const {Collection} = require("@projectdysnomia/dysnomia");

const playdl = require("play-dl");
const ffprobe = require("node-ffprobe");

const Command = require("../lib/command.js");
const {
  formatTime,
  selectionMessage,
  parseHtmlEntities,
} = require("../lib/utils.js");

const REGEX_YOUTUBE = /^(https?:\/\/)?(www\.)?(youtube\.com|youtu\.?be)\/.+$/;
const REGEX_YOUTUBE_PLAYLIST =
  /^(https?:\/\/)?(www\.)?(youtube\.com|youtu\.?be)\/playlist\?list=(.+)$/;
const REGEX_YOUTUBE_PLAYLIST_SHORT = /^PL[a-zA-Z0-9-_]{1,32}$/;
const REGEX_SOUNDCLOUD =
  /^((https?:\/\/)?(www\.|m\.)?soundcloud\.com\/|sc:).+\/.+$/;
const REGEX_SOUNDCLOUD_PLAYLIST =
  /^((https?:\/\/)?(www\.|m\.)?soundcloud\.com\/|sc:).+\/(sets\/.+|likes|tracks)$/;
const REGEX_FILE =
  /^(https?:\/\/)?.*\..*\/.+\.(mp3|ogg|flac|wav|webm|mp4|mov|mkv|mod|s3m|it|xm)$/;

let SOUNDCLOUD_CLIENTID;

hf.voiceStorage = hf.voiceStorage || new Collection();
const voiceStorage = hf.voiceStorage;

// https://stackoverflow.com/a/12646864 § "Updating to ES6 / ECMAScript 2015"
function shuffleArray(array) {
  for (let i = array.length - 1; i > 0; i--) {
    const j = Math.floor(Math.random() * (i + 1));
    [array[i], array[j]] = [array[j], array[i]];
  }
}

async function getSoundcloudClientID() {
  if (SOUNDCLOUD_CLIENTID != null) {
    return SOUNDCLOUD_CLIENTID;
  }
  const page = await fetch("https://soundcloud.com").then((res) => res.text());
  const scripts = page
    .match(/<script crossorigin src="(.+?)"><\/script>/g)
    .reverse();
  for (const script of scripts) {
    const url = script.match(/src="(.+?)"/)[1];
    const contents = await fetch(url).then((res) => res.text());
    if (/,client_id:"(.+?)",/.test(contents)) {
      const client_id = contents.match(/,client_id:"(.+?)",/)[1];
      SOUNDCLOUD_CLIENTID = client_id;
      return SOUNDCLOUD_CLIENTID;
    }
  }
  return null;
}

async function processPlaylist(
  url,
  type,
  shuffle = false,
  limit = -1,
  offset = 0
) {
  let playlist;

  if (type === "yt") {
    const playlistId =
      url.match(REGEX_YOUTUBE_PLAYLIST)?.[4] ??
      url.match(REGEX_YOUTUBE_PLAYLIST_SHORT)?.[0];
    if (!playlistId) return null;

    const baseUrl = `https://www.googleapis.com/youtube/v3/playlistItems?key=${hf.apikeys.google}&part=snippet&playlistId=${playlistId}&maxResults=50`;

    const data = await fetch(baseUrl).then((res) => res.json());

    playlist = data.items;

    let pageToken = data.nextPageToken;
    while (pageToken != null) {
      const pageData = await fetch(baseUrl + "&pageToken=" + pageToken).then(
        (res) => res.json()
      );
      if (pageData.nextPageToken) pageToken = pageData.nextPageToken;

      playlist = [...playlist, ...pageData.items];
    }
  } else if (type === "sc") {
    const clientId = await getSoundcloudClientID();

    if (url.indexOf("/likes") > -1) {
      let userInfo = await fetch(
        `https://api-v2.soundcloud.com/resolve?url=${url}&client_id=${clientId}&limit=500`
      ).then((res) => res.json());

      while (!userInfo.uri) {
        userInfo = await fetch(
          `https://api-v2.soundcloud.com/resolve?url=${url}&client_id=${clientId}&limit=500`
        ).then((res) => res.json());
      }

      const likesUrl =
        userInfo.uri.replace("api.", "api-v2.") +
        "/likes?limit=500&client_id=" +
        clientId;

      let currentLikes = await fetch(likesUrl).then((res) => res.json());
      playlist = currentLikes.collection;

      while (currentLikes.next_href != null) {
        currentLikes = await fetch(
          currentLikes.next_href + "&client_id=" + clientId
        ).then((res) => res.json());
        playlist = [...playlist, ...currentLikes.collection];
      }
    } else {
      playlist = await fetch(
        `https://api-v2.soundcloud.com/resolve?url=${url}&client_id=${clientId}&limit=500`
      )
        .then((res) => res.json())
        .then((obj) => obj.tracks);
    }
  }

  if (shuffle === true && playlist != null) {
    shuffleArray(playlist);
  }

  if (offset > 0) {
    playlist = playlist.slice(offset);
  }

  if (limit > 0) {
    playlist = playlist.slice(0, limit);
  }

  return playlist;
}

async function createVoiceConnection(guild_id, voice_id, text_id) {
  const state = {
    voice_id,
    text_id,
  };

  state.connection = await hf.bot.joinVoiceChannel(voice_id, {
    selfDeaf: true,
    selfMute: false,
  });
  state.queue = [];

  state.onEnd = async function () {
    if (state.queue.length > 0) {
      const next = state.queue.splice(0, 1)[0];
      await enqueue({
        guild_id,
        voice_id,
        text_id,
        url: next.url,
        type: next.type,
        addedBy: next.addedBy,
      });
    } else {
      await state.connection.disconnect();
      if (!state.__leave) {
        await hf.bot.guilds.get(guild_id).channels.get(text_id).createMessage({
          content: ":musical_note: Queue is empty, leaving voice channel.",
        });
        await hf.bot.leaveVoiceChannel(voice_id);
      }
      state.connection.off("end", state.onEnd);
      voiceStorage.delete(guild_id);
    }
  };
  state.connection.on("end", state.onEnd);
  voiceStorage.set(guild_id, state);

  return state;
}

async function enqueue({
  guild_id,
  voice_id,
  text_id,
  url,
  type,
  addedBy,
  suppress = false,
  queueNext = false,
}) {
  if (!url) return;

  const connection =
    voiceStorage.get(guild_id) ??
    (await createVoiceConnection(guild_id, voice_id, text_id));
  const textChannel = hf.bot.guilds.get(guild_id).channels.get(text_id);

  let title,
    length,
    thumbnail,
    media,
    stream = false;

  if (type == "yt") {
    let info;
    try {
      info = await playdl.video_info(url);
    } catch (err) {
      await textChannel.createMessage({
        content: `:warning: Failed to get metadata: \`\`\`\n${err}\n\`\`\``,
      });
    }

    title = parseHtmlEntities(info?.video_details?.title);
    length = info?.video_details?.durationInSec * 1000;
    thumbnail = info?.video_details?.thumbnails?.[
      info.video_details.thumbnails.length - 1
    ].url
      .replace("vi_webp", "vi")
      .replace(".webp", ".jpg");

    let formats = info?.format;
    if (formats) {
      formats = formats.filter(
        (obj) => obj.audioQuality != null && obj.container == "webm"
      );
      formats.sort((a, b) => b.bitrate - a.bitrate);
      media = formats[0].url;
    }
  } else if (type == "sc") {
    if (url?.startsWith("sc:"))
      url = url.replace(/^sc:/, "https://soundcloud.com/");
    const client_id = await getSoundcloudClientID();

    const info = await fetch(
      `https://api-v2.soundcloud.com/resolve?url=${url}&client_id=${client_id}`
    ).then((res) => res.json());

    const formatUrl = info.media.transcodings.filter(
      (obj) => !obj.snipped && obj.format.protocol == "progressive"
    )[0].url;
    const streamUrl = await fetch(`${formatUrl}?client_id=${client_id}`)
      .then((res) => res.json())
      .then((obj) => obj.url);

    title = info.title;
    length = info.duration;
    thumbnail = info.artwork_url;
    media = streamUrl;
  } else if (type == "file") {
    title = url;
    let info;

    try {
      info = await ffprobe(url).then((obj) => obj.format);
    } catch (err) {
      textChannel.createMessage({
        content: `:warning: Failed to get metadata: \`\`\`\n${err}\n\`\`\``,
      });
    }

    stream = !info.duration;

    if (info.tags) {
      title = `${
        info.tags.artist ??
        info.tags.ARTIST ??
        info.tags.album_artist ??
        info.tags.ALBUM_ARTIST ??
        "<unknown artist>"
      } - ${info.tags.title ?? info.tags.TITLE ?? "<no title>"}`;
    }

    length = info.duration ? Math.floor(info.duration) * 1000 : 0;
    media = url;
  }

  if (connection.connection.playing) {
    const queueItem = {
      url,
      type,
      title,
      length,
      addedBy,
      stream,
      id: Math.random().toString(16).substring(2),
    };

    if (queueNext === true) {
      connection.queue.splice(0, 0, queueItem);
    } else {
      connection.queue.push(queueItem);
    }

    if (suppress === false) {
      textChannel.createMessage({
        embeds: [
          {
            title: `<:ms_tick:503341995348066313> Added to queue ${
              queueNext === true ? "(next up)" : ""
            }`,
            color: 0x00cc00,
            fields: [
              {
                name: "Title",
                value: (title && title != url
                  ? `[${title}](${url})`
                  : url
                ).substring(0, 1024),
                inline: true,
              },
              {
                name: "Length",
                value: stream
                  ? "<continuous>"
                  : length
                  ? formatTime(length)
                  : "<unknown>",
                inline: true,
              },
              {
                name: "Added by",
                value: `<@${addedBy}>`,
                inline: true,
              },
            ],
            thumbnail: {
              url: thumbnail,
            },
          },
        ],
      });
    }
  } else {
    if (!media) {
      textChannel.createMessage({
        content: `:warning: No usable media was found for \`${url}\`. May possibly be due to region restrictions or paywalls.`,
      });
      return;
    }

    await connection.connection.play(media, {
      inlineVolume: true,
      voiceDataTimeout: -1,
    });

    textChannel.createMessage({
      embeds: [
        {
          title: `:musical_note: Now Playing`,
          color: 0x0088cc,
          fields: [
            {
              name: "Title",
              value: (title ? `[${title}](${url})` : url).substring(0, 1024),
              inline: true,
            },
            {
              name: "Length",
              value: stream
                ? "<continuous>"
                : length
                ? formatTime(length)
                : "<unknown>",
              inline: true,
            },
            {
              name: "Added by",
              value: `<@${addedBy}>`,
              inline: true,
            },
          ],
          thumbnail: {
            url: thumbnail,
          },
        },
      ],
    });

    connection.nowplaying = {
      title,
      addedBy,
      thumbnail,
      length,
      start: Date.now(),
      stream,
      url,
    };
  }
}

async function youtubeSearch(msg, str) {
  const {items} = await fetch(
    `https://www.googleapis.com/youtube/v3/search?key=${
      hf.apikeys.google
    }&maxResults=5&part=snippet&type=video&q=${encodeURIComponent(str)}`
  ).then((res) => res.json());

  const selection = items.map((item) => ({
    value: "https://youtu.be/" + item.id.videoId,
    key: item.id.videoId,
    display: `${parseHtmlEntities(item.snippet.title).substring(0, 99)}${
      parseHtmlEntities(item.snippet.title).length > 99 ? "…" : ""
    }`,
    description: `from ${parseHtmlEntities(item.snippet.channelTitle).substring(0, 95)}${
      parseHtmlEntities(item.snippet.channelTitle).length > 95 ? "…" : ""
    }`,
  }));

  try {
    return await selectionMessage(msg, "Search results:", selection);
  } catch (out) {
    return out;
  }
}

const NOWPLAYING_BAR_LENGTH = 30;

const command = new Command("music");
command.addAlias("m");
command.category = "misc";
command.helpText = "Music";
command.usage = "help";
command.callback = async function (
  msg,
  line,
  args,
  {shuffle = false, limit = -1, offset = 0, next = false}
) {
  if (!msg.guildID) return "This command can only be used in guilds.";

  const subcommand = args.shift();
  let argStr = args.join(" ");

  switch (subcommand) {
    case "play":
    case "p":
      if (msg.member?.voiceState?.channelID) {
        if (voiceStorage.has(msg.guildID)) {
          const connection = voiceStorage.get(msg.guildID);
          if (connection.voice_id != msg.member.voiceState.channelID) {
            return "You are in a different voice channel than the bot.";
          }
        }

        let type;
        let playlist = false;

        if (
          REGEX_YOUTUBE_PLAYLIST.test(argStr) ||
          REGEX_YOUTUBE_PLAYLIST_SHORT.test(argStr)
        ) {
          type = "yt";
          playlist = true;
        } else if (REGEX_SOUNDCLOUD_PLAYLIST.test(argStr)) {
          type = "sc";
          playlist = true;
        } else if (REGEX_YOUTUBE.test(argStr)) {
          type = "yt";
        } else if (REGEX_SOUNDCLOUD.test(argStr)) {
          type = "sc";
        } else if (REGEX_FILE.test(argStr)) {
          type = "file";
        } else if (msg.attachments.length > 0) {
          const entries = msg.attachments.filter((attachment) =>
            REGEX_FILE.test(attachment.url)
          );
          if (entries.length > 0) {
            type = "file";
            argStr = entries[0].url;
          }
        }

        if (type != null) {
          if (playlist) {
            const statusMessage = await msg.channel.createMessage({
              embeds: [
                {
                  title:
                    "<a:loading:493087964918972426> Processing playlist...",
                  description: `Fetching tracks...`,
                  color: 0xcc0088,
                },
              ],
            });
            const playlist = await processPlaylist(
              argStr,
              type,
              shuffle,
              limit,
              offset
            );
            await statusMessage.edit({
              embeds: [
                {
                  title:
                    "<a:loading:493087964918972426> Processing playlist...",
                  description: `${playlist.length} tracks`,
                  color: 0xcc0088,
                },
              ],
            });
            for (const track of playlist) {
              let url;
              if (type == "yt") {
                url = "https://youtu.be/" + track.snippet.resourceId.videoId;
              } else if (type == "sc") {
                url = track.track
                  ? track.track.permalink_url
                  : track.permalink_url;
              }

              await enqueue({
                guild_id: msg.guildID,
                voice_id: msg.member.voiceState.channelID,
                text_id: msg.channel.id,
                url,
                type,
                addedBy: msg.author.id,
                suppress: true,
              });
            }
            await statusMessage.edit({
              embeds: [
                {
                  title: "<:ms_tick:503341995348066313> Done processing",
                  description: `${playlist.length} tracks`,
                  color: 0xcc0088,
                },
              ],
            });
          } else {
            await enqueue({
              guild_id: msg.guildID,
              voice_id: msg.member.voiceState.channelID,
              text_id: msg.channel.id,
              url: argStr,
              type,
              addedBy: msg.author.id,
              queueNext: next,
            });
          }
        } else {
          if (argStr.match(/^https?:\/\//)) {
            const contentType = await fetch(argStr).then((res) =>
              res.headers.get("Content-Type")
            );
            if (
              contentType.startsWith("audio/") ||
              contentType.startsWith("video/")
            ) {
              await enqueue({
                guild_id: msg.guildID,
                voice_id: msg.member.voiceState.channelID,
                text_id: msg.channel.id,
                url: argStr,
                type: "file",
                addedBy: msg.author.id,
                queueNext: next,
              });
            } else {
              return "Unsupported content type.";
            }
          } else {
            const url = await youtubeSearch(msg, argStr);
            if (url?.startsWith("https://youtu.be/")) {
              await enqueue({
                guild_id: msg.guildID,
                voice_id: msg.member.voiceState.channelID,
                text_id: msg.channel.id,
                url,
                type: "yt",
                addedBy: msg.author.id,
                queueNext: next,
              });
            } else {
              return url;
            }
          }
        }
      } else {
        return "You are not in a voice channel.";
      }
      break;
    case "skip":
    case "s":
      if (msg.member?.voiceState?.channelID) {
        const connection = voiceStorage.get(msg.guildID);
        if (voiceStorage.has(msg.guildID)) {
          if (connection.voice_id != msg.member.voiceState.channelID) {
            return "You are in a different voice channel than the bot.";
          }
        }

        // TODO: skip lock checks
        await connection.connection.stopPlaying();
        return {reaction: "\u23ed"};
      } else {
        return "You are not in a voice channel.";
      }
    case "leave":
    case "l":
    case "stop":
      if (msg.member?.voiceState?.channelID) {
        const connection = voiceStorage.get(msg.guildID);
        if (voiceStorage.has(msg.guildID)) {
          if (connection.voice_id != msg.member.voiceState.channelID) {
            return "You are in a different voice channel than the bot.";
          }
        }

        // TODO: skip lock checks
        connection.queue = [];
        connection.__leave = true;
        await connection.connection.stopPlaying();
        connection.onEnd();
        await hf.bot.leaveVoiceChannel(msg.member.voiceState.channelID);
        return {reaction: "\uD83D\uDC4B"};
      } else {
        return "You are not in a voice channel.";
      }
    case "np": {
      if (!voiceStorage.has(msg.guildID))
        return "The bot is not in a voice channel.";

      const connection = voiceStorage.get(msg.guildID);
      const nowPlaying = connection.nowplaying;
      if (!nowPlaying || !connection.connection.playing)
        return "Nothing is currently playing.";

      const position = Date.now() - nowPlaying.start;

      const timeEnd =
        nowPlaying.length == 0 ? "\u221e" : formatTime(nowPlaying.length);
      const timePos = formatTime(position);

      const progress =
        nowPlaying.length == 0 ? 1 : position / nowPlaying.length;
      const barLength = Math.round(progress * NOWPLAYING_BAR_LENGTH);

      const bar = `\`[${"=".repeat(barLength)}${" ".repeat(
        NOWPLAYING_BAR_LENGTH - barLength
      )}]\``;
      const time = `\`${timePos}${" ".repeat(
        NOWPLAYING_BAR_LENGTH + 2 - timePos.length - timeEnd.length
      )}${timeEnd}\``;

      return {
        embed: {
          title: ":musical_note: Now Playing",
          color: 0x0088cc,
          fields: [
            {
              name: "Title",
              value: nowPlaying.title
                ? `[${nowPlaying.title}](${nowPlaying.url})`
                : nowPlaying.url,
              inline: true,
            },
            {
              name: "Added by",
              value: `<@${nowPlaying.addedBy}>`,
              inline: true,
            },
            {
              name: bar,
              value: time,
              inline: false,
            },
          ],
        },
      };
    }
    case "queue":
    case "q": {
      if (!voiceStorage.has(msg.guildID))
        return "The bot is not in a voice channel";

      const connection = voiceStorage.get(msg.guildID);
      const queue = connection.queue;
      if (queue.length === 0) return "Nothing else is currently queued";

      const nowPlaying = connection.nowplaying;

      const now = Date.now();
      let nextTrack = now + (nowPlaying.length - (now - nowPlaying.start));
      const fields = [];
      for (const index in queue.slice(0, 9)) {
        const item = queue[index];
        fields.push({
          name: item.title ?? item.url,
          value: `${item.title ? `[Link](${item.url}) - ` : ""}${formatTime(
            item.length
          )}\nAdded by: <@${item.addedBy}>\n<t:${Math.floor(
            nextTrack / 1000
          )}:R>`,
          inline: true,
        });
        nextTrack += item.length;
      }

      let totalLength = 0;
      for (const item of queue) {
        totalLength += item.length;
      }

      return {
        embed: {
          title: ":inbox_tray: Currently Queued",
          color: 0x0088cc,
          fields,
          footer: {
            text:
              (queue.length > 9 ? `Showing 9/${queue.length} items | ` : "") +
              `Total length: ${formatTime(totalLength)}`,
          },
        },
      };
    }
    case "remove":
    case "qr":
      if (msg.member?.voiceState?.channelID) {
        const connection = voiceStorage.get(msg.guildID);
        if (voiceStorage.has(msg.guildID)) {
          if (connection.voice_id != msg.member.voiceState.channelID) {
            return "You are in a different voice channel than the bot.";
          }
        }

        let queue = connection.queue;
        if (queue.length === 0) return "Nothing else is currently queued";

        const hasManageMessages = msg.member.permissions.has("manageMessages");
        if (!hasManageMessages)
          queue = queue.filter((item) => item.addedBy == msg.member.id);

        if (queue.length === 0) return "You currently have nothing queued";

        const toRemove = await selectionMessage(
          msg,
          "Choose items to remove",
          queue.slice(0, 25).map((item) => {
            const user = hf.bot.users.get(item.addedBy);
            return {
              key: item.id,
              display: (item.title ?? item.url).substr(0, 100),
              description: hasManageMessages
                ? `Added by: ${user.username}#${user.discriminator}`
                : "",
            };
          }),
          30000,
          Math.min(queue.length, 25)
        );

        if (Array.isArray(toRemove)) {
          connection.queue = connection.queue.filter(
            (item) => !toRemove.includes(item.id)
          );
          return `Removed ${toRemove.length} item(s).`;
        } else {
          return toRemove;
        }
      } else {
        return "You are not in a voice channel";
      }
    case "lock":
    case "unlock":
      return "TODO";
    case "help":
    case "h":
      return `**__Music Subcommands__**
\u2022 \`play/p [url|search string]\` - Play or add to queue. Supports: YouTube, SoundCloud, mp3/flac/ogg/wav/webm/mp4/mov/mkv/mod/s3m/it/xm, streams
\u2022 \`queue/q (page)\` - Lists the current queue.
\u2022 \`leave/l/stop\` - Leaves the voice channel.
\u2022 \`np\` - Shows whats currently playing.
\u2022 \`skip/s\` - Skips whats currently playing.
\u2022 \`remove/qr\` - Remove an item from queue.
\u2022 \`lock\` - Lock skipping and queue. (manage messages)
\u2022 \`unlock\` - Unlock skipping and queue. (manage messages)
\u2022 \`help/h\` - This text.`;
    default:
      return `Invalid/missing subcommand. See \`${hf.config.prefix}music help\` for all subcommands.`;
  }
  return null; // shutting up eslint
};
hf.registerCommand(command);