var https = require('https');
var http = require('http');
var crypto = require('crypto');
var querystring = require('querystring');

// ===== 通用HTTP请求 =====
function doRequest(protocol, options, postData) {
  return new Promise(function(resolve, reject) {
    var client = protocol === 'https' ? https : http;
    var req = client.request(options, function(res) {
      var chunks = [];
      res.on('data', function(chunk) { chunks.push(chunk); });
      res.on('end', function() {
        var buf = Buffer.concat(chunks);
        var body;
        try {
          body = JSON.parse(buf.toString('utf8'));
        } catch (e) {
          body = buf.toString('utf8');
        }
        resolve({ body: body, statusCode: res.statusCode, headers: res.headers });
      });
    });
    req.on('error', function(err) { reject(err); });
    req.setTimeout(15000, function() { req.destroy(); reject(new Error('timeout')); });
    if (postData) req.write(postData);
    req.end();
  });
}

function requestUrl(urlStr, method, headers, body) {
  var parsed = new URL(urlStr);
  var protocol = parsed.protocol.replace(':', '');
  var options = {
    hostname: parsed.hostname,
    port: parsed.port || (protocol === 'https' ? 443 : 80),
    path: parsed.pathname + parsed.search,
    method: method || 'GET',
    headers: headers || {}
  };
  var postData = null;
  if (body) {
    if (typeof body === 'string') {
      postData = Buffer.from(body, 'utf8');
    } else if (Buffer.isBuffer(body)) {
      postData = body;
    } else {
      postData = Buffer.from(JSON.stringify(body), 'utf8');
      if (!options.headers['Content-Type']) options.headers['Content-Type'] = 'application/json';
    }
    if (postData) options.headers['Content-Length'] = postData.length;
  }
  return doRequest(protocol, options, postData);
}

function formatPlayTime(seconds) {
  if (!seconds) return '00:00';
  var m = Math.floor(seconds / 60);
  var s = Math.floor(seconds % 60);
  return (m < 10 ? '0' + m : m) + ':' + (s < 10 ? '0' + s : s);
}

// ===== 搜索实现 =====
function musicSearch(str, page, limit) {
  var url = 'http://mobilecdn.kugou.com/api/v3/search/song?showtype=14&highlight=em&pagesize=' + limit + '&page=' + page + '&keyword=' + encodeURIComponent(str);
  return requestUrl(url, 'GET', { 'User-Agent': 'Mozilla/5.0 (Linux; Android 10)' }).then(function(res) {
    if (res.body && res.body.data && res.body.data.info) return res.body.data.info;
    throw new Error('kg search failed');
  });
}

function handleSearchResult(rawList) {
  var list = [];
  for (var i = 0; i < rawList.length; i++) {
    var item = rawList[i];
    var types = [];
    var _types = {};
    types.push({ type: '128k', size: '' }); _types['128k'] = { size: '' };
    types.push({ type: '320k', size: '' }); _types['320k'] = { size: '' };
    list.push({
      singer: item.singername || '',
      name: item.songname || '',
      albumName: item.album_name || '',
      albumId: item.album_id || '',
      source: 'kg',
      interval: item.duration ? formatPlayTime(item.duration) : '',
      songmid: item.hash || item.audio_id || '',
      songId: item.hash || item.audio_id || '',
      img: item.img || '',
      lrc: null,
      types: types, _types: _types, typeUrl: {}
    });
  }
  return list;
}

function search(str, page, limit, retryNum) {
  if (retryNum === undefined) retryNum = 0;
  if (++retryNum > 3) return Promise.reject(new Error('try max num'));
  if (!limit) limit = 30;
  return musicSearch(str, page, limit).then(function(rawList) {
    var list = handleSearchResult(rawList);
    return { list: list, allPage: page + 1, limit: limit, total: list.length * 10, source: 'kg' };
  });
}

// ===== 播放链接 =====
function getUrl(songInfo, type) {
  var q = type || '128k';
  var songId = songInfo.songmid || songInfo.id || '';
  var ceruKey = process.env.ceru_key || '';
  var headers = { 'User-Agent': 'QZMusic/2.0' };
  if (ceruKey) headers['X-API-Key'] = ceruKey;
  return requestUrl('https://source.shiqianjiang.cn/api/music/url?source=kg&songId=' + encodeURIComponent(songId) + '&quality=' + encodeURIComponent(q), 'GET', headers)
    .then(function(res) {
      if (res.body && typeof res.body === 'object' && res.body.url) return res.body.url;
      if (res.body && typeof res.body === 'object' && res.body.data && res.body.data.url) return res.body.data.url;
      if (typeof res.body === 'string' && res.body.indexOf('http') === 0) return res.body;
      return '';
    }).catch(function() { return ''; });
}

// ===== 封面图 =====
function getPic(songInfo) {
  if (songInfo.img) return Promise.resolve(songInfo.img);
  return Promise.resolve('');
}

// ===== 歌词 =====
function getLyric(songInfo) {
  var hash = songInfo.songmid || '';
  if (!hash) return Promise.resolve('');
  return requestUrl('https://krcs.kugou.com/search?ver=1&man=yes&client=mobi&keyword=&duration=&hash=' + encodeURIComponent(hash) + '&album_audio_id=', 'GET', {
    'User-Agent': 'Mozilla/5.0 (Linux; Android 10)'
  }).then(function(res) {
    if (res.body && res.body.candidates && res.body.candidates.length) {
      var id = res.body.candidates[0].id;
      var accesskey = res.body.candidates[0].accesskey;
      return requestUrl('https://krcs.kugou.com/download?ver=1&client=pc&id=' + encodeURIComponent(id) + '&accesskey=' + encodeURIComponent(accesskey) + '&fmt=lrc&charset=utf8', 'GET', {
        'User-Agent': 'Mozilla/5.0 (Linux; Android 10)'
      }).then(function(res2) {
        if (res2.body && res2.body.content) {
          try { return Buffer.from(res2.body.content, 'base64').toString('utf8'); } catch(e) { return ''; }
        }
        return '';
      });
    }
    return '';
  }).catch(function() { return ''; });
}

// ===== 音乐详情 =====
function musicDetail(songmid) {
  return Promise.resolve(null);
}
function musicInfo(songmid) { return musicDetail(songmid); }

// ===== 热搜 =====
function hotSearch() { return Promise.resolve({ source: 'kg', list: [] }); }

// ===== 搜索建议 =====
function tipSearch(str) { return Promise.resolve({ order: [], songs: [], artists: [], albums: [], playlists: [] }); }

// ===== 榜单 =====
function leaderboard() { return Promise.resolve([]); }

// ===== 歌单 =====
function songList() { return Promise.resolve({ list: [], total: 0, page: 1, source: 'kg' }); }

// ===== 歌手 =====
function singer() { return Promise.resolve({ source: 'kg', list: [], total: 0 }); }

// ===== 专辑 =====
function album() { return Promise.resolve({ source: 'kg', list: [], total: 0 }); }

// ===== 插件信息 =====
var pluginInfo = {
  id: 'koneko_ceru_kg',
  name: '酷狗音乐 - Koneko 聆澜',
  version: '0.0.3',
  source: 'kg',
  description: '酷狗音乐音源，基于 CeruMusic musicSdk 搜索 + Ceru 播放接口'
};

module.exports = {
  pluginInfo: pluginInfo,
  musicSearch: { search: search },
  tipSearch: { search: tipSearch },
  hotSearch: { getList: hotSearch },
  leaderboard: { getBoards: leaderboard },
  songList: { search: songList, getTags: function() { return Promise.resolve({ tags: [], hotTag: [], source: 'kg' }); }, getList: songList },
  singer: { getInfo: singer, getSongList: singer, getAlbumList: singer },
  album: { getInfo: album, getSongList: album },
  getLyric: getLyric,
  getPic: getPic,
  getUrl: getUrl,
  musicDetail: musicDetail,
  musicInfo: musicInfo
};