/* global window document */
/* eslint-disable vars-on-top, no-var, object-shorthand, no-console */
(function(window) {
  var representationsEl = document.getElementById('representations');

  representationsEl.addEventListener('change', function() {
    var selectedIndex = representationsEl.selectedIndex;

    if (!selectedIndex || selectedIndex < 1 || !window.vhs) {
      return;
    }
    var selectedOption = representationsEl.options[representationsEl.selectedIndex];

    if (!selectedOption) {
      return;
    }

    var id = selectedOption.value;

    window.vhs.representations().forEach(function(rep) {
      rep.playlist.disabled = rep.id !== id;
    });

    window.pc.fastQualityChange_();
  });
  var isManifestObjectType = function(url) {
    return (/application\/vnd\.videojs\.vhs\+json/).test(url);
  };
  var hlsOptGroup = document.querySelector('[label="hls"]');
  var dashOptGroup = document.querySelector('[label="dash"]');
  var drmOptGroup = document.querySelector('[label="drm"]');
  var liveOptGroup = document.querySelector('[label="live"]');
  var llliveOptGroup = document.querySelector('[label="low latency live"]');
  var manifestOptGroup = document.querySelector('[label="json manifest object"]');

  var sourceList;
  var hlsDataManifest;
  var dashDataManifest;

  var addSourcesToDom = function() {
    if (!sourceList || !hlsDataManifest || !dashDataManifest) {
      return;
    }

    sourceList.forEach(function(source) {
      var option = document.createElement('option');

      option.innerText = source.name;
      option.value = source.uri;

      if (source.keySystems) {
        option.setAttribute('data-key-systems', JSON.stringify(source.keySystems, null, 2));
      }

      if (source.mimetype) {
        option.setAttribute('data-mimetype', source.mimetype);
      }

      if (source.features.indexOf('low-latency') !== -1) {
        llliveOptGroup.appendChild(option);
      } else if (source.features.indexOf('live') !== -1) {
        liveOptGroup.appendChild(option);
      } else if (source.keySystems) {
        drmOptGroup.appendChild(option);
      } else if (source.mimetype === 'application/x-mpegurl') {
        hlsOptGroup.appendChild(option);
      } else if (source.mimetype === 'application/dash+xml') {
        dashOptGroup.appendChild(option);
      }
    });

    var hlsOption = document.createElement('option');
    var dashOption = document.createElement('option');

    dashOption.innerText = 'Dash Manifest Object Test, does not survive page reload';
    dashOption.value = `data:application/vnd.videojs.vhs+json,${dashDataManifest}`;
    hlsOption.innerText = 'HLS Manifest Object Test, does not survive page reload';
    hlsOption.value = `data:application/vnd.videojs.vhs+json,${hlsDataManifest}`;

    manifestOptGroup.appendChild(hlsOption);
    manifestOptGroup.appendChild(dashOption);
  };

  var sourcesXhr = new window.XMLHttpRequest();

  sourcesXhr.addEventListener('load', function() {
    sourceList = JSON.parse(sourcesXhr.responseText);
    addSourcesToDom();
  });
  sourcesXhr.open('GET', './scripts/sources.json');
  sourcesXhr.send();

  var hlsManifestXhr = new window.XMLHttpRequest();

  hlsManifestXhr.addEventListener('load', function() {
    hlsDataManifest = hlsManifestXhr.responseText;
    addSourcesToDom();

  });
  hlsManifestXhr.open('GET', './scripts/hls-manifest-object.json');
  hlsManifestXhr.send();

  var dashManifestXhr = new window.XMLHttpRequest();

  dashManifestXhr.addEventListener('load', function() {
    dashDataManifest = dashManifestXhr.responseText;
    addSourcesToDom();
  });
  dashManifestXhr.open('GET', './scripts/dash-manifest-object.json');
  dashManifestXhr.send();

  // all relevant elements
  var urlButton = document.getElementById('load-url');
  var sources = document.getElementById('load-source');
  var stateEls = {};

  var getInputValue = function(el) {
    if (el.type === 'url' || el.type === 'text' || el.nodeName.toLowerCase() === 'textarea') {
      if (isManifestObjectType(el.value)) {
        return '';
      }
      return encodeURIComponent(el.value);
    } else if (el.type === 'select-one') {
      return el.options[el.selectedIndex].value;
    } else if (el.type === 'checkbox') {
      return el.checked;
    }

    console.warn('unhandled input type ' + el.type);
    return '';
  };

  var setInputValue = function(el, value) {
    if (el.type === 'url' || el.type === 'text' || el.nodeName.toLowerCase() === 'textarea') {
      el.value = decodeURIComponent(value);
    } else if (el.type === 'select-one') {
      for (var i = 0; i < el.options.length; i++) {
        if (el.options[i].value === value) {
          el.options[i].selected = true;
        }
      }
    } else {
      // get the `value` into a Boolean.
      el.checked = JSON.parse(value);
    }

  };

  var newEvent = function(name) {
    var event;

    if (typeof window.Event === 'function') {
      event = new window.Event(name);
    } else {
      event = document.createEvent('Event');
      event.initEvent(name, true, true);
    }

    return event;
  };

  // taken from video.js
  var getFileExtension = function(path) {
    var splitPathRe;
    var pathParts;

    if (typeof path === 'string') {
      splitPathRe = /^(\/?)([\s\S]*?)((?:\.{1,2}|[^\/]*?)(\.([^\.\/\?]+)))(?:[\/]*|[\?].*)$/i;
      pathParts = splitPathRe.exec(path);

      if (pathParts) {
        return pathParts.pop().toLowerCase();
      }
    }

    return '';
  };

  var saveState = function() {
    var query = '';

    if (!window.history.replaceState) {
      return;
    }

    Object.keys(stateEls).forEach(function(elName) {
      var symbol = query.length ? '&' : '?';

      query += symbol + elName + '=' + getInputValue(stateEls[elName]);
    });

    window.history.replaceState({}, 'vhs demo', query);
  };

  window.URLSearchParams = window.URLSearchParams || function(locationSearch) {
    this.get = function(name) {
      var results = new RegExp('[\?&]' + name + '=([^&#]*)').exec(locationSearch);

      return results ? decodeURIComponent(results[1]) : null;
    };
  };

  // eslint-disable-next-line
  var loadState = function() {
    var params = new window.URLSearchParams(window.location.search);

    return Object.keys(stateEls).reduce(function(acc, elName) {
      acc[elName] = typeof params.get(elName) !== 'object' ? params.get(elName) : getInputValue(stateEls[elName]);
      return acc;
    }, {});
  };

  // eslint-disable-next-line
  var reloadScripts = function(urls, cb) {
    var el = document.getElementById('reload-scripts');

    if (!el) {
      el = document.createElement('div');
      el.id = 'reload-scripts';
      document.body.appendChild(el);
    }

    while (el.firstChild) {
      el.removeChild(el.firstChild);
    }

    var loaded = [];

    var checkDone = function() {
      if (loaded.length === urls.length) {
        cb();
      }
    };

    urls.forEach(function(url) {
      var script = document.createElement('script');

      // scripts marked as defer will be loaded asynchronously but will be executed in the order they are in the DOM
      script.defer = true;
      // dynamically created scripts are async by default unless otherwise specified
      // async scripts are loaded asynchronously but also executed as soon as they are loaded
      // we want to load them in the order they are added therefore we want to turn off async
      script.async = false;
      script.src = url;
      script.onload = function() {
        loaded.push(url);
        checkDone();
      };
      el.appendChild(script);
    });
  };

  var regenerateRepresentations = function() {
    while (representationsEl.firstChild) {
      representationsEl.removeChild(representationsEl.firstChild);
    }

    var selectedIndex;

    window.vhs.representations().forEach(function(rep, i) {
      var option = document.createElement('option');

      option.value = rep.id;
      option.innerText = JSON.stringify({
        id: rep.id,
        videoCodec: rep.codecs.video,
        audioCodec: rep.codecs.audio,
        bandwidth: rep.bandwidth,
        heigth: rep.heigth,
        width: rep.width
      });

      if (window.pc.media().id === rep.id) {
        selectedIndex = i;
      }

      representationsEl.appendChild(option);
    });

    representationsEl.selectedIndex = selectedIndex;
  };

  function getBuffered(buffered) {
    var bufferedText = '';

    if (!buffered) {
      return bufferedText;
    }

    if (buffered.length) {
      bufferedText += buffered.start(0) + ' - ' + buffered.end(0);
    }
    for (var i = 1; i < buffered.length; i++) {
      bufferedText += ', ' + buffered.start(i) + ' - ' + buffered.end(i);
    }
    return bufferedText;
  }

  var setupSegmentMetadata = function(player) {
    // setup segment metadata
    var segmentMetadata = document.querySelector('#segment-metadata');

    player.one('loadedmetadata', function() {
      var tracks = player.textTracks();
      var segmentMetadataTrack;

      for (var i = 0; i < tracks.length; i++) {
        if (tracks[i].label === 'segment-metadata') {
          segmentMetadataTrack = tracks[i];
        }
      }

      while (segmentMetadata.children.length) {
        segmentMetadata.removeChild(segmentMetadata.firstChild);
      }

      if (segmentMetadataTrack) {
        segmentMetadataTrack.addEventListener('cuechange', function() {
          var cues = segmentMetadataTrack.activeCues || [];

          while (segmentMetadata.children.length) {
            segmentMetadata.removeChild(segmentMetadata.firstChild);
          }

          for (var j = 0; j < cues.length; j++) {
            var text = JSON.stringify(JSON.parse(cues[j].text), null, 2);
            var li = document.createElement('li');
            var pre = document.createElement('pre');

            pre.classList.add('border', 'rounded', 'p-2');
            pre.textContent = text;
            li.appendChild(pre);
            segmentMetadata.appendChild(li);
          }
        });
      }
    });
  };

  var setupPlayerStats = function(player) {
    player.on('dispose', () => {
      if (window.statsTimer) {
        window.clearInterval(window.statsTimer);
        window.statsTimer = null;
      }
    });
    var currentTimeStat = document.querySelector('.current-time-stat');
    var bufferedStat = document.querySelector('.buffered-stat');
    var videoBufferedStat = document.querySelector('.video-buffered-stat');
    var audioBufferedStat = document.querySelector('.audio-buffered-stat');
    var seekableStartStat = document.querySelector('.seekable-start-stat');
    var seekableEndStat = document.querySelector('.seekable-end-stat');
    var videoBitrateState = document.querySelector('.video-bitrate-stat');
    var measuredBitrateStat = document.querySelector('.measured-bitrate-stat');
    var videoTimestampOffset = document.querySelector('.video-timestampoffset');
    var audioTimestampOffset = document.querySelector('.audio-timestampoffset');

    player.on('timeupdate', function() {
      currentTimeStat.textContent = player.currentTime().toFixed(1);
    });

    window.statsTimer = window.setInterval(function() {
      var oldStart;
      var oldEnd;
      var seekable = player.seekable();

      if (seekable && seekable.length) {

        oldStart = seekableStartStat.textContent;
        if (seekable.start(0).toFixed(1) !== oldStart) {
          seekableStartStat.textContent = seekable.start(0).toFixed(1);
        }
        oldEnd = seekableEndStat.textContent;
        if (seekable.end(0).toFixed(1) !== oldEnd) {
          seekableEndStat.textContent = seekable.end(0).toFixed(1);
        }
      }

      // buffered
      bufferedStat.textContent = getBuffered(player.buffered());

      // exit early if no VHS
      if (!player.tech(true).vhs) {
        videoBufferedStat.textContent = '';
        audioBufferedStat.textContent = '';
        videoBitrateState.textContent = '';
        measuredBitrateStat.textContent = '';
        videoTimestampOffset.textContent = '';
        audioTimestampOffset.textContent = '';
        return;
      }

      videoBufferedStat.textContent = getBuffered(player.tech(true).vhs.playlistController_.mainSegmentLoader_.sourceUpdater_.videoBuffer &&
        player.tech(true).vhs.playlistController_.mainSegmentLoader_.sourceUpdater_.videoBuffer.buffered);

      // demuxed audio
      var audioBuffer = getBuffered(player.tech(true).vhs.playlistController_.audioSegmentLoader_.sourceUpdater_.audioBuffer &&
        player.tech(true).vhs.playlistController_.audioSegmentLoader_.sourceUpdater_.audioBuffer.buffered);

      // muxed audio
      if (!audioBuffer) {
        audioBuffer = getBuffered(player.tech(true).vhs.playlistController_.mainSegmentLoader_.sourceUpdater_.audioBuffer &&
          player.tech(true).vhs.playlistController_.mainSegmentLoader_.sourceUpdater_.audioBuffer.buffered);
      }
      audioBufferedStat.textContent = audioBuffer;

      if (player.tech(true).vhs.playlistController_.audioSegmentLoader_.sourceUpdater_.audioBuffer) {
        audioTimestampOffset.textContent = player.tech(true).vhs.playlistController_.audioSegmentLoader_.sourceUpdater_.audioBuffer.timestampOffset;

      } else if (player.tech(true).vhs.playlistController_.mainSegmentLoader_.sourceUpdater_.audioBuffer) {
        audioTimestampOffset.textContent = player.tech(true).vhs.playlistController_.mainSegmentLoader_.sourceUpdater_.audioBuffer.timestampOffset;
      }

      if (player.tech(true).vhs.playlistController_.mainSegmentLoader_.sourceUpdater_.videoBuffer) {
        videoTimestampOffset.textContent = player.tech(true).vhs.playlistController_.mainSegmentLoader_.sourceUpdater_.videoBuffer.timestampOffset;
      }

      // bitrates
      var playlist = player.tech_.vhs.playlists.media();

      if (playlist && playlist.attributes && playlist.attributes.BANDWIDTH) {
        videoBitrateState.textContent = (playlist.attributes.BANDWIDTH / 1024).toLocaleString(undefined, {
          maximumFractionDigits: 1
        }) + ' kbps';
      }
      if (player.tech_.vhs.bandwidth) {
        measuredBitrateStat.textContent = (player.tech_.vhs.bandwidth / 1024).toLocaleString(undefined, {
          maximumFractionDigits: 1
        }) + ' kbps';
      }

    }, 100);
  };

  [
    'debug',
    'autoplay',
    'muted',
    'fluid',
    'minified',
    'sync-workers',
    'liveui',
    'llhls',
    'url',
    'type',
    'keysystems',
    'buffer-water',
    'exact-manifest-timings',
    'pixel-diff-selector',
    'network-info',
    'dts-offset',
    'override-native',
    'preload',
    'mirror-source'
  ].forEach(function(name) {
    stateEls[name] = document.getElementById(name);
  });

  window.startDemo = function(cb) {
    var state = loadState();

    Object.keys(state).forEach(function(elName) {
      setInputValue(stateEls[elName], state[elName]);
    });

    Array.prototype.forEach.call(sources.options, function(s, i) {
      if (s.value === state.url) {
        sources.selectedIndex = i;
      }
    });

    stateEls.fluid.addEventListener('change', function(event) {
      saveState();
      if (event.target.checked) {
        window['player-fixture'].style.aspectRatio = '16/9';
        window['player-fixture'].style.minHeight = 'initial';
      } else {
        window['player-fixture'].style.aspectRatio = '';
        window['player-fixture'].style.minHeight = '250px';
      }
      window.player.fluid(event.target.checked);
    });

    stateEls.muted.addEventListener('change', function(event) {
      saveState();
      window.player.muted(event.target.checked);
    });

    stateEls.autoplay.addEventListener('change', function(event) {
      saveState();
      window.player.autoplay(event.target.checked);
    });

    // stateEls that reload the player and scripts
    [
      'mirror-source',
      'sync-workers',
      'preload',
      'llhls',
      'buffer-water',
      'override-native',
      'liveui',
      'pixel-diff-selector',
      'network-info',
      'dts-offset',
      'exact-manifest-timings'
    ].forEach(function(name) {
      stateEls[name].addEventListener('change', function(event) {
        saveState();

        stateEls.minified.dispatchEvent(newEvent('change'));
      });
    });

    [
      'llhls'
    ].forEach(function(name) {
      stateEls[name].checked = true;
    });

    [
      'exact-manifest-timings',
      'pixel-diff-selector',
      'buffer-water'
    ].forEach(function(name) {
      stateEls[name].checked = false;
    });

    stateEls.debug.addEventListener('change', function(event) {
      saveState();
      window.videojs.log.level(event.target.checked ? 'debug' : 'info');
    });

    stateEls.minified.addEventListener('change', function(event) {
      var urls = [
        'node_modules/video.js/dist/alt/video.core',
        'node_modules/videojs-contrib-eme/dist/videojs-contrib-eme',
        'node_modules/videojs-contrib-quality-levels/dist/videojs-contrib-quality-levels',
        'node_modules/videojs-http-source-selector/dist/videojs-http-source-selector'
      ].map(function(url) {
        return url + (event.target.checked ? '.min' : '') + '.js';
      });

      if (stateEls['sync-workers'].checked) {
        urls.push('dist/videojs-http-streaming-sync-workers.js');
      } else {
        urls.push('dist/videojs-http-streaming' + (event.target.checked ? '.min' : '') + '.js');
      }

      saveState();

      if (window.player) {
        window.player.dispose();
        delete window.player;
      }
      if (window.videojs) {
        delete window.videojs;
      }

      reloadScripts(urls, function() {
        var player;
        var fixture = document.getElementById('player-fixture');
        var videoEl = document.createElement('video-js');

        videoEl.setAttribute('controls', '');
        videoEl.setAttribute('preload', stateEls.preload.options[stateEls.preload.selectedIndex].value || 'auto');
        videoEl.className = 'vjs-default-skin';
        fixture.appendChild(videoEl);

        var mirrorSource = getInputValue(stateEls['mirror-source']);

        player = window.player = window.videojs(videoEl, {
          plugins: {
            httpSourceSelector: {
              default: 'auto'
            }
          },
          liveui: stateEls.liveui.checked,
          enableSourceset: mirrorSource,
          html5: {
            vhs: {
              overrideNative: getInputValue(stateEls['override-native']),
              bufferBasedABR: getInputValue(stateEls['buffer-water']),
              llhls: getInputValue(stateEls.llhls),
              exactManifestTimings: getInputValue(stateEls['exact-manifest-timings']),
              leastPixelDiffSelector: getInputValue(stateEls['pixel-diff-selector']),
              useNetworkInformationApi: getInputValue(stateEls['network-info']),
              useDtsForTimestampOffset: getInputValue(stateEls['dts-offset'])
            }
          }
        });

        setupPlayerStats(player);
        setupSegmentMetadata(player);

        // save player muted state interation
        player.on('volumechange', function() {
          if (stateEls.muted.checked !== player.muted()) {
            stateEls.muted.checked = player.muted();
            saveState();
          }
        });

        player.on('sourceset', function() {
          var source = player.currentSource();

          if (source.keySystems) {
            var copy = JSON.parse(JSON.stringify(source.keySystems));

            // have to delete pssh as it will often make keySystems too big
            // for a uri
            Object.keys(copy).forEach(function(key) {
              if (copy[key].hasOwnProperty('pssh')) {
                delete copy[key].pssh;
              }
            });

            stateEls.keysystems.value = JSON.stringify(copy, null, 2);
          }

          if (source.src) {
            stateEls.url.value = encodeURI(source.src);
          }

          if (source.type) {
            stateEls.type.value = source.type;
          }

          saveState();
        });

        player.width(640);
        player.height(264);

        // configure videojs-contrib-eme
        player.eme();

        stateEls.debug.dispatchEvent(newEvent('change'));
        stateEls.muted.dispatchEvent(newEvent('change'));
        stateEls.fluid.dispatchEvent(newEvent('change'));
        stateEls.autoplay.dispatchEvent(newEvent('change'));

        // run the load url handler for the intial source
        if (stateEls.url.value) {
          urlButton.dispatchEvent(newEvent('click'));
        } else {
          sources.dispatchEvent(newEvent('change'));
        }
        player.on('loadedmetadata', function() {
          if (player.tech_.vhs) {
            window.vhs = player.tech_.vhs;
            window.pc = player.tech_.vhs.playlistController_;
            window.pc.mainPlaylistLoader_.on('mediachange', regenerateRepresentations);
            regenerateRepresentations();

          } else {
            window.vhs = null;
            window.pc = null;
          }
        });
        cb(player);
      });
    });

    var urlButtonClick = function(event) {
      var ext;
      var type = stateEls.type.value;

      // reset type if it's a manifest object's type
      if (type === 'application/vnd.videojs.vhs+json') {
        type = '';
      }

      if (isManifestObjectType(stateEls.url.value)) {
        type = 'application/vnd.videojs.vhs+json';
      }

      if (!type.trim()) {
        ext = getFileExtension(stateEls.url.value);

        if (ext === 'mpd') {
          type = 'application/dash+xml';
        } else if (ext === 'm3u8') {
          type = 'application/x-mpegURL';
        }
      }

      saveState();

      var source = {
        src: stateEls.url.value,
        type: type
      };

      if (stateEls.keysystems.value) {
        source.keySystems = JSON.parse(stateEls.keysystems.value);
      }

      sources.selectedIndex = -1;

      Array.prototype.forEach.call(sources.options, function(s, i) {
        if (s.value === stateEls.url.value) {
          sources.selectedIndex = i;
        }
      });

      window.player.src(source);
    };

    urlButton.addEventListener('click', urlButtonClick);
    urlButton.addEventListener('tap', urlButtonClick);

    sources.addEventListener('change', function(event) {
      var selectedOption = sources.options[sources.selectedIndex];

      if (!selectedOption) {
        return;
      }
      var src = selectedOption.value;

      stateEls.url.value = src;
      stateEls.type.value = selectedOption.getAttribute('data-mimetype');
      stateEls.keysystems.value = selectedOption.getAttribute('data-key-systems');

      urlButton.dispatchEvent(newEvent('click'));
    });

    stateEls.url.addEventListener('keyup', function(event) {
      if (event.key === 'Enter') {
        urlButton.click();
      }
    });
    stateEls.url.addEventListener('input', function(event) {
      if (stateEls.type.value.length) {
        stateEls.type.value = '';
      }
    });
    stateEls.type.addEventListener('keyup', function(event) {
      if (event.key === 'Enter') {
        urlButton.click();
      }
    });

    // run the change handler for the first time
    stateEls.minified.dispatchEvent(newEvent('change'));
  };
}(window));