// ==UserScript==
// @name        网易云音乐直接下载
// @namespace   https://www.ocrosoft.com/
// @description 在单曲页面显示歌词、翻译、封面、歌曲下载链接并以高音质试听，同时支持歌单、专辑、等页面直接下载单曲。该脚本受 GPL V2.0 许可证保护。脚本仍在测试，如遇到错误，请反馈网址。
// @match       *://music.163.com/*
// @grant       GM_xmlhttpRequest
// @version     2.0
// @downloadURL none
// ==/UserScript==
/**
 * 修改自 https://greasyfork.org/zh-CN/scripts/10548-%E7%BD%91%E6%98%93%E4%BA%91%E9%9F%B3%E4%B9%90%E4%B8%8B%E8%BD%BD
 * API 源码: https://github.com/Ocrosoft/NetEase_OutChain
 * 此脚本开源，API开源，但请不要在未经允许的情况下在其他程序中调用此脚本中的API，在非程序调用且小流量的个人使用场景下可以使用。
**/

/**
 *
 */

(function(root) {
    'use strict';
    /*
     * @opentdoor 的跨域下载接口
     */
    function Downloader() {
        // request
        function FileRequest(url, progress, callback) {
            var req = GM_xmlhttpRequest({
                method: 'GET',
                url: url,
                onprogress: function(res) {
                    if (progress) progress(res);
                },
                overrideMimeType: "text/plain;charset=x-user-defined",
                onreadystatechange: function(res) {
                    if (res.readyState == 4) {
                        if (res.status == 200) {
                            var str = res.response;
                            var ta1 = [];
                            for (var i = 0; i < str.length; i++) {
                                ta1[i] = str.charCodeAt(i) & 0x00ff;
                            }
                            var ua8 = new Uint8Array(ta1);
                            var blob = new Blob([ua8]);
                            callback(blob, res.status);
                        } else {
                            callback(null, res.status);
                        }
                    }
                }
            });
        }
        //save file
        function SaveFile(blob, filename) {
            if (root.navigator.msSaveBlob) {
                root.navigator.msSaveBlob(blob, filename);
            } else {
                var anchor = root.document.createElement('a');
                var url = root.URL.createObjectURL(blob);
                anchor.download = filename;
                anchor.href = url;
                var evt = root.document.createEvent("MouseEvents");
                evt.initEvent("click", true, true);
                anchor.dispatchEvent(evt);
                root.URL.revokeObjectURL(url);
            }
        }
        //interface
        function FileDownload(url, filename, downloading, success, error) {
            FileRequest(url, downloading,
                        function(blob, status) {
                if (status == 200) {
                    SaveFile(blob, filename);
                    if (typeof success == 'function') success();
                } else {
                    if (typeof error == 'function') error(status);
                }
            });
        }
        this.FileDownload = FileDownload;
        var anthorEvents = {
            onprogress: function(res) {
                if (this.anchor.getAttribute('data-res-action') == 'downloadDirect') {
                    if (res.lengthComputable) {
                        this.anchor.querySelector('i').innerText = '下载:' + (res.loaded * 100 / res.total).toFixed(2) + '%';
                    } else {
                        this.anchor.querySelector('i').innerText = '下载:' + anthorEvents.calcLength(res.loaded);
                    }
                } else {
                    if (res.lengthComputable) {
                        this.anchor.innerText = '下载:' + (res.loaded * 100 / res.total).toFixed(2) + '%';
                    } else {
                        this.anchor.innerText = "下载:" + anthorEvents.calcLength(res.loaded);
                    }
                }
            },
            calcLength: function(b) {
                b = Number(b) / 1024;
                if (b < 1024) {
                    return b.toFixed(1) + "KB";
                }
                b = b / 1024;
                if (b < 1024) {
                    return b.toFixed(2) + "MB";
                }
                b = b / 1024;
                return b.toFixed(3) + "GB";
            },
            onsuccess: function() {
                this.anchor.innerHTML = this.Html;
                this.doing = false;
                if (this.anchor.id == 'tmp') {
                    this.anchor.previousElementSibling.remove();
                    this.anchor.remove();
                }
            },
            onerror: function() {
                this.anchor.innerHTML = "下载失败";
                this.handler = setTimeout(function(t) {
                    t.anchor.innerHTML = t.Html;
                    t.doing = false;
                },
                                          2000, this);
            },
            onAnthorClick: function(e) {
                e = e || event;
                var a = this.anchor;
                var ex = /([\w\s]+)(\.\w)(\?.*)?$/i.exec(a.href || "");
                var name = a.download || a.title;
                if (ex) {
                    if (!name && ex.length > 1) name = ex[1];
                    if (name && name.indexOf('.') == -1 && ex.length > 2) name += ex[2];
                }
                if (!name || !a.href) return;
                e.preventDefault();
                if (this.doing) return;
                this.doing = true;
                FileDownload(a.href, name, anthorEvents.onprogress.bind(this), anthorEvents.onsuccess.bind(this), anthorEvents.onerror.bind(this));
            }
        };
        //interface
        function BindAnthor(a) {
            var env = {
                Html: a.innerHTML,
                anchor: a
            };
            a.addEventListener('click', anthorEvents.onAnthorClick.bind(env), true);
        }
        this.BindAnthor = BindAnthor;
    }

    var downloader = new Downloader();

    var api = {

        detailUrl: function(songIds) {
            var tpl = (location.href.indexOf('https') == -1 ? 'http://music.ocrosoft.com/GetMusicLinkt.php?id=${songIds}': 'https://www.ocrosoft.com/outchain/GetMusicLinkt.php?id=${songIds}');

            return tpl.replace('${songIds}', songIds.join(','));
        },

        detail: function(songIds, callback, username=null, password=null) {
            var script = document.createElement('script');
            script.innerHTML = 'var returnMusicData;';
            document.body.appendChild(script);
            returnMusicData = function(data) {
                callback(data);
            };
            script = document.createElement('script');
            var url = this.detailUrl(songIds) + '&callback=returnMusicData';
            if(username) url += '&username=' + username + '&password=' + password;
            script.setAttribute('src', url);
            document.body.appendChild(script);
        },

        mediaUrl: function(songId) {
            return (location.href.indexOf('https') == -1 ? 'http': 'https') + '://music.163.com/api/song/lyric?os=pc&id=' + songId + '&lv=-1&kv=-1&tv=-1';
        },

        media: function(songId, callback) {
            var req = new XMLHttpRequest();
            req.open('GET', this.mediaUrl(songId), true);
            req.onload = function() {
                callback(JSON.parse(this.responseText));
            };
            req.send();
        },

    };

    var innerFrame = document.querySelector('iframe');
    var tit, cov, dl;
    var fileName;

    var pages = [{
        url: 'http://music.163.com/#/song?id=',
        handler: function() {
            var innerFrameDoc = innerFrame.contentWindow.document;
            var albumNode = innerFrameDoc.querySelectorAll('p.des.s-fc4')[1];
            tit = innerFrameDoc.querySelector('.tit');
            cov = innerFrameDoc.querySelector('.u-cover').querySelector('img');
            dl = innerFrameDoc.querySelector('.u-btni-dl');
            fileName = tit.querySelector('.f-ff2').innerText + ' - ' + tit.parentNode.nextElementSibling.querySelector('.s-fc7').innerText + '.';
            var parentNode = albumNode.parentNode;

            var songId = location.href.match(/id=([0-9]+)/)[1];
            var downloadLine = this.createDownloadLine(songId);

            parentNode.insertBefore(downloadLine, albumNode.nextElementSibling);
        },
        createDownloadLine: function(songId) {
            var disableStyle = function(link) {
                link.text += '(无)';
                link.style.color = 'gray';
                link.style.textDecoration = 'none';
                link.style.cursor = 'auto';
            };

            var mp3Link = this.createMP3Link();
            var lyricLink = this.createLink('歌词');
            var tlyricLink = this.createLink('翻译');
            var coverLink = this.createLink('封面');
            var mp3Help = this.createLink('如何下载歌曲?');
            var showPlayer = this.createLink('高音质试听');

            mp3Help.addEventListener('click',
                                     function() {
                alert("点击下方的下载按钮之后等待即可。");
            });
            showPlayer.addEventListener('click',
                                        function() {
                var player = innerFrame.contentWindow.document.querySelector('#wyyyydda');
                player.setAttribute('controls', 'true');
                player.play();
            });
            lyricLink.setAttribute('download', fileName + 'lrc');
            tlyricLink.setAttribute('download', fileName.substring(0, fileName.length - 1) + '(翻译).lrc');
            coverLink.setAttribute('download', fileName + 'jpg');
            coverLink.href = cov.getAttribute('data-src');
            downloader.BindAnthor(coverLink);
            downloader.BindAnthor(dl);
            dl.href = 'javascript:;';
            dl.setAttribute('data-res-action', 'downloadDirect');
            dl.querySelector('i').innerText = '下载(稍候)';

            api.detail([songId],
                       function(result) {
                mp3Link.src = result.mp3Url;
            });
            api.media(songId,
                      function(result) {
                if (result.lrc && result.lrc.lyric) {
                    lyricLink.href = 'data:text/plain;charset=utf-8,' + encodeURIComponent(result.lrc.lyric);
                } else {
                    disableStyle(lyricLink);
                }
                if (result.tlyric && result.tlyric.lyric) {
                    tlyricLink.href = 'data:text/plain;charset=utf-8,' + encodeURIComponent(result.tlyric.lyric);
                } else {
                    disableStyle(tlyricLink);
                }
            });

            var container = this.createLineContainer('下载');
            container.appendChild(lyricLink); // 原文lrc
            container.appendChild(tlyricLink); // 翻译lrc
            container.appendChild(coverLink); // 封面
            container.appendChild(mp3Help); // 帮助
            container.appendChild(showPlayer); // 试听
            container.appendChild(document.createElement('br'));
            container.appendChild(mp3Link); // audio标签
            return container;
        },
        createLink: function(label) {
            var link = document.createElement('a');
            link.innerHTML = label;
            link.className = 's-fc7';
            link.style.marginRight = '10px';
            link.href = 'javascript:;';
            return link;
        },
        createMP3Link: function() {
            var link = document.createElement('audio');
            link.setAttribute('id', 'wyyyydda');
            link.style.marginTop = '10px';
            link.addEventListener('canplay',
                                  function() {
                dl.href = this.src;
                dl.setAttribute('download', fileName + 'mp3');
                dl.querySelector('i').innerText = '下载';
            });
            link.addEventListener('error',
                                  function() {
                    var username = prompt('无法加载歌曲。付费歌曲请输入会员手机号');
                    if(username !== null){
                        var password = prompt('请输入密码。（不会记录，仅用于模拟登陆）');
                        var _self = this;
                        if(password !== null){
                            api.detail([location.href.match(/id=([0-9]+)/)[1]],
                                       function(result) {
                                _self.src = result.mp3Url;
                            }, username, password);
                        }
                    }
                dl.querySelector('i').innerText = '下载';
            });
            return link;
        },
        createLineContainer: function(label) {
            var container = document.createElement('p');
            container.className = 'desc s-fc4';
            container.innerHTML = label + '：';
            container.style.margin = '10px 0';
            return container;
        },
    },
                 {
                     url: ['http://music.163.com/#/playlist?id=', // 歌单
                           'http://music.163.com/#/artist?id=', // 歌手
                           'http://music.163.com/#/discover/toplist', // 榜单
                           'http://music.163.com/#/album?id=', // 专辑
                           'http://music.163.com/#/discover/recommend/taste' // 每日推荐
                          ],
                     handler: function() {
                         var innerFrameDoc = innerFrame.contentWindow.document;
                         var downloadButtons = (innerFrameDoc).querySelectorAll('span.icn-dl');

                         this.replaceAction(innerFrameDoc, downloadButtons);
                     },
                     replaceAction: function(innerFrameDoc, downloadButtons) {
                         for (var i = 0; i < downloadButtons.length; i++) {
                             if (downloadButtons[i].getAttribute('data-res-action') == 'download') {
                                 downloadButtons[i].setAttribute('data-res-action', 'downloadDirect');
                                 downloadButtons[i].addEventListener('click',
                                                                     function() {
                                     var id = this.getAttribute('data-res-id');
                                     var ele = this;
                                     var nameAndAuthor = this.previousElementSibling.getAttribute('data-res-name') + ' - ' + this.previousElementSibling.getAttribute('data-res-author');
                                     api.detail([id],
                                                function(res) {
                                         var audio = document.createElement('audio');
                                         audio.setAttribute('src', res.mp3Url);
                                         audio.setAttribute('id', 'wyyyydda');
                                         audio.addEventListener('canplay',
                                                                function() {
                                             var a = document.createElement('a');
                                             a.setAttribute('href', this.src);
                                             a.setAttribute('download', nameAndAuthor + '.mp3');
                                             a.setAttribute('id', 'tmp');
                                             downloader.BindAnthor(a);
                                             ele.parentNode.appendChild(document.createElement('br'));
                                             ele.parentNode.appendChild(a);
                                             a.click();
                                         });

                                         audio.addEventListener('error',
                                                                function() {
                                             var _id = id;
                                             var username = prompt('无法加载歌曲。付费歌曲请输入会员手机号。');
                                             if(username !== null){
                                                 var password = prompt('请输入密码。（不会记录，仅用于模拟登陆）');
                                                 var _self = this;
                                                 if(password !== null){
                                                     api.detail([_id],
                                                                function(result) {
                                                         _self.src = result.mp3Url;
                                                     }, username, password);
                                                 }
                                             }
                                         });
                                     });
                                 });
                             }
                         }
                     }
                 },
                ];

    function matchPagesURL(href, urls) {
        var ret = false;
        var t = location.href.split('://')[1];
        if (Array.isArray(urls)) {
            urls.forEach(function(ele) {
                if (t.indexOf(ele.split('://')[1]) === 0) {
                    ret = true;
                    return;
                }
            });
        } else {
            if (t.indexOf(urls.split('://')[1]) === 0) {
                ret = true;
            }
        }
        return ret;
    }

    if (innerFrame) {
        innerFrame.addEventListener('load',
                                    function() {
            var i, page;
            for (i = 0; i < pages.length; i += 1) {
                page = pages[i];
                if (matchPagesURL(location.href, page.url)) {
                    page.handler();
                }
            }
        });
    }
})(window);