, private courseProvider: CoreCourseProvider) {
super();
}
/**
* Get the list of actions for a link (url).
*
* @param {string[]} siteIds List of sites the URL belongs to.
* @param {string} url The URL to treat.
* @param {any} params The params of the URL. E.g. 'mysite.com?id=1' -> {id: 1}
* @param {number} [courseId] Course ID related to the URL. Optional but recommended.
* @return {CoreContentLinksAction[]|Promise<CoreContentLinksAction[]>} List of (or promise resolved with list of) actions.
*/
getActions(siteIds: string[], url: string, params: any, courseId?: number):
CoreContentLinksAction[] | Promise<CoreContentLinksAction[]> {
courseId = parseInt(params.id, 10);
const sectionId = params.sectionid ? parseInt(params.sectionid, 10) : null,
sectionNumber = typeof params.section != 'undefined' ? parseInt(params.section, 10) : NaN,
pageParams: any = {
course: { id: courseId },
sectionId: sectionId || null
};
if (!isNaN(sectionNumber)) {
pageParams.sectionNumber = sectionNumber;
}
return [{
action: (siteId, navCtrl?): void => {
siteId = siteId || this.sitesProvider.getCurrentSiteId();
if (siteId == this.sitesProvider.getCurrentSiteId()) {
this.actionEnrol(courseId, url, pageParams).catch(() => {
// Ignore errors.
});
} else {
// Use redirect to make the course the new history root (to avoid "loops" in history).
this.loginHelper.redirect('CoreCourseSectionPage', pageParams, siteId);
}
}
}];
}
/**
* Check if the handler is enabled for a certain site (site + user) and a URL.
* If not defined, defaults to true.
*
* @param {string} siteId The site ID.
* @param {string} url The URL to treat.
* @param {any} params The params of the URL. E.g. 'mysite.com?id=1' -> {id: 1}
* @param {number} [courseId] Course ID related to the URL. Optional but recommended.
* @return {boolean|Promise<boolean>} Whether the handler is enabled for the URL and site.
*/
isEnabled(siteId: string, url: string, params: any, courseId?: number): boolean | Promise<boolean> {
courseId = parseInt(params.id, 10);
if (!courseId) {
return false;
}
// Get the course id of Site Home.
return this.sitesProvider.getSiteHomeId(siteId).then((siteHomeId) => {
return courseId != siteHomeId;
});
}
/**
* Action to perform when an enrol link is clicked.
*
* @param {number} courseId Course ID.
* @param {string} url Treated URL.
* @param {any} pageParams Params to send to the new page.
* @return {Promise<any>} Promise resolved when done.
*/
protected actionEnrol(courseId: number, url: string, pageParams: any): Promise<any> {
const modal = this.domUtils.showModalLoading(),
isEnrolUrl = !!url.match(/(\/enrol\/index\.php)|(\/course\/enrol\.php)/);
// Check if user is enrolled in the course.
return this.coursesProvider.getUserCourse(courseId).catch(() => {
// User is not enrolled in the course. Check if can self enrol.
return this.canSelfEnrol(courseId).then(() => {
modal.dismiss();
// The user can self enrol. If it's not a enrolment URL we'll ask for confirmation.
const promise = isEnrolUrl ? Promise.resolve() :
this.domUtils.showConfirm(this.translate.instant('core.courses.confirmselfenrol'));
return promise.then(() => {
// Enrol URL or user confirmed.
return this.selfEnrol(courseId).catch((error) => {
if (error) {
this.domUtils.showErrorModal(error);
}
return Promise.reject(null);
});
}, () => {
// User cancelled. Check if the user can view the course contents (guest access or similar).
return this.courseProvider.getSections(courseId, false, true);
});
}, (error) => {
// Can't self enrol. Check if the user can view the course contents (guest access or similar).
return this.courseProvider.getSections(courseId, false, true).catch(() => {
// Error. Show error message and allow the user to open the link in browser.
modal.dismiss();
if (error) {
error = error.message || error.error || error.content || error.body || error;
}
if (!error) {
error = this.translate.instant('core.courses.notenroled');
}
const body = this.translate.instant('core.twoparagraphs',
{ p1: error, p2: this.translate.instant('core.confirmopeninbrowser') });
this.domUtils.showConfirm(body).then(() => {
this.sitesProvider.getCurrentSite().openInBrowserWithAutoLogin(url);
}).catch(() => {
// User cancelled.
});
return Promise.reject(null);
});
});
}).then(() => {
modal.dismiss();
// Use redirect to make the course the new history root (to avoid "loops" in history).
this.loginHelper.redirect('CoreCourseSectionPage', pageParams, this.sitesProvider.getCurrentSiteId());
});
}
/**
* Check if a user can be "automatically" self enrolled in a course.
*
* @param {number} courseId Course ID.
* @return {Promise<any>} Promise resolved if user can be enrolled in a course, rejected otherwise.
*/
protected canSelfEnrol(courseId: number): Promise<any> {
// Check that the course has self enrolment enabled.
return this.coursesProvider.getCourseEnrolmentMethods(courseId).then((methods) => {
let isSelfEnrolEnabled = false,
instances = 0;
methods.forEach((method) => {
if (method.type == 'self' && method.status) {
isSelfEnrolEnabled = true;
instances++;
}
});
if (!isSelfEnrolEnabled || instances != 1) {
// Self enrol not enabled or more than one instance.
return Promise.reject(null);
}
});
}
/**
* Try to self enrol a user in a course.
*
* @param {number} courseId Course ID.
* @param {string} [password] Password.
* @return {Promise<any>} Promise resolved when the user is enrolled, rejected otherwise.
*/
protected selfEnrol(courseId: number, password?: string): Promise<any> {
const modal = this.domUtils.showModalLoading();
return this.coursesProvider.selfEnrol(courseId, password).then(() => {
// Success self enrolling the user, invalidate the courses list.
return this.coursesProvider.invalidateUserCourses().catch(() => {
// Ignore errors.
}).then(() => {
// Sometimes the list of enrolled courses takes a while to be updated. Wait for it.
return this.waitForEnrolled(courseId, true).finally(() => {
modal.dismiss();
});
});
}).catch((error) => {
modal.dismiss();
if (error && error.code === CoreCoursesProvider.ENROL_INVALID_KEY) {
// Invalid password. Allow the user to input password.
const title = this.translate.instant('core.courses.selfenrolment'),
body = ' ', // Empty message.
placeholder = this.translate.instant('core.courses.password');
if (typeof password != 'undefined') {
// The user attempted a password. Show an error message.
this.domUtils.showErrorModal(error.message);
}
return this.domUtils.showPrompt(body, title, placeholder).then((password) => {
return this.selfEnrol(courseId, password);
});
} else {
return Promise.reject(error);
}
});
}
/**
* Wait for the user to be enrolled in a course.
*
* @param {number} courseId The course ID.
* @param {boolean} first If it's the first call (true) or it's a recursive call (false).
* @return {Promise<any>} Promise resolved when enrolled or timeout.
*/
protected waitForEnrolled(courseId: number, first?: boolean): Promise<any> {
if (first) {
this.waitStart = Date.now();
}
// Check if user is enrolled in the course.
return this.coursesProvider.invalidateUserCourses().catch(() => {
// Ignore errors.
}).then(() => {
return this.coursesProvider.getUserCourse(courseId);
}).catch(() => {
// Not enrolled, wait a bit and try again.
if (Date.now() - this.waitStart > 60000) {
// Max time reached, stop.
return;
}
return new Promise((resolve, reject): void => {
setTimeout(() => {
this.waitForEnrolled(courseId).then(resolve);
}, 5000);
});
});
}
}