// ==UserScript==
// @name         网易云音乐高音质支持
// @version      2.2
// @description  去除网页版网易云音乐仅可播放低音质（96Kbps）的限制，强制播放高音质版本
// @match        *://music.163.com/*
// @include      *://music.163.com/*
// @author       864907600cc
// @icon         https://secure.gravatar.com/avatar/147834caf9ccb0a66b2505c753747867
// @run-at       document-start
// @grant        none
// @namespace    http://ext.ccloli.com
// @downloadURL none
// ==/UserScript==

// getTrackURL 源码来自 Chrome 扩展程序 网易云音乐增强器(Netease Music Enhancement) by wanmingtom@gmail.com
// 菊苣这个加密算法你是怎么知道的 _(:3
var getTrackURL = function getTrackURL (dfsId) {
    var byte1 = '3' + 'g' + 'o' + '8' + '&' + '$' + '8' + '*' + '3' 
        + '*' + '3' + 'h' + '0' + 'k' + '(' + '2' + ')' + '2';
    var byte1Length = byte1.length;
    var byte2 = dfsId + '';
    var byte2Length = byte2.length;
    var byte3 = [];
    for (var i = 0; i < byte2Length; i++) {
        byte3[i] = byte2.charCodeAt(i) ^ byte1.charCodeAt(i % byte1Length);
    };

    byte3 = byte3.map(function(i) {
        return String.fromCharCode(i)
    }).join('');

    results = CryptoJS.MD5(byte3).toString(CryptoJS.enc.Base64);
    results = results.replace(/\//g, '_').replace(/\+/g, '-');

    // 使用 p1 cdn 解决境外用户无法播放的问题
    var url = 'http://p1.music.126.net/' + results + '/' + byte2 + '.mp3';
    return url;
}

var modifyURL = function modifyURL(data, parentKey) {
    console.log('API 返回了 ' + data.length + ' 首曲目');
    console.log('施放魔法！变变变！');
    data.forEach(function(elem){
        // 部分音乐没有高音质
        if (!parentKey) elem.mp3Url = getTrackURL(elem.hMusic ? elem.hMusic.dfsId : elem.mMusic ? elem.mMusic.dfsId : elem.lMusic.dfsId);
        else elem[parentKey].mp3Url = getTrackURL(elem[parentKey].hMusic ? elem.hMusic[parentKey].dfsId : elem[parentKey].mMusic ? elem.mMusic[parentKey].dfsId : elem.lMusic[parentKey].dfsId);
    });
    return data;
}


// 重新编写脚本，改用 hook xhr 的形式替换 URL 链接
var originalXMLHttpRequest = window.XMLHttpRequest;
var fakeXMLHttpRequest = function(){
    var __this__ = this;
    var _this = new originalXMLHttpRequest();
    var _this_proto = _this.constructor.prototype;
    Object.keys(originalXMLHttpRequest).forEach(function(elem){
        if (typeof originalXMLHttpRequest[elem] === 'function') {
            __this__[elem] = function(){
                _this[elem].apply(_this, arguments);
            };
        }
        else {
            var property = {};
            var originalProperty = Object.getOwnPropertyDescriptor(originalXMLHttpRequest, elem);
            property.get = function(){ return _this[elem]; };
            if (originalProperty.set) property.set = function(val){ return _this[elem] = val; };
            Object.defineProperty(__this__, elem, property);
        }
    });
    Object.keys(_this_proto).forEach(function(elem){
    	if (elem in __this__) return;
        if (elem === 'responseText') return;
        if (typeof _this[elem] === 'function') {
            if (elem === 'open') { // add requestURL support
                __this__[elem] = function(){
                    //console.log(elem, arguments);
                    if (arguments[1].indexOf('/enhance/player/') >= 0) {
                        // 对新版 api 请求旧的 api 接口
                        __this__.ping = new fakeXMLHttpRequest();
                        __this__.ping.open(arguments[0], arguments[1].replace('/enhance/player/url', '/detail'), false); // 不使用异步 xhr 以阻断原 xhr 请求
                        __this__.ping.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
                    }
                    _this[elem].apply(_this, arguments);
                    __this__.requestURL = arguments[1];
                    /*
                    if (arguments[1].indexOf('/enhance/player/')) {
                        arguments[1] = arguments[1].replace('/enhance/player/url', '/detail');
                    }*/
                };
            }
            else if (elem === 'send') { // add requestURL support
                __this__[elem] = function(){
                    //console.log(elem, arguments);
                    //console.log(__this__.ping);
                    if (__this__.requestURL.indexOf('/enhance/player/') >= 0 && __this__.ping) __this__.ping.send(arguments[0]);
                    _this[elem].apply(_this, arguments);
                };
            }
            else {
                __this__[elem] = function(){
                    //console.log(elem, arguments);
                    _this[elem].apply(_this, arguments);
                };
            }
        }
        else {
            var property = {};
            var originalProperty = Object.getOwnPropertyDescriptor(_this_proto, elem);
            property.get = function(){ /*console.log(elem);*/ return _this[elem]; };
            if (originalProperty.set) property.set = function(val){ return _this[elem] = val; };
            Object.defineProperty(__this__, elem, property);
        }
    });
    
    Object.defineProperty(__this__, 'responseText', {
        get: function(){
            //console.log(_this.responseText);
            //console.log('Request URL: ' + __this__.requestURL);
            try {
                if (__this__.requestURL.indexOf('/weapi/') < 0) return _this.responseText;
                var action = __this__.requestURL.split('/weapi/')[1].split('?')[0].split('/');
                switch (action[0]) {
                    case 'album':
                        var res = JSON.parse(_this.responseText);
                        modifyURL(res.album.songs);
                        return JSON.stringify(res);
                        break;
                    case 'song':
                        if (action[1] !== 'detail') {
                            if (action[1] !== 'enhance' && action[2] !== 'player' && action[3] !== 'url') return _this.responseText;
                            var res = JSON.parse(_this.responseText);
                            /*window.ping = __this__.ping;
                            console.log(__this__.ping);*/
                            if (__this__.ping) res.data[0].url = JSON.parse(__this__.ping.responseText).songs[0].mp3Url; // 替换旧版 api 的 url
                            return JSON.stringify(res);
                        }
                        var res = JSON.parse(_this.responseText);
                        modifyURL(res.songs);
                        return JSON.stringify(res);
                        break;
                    case 'playlist':
                        if (action[1] !== 'detail') return _this.responseText;
                        var res = JSON.parse(_this.responseText);
                        modifyURL(res.result.tracks);
                        return JSON.stringify(res);
                        break;
                    case 'dj':
                        if (action[2] === 'byradio') {
                            var res = JSON.parse(_this.responseText);
                            modifyURL(res.programs, 'mainSong');
                            return JSON.stringify(res);
                        }
                        else if (action[2] === 'detail') {
                            var res = JSON.parse(_this.responseText);
                            res.program = modifyURL([res.program], 'mainSong')[0];
                            return JSON.stringify(res);
                        }
                        else return _this.responseText;
                        break;
                    case 'v3':
                        switch (action[1]){
                            // http://music.163.com/weapi/v3/playlist/detail
                            case 'playlist':
                                if (action[2] !== 'detail') return _this.responseText;
                                var res = JSON.parse(_this.responseText);
                                res.privileges.forEach(function(elem){
                                    var q = elem.pl || elem.dl || elem.fl || Math.min(elem.maxbr, 320000) || 320000;
                                    elem.st = 0;
                                    elem.pl = q;
                                    elem.dl = q;
                                    elem.fl = q;
                                });
                                if (res.privileges.length < res.playlist.trackIds.length && res.playlist.trackIds.length === res.playlist.tracks.length) {
                                    // 对超过 1000 的播放列表补充播放信息（需魔改 core.js）
                                    for (var i = res.privileges.length; i < res.playlist.trackIds.length; i++) {
                                        var q = res.playlist.tracks.h ? res.playlist.tracks.h.br : res.playlist.tracks.m ? res.playlist.tracks.m.br : res.playlist.tracks.l ? res.playlist.tracks.l.br : res.playlist.tracks.a ? res.playlist.tracks.a.br : 320000;
                                        res.privileges.push({
                                            cp: 1,
                                            cs: false,
                                            dl: q,
                                            fee: 0,
                                            fl: q,
                                            id: res.playlist.trackIds[i].id,
                                            maxbr: q,
                                            payed: 0,
                                            pl: q,
                                            sp: 7,
                                            st: 0,
                                            subp: 1
                                        });
                                    }
                                }
                                //console.log(res);
                                return JSON.stringify(res);
                                break;
                            case 'song':
                                if (action[2] !== 'detail') return _this.responseText;
                                var res = JSON.parse(_this.responseText);
                                res.privileges.forEach(function(elem){
                                    var q = elem.pl || elem.dl || elem.fl || Math.min(elem.maxbr, 320000) || 320000;
                                    elem.st = 0;
                                    elem.pl = q;
                                    elem.dl = q;
                                    elem.fl = q;
                                });
                                return JSON.stringify(res);
                                break;
                            default:
                                return _this.responseText;
                        }
                        break;
                    default:
                        return _this.responseText;
                }
            }
            catch (error) {
                // 以防 api 转换失败也能正常返回数据
                console.error('转换出错！', error);
                return _this.responseText;
            }
        }
    });
    this.originalXMLHttpRequest = _this;
};
window.XMLHttpRequest = fakeXMLHttpRequest;