const fs = require('fs');
const path = require('path');

const sleepUtils = require('../../../utils/sleepUtils');

const dbUtils = global.dbUtils;

const { song_detail } = require('NeteaseCloudMusicApi');

// 从数据库中查出还缺少的歌曲，并进行爬取
async function fetchAll({ args = {} }) {
    console.log("start fetching songs ...");
    let whereClause = [
        args.min ? `song_id >  ${args.min}` : '1=1',
        args.max ? `song_id <= ${args.max}` : '1=1',
    ].join(' AND ');
    var sql = `
        SELECT DISTINCT song_id FROM song_artist_relation WHERE ${whereClause} AND song_id NOT IN ( SELECT song_id FROM song )
        UNION
        SELECT DISTINCT song_id FROM song_album_relation  WHERE ${whereClause} AND song_id NOT IN ( SELECT song_id FROM song )
        ${args.order ? `ORDER BY song_id ${args.order}` : ''}
        ${args.limit ? `LIMIT ${args.limit}` : ''}
    `;
    // // 更新现有数据
    // sql = `SELECT song_id FROM song WHERE ${whereClause} AND data_version = 1`;
    // 测试用
    // sql = `SELECT song_id FROM song_artist_relation group by song_id limit 10`;
    console.log(sql);

    var songIds = await dbUtils.query(sql, []);
    songIds = songIds.map(item => item.song_id);

    // 0 - 100, 200 - 399, 400 - ..., ... - songIds.length-1
    // 0        1          2          count-1
    var step = 1000;
    var total = songIds.length;
    var count = Math.ceil(total / step);
    for (let i = 0; i < count; i++) {
        await global.checkIsExit();
        var subArray = songIds.slice(i * step, (i + 1) * step);
        console.log(`${i + 1}/${count} | song: ${subArray[0]}-${subArray.slice(-1)[0]} | ${args.min || "?"}-${args.max || "?"}`);
        try {
            await fetch({ songIdArray: subArray });
        } catch (err) {
            console.error(err);
        }
        await sleepUtils.sleep(global.sleepTime);
    }
}

// 获取音乐详情
async function fetch({ songIdArray, debug = false }) {
    // https://neteasecloudmusicapi-docs.4everland.app/#/?id=%e8%8e%b7%e5%8f%96%e6%ad%8c%e6%9b%b2%e8%af%a6%e6%83%85
    try {
        // 每一次大概可以取到1000条以上
        var songResult = await song_detail({ ids: songIdArray.join(',') });
        // fs.writeFileSync(path.join(__dirname, "../../temp", `song-${songIdArray[0]}-${songIdArray[songIdArray.length - 1]}.json`), JSON.stringify(songResult));
    } catch (errors) {
        console.error(errors);
        return;
    }
    // console.log(songResult.body.songs.map(item => JSON.stringify(item)));

    let songAlbumRel = [], songArtistRel = [];
    let songInfoList = songResult.body.songs.map(song => {
        song.ar.forEach(item => songArtistRel.push([song.id, item.id]));
        songAlbumRel.push([song.id, song.al.id || 0])
        return {
            title: song.name, // 歌曲标题
            id: song.id, // 歌曲ID
            type: song.t, // 0: 一般类型 1: 通过云盘上传的音乐，网易云不存在公开对应 2: 通过云盘上传的音乐，网易云存在公开对应
            alias: JSON.stringify(song.alia), // 别名列表，第一个别名会被显示作副标题
            pop: song.pop, // 小数，常取[0.0, 100.0]中离散的几个数值, 表示歌曲热度
            fee: song.fee, // 版权  0: 免费或无版权  1: VIP 歌曲  4: 购买专辑  8: 非会员可免费播放低音质，会员可播放高音质及下载  fee 为 1 或 8 的歌曲均可单独购买 2 元单曲
            duration: song.dt, // 歌曲时长
            quality: JSON.stringify({ h: song.h, m: song.m, l: song.l, sq: song.sq }), // 高/中/低/无损质量文件信息
            version: song.version, // 歌曲版本信息
            cd: song.cd, // None或如"04", "1/2", "3", "null"的字符串，表示歌曲属于专辑中第几张CD，对应音频文件的Tag
            no: song.no, // 表示歌曲属于CD中第几曲，0表示没有这个字段，对应音频文件的Tag
            djId: song.djId, // 0: 不是DJ节目 其他：是DJ节目，表示DJ ID
            sId: song.s_id, // 对于t == 2的歌曲，表示匹配到的公开版本歌曲ID
            originCoverType: song.originCoverType, // 0: 未知  1: 原曲  2: 翻唱
            image: "",
            pubTime: song.publishTime, // 毫秒为单位的Unix时间戳
            mv: song.mv, // 非零表示有MV ID
            single: song.single, // 0: 有专辑信息或者是DJ节目  1: 未知专辑
            noCopyrightRcmd: song.noCopyrightRcmd ? JSON.stringify(song.noCopyrightRcmd) : "", // None表示可以播，非空表示无版权

            artist: song.ar.map(item => item.id), // 歌手列表
            album: song.al.id || 0, // 专辑，如果是DJ节目(dj_type != 0)或者无专辑信息(single == 1)，则专辑id为0
        };
    });

    // console.log("songAlbumRel, songArtistRel", songAlbumRel, songArtistRel);
    // console.log("songInfoList", songInfoList);

    if (songInfoList.length == 0) return;

    console.log("插入数据库");
    if (songAlbumRel.length > 0)
        await dbUtils.query('INSERT IGNORE INTO song_album_relation (song_id, album_id) VALUES ?', [songAlbumRel]);
    await dbUtils.query('INSERT IGNORE INTO song_artist_relation (song_id, artist_id) VALUES ?', [songArtistRel]);
    await dbUtils.query(`
        INSERT INTO song (
            song_id, title, type, alias, pop, fee, quality, cd,
            no, dj_id, s_id, origin_cover_type, pub_time,
            no_copyright_rcmd, mv, single, version, data_version
        ) VALUES ? ON DUPLICATE KEY UPDATE
            title = VALUES(title), type = VALUES(type), alias = VALUES(alias), pop = VALUES(pop), fee = VALUES(fee), quality = VALUES(quality), cd = VALUES(cd),
            no = VALUES(no), dj_id = VALUES(dj_id), s_id = VALUES(s_id), origin_cover_type = VALUES(origin_cover_type), pub_time = VALUES(pub_time),
            no_copyright_rcmd = VALUES(no_copyright_rcmd), mv = VALUES(mv), single = VALUES(single), version = VALUES(version), data_version = VALUES(data_version)
    `, [songInfoList.map(songInfo => [
        songInfo.id, songInfo.title, songInfo.type, songInfo.alias, songInfo.pop, songInfo.fee, songInfo.quality, songInfo.cd,
        songInfo.no, songInfo.djId, songInfo.sId, songInfo.originCoverType, songInfo.pubTime,
        songInfo.noCopyrightRcmd, songInfo.mv, songInfo.single, songInfo.version, 2
    ])]);
    // image 因为接口没有返回，所以不更新
}

module.exports = {
    fetch: fetch,
    fetchAll: fetchAll,
}