/* 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.mpc.smoothQualityChange_();
  });
  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"]');

  // get the sources list squared away
  var xhr = new window.XMLHttpRequest();

  xhr.addEventListener('load', function() {
    var sources = JSON.parse(xhr.responseText);

    sources.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);
      }
    });
  });
  xhr.open('GET', './scripts/sources.json');
  xhr.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') {
      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.mpc.media().id === rep.id) {
        selectedIndex = i;
      }

      representationsEl.appendChild(option);
    });

    representationsEl.selectedIndex = selectedIndex;
  };

  [
    'debug',
    'autoplay',
    'muted',
    'minified',
    'sync-workers',
    'liveui',
    'partial',
    'url',
    'type',
    'keysystems',
    'buffer-water',
    '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.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['mirror-source'].addEventListener('change', function(event) {
      saveState();

      // reload the player and scripts
      stateEls.minified.dispatchEvent(newEvent('change'));
    });

    stateEls['sync-workers'].addEventListener('change', function(event) {
      saveState();

      // reload the player and scripts
      stateEls.minified.dispatchEvent(newEvent('change'));
    });

    stateEls.preload.addEventListener('change', function(event) {
      saveState();
      // reload the player and scripts
      stateEls.minified.dispatchEvent(newEvent('change'));
    });

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

    stateEls.partial.addEventListener('change', function(event) {
      saveState();

      // reload the player and scripts
      stateEls.minified.dispatchEvent(newEvent('change'));
    });

    stateEls['buffer-water'].addEventListener('change', function(event) {
      saveState();

      // reload the player and scripts
      stateEls.minified.dispatchEvent(newEvent('change'));
    });

    stateEls['override-native'].addEventListener('change', function(event) {
      saveState();

      // reload the player and scripts
      stateEls.minified.dispatchEvent(newEvent('change'));
    });

    stateEls.liveui.addEventListener('change', function(event) {
      saveState();

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

    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']),
              handlePartialData: getInputValue(stateEls.partial),
              experimentalBufferBasedABR: getInputValue(stateEls['buffer-water'])
            }
          }
        });

        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 = 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.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.mpc = player.tech_.vhs.masterPlaylistController_;
            window.mpc.masterPlaylistLoader_.on('mediachange', regenerateRepresentations);
            regenerateRepresentations();

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

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

      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));