let request = require ('request');
let Parser = require ('rss-parser');
let summarizer = require ('node-summary');
const constants = require ('../config/constants');

let parser = new Parser ();

getDataFromRSSFeed = function (url) {
  //let feed = await parser.parseURL(url);
  //console.log(feed.title);
  //feed.items.forEach(item => {
  //  console.log(item.title + ':' + item.link)
  //});
};

getDataFromWPJSON = function (sourceUrl, page = 1, maxPosts = 10) {
  return new Promise ((resolve, reject) => {
    var options = {
      method: 'GET',
      url: `${sourceUrl}/wp-json/wp/v2/posts`,
      qs: {
        page: page,
        per_page: maxPosts,
      },
    };

    request (options, (error, response, body) => {
      if (error) {
        reject (error);
      } else {
        resolve (JSON.parse (body));
      }
    });
  });
};

summarizeText = function (title, text) {
  return new Promise ((resolve, reject) => {
    summarizer.summarize (title, text, (err, summary) => {
      if (err) {
        reject (err);
      } else {
        resolve (summary);
      }
    });
  });
};

module.exports = {
  getAnswerFromWP: function (sourceUrl) {
    //This function will extract needed data from JSON, which we got from getDataFromWPJSON
    //At the moment, it's taking titles and creates answer
    return new Promise ((resolve, reject) => {
      getDataFromWPJSON (sourceUrl)
        .then (rawData => {
          let result = '';
          rawData.forEach (post => {
            result += post.title.rendered + `<break time="${constants.voiceResponseTimings.PAUSE_BETWEEN_TITLES}ms"/> `;
          });
          resolve (result);
        })
        .catch (err => {
          reject (constants.voiceResponseString.ERROR_FETCHING_CONTENT);
        });
    });
  },

  getLatestNewsFromWP: function (sourceUrl, postCount = 10, includeTitle = false) {
    return new Promise ((resolve, reject) => {
      getDataFromWPJSON (sourceUrl, 1, postCount)
        .then (rawData => {
          let result = '';
          let summarizers = [];
          rawData.forEach (post => {
            summarizers.push (
              summarizeText (post.title.rendered, post.content.rendered).then(summary=>{
                result += (includeTitle) ? post.title.rendered : '';
                result += (includeTitle) ? `<break time="${constants.voiceResponseTimings.PAUSE_BETWEEN_TITLE_AND_CONTENT}ms"/>` : '';
                result += summary;
                result += `<break time="${constants.voiceResponseTimings.PAUSE_BETWEEN_NEWS}ms"/>`; 
              }).catch(err=>{
                result += constants.voiceResponseString.ERROR_SUMMARIZING_CONTENT;
                result += `<break time="${constants.voiceResponseTimings.PAUSE_BETWEEN_NEWS}ms"/>`;
              })
            );
          });
          Promise.all(summarizers).then(()=>{
            resolve(result);
          }).catch(()=>{
            reject(result);
          });
        })
        .catch (err => {
          reject (constants.voiceResponseString.ERROR_FETCHING_CONTENT);
        });
    });
  },
};