'use strict';

// modules
const express = require('express');
const http = require('http');
const https = require('https');
const parse = require('node-html-parser').parse;

// HTTP status codes by name
const codes = require('./http-codes');

const routerHandling = require('../middleware/router-handling');

/**
 * getHtml:  REST get request returning HTML page response
 * @param {object} options: http options object
 * @param {function} onResult: callback to pass the results JSON object(s) back
 */
const getHtml = (options, onResult) => {
  let port = (options.port === 443) ? https : http;
  let req = port.request(options, (res) => {
    let output = '';
    res.setEncoding('utf8');

    res.on('data', (chunk) => {
      output += chunk;
    });

    res.on('end', () => {
      if (res.statusCode === 301) { // follow redirect
        const location = res.headers.location;
        const baseUrl = ((options.port === 443) ? 'https' : 'http') + '://' + options.host;
        options.path = location.replace(baseUrl, '');
        getHtml(options, (status, redirectData) => {
          onResult(status, redirectData);
        });
      } else {
        onResult(res.statusCode, output);
      }
    });

    res.on('error', (err) => {
      onResult(500, err);
    });
  });
  req.end();
};

const defaulUserReqOptions = {
  host: 'opt4.net',
  port: 443,
  path: '/dashboard/index.php?user/',
  method: 'GET',
};

const slotting = new express.Router();

// routes **********************
slotting.route('/user/:id')
        .get((req, res, next) => {
          const userId = req.params.id;
          const options = Object.assign({}, defaulUserReqOptions);
          options.path = options.path.concat(userId);

          getHtml(options, (status, targetRes) => {
            if (status !== codes.success) {
              const err = new Error('Can not resolve user from remote service');
              err.status = codes.notfound;
              return next(err);
            }

            const root = parse(targetRes);
            const userNameEl = root.querySelector('.contentTitle');
            let user = {
              name: userNameEl.childNodes[0].rawText.trim(),
            };

            res.locals.items = user;
            res.locals.processed = true;
            return next();
          });
        })

        .all(
          routerHandling.httpMethodNotAllowed
        );

// this middleware function can be used, if you like or remove it
// it looks for object(s) in res.locals.items and if they exist, they are send to the client as json
slotting.use(routerHandling.emptyResponse);

module.exports = slotting;