var express = require('express');
var YoutubeMp3Downloader = require("youtube-mp3-downloader");
var fs = require('fs');
var path = require('path');
var urlParse = require("body-parser");
var id3 = require('node-id3');

var router = express.Router();
router.use(function(req, res, next) {
  res.header("Access-Control-Allow-Origin", "*"); // update to match the domain you will make the request from
  res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");
  next();
});

var YD = new YoutubeMp3Downloader({
  "ffmpegPath": path.join(__dirname + "/../bin/ffmpeg"),
  "outputPath": path.join(__dirname + "/../music"),
  "youtubeVideoQuality": "highest",
  "queueParallelism": 1,
  "progressTimeout": 2000
});
const rootdir = path.join(__dirname, '/../');

/* GET home page. */
router.get('/', (_req, res, _next) => {
  res.render('index', { title: 'Express' });
});

// Download route to download youtube video's
router.get('/download', (req, res, _next) => {
  YD.download(req.query.url);

  YD.on('finished', (err, data) => {
    if (err) {
      res.json({ result: err });
    } else {
      res.json({ result: data });
    }
  });
});

function dbGet(type, id) {
  let db = {
      song: require(rootdir + 'database/songs.json'),
      album: require(rootdir + "database/albums.json"),
      artist: require(rootdir + "database/artists.json")
  };
  let result; 

  if (id === 'all') {
      result = db[type];
  } else {
      id = parseInt(id);
      db[type].forEach(element => {
        if (id == element.id) {
          result = element;
        }
      });
  }

  return result;
}

router.get('/get/:type/:id', (req, res, _next) => {
  // Get variables from url
  const type = req.params.type;
  const id = req.params.id;

  // Check if all info is requested
  if (id === 'all') {
    res.json({ result: dbGet(type, id) });
  } else {
    // Split arguments and reset result
    const arg = id.split(",");
    resultArray = [];

    // TODO
    // OK, for some reason this script works absolutely fine when run the fist time,
    // However, if you run any other get url or refresh the page it will either throw a circulation error or return a bunch of null values
    // I have no idea what is causing this but i am absolutely fucking done with it right now
    // If you read this and you know how to fix it, please change it

    // For each array in argument, make object in resultArray
    for (let index = 0; index < arg.length; index++) {
      resultArray[index] = dbGet(type, arg[index]);
      
      // Add song info if id is given
      if (typeof resultArray[index].song !== 'undefined') { 
        for (let song = 0; song < resultArray[index].song.length; song++) {
          resultArray[index].song[song] = dbGet('song', resultArray[index].song[song]);
        }
      }

      // Add artist info if id is given
      if (typeof resultArray[index].artist !== 'undefined') { 
        for (let artist = 0; artist < resultArray[index].artist.length; artist++) {
          resultArray[index].artist[artist] = dbGet('artist', resultArray[index].artist[artist]);
        }
      } 


      // Add album info if id is given
      if (typeof resultArray[index].album !== 'undefined') { 
        for (let album = 0; album < resultArray[index].album.length; album++) {
          resultArray[index].album[album] = dbGet('album', resultArray[index].album[album]);
        }
      }  

    }
    // Print result
    res.json({ result: resultArray });
  }
});

// Play route to stream track
router.get('/play/:track', (req, res, _next) => {
  var key = req.params.track;

  var music = rootdir + "music/" + key + ".mp3";

  var stat = fs.statSync(music);
  range = req.headers.range;
  var readStream;

  if (range !== undefined) {
    var parts = range.replace(/bytes=/, "").split("-");

    var partial_start = parts[0];
    var partial_end = parts[1];

    if (
      (isNaN(partial_start) && partial_start.length > 1) ||
      (isNaN(partial_end) && partial_end.length > 1)
    ) {
      return res.sendStatus(500); //ERR_INCOMPLETE_CHUNKED_ENCODING
    }

    var start = parseInt(partial_start, 10);
    var end = partial_end ? parseInt(partial_end, 10) : stat.size - 1;
    var content_length = end - start + 1;

    res.status(206).header({
      "Content-Type": "audio/mpeg",
      "Content-Length": content_length,
      "Content-Range": "bytes " + start + "-" + end + "/" + stat.size
    });

    readStream = fs.createReadStream(music, { start: start, end: end });
  } else {
    res.header({
      "Content-Type": "audio/mpeg",
      "Content-Length": stat.size
    });
    readStream = fs.createReadStream(music);
  }
  readStream.pipe(res);
});

// Image route to get album image
router.get('/image/:path', (req, res, _next) => {
  const path = '/music/' + req.params.path

  res.sendFile(path, { root: rootdir });
});

// Search route to search for a query in the db
router.get('/search/:query', (req, res, _next) => {
  const query = req.params.query;
  let result = [];

  fs.readdir(rootdir + 'database/', (err, files) => {
    files.forEach(file => {

      const content = require(rootdir + 'database/' + file);

      content.forEach(element => {
        if (element.name.match(query)) {
          element.foundIn = file;
          result.push(element);
        }
      });

    });

    res.json({result: result});
  });
});

router.use(urlParse.urlencoded({extended : true}));
// Analyse route to scan .mp3 ID3 tags
router.get('/analyse/*', (req, res, _next) => {
  let file = '/' + req.params[0];
  if (fs.existsSync(file)) {
    var result = id3.read(file);
    if (result.image.imageBuffer) {
      result.image.base64 = result.image.imageBuffer.toString('base64');
    }
  } else {
    var result = `File ${file} not found`;
  }
  res.json({ result: result });
});

module.exports = router;