/*
This file is part of FreeTube.

FreeTube is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

FreeTube is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with FreeTube.  If not, see <http://www.gnu.org/licenses/>.
*/



/**
 * Perform a search using the YouTube API. The search query is grabbed from the #search element.
 *
 * @param {string} nextPageToken - Optional: The page token to be inlcuded in the search.
 *
 * @return {Void}
 */
function search(nextPageToken = '') {
  const query = document.getElementById('search').value;

  if (query === '') {
    return;
  }

  if (nextPageToken === '') {
    clearMainContainer();
    startLoadingAnimation();
  } else {
    console.log(nextPageToken);
    showToast('Fetching results.  Please wait...');
  }

  youtubeAPI('search', {
    q: query,
    part: 'id',
    pageToken: nextPageToken,
    maxResults: 25,
  }, function(data) {
    console.log(data);

    let channels = data.items.filter((item) => {
      if (item.id.kind === 'youtube#channel') {
        return true;
      }
    });

    let playlists = data.items.filter((item) => {
      if (item.id.kind === 'youtube#playlist') {
        return true;
      }
    });

    let videos = data.items.filter((item) => {
      if (item.id.kind === 'youtube#video') {
        return true;
      }
    });

    console.log(channels);
    console.log(typeof(channels));
    console.log(playlists);

    if(playlists.length > 0){
      displayPlaylists(playlists);
    }

    if(channels.length > 0){
      displayChannels(channels);
    }

    let grabDuration = getDuration(videos);

    grabDuration.then((videoList) => {
      console.log(videoList);
      videoList.items.forEach(displayVideo);
    });

    if (nextPageToken === '') {
      createVideoListContainer('Search results:');
      stopLoadingAnimation();
    }
    addNextPage(data.nextPageToken);
  })
}

/**
 * Grab the duration of the videos
 *
 * @param {array} data - An array of videos to get the duration from
 *
 * @return {promise} - The list of videos with the duration included.
 */
function getDuration(data) {
  return new Promise((resolve, reject) => {
    let videoIdList = '';

    for (let i = 0; i < data.length; i++) {
      if (videoIdList === '') {
        if (typeof(data[i]['id']) === 'string') {
          videoIdList = data[i]['id'];
        } else {
          videoIdList = data[i]['id']['videoId'];
        }
      } else {
        if (typeof(data[i]['id']) === 'string') {
          videoIdList = videoIdList + ', ' + data[i]['id'];
        } else {
          videoIdList = videoIdList + ', ' + data[i]['id']['videoId'];
        }
      }
    }

    youtubeAPI('videos', {
      part: 'snippet, contentDetails',
      id: videoIdList
    }, (data) => {
      resolve(data);
    });
  });
}

/**
 * Display a video on the page.  Function is typically contained in a loop.
 *
 * @param {video} video - The video ID of the video to be displayed.
 * @param {string} listType - Optional: Specifies the list type of the video
 *                            Used for displaying the remove icon for history and saved videos.
 *
 * @return {Void}
 */
function displayVideo(video, listType = '') {
  const videoSnippet = video.snippet;

  const videoDuration = parseVideoDuration(video.contentDetails.duration);
  //const videoDuration = '00:00';

  // Grab the published date for the video and convert to a user readable state.
  const dateString = new Date(videoSnippet.publishedAt);
  const publishedDate = dateFormat(dateString, "mmm dS, yyyy");

  const searchMenu = $('#videoListContainer').html();
  const videoId = video.id;

  // Include a remove icon in the list if the application is displaying the history list or saved videos.
  const deleteHtml = () => {
    switch (listType) {
      case 'saved':
        return `<li onclick="removeSavedVideo('${videoId}'); showSavedVideos();">Remove Saved Video</li>`;
      case 'history':
        return `<li onclick="removeFromHistory('${videoId}'); showHistory();">Remove From History</li>`;
    }
  };

  // Includes text if the video is live.
  const liveText = (videoSnippet.liveBroadcastContent === 'live') ? 'LIVE NOW' : '';
  const videoListTemplate = require('./templates/videoList.html');

  mustache.parse(videoListTemplate);
  const rendered = mustache.render(videoListTemplate, {
    videoId: videoId,
    videoThumbnail: videoSnippet.thumbnails.medium.url,
    videoTitle: videoSnippet.title,
    channelName: videoSnippet.channelTitle,
    videoDescription: videoSnippet.description,
    channelId: videoSnippet.channelId,
    videoDuration: videoDuration,
    publishedDate: publishedDate,
    liveText: liveText,
    deleteHtml: deleteHtml,
  });

  // Apply the render to the page
  const nextButton = document.getElementById('getNextPage');
  if (nextButton === null) {
    $('#videoListContainer').append(rendered);
  } else {
    $(rendered).insertBefore('#getNextPage');
  }
}

function displayChannels(channels) {
  let channelIds;

  channels.forEach((channel) => {
    if (typeof(channelIds) === 'undefined') {
      channelIds = channel.id.channelId;
    } else {
      channelIds = channelIds + ',' + channel.id.channelId;
    }
  });

  console.log(channelIds);

  youtubeAPI('channels', {
    part: 'snippet,statistics',
    id: channelIds,
  }, function(data) {
    console.log(data);
    let items = data['items'].reverse();
    const videoListTemplate = require('./templates/channelList.html');

    console.log(items);

    items.forEach((item) => {
      mustache.parse(videoListTemplate);
      let rendered = mustache.render(videoListTemplate, {
        channelId: item.id,
        channelThumbnail: item.snippet.thumbnails.medium.url,
        channelName: item.snippet.title,
        channelDescription: item.snippet.description,
        subscriberCount: item.statistics.subscriberCount,
        videoCount: item.statistics.videoCount,
      });

      $(rendered).insertBefore('#getNextPage');
    });
  });
}

function displayPlaylists(playlists) {
  let playlistIds;

  playlists.forEach((playlist) => {
    if (typeof(playlistIds) === 'undefined') {
      playlistIds = playlist.id.playlistId;
    } else {
      playlistIds = playlistIds + ',' + playlist.id.playlistId;
    }
  });

  console.log(playlistIds);

  youtubeAPI('playlists', {
    part: 'snippet,contentDetails',
    id: playlistIds,
  }, function(data) {
    console.log(data);
    let items = data['items'].reverse();
    const playlistListTemplate = require('./templates/playlistList.html');

    console.log(items);

    items.forEach((item) => {
      let dateString = new Date(item.snippet.publishedAt);
      let publishedDate = dateFormat(dateString, "mmm dS, yyyy");

      mustache.parse(playlistListTemplate);
      let rendered = mustache.render(playlistListTemplate, {
        channelId: item.snippet.channelId,
        channelName: item.snippet.channelTitle,
        playlistThumbnail: item.snippet.thumbnails.medium.url,
        playlistTitle: item.snippet.title,
        playlistDescription: item.snippet.description,
        videoCount: item.contentDetails.itemCount,
        publishedDate: publishedDate,
      });

      $(rendered).insertBefore('#getNextPage');
    });
  });
}

/**
 * Changes the page token to the next page button during a video search.
 *
 * @param {string} nextPageToken - The page token to replace the button function.
 *
 * @return {Void}
 */
function addNextPage(nextPageToken) {
  let oldFetchButton = document.getElementById('getNextPage');

  // Creates the element if it doesn't exist.
  if (oldFetchButton === null) {
    let fetchButton = document.createElement('div');
    fetchButton.id = 'getNextPage';
    fetchButton.innerHTML = '<i class="fas fa-search"></i> Fetch more results...';

    $('#videoListContainer').append(fetchButton);
  }

  // Update the on click method of the button.
  $(document).off('click', '#getNextPage');
  $(document).on('click', '#getNextPage', (event) => {
    search(nextPageToken);
  });
}

/**
 * Grab the video recommendations for a video.  This does not get recommendations based on what you watch,
 * as that would defeat the main purpose of using FreeTube.  At any time you can check the video on HookTube
 * and compare the recommendations there.  They should be nearly identical.
 *
 * @param {string} videoId - The video ID of the video to get recommendations from.
 */
function showVideoRecommendations(videoId) {
  youtubeAPI('search', {
    part: 'id',
    type: 'video',
    relatedToVideoId: videoId,
    maxResults: 15,
  }, function(data) {
    let grabDuration = getDuration(data.items);
    grabDuration.then((videoList) => {
      videoList.items.forEach((video) => {
        const snippet = video.snippet;
        const videoDuration = parseVideoDuration(video.contentDetails.duration);

        const recommTemplate = require('./templates/recommendations.html')
        mustache.parse(recommTemplate);
        const rendered = mustache.render(recommTemplate, {
          videoId: video.id,
          videoTitle: snippet.title,
          channelName: snippet.channelTitle,
          videoThumbnail: snippet.thumbnails.medium.url,
          videoDuration: videoDuration,
          publishedDate: dateFormat(snippet.publishedAt, "mmm dS, yyyy")
        });
        const recommendationHtml = $('#recommendations').html();
        $('#recommendations').html(recommendationHtml + rendered);
      });
    });
  });
}

/**
 * Check if a link is a valid YouTube/HookTube link and play that video. Gets input
 * from the #jumpToInput element.
 *
 * @return {Void}
 */
function parseVideoLink() {
  let input = document.getElementById('jumpToInput').value;

  if (input === '') {
    return;
  }

  // The regex to get the video id from a YouTube link.  Thanks StackOverflow.
  let rx = /^.*(?:(?:(you|hook)tu\.?be\/|v\/|vi\/|u\/\w\/|embed\/)|(?:(?:watch)?\?v(?:i)?=|\&v(?:i)?=))([^#\&\?]*).*/;

  let match = input.match(rx);

  console.log(match);

  // Play video if a match is found.
  try {
    playVideo(match[2]);
  } catch (err) {
    showToast('Video Not Found');
  }
}

/**
 * Convert duration into a more readable format
 *
 * @param {string} durationString - The string containing the video duration.  Formated as 'PT12H34M56S'
 *
 * @return {string} - The formated string. Ex: 12:34:56
 */
function parseVideoDuration(durationString) {
  let match = durationString.match(/PT(\d+H)?(\d+M)?(\d+S)?/);
  let duration = '';

  match = match.slice(1).map(function(x) {
    if (x != null) {
      return x.replace(/\D/, '');
    }
  });

  let hours = (parseInt(match[0]) || 0);
  let minutes = (parseInt(match[1]) || 0);
  let seconds = (parseInt(match[2]) || 0);

  if (hours != 0) {
    duration = hours + ':';
  } else {
    duration = minutes + ':';
  }

  if (hours != 0 && minutes < 10) {
    duration = duration + '0' + minutes + ':';
  } else if (hours != 0 && minutes > 10) {
    duration = duration + minutes + ':';
  } else if (hours != 0 && minutes == 0) {
    duration = duration + '00:';
  }

  if (seconds == 0) {
    duration = duration + '00';
  } else if (seconds < 10) {
    duration = duration + '0' + seconds;
  } else {
    duration = duration + seconds;
  }

  return duration;
}

/**
 * Grab the most popular videos over the last couple of days and display them.
 *
 * @return {Void}
 */
function showMostPopular() {
  clearMainContainer();
  startLoadingAnimation();

  // Get the date of 2 days ago.
  var d = new Date();
  d.setDate(d.getDate() - 2);

  // Grab all videos published 2 days ago and after and order them by view count.
  // These are the videos that are considered as 'most popular' and is how similar
  // Applications grab these.  Videos in the 'Trending' tab on YouTube will be different.
  // And there is no way to grab those videos.
  youtubeAPI('search', {
    part: 'id',
    order: 'viewCount',
    type: 'video',
    publishedAfter: d.toISOString(),
    maxResults: 50,
  }, function(data) {
    createVideoListContainer('Most Popular:');
    console.log(data);
    let grabDuration = getDuration(data.items);

    grabDuration.then((videoList) => {
      console.log(videoList);
      videoList.items.forEach(displayVideo);
    });
    stopLoadingAnimation();
  });
}

/**
 * Create a link of the video to HookTube or YouTube and copy it to the user's clipboard.
 *
 * @param {string} website - The website to watch the video on.
 * @param {string} videoId - The video ID of the video to add to the URL
 *
 * @return {Void}
 */
function copyLink(website, videoId) {
  // Create the URL and copy to the clipboard.
  const url = 'https://' + website + '.com/watch?v=' + videoId;
  clipboard.writeText(url);
  showToast('URL has been copied to the clipboard');
}

/**
 * Get the YouTube embeded player of a video as well as channel information..
 *
 * @param {string} videoId - The video ID of the video to get.
 *
 * @return {promise} - The HTML of the embeded player
 */
function getChannelAndPlayer(videoId) {
  console.log(videoId);
  return new Promise((resolve, reject) => {
    youtubeAPI('videos', {
      part: 'snippet,player',
      id: videoId,
    }, function(data) {
      let embedHtml = data.items[0].player.embedHtml;
      embedHtml = embedHtml.replace('src="', 'src="https:');
      embedHtml = embedHtml.replace('width="480px"', '');
      embedHtml = embedHtml.replace('height="270px"', '');
      embedHtml = embedHtml.replace(/\"/g, '&quot;');
      resolve([embedHtml, data.items[0].snippet.channelId]);
    });
  });
}

/**
 * Check to see if the video URLs are valid. Change the video quality if one is not.
 * The API will grab video URLs, but they will sometimes return a 404.  This
 * is why this check is needed.  The video URL will typically be resolved over time.
 *
 * @param {string} video480p - The URL to the 480p video.
 * @param {string} video720p - The URL to the 720p video.
 */
function checkVideoUrls(video480p, video720p) {
  const currentQuality = $('#currentQuality').html();
  let buttonEmbed = document.getElementById('qualityEmbed');

  let valid480 = false;

  if (typeof(video480p) !== 'undefined') {
    let get480pUrl = fetch(video480p);
    get480pUrl.then((status) => {
      switch (status.status) {
        case 404:
          showToast('Found valid URL for 480p, but returned a 404. Video type might be available in the future.');
          $(document).off('click', '#quality480p');
          $(document).on('click', '#quality480p', (event) => {
            changeQuality('');
          });
          buttonEmbed.click();
          return;
          break;
        case 403:
          showToast('This video is unavailable in your country.');
          $(document).off('click', '#quality480p');
          $(document).on('click', '#quality480p', (event) => {
            changeQuality('');
          });
          return;
          break;
        default:
          console.log('480p is valid');
          if (currentQuality === '720p' && typeof(video720p) === 'undefined') {
            changeQuality(video480p);
          }
          break;
      }
    });
  }

  if (typeof(video720p) !== 'undefined') {
    let get720pUrl = fetch(video720p);
    get720pUrl.then((status) => {
      switch (status.status) {
        case 404:
          showToast('Found valid URL for 720p, but returned a 404. Video type might be available in the future.');
          $(document).off('click', '#quality720p');
          $(document).on('click', '#quality720p', (event) => {
            changeQuality('');
          });
          if (typeof(valid480) !== 'undefined') {
            changeQuality(video480p, '480p');
          }
          break;
        case 403:
          showToast('This video is unavailable in your country.');
          $(document).off('click', '#quality720p');
          $(document).on('click', '#quality720p', (event) => {
            changeQuality('');
          });
          return;
          break;
        default:
          console.log('720p is valid');
          if (currentQuality === '720p') {
            return;
          }
          break;
      }
    });
  }
}