import * as path from 'path';
import * as fs from 'fs-extra';
import * as Handlebars from 'handlebars';
import { logger } from '../../logger';
import { Configuration } from '../configuration';
import { ConfigurationInterface } from '../interfaces/configuration.interface';
import { FileEngine } from './file.engine';

const lunr: any = require('lunr');
const cheerio: any = require('cheerio');
const Entities: any = require('html-entities').AllHtmlEntities;
const Html = new Entities();

export class SearchEngine {
    public searchIndex: any;
    public documentsStore: Object = {};
    public indexSize: number;

    constructor(
        private configuration: ConfigurationInterface,
        private fileEngine: FileEngine = new FileEngine()) { }

    private getSearchIndex() {
        if (!this.searchIndex) {
            this.searchIndex = lunr(function () {
                this.ref('url');
                this.field('title', { boost: 10 });
                this.field('body');
            });
        }
        return this.searchIndex;
    }

    public indexPage(page) {
        let text;
        let $ = cheerio.load(page.rawData);

        text = $('.content').html();
        text = Html.decode(text);
        text = text.replace(/(<([^>]+)>)/ig, '');

        page.url = page.url.replace(this.configuration.mainData.output, '');

        let doc = {
            url: page.url,
            title: page.infos.context + ' - ' + page.infos.name,
            body: text
        };

        if (!this.documentsStore.hasOwnProperty(doc.url)) {
            this.documentsStore[doc.url] = doc;
            this.getSearchIndex().add(doc);
        }
    }

    public generateSearchIndexJson(outputFolder: string): Promise<void> {
        return this.fileEngine.get(__dirname + '/../src/templates/partials/search-index.hbs').then(data => {
            let template: any = Handlebars.compile(data);
            let result = template({
                index: JSON.stringify(this.getSearchIndex()),
                store: JSON.stringify(this.documentsStore)
            });
            let testOutputDir = outputFolder.match(process.cwd());
            if (!testOutputDir) {
                outputFolder = outputFolder.replace(process.cwd(), '');
            }
            return this.fileEngine.write(outputFolder + path.sep + '/js/search/search_index.js', result)
                .catch(err => {
                    logger.error('Error during search index file generation ', err);
                    return Promise.reject(err);
                });
        }, err => Promise.reject('Error during search index generation'));
    }
}