// 引入modules
const fs = require('fs');
const path = require('path');
const dbUtils = require(global.useMysqlPool ? '../utils/dbPoolUtils' : '../utils/dbUtils');
const sleepUtils = require('../utils/sleepUtils');

// 数据库连接池
dbUtils.create({
    database: "neteaseMusic",   // 指定数据库
    connectionLimit: global.connectionLimit || 10,        // 设置数据库连接池数量
});
global.dbUtils = dbUtils;
console.log("global.useMysqlPool:", !!global.useMysqlPool);

// 两次请求之间停顿时间
global.sleepTime = 10;

// 引入utils
const songInfoUtils = require('./src/getInfo/songInfoUtils');
const artistInfoUtils = require('./src/getInfo/artistInfoUtils');
const albumInfoUtils = require('./src/getInfo/albumInfoUtils');
const lyricInfoUtils = require('./src/getInfo/lyricInfoUtils');
const commentUtils = require('./src/getInfo/commentUtils');
// const playlistUtils = require('./src/getInfo/playlistUtils');

/**
 * 测试
 */
async function test() {
    console.log("neteaseMusic test...");

    // 不是所有歌手都有个人主页 例如 https://music.163.com/#/artist?id=1079075

    // let res = await albumInfoUtils.fetch({ albumId: "9156", debug: true });
    // let res = await artistInfoUtils.fetch({ artistId: "12023508" });
    // let res = await songInfoUtils.fetch({ songId: "437608327" });
    // let res = await playlistUtils.fetch({ songId: "2320041657", debug: true });

    // let res = await albumInfoUtils.getFromDatabase({ albumId: "9156" });
    // let res = await artistInfoUtils.getFromDatabase({ artistId: "12023508" });
    // let res = await songInfoUtils.getFromDatabase({ songId: "437608327" });

    console.log(res);
}

/**
 * 主函数
 */
async function main(args) {
    console.log("neteaseMusic Start fetch ...");
    while (true) {
        // // 删除脏数据
        // var affectedRows1 = await dbUtils.query(`DELETE FROM song_artist_relation WHERE song_id = 0 OR artist_id = 0`, []);
        // var affectedRows2 = await dbUtils.query(`DELETE FROM song_album_relation WHERE song_id = 0 OR album_id = 0`, []);
        // console.log(`删除脏数据 affectedRows:`, affectedRows1.affectedRows, affectedRows2.affectedRows);

        if (args.utils == "song")
            await songInfoUtils.fetchAll({ args: args });
        else if (args.utils == "album")
            await albumInfoUtils.fetchAll({ args: args });
        else if (args.utils == "artist")
            await artistInfoUtils.fetchAll({ args: args });
        else if (args.utils == "lyric")
            await lyricInfoUtils.fetchAll({ args: args });
        else if (args.utils == "comment")
            await commentUtils.fetchAll({ args: args });
        else {
            console.log("utils参数不匹配，退出");
            return;
        }
        await sleepUtils.sleep(2000);
    }
}

/**
 * 数据更新 (重新爬取)
 */
async function update() {
    console.log("neteaseMusic Start update ...");
    while (true) {
        await albumInfoUtils.fetchAll({ isUpdate: true });
        await sleepUtils.sleep(2000);
    }
}

/**
 * 统计数据库中数据
 */
let oldWatchParam = {};
async function watch() {
    console.log(`开始统计 ... ${new Date(Date.now() + 8 * 3600 * 1000).toISOString()}`);
    let statisticTime = Date.now();
    let newWatchParam = {};
    let sqls = [
        // InnoDB count(*) 会扫描全表，粗略数据可以通过 show table status 查看
        {
            name: "songCount",
            sql: `SELECT count(*) AS count FROM song`,
        }, {
            name: "songWaiting",
            sql: `SELECT count(DISTINCT song_id) AS count
                FROM ( SELECT song_id FROM song_artist_relation UNION SELECT song_id FROM song_album_relation ) t_tmp
                WHERE song_id NOT IN ( SELECT song_id FROM song )`,
        }, {
            name: "albumCount",
            sql: `SELECT count(*) AS count FROM album`,
        }, {
            name: "albumWaiting",
            sql: `SELECT count( DISTINCT album_id ) as count FROM song_album_relation WHERE album_id NOT IN ( SELECT album_id FROM album )`,
        }, {
            name: "artistCount",
            sql: `SELECT count(*) AS count FROM artist`,
        }, {
            name: "artistWaiting",
            sql: `SELECT count( DISTINCT artist_id ) as count FROM song_artist_relation WHERE artist_id NOT IN ( SELECT artist_id FROM artist )`,
        }, {
            name: "lyricCount",
            sql: `SELECT count(*) AS count FROM lyric`,
        }, {
            name: "commentCount",
            sql: `SELECT count( DISTINCT song_id ) AS count FROM comment`,
        }, {
            name: "commentTotalCount",
            sql: `SELECT count(*) AS count FROM comment`,
        }, {
            name: "userCount",
            sql: `SELECT count(*) AS count FROM user`,
        }, {
            name: "songAlbumCount",
            sql: `SELECT count(*) AS count FROM song_album_relation`,
        }, {
            name: "songArtistCount",
            sql: `SELECT count(*) AS count FROM song_artist_relation`,
        }
    ];
    let sqlsTimeSpent = 0;
    let promiseList = [];
    for (let i = 0; i < sqls.length; i++) {
        const sql = sqls[i];
        if (!sql.sql) continue; // 跳过注释掉SQL的项
        promiseList.push(new Promise(async (resolve, reject) => {
            // console.log(`query ${sql.name} ...`);
            let sqlStartTime = Date.now();
            let result = await dbUtils.query(sql.sql, []);
            let sqlTimeSpent = Date.now() - sqlStartTime;
            sqlsTimeSpent += sqlTimeSpent;
            newWatchParam[sql.name] = result[0].count;
            console.log(`query ${sql.name} finished.\tspend time: ${sqlTimeSpent}ms (${(sqlTimeSpent / 1000).toFixed(2)}s),\tcount: ${newWatchParam[sql.name]}`);
            resolve();
        }));
    }
    await Promise.all(promiseList);

    // let tableCountResult = await dbUtils.query("show table status");
    // let tableCount = {}; // 查询近似值代替精确查询
    // tableCountResult.forEach(rowData => tableCount[rowData.Name] = rowData.Rows);
    // newWatchParam['commentTotalCount'] = tableCount['comment'];

    let statisticTimeDelta = Date.now() - statisticTime;
    let statisticsString = [
        ``,
        `统计完成 ${new Date(Date.now() + 8 * 3600 * 1000).toISOString()}`,
        `spend time: ${statisticTimeDelta}ms (${(statisticTimeDelta / 1000).toFixed(2)}s; ${(statisticTimeDelta / (60 * 1000)).toFixed(2)}min), sql query time (sum): ${sqlsTimeSpent}ms (${(sqlsTimeSpent / 1000).toFixed(2)}s; ${(sqlsTimeSpent / (60 * 1000)).toFixed(2)}min)`,
        `[与上次运行统计时相比]`,
        [
            `song: ${newWatchParam['songCount'] - oldWatchParam['songCount']}`,
            `album: ${newWatchParam['albumCount'] - oldWatchParam['albumCount']}`,
            `artist: ${newWatchParam['artistCount'] - oldWatchParam['artistCount']}`,
            `lyric: ${newWatchParam['lyricCount'] - oldWatchParam['lyricCount']}`,
            `comment: ${newWatchParam['commentCount'] - oldWatchParam['commentCount']}(song)/${newWatchParam['commentTotalCount'] - oldWatchParam['commentTotalCount']}(comment)`,
            `user: ${newWatchParam['userCount'] - oldWatchParam['userCount']}`,
        ].join(', '),
        `[已爬取]`,
        [
            `song: ${newWatchParam['songCount']}`,
            `album: ${newWatchParam['albumCount']}`,
            `artist: ${newWatchParam['artistCount']}`,
            `lyric: ${newWatchParam['lyricCount']}`,
            `comment: ${newWatchParam['commentCount']}(song)/${newWatchParam['commentTotalCount']}(comment)`,
            `user: ${newWatchParam['userCount']}`,
        ].join(', '),
        `[待爬取]`,
        [
            `song: ${newWatchParam['songWaiting']}`,
            `album: ${newWatchParam['albumWaiting']}`,
            `artist: ${newWatchParam['artistWaiting']}`,
            `lyric: ${newWatchParam['songCount'] - newWatchParam['lyricCount']}`,
            `comment: ${newWatchParam['songCount'] - newWatchParam['commentCount']}`,
            `user: 未知`,
        ].join(', '),
        `[总计] (已爬取 + 待爬取)`,
        [
            `song: ${newWatchParam['songCount'] + newWatchParam['songWaiting']}`,
            `album: ${newWatchParam['albumCount'] + newWatchParam['albumWaiting']}`,
            `artist: ${newWatchParam['artistCount'] + newWatchParam['artistWaiting']}`,
            `lyric: ${newWatchParam['songCount']}`,
            `comment: ${newWatchParam['songCount']}`,
            `user: ${newWatchParam['userCount']}`,
        ].join(', '),
        `[关联关系统计]`,
        `song-album: ${newWatchParam['songAlbumCount']}, song-artist: ${newWatchParam['songArtistCount']}`,
        ``
    ].join('\n');
    console.log(statisticsString);
    oldWatchParam = newWatchParam;
}

/**
 * 退出程序
 */
global.checkIsExit = async function () {
    if (fs.readFileSync('stop.txt') != "1")
        return;
    console.log();
    console.log(`收到退出指令，准备退出...`);
    await sleepUtils.sleep(500);
    await dbUtils.close();
    console.log(`数据库连接池已关闭`);
    await sleepUtils.sleep(100);
    process.exit(0);
}

module.exports = {
    main: main,
    update: update,
    watch: watch,
    test: test,
}