const { EmbedBuilder } = require('discord.js');
const { 
  createAudioPlayer, 
  joinVoiceChannel,
  AudioPlayerStatus,
  VoiceConnectionStatus,
  entersState,
} = require('@discordjs/voice');
const { getVideoInfo, playSong, preloadSong, formatDuration, safeCleanup, clearSongBuffer } = require('../utils/player');
const { requireVoiceChannel } = require('../utils/helpers');

function createSongsFromVideos(videos, requestedBy) {
  return videos.map(v => ({
    title: v.title,
    url: v.url,
    duration: v.duration,
    thumbnail: v.thumbnail,
    requestedBy: requestedBy,
  }));
}

function onPlayerIdle(interaction, queue) {
  console.log(`[PLAYER IDLE] Guild: ${interaction.guild.id}, Loop mode: ${queue.loopMode}, Is seeking: ${queue.isSeeking || false}`);
  
  safeCleanup(queue, 'Player Idle');
  
  if (queue.isSeeking) {
    console.log(`[IDLE SKIP] Skipping queue shift because seek is in progress`);
    return;
  }
  
  if (queue.loopMode === 'song') {
    if (queue.songs[0]) {
      queue.songs[0].retryCount = 0;
    }
    playSong(interaction.guild.id, queue);
  } else if (queue.loopMode === 'queue') {
    const finishedSong = queue.songs.shift();
    queue.songs.push(finishedSong);
    if (queue.songs.length > 0) {
      playSong(interaction.guild.id, queue);
    }
  } else {
    const finishedSong = queue.songs.shift();
    clearSongBuffer(finishedSong, 'finished playing');
    if (queue.songs.length > 0) {
      playSong(interaction.guild.id, queue);
    } else {
      console.log(`[QUEUE EMPTY] Guild: ${interaction.guild.id}`);
    }
  }
}

function onPlayerError(error, interaction, queue) {
  console.error('Audio player error:', error);
  safeCleanup(queue, 'Player Error');
  
  if (queue.isSeeking) {
    console.log(`[ERROR DURING SEEK] Not shifting queue, seek in progress`);
    queue.isSeeking = false;
    return;
  }
  
  queue.songs.shift();
  if (queue.songs.length > 0) {
    playSong(interaction.guild.id, queue);
  }
}

function onPlayerAutoPaused(player) {
  console.warn('Player auto-paused, attempting to resume...');
  try {
    player.unpause();
  } catch (err) {
    console.error('Failed to unpause:', err);
  }
}

function onConnectionError(error, queue) {
  console.error('Voice connection error:', error);
  safeCleanup(queue, 'Connection Error');
}

async function onConnectionDisconnected(connection, queues, guildId) {
  try {
    await Promise.race([
      entersState(connection, VoiceConnectionStatus.Signalling, 5000),
      entersState(connection, VoiceConnectionStatus.Connecting, 5000),
    ]);
  } catch (error) {
    connection.destroy();
    queues.delete(guildId);
  }
}

function onConnectionDestroyed(queues, guildId) {
  queues.delete(guildId);
}

function setupPlayerEventListeners(player, interaction, queue) {
  player.on(AudioPlayerStatus.Idle, () => onPlayerIdle(interaction, queue));
  player.on('error', (error) => onPlayerError(error, interaction, queue));
  player.on(AudioPlayerStatus.AutoPaused, () => onPlayerAutoPaused(player));
}

function setupConnectionEventListeners(connection, queues, guildId, queue) {
  connection.on('error', (error) => onConnectionError(error, queue));
  connection.on(VoiceConnectionStatus.Disconnected, () => 
    onConnectionDisconnected(connection, queues, guildId)
  );
  connection.on(VoiceConnectionStatus.Destroyed, () => 
    onConnectionDestroyed(queues, guildId)
  );
}

async function createVoiceConnection(voiceChannel, interaction) {
  const connection = joinVoiceChannel({
    channelId: voiceChannel.id,
    guildId: interaction.guild.id,
    adapterCreator: voiceChannel.guild.voiceAdapterCreator,
  });

  try {
    await entersState(connection, VoiceConnectionStatus.Ready, 30000);
    return connection;
  } catch (error) {
    console.error('Failed to join voice channel:', error);
    connection.destroy();
    throw error;
  }
}

async function initializeQueue(voiceChannel, interaction, queues, songs) {
  const player = createAudioPlayer();
  let connection;
  
  try {
    connection = await createVoiceConnection(voiceChannel, interaction);
  } catch (error) {
    return null;
  }

  connection.subscribe(player);

  const queue = {
    voiceChannel,
    connection,
    player,
    songs: songs,
    volume: 50,
    isPlaying: false,
    loopMode: 'off',
  };

  queues.set(interaction.guild.id, queue);

  setupPlayerEventListeners(player, interaction, queue);
  setupConnectionEventListeners(connection, queues, interaction.guild.id, queue);

  return queue;
}

function addSongsToQueue(queue, songs, interaction) {
  const oldLength = queue.songs.length;
  const wasIdle = queue.player.state.status === AudioPlayerStatus.Idle;
  
  songs.forEach(song => queue.songs.push(song));
  const newLength = queue.songs.length;
  
  console.log(`[QUEUE ADD] Guild: ${interaction.guild.id}, Added ${songs.length} songs, Queue: ${oldLength} -> ${newLength}, Player state: ${queue.player.state.status}, Was idle: ${wasIdle}`);
  
  if (wasIdle && oldLength === 0 && queue.songs.length > 0) {
    if (queue.isSeeking) {
      console.log(`[AUTO-PLAY BLOCKED] Seek in progress, not starting playback`);
    } else {
      console.log(`[AUTO-PLAY] Starting playback, songs in queue: ${queue.songs.length}`);
      playSong(interaction.guild.id, queue);
    }
  }
  
  if (queue.songs.length >= 2) {
    const nextSong = queue.songs[1];
    if (!nextSong.audioBuffer && !nextSong.isPreloading) {
      console.log(`[PRELOAD TRIGGER] Preloading next song: ${nextSong.title}`);
      preloadSong(nextSong).catch(() => {});
    }
  }

  return wasIdle;
}

function createNewPlaybackEmbed(firstSong, isPlaylist, songs) {
  const embed = new EmbedBuilder()
    .setColor(0x00ff00)
    .setTitle(isPlaylist ? 'Playlist Added' : 'Now Playing')
    .setDescription(`**${firstSong.title}**`)
    .addFields(
      { name: 'Duration', value: formatDuration(firstSong.duration), inline: true },
      { name: 'Requested by', value: firstSong.requestedBy, inline: true }
    )
    .setThumbnail(firstSong.thumbnail);

  if (isPlaylist) {
    embed.addFields({ name: 'Playlist', value: `${songs.length} songs added to queue` });
  }

  return embed;
}

function createAddToQueueEmbed(firstSong, isPlaylist, songs, queuePosition) {
  const embed = new EmbedBuilder()
    .setColor(0x00ff00)
    .setTitle(isPlaylist ? 'Playlist Added to Queue' : 'Added to Queue')
    .setDescription(`**${firstSong.title}**`)
    .addFields(
      { name: 'Position', value: `${queuePosition}`, inline: true },
      { name: 'Requested by', value: firstSong.requestedBy, inline: true }
    )
    .setThumbnail(firstSong.thumbnail);

  if (isPlaylist) {
    embed.addFields({ name: 'Playlist', value: `${songs.length} songs added to queue` });
  }

  return embed;
}

async function handlePlay(interaction, queues) {
  await interaction.deferReply();
  
  const query = interaction.options.getString('query');
  const voiceChannel = requireVoiceChannel(interaction);
  if (!voiceChannel) return;
  
  const videoInfo = await getVideoInfo(query);
  if (!videoInfo) {
    return interaction.editReply('Could not find that video!');
  }

  const isPlaylist = videoInfo.isPlaylist;
  const videos = videoInfo.videos;

  if (!videos || videos.length === 0) {
    return interaction.editReply('Could not find any videos!');
  }

  const songs = createSongsFromVideos(videos, interaction.user.tag);
  const firstSong = songs[0];

  let queue = queues.get(interaction.guild.id);

  if (!queue) {
    queue = await initializeQueue(voiceChannel, interaction, queues, songs);
    
    if (!queue) {
      return interaction.editReply('Failed to join voice channel! Try again.');
    }

    const embed = createNewPlaybackEmbed(firstSong, isPlaylist, songs);
    interaction.editReply({ embeds: [embed] });
    playSong(interaction.guild.id, queue);
  } else {
    const queuePosition = queue.songs.length - songs.length + 1;
    addSongsToQueue(queue, songs, interaction);
    
    const embed = createAddToQueueEmbed(firstSong, isPlaylist, songs, queuePosition);
    interaction.editReply({ embeds: [embed] });
  }
}

module.exports = { handlePlay };