// (C) Copyright 2015 Moodle Pty Ltd.
//
// 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 { CoreContentLinksHandlerBase } from '@features/contentlinks/classes/base-handler';
import { CoreContentLinksAction } from '@features/contentlinks/services/contentlinks-delegate';
import { CoreCourse } from '@features/course/services/course';
import { CoreNavigator } from '@services/navigator';
import { CoreSitesReadingStrategy } from '@services/sites';
import { CoreDomUtils } from '@services/utils/dom';
import { makeSingleton } from '@singletons';
import { Md5 } from 'ts-md5';
import { AddonModWiki } from '../wiki';
import { AddonModWikiModuleHandlerService } from './module';

/**
 * Handler to treat links to a wiki page or the wiki map.
 */
@Injectable({ providedIn: 'root' })
export class AddonModWikiPageOrMapLinkHandlerService extends CoreContentLinksHandlerBase {

    name = 'AddonModWikiPageOrMapLinkHandler';
    featureName = 'CoreCourseModuleDelegate_AddonModWiki';
    pattern = /\/mod\/wiki\/(view|map)\.php.*([&?]pageid=\d+)/;

    /**
     * @inheritdoc
     */
    getActions(
        siteIds: string[],
        url: string,
        params: Record<string, string>,
    ): CoreContentLinksAction[] | Promise<CoreContentLinksAction[]> {

        return [{
            action: async (siteId: string) => {
                const modal = await CoreDomUtils.showModalLoading();
                const pageId = parseInt(params.pageid, 10);
                const action = url.indexOf('mod/wiki/map.php') != -1 ? 'map' : 'page';

                try {
                    // Get the page data to obtain wikiId, subwikiId, etc.
                    const page = await AddonModWiki.getPageContents(pageId, { siteId });

                    const module = await CoreCourse.getModuleBasicInfoByInstance(
                        page.wikiid,
                        'wiki',
                        { siteId, readingStrategy: CoreSitesReadingStrategy.PREFER_CACHE },
                    );

                    const hash = Md5.hashAsciiStr(JSON.stringify({
                        pageId: page.id,
                        pageTitle: page.title,
                        subwikiId: page.subwikiid,
                        action: action,
                        timestamp: Date.now(),
                    }));

                    await CoreNavigator.navigateToSitePath(
                        AddonModWikiModuleHandlerService.PAGE_NAME + `/${module.course}/${module.id}/page/${hash}`,
                        {
                            params: {
                                module,
                                pageId: page.id,
                                pageTitle: page.title,
                                subwikiId: page.subwikiid,
                                action: action,
                            },
                            siteId,
                        },
                    );
                } catch (error) {
                    CoreDomUtils.showErrorModalDefault(error, 'addon.mod_wiki.errorloadingpage', true);
                } finally {
                    modal.dismiss();
                }
            },
        }];
    }

    /**
     * @inheritdoc
     */
    async isEnabled(siteId: string, url: string, params: Record<string, string>): Promise<boolean> {
        const isMap = url.indexOf('mod/wiki/map.php') != -1;

        if (params.id && !isMap) {
            // ID param is more prioritary than pageid in index page, it's a index URL.
            return false;
        } else if (isMap && params.option !== undefined && params.option != '5') {
            // Map link but the option isn't "Page list", not supported.
            return false;
        }

        return true;
    }

}

export const AddonModWikiPageOrMapLinkHandler = makeSingleton(AddonModWikiPageOrMapLinkHandlerService);
