// ==UserScript==
// @name         【伟哥自用】脚本猫脚本站脚本下载助手
// @namespace    https://bbs.tampermonkey.net.cn/
// @version      0.0.2
// @description  在脚本猫code页和diff页下载源码 （哥哥，你也不想在下源码时安装脚本吧
// @author       朱焱伟
// @match        https://scriptcat.org/script-show-page/*
// @match        https://scriptcat.org/script-show-page/*/code
// @match        https://scriptcat.org/script-show-page/*/diff?version1=*&version2=*
// @exclude      https://scriptcat.org/script-show-page/*/comment
// @exclude      https://scriptcat.org/script-show-page/*/issue
// @icon         https://scriptcat.org/assets/logo.png
// @grant        GM_registerMenuCommand
// @grant        GM_unregisterMenuCommand
// ==/UserScript==

(function() {
    'use strict';
    class BaseDownloader {
        getM1code() {
            return monaco.editor.getModel("inmemory://model/1").getValue()
        }
        getScriptName() {
            return document.querySelector("a[href*='script-show-page']").textContent
        }
        download(filename, content, contentType) {
            if (!contentType) contentType = 'application/octet-stream';
            var a = document.createElement('a');
            var blob = new Blob([content], {
                'type': contentType
            });
            a.href = window.URL.createObjectURL(blob);
            a.download = filename;
            a.click();
        }
    }

    class DiffDownloader extends BaseDownloader{
        #scriptName;
        #v1Name;
        #v2Name;
        constructor() {
            super()
            if(this.isDiffPage()) {
                this.#scriptName = this.getScriptName()
                this.#v1Name = this.concatUserjsName(this.#scriptName,this.getVersions().v1)
                this.#v2Name = this.concatUserjsName(this.#scriptName,this.getVersions().v2)
            }
        }
        isDiffPage() {
            return window.location.pathname.search('diff') != -1
        }
        getv1leftcode() {
            return monaco.editor.getModel("inmemory://model/1").getValue()
        }
        getv2rightcode() {
            return monaco.editor.getModel("inmemory://model/2").getValue()
        }
        getVersions() {
        /* https://stackoverflow.com/questions/901115/how-can-i-get-query-string-values-in-javascript */
            const urlParams = new URLSearchParams(window.location.search)
            const paramv1 = urlParams.get('version1')
            const paramv2 = urlParams.get('version2')
            return {
                v1:paramv1,
                v2:paramv2
            }
        }
        concatUserjsName(codename,version){
            return codename + 'v' + version +'.user.js'
        }
        v1download() {
            if(this.isDiffPage()) {
                this.download(this.#v1Name,
                    monaco.editor.getModel("inmemory://model/1").getValue())
            }
        }
        v2download() {
            if(this.isDiffPage()) {
           /** https://stackoverflow.com/questions/56970253/ace-editor-cannot-read-property-getvalue-of-undefined 
            *  this作用域的问题
            */
            this.download(this.#v2Name,
                monaco.editor.getModel("inmemory://model/2").getValue())
            }
        }
    }

    class CodePageDownloader extends BaseDownloader{
        #userJsName;
        constructor(){
            super()
            if(this.isCodePage()){
                this.#userJsName = this.concatUserjsName()
            }
        }
        isCodePage() {
            return window.location.pathname.search('code') != -1
        }
        getScriptCode(){
            return this.getM1code()
        }
        concatUserjsName(){
            return this.getScriptName() + '.user.js'
        }
        scriptDownload(){
            if(this.isCodePage()){
                this.download(this.#userJsName,this.getScriptCode())
            }
        }
    }

    /** 
     * https://bbs.tampermonkey.net.cn/thread-1726-1-1.html
     * 如何做到当浏览器地址栏中的url变化后重新加载脚本？(出处: 油猴中文网)
     */
    function onRouterChange(callback){
        var _wr = function (type) {
            var orig = history[type];
            return function () {
                var rv = orig.apply(this, arguments);
                var e = new Event(type);
                e.arguments = arguments;
                window.dispatchEvent(e);
                return rv;
            };
        };
        history.pushState = _wr('pushState');
        window.addEventListener('pushState',callback);
    }

    var menu ={
        code:null,/* code页面菜单id */
        v1:null,  /* diff页面version1菜单id */
        v2:null   /* diff页面version2菜单id */
    }

    function flushMenu(){
        const flushMenuByid = (menu_id) =>{
            if(menu_id){
                GM_unregisterMenuCommand(menu_id)
            }
        }
        flushMenuByid(menu.v1)
        flushMenuByid(menu.v2)
        flushMenuByid(menu.code)
        Object.keys(menu).forEach(key=>{menu[key]=null})
        /* menu.v1等一个个用=null的方式经测试不能改变其值 */
    }

    function addDownloadMenu(){
        /* 分别在code页面和diff页面添加菜单，下载代码 */
        if (window.location.pathname.search('code') != -1) {// code
            menu.code = GM_registerMenuCommand ("点我下载Code页代码", function(){
                let codePageDownloader = new CodePageDownloader()
                codePageDownloader.scriptDownload()
            },'code');
        }
        if (window.location.pathname.search('diff') != -1) {// diff
            let diffDownloader = new DiffDownloader()
            if (menu.v1 == null) {
                menu.v1 = GM_registerMenuCommand ("点我下载左侧代码",()=>{
                    diffDownloader.v1download()
                },'version1');
            }
            if (menu.v2 == null) {
                menu.v2 = GM_registerMenuCommand ("点我下载右侧代码",()=>{
                    diffDownloader.v2download()
                },'version2');
            }
        }
    }

    addDownloadMenu() /* match时添加菜单 */
    onRouterChange( () => { /* 若路由发生改变，销毁菜单后再建 */
        flushMenu() /* console.log("flush之后Menu内部元素:"+menu.v1+menu.v2+menu.code) */
        addDownloadMenu()
    })
    // Your code here...
})();
/**
 * code页测试地址 https://scriptcat.org/script-show-page/513/code
 * diff页测试地址 https://scriptcat.org/script-show-page/57/diff?version1=66.93&version2=66.92
 */