misc/ebrowser/webview.js

   1 /* Copyright (C) 2024 Richard Hao Cao
   2 Ebrowser is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
   3
   4 Ebrowser is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
   5
   6 You should have received a copy of the GNU General Public License along with this program. If not, see <https://www.gnu.org/licenses/>.
   7 */
   8 const {
   9   app, BrowserWindow, Menu, shell, clipboard,
  10   session, protocol, net, dialog, ipcMain
  11 } = require('electron')
  12 let win;
  13
  14 if(!app.requestSingleInstanceLock())
  15   app.quit()
  16 else {
  17   app.on('ready', createWindow);
  18   app.on('second-instance', (event, args, cwd) => {
  19     if (win) {
  20       if (win.isMinimized()) {
  21         win.restore()
  22       }
  23       win.show()
  24       win.focus()
  25       cmdlineProcess(args,cwd,1);
  26     }else
  27       createWindow();
  28   })
  29 }
  30 Menu.setApplicationMenu(null);
  31 const fs = require('fs');
  32 const path = require('path')
  33 var translateRes;
  34 {
  35   let langs = app.getPreferredSystemLanguages();
  36   if(langs.length==0 || langs[0].startsWith('en'))
  37     topMenu();
  38   else
  39     initTranslateRes(langs[0]);
  40 }
  41
  42 var repositoryurl = "https://gitlab.com/jamesfengcao/uweb/-/raw/master/misc/ebrowser/";
  43 const readline = require('readline');
  44 const process = require('process')
  45 var gredirects = [];
  46 var gredirect;
  47 var redirects;
  48 var bRedirect = true;
  49 var bJS = true;
  50 var bForwardCookie = false;
  51 var proxies = {};
  52 var proxy;
  53 var useragents = {};
  54 var downloadMenus; //[]
  55 var selectMenus = [];
  56 var defaultUA =
  57     "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/" +
  58     process.versions.chrome +" Safari/537.36";
  59 app.userAgentFallback = defaultUA;
  60
  61 fs.readFile(path.join(__dirname,'redirect.json'), 'utf8', (err, jsonString) => {
  62   if (err) return;
  63   try {
  64     redirects = JSON.parse(jsonString);
  65   } catch (e){console.log(e)}
  66 });
  67
  68 async function createWindow () {
  69   try {
  70     let json = await fs.promises.readFile(path.join(__dirname,'uas.json'), 'utf8');
  71     useragents = JSON.parse(json);
  72   } catch (e){console.log(e)}
  73
  74   protocol.handle("i",(req)=>{return null;});
  75   await (async ()=>{
  76     try{
  77       const readInterface = readline.createInterface ({
  78         input: fs.createReadStream (path.join(__dirname,'config'), 'utf8'),
  79       });
  80
  81       for await (const line of readInterface) {
  82         addrCommand(line);
  83       }
  84     }catch(e){console.log(e);}
  85   })();
  86
  87   win = new BrowserWindow(
  88     {width: 800, height: 600,autoHideMenuBar: true,
  89      webPreferences: {
  90        nodeIntegration: true,
  91        contextIsolation: false,
  92        webviewTag: true,
  93      }});
  94   win.setMenuBarVisibility(false);
  95   win.on('closed', function () {
  96     win = null
  97   })
  98
  99   win.loadFile('index.html');
 100   fs.readFile(path.join(__dirname,'gredirect.json'), 'utf8', (err, jsonString) => {
 101     if (err) return;
 102     try {
 103       gredirects = JSON.parse(jsonString);
 104     } catch (e){console.log(e)}
 105   });
 106
 107   fs.readFile(path.join(__dirname,'proxy.json'), 'utf8', (err, jsonString) => {
 108     if (err) return;
 109     try {
 110       proxies = JSON.parse(jsonString, (key,val)=>{
 111         if(!proxy && key==="proxyRules"){
 112           proxy = {proxyRules:val};
 113         }
 114         return val;
 115       });
 116     } catch (e){console.log(e)}
 117   });
 118
 119   cmdlineProcess(process.argv, process.cwd(), 0);
 120   //app.commandLine.appendSwitch ('trace-warnings');
 121
 122   fs.readFile(path.join(__dirname,'download.json'), 'utf8', (err, jsonStr) => {
 123     if (err) return;
 124     try {
 125       downloadMenus = JSON.parse(jsonStr);
 126     }catch (e){console.log(e)}
 127   });
 128
 129   fs.readFile(path.join(__dirname,'select.json'), 'utf8', (err, jsonStr) => {
 130     if (err) return;
 131     try {
 132       selectMenus = JSON.parse(jsonStr);
 133     }catch (e){console.log(e)}
 134   });
 135
 136   win.webContents.on('page-title-updated',(event,cmd)=>{
 137     addrCommand(cmd);
 138   });
 139
 140   session.defaultSession.on("will-download", (e, item) => {
 141     //item.setSavePath(save)
 142     if(!downloadMenus) return;
 143     let buttons = ["OK", "Cancel", translate("Copy")];
 144     buttons.push(downloadMenus.filter((item, index) => (index&1) === 0));
 145     const button = dialog.showMessageBoxSync(win, {
 146       "type": "question",
 147       "title": translate("Download"),
 148       "message":  `Do you want to download the file?`,
 149       "buttons": buttons,
 150       "defaultId": 0,
 151     });
 152     switch(button) {
 153     case 0:
 154       return;
 155     case 1:
 156       break;
 157     case 2:
 158       clipboard.writeText(item.getURL());
 159       break;
 160     default:
 161       let cmd = downloadMenus[2*button-5].replace('%u',item.getURL());
 162       let js = `handleQueries(\`${cmd}\`)`;
 163       win.webContents.executeJavaScript(js,false);
 164     }
 165     e.preventDefault();
 166   });
 167
 168   win.webContents.on('console-message',cbConsoleMsg);
 169 }
 170
 171 app.on('window-all-closed', function () {
 172   app.quit()
 173 })
 174
 175 app.on('activate', function () {
 176   if (win === null) {
 177     createWindow()
 178   }
 179 })
 180
 181 app.on('will-quit', () => {
 182 })
 183
 184 app.on ('web-contents-created', (event, contents) => {
 185   if (contents.getType () === 'webview') {
 186     contents.setWindowOpenHandler(cbWindowOpenHandler);
 187     contents.on('context-menu',onContextMenu);
 188     contents.on('page-title-updated',cbTitleUpdate);
 189     contents.session.webRequest.onBeforeRequest(interceptRequest);
 190   }
 191 });
 192
 193 ipcMain.on('command', (event, cmd) => {
 194   addrCommand(cmd);
 195 });
 196
 197 function addrCommand(cmd){
 198   if(cmd.length<3) return;
 199   let c0 = cmd.charCodeAt(0);
 200   switch(c0){
 201   case 58: //':'
 202     args = cmd.substring(1).split(/\s+/);
 203     switch(args[0]){
 204     case "cert":
 205       if(args.length==1)
 206         session.defaultSession.setCertificateVerifyProc((request, callback) => {
 207           callback(0);
 208         });
 209       else
 210         session.defaultSession.setCertificateVerifyProc(null);
 211       return;
 212     case "clear":
 213       if(args.length==1){
 214         session.defaultSession.clearData();
 215         return;
 216       }
 217       switch(args[1]){
 218       case "cache":
 219         session.defaultSession.clearCache();
 220         return;
 221       case "dns":
 222         session.defaultSession.clearHostResolverCache();
 223         return;
 224       case "storage":
 225         session.defaultSession.clearStorageData();
 226         return;
 227       default:
 228         try {
 229           let opts = JSON.parse(args.slice(1).join(""));
 230           session.defaultSession.clearData(opts);
 231         }catch(e){console.log(e)}
 232       }
 233       return;
 234     case "ext":
 235       session.defaultSession.loadExtension(args[1]);
 236       return;
 237     case "gr":
 238       if(args.length<2) {
 239         gredirect_enable(0);
 240         return;
 241       }
 242       let i = parseInt(args[1]);
 243       if(i>=0 && i<gredirects.length)
 244         gredirect_enable(i);
 245       else
 246         gredirect_disable();
 247       return;
 248     case "js"://execute js
 249       eval(cmd.slice(4));
 250       return;
 251     case "nc":
 252       bForwardCookie = false;
 253       msgbox_info("Cookie forwarding disabled");
 254       return;
 255     case "uc":
 256       if(bForwardCookie) {
 257         msgbox_info("Cookie forwarding enabled for global redirection");
 258         return;
 259       }
 260       forwardCookie();
 261       return;
 262     case "np":
 263       session.defaultSession.setProxy ({mode:"direct"});
 264       bRedirect = true;
 265       return;
 266     case "up":
 267       if(args.length>1)
 268         proxy = proxies[args[1]]; //retrieve proxy
 269       if(proxy){
 270         gredirect_disable();
 271         session.defaultSession.setProxy(proxy);
 272       }
 273       return;
 274     case "nr":
 275       bRedirect = false; return;
 276     case "ur":
 277       bRedirect = true; return;
 278     case "ua":
 279       if(args.length==2)
 280         session.defaultSession.setUserAgent(useragents[args[1]]);
 281       else
 282         session.defaultSession.setUserAgent(defaultUA);
 283       return;
 284     case "update":
 285       let updateurl;
 286       if(1==args.length)
 287         updateApp(repositoryurl);
 288       else {
 289         filename = args[1];
 290         let iSlash = filename.lastIndexOf('/');
 291         if(iSlash>0){
 292           let folder = path.join(__dirname,filename.substring(0,iSlash));
 293           fs.mkdirSync(folder,{ recursive: true });
 294         }
 295         fetch2file(repositoryurl,filename);
 296       }
 297       return;
 298     }
 299   }
 300 }
 301
 302 function gredirect_disable(){
 303   if(gredirect){
 304     gredirect=null;
 305     unregisterHandler();
 306   }
 307   bRedirect = false;
 308 }
 309 function gredirect_enable(i){
 310   if(i>=gredirects.length) return;
 311   if(!gredirect) registerHandler();
 312   gredirect=gredirects[i];
 313 }
 314
 315 function cbConsoleMsg(e, level, msg, line, sourceid){
 316   console.log(line);
 317   console.log(sourceid);
 318   console.log(msg);
 319 }
 320
 321 function interceptRequest(details, callback){
 322   let url = details.url;
 323   if(58===url.charCodeAt(1) || (!bJS && url.endsWith(".js"))){
 324     callback({ cancel: true });
 325     return;
 326   }
 327   do {
 328     if(gredirect || !bRedirect ||(details.resourceType !== 'mainFrame' &&
 329                      details.resourceType !== 'subFrame')) break;
 330     let oURL = new URL(url);
 331     let domain = oURL.hostname;
 332     let newUrl;
 333     try{
 334       let newDomain = redirects[domain];
 335       if(!newDomain) break;
 336       newUrl = "https://"+newDomain+oURL.pathname+oURL.search+oURL.hash;
 337     }catch(e){break;}
 338     callback({ cancel: false, redirectURL: newUrl });
 339     return;
 340   }while(false);
 341   callback({ cancel: false });
 342 }
 343
 344 function cbWindowOpenHandler(details){
 345   let url = details.url;
 346   let js = "newTab();tabs.children[tabs.children.length-1].src='"+
 347       url+"';";
 348   switch(details.disposition){
 349   case "foreground-tab":
 350   case "new-window":
 351     js = js + "switchTab(tabs.children.length-1)";
 352   }
 353   win.webContents.executeJavaScript(js,false);
 354   return { action: "deny" };
 355 }
 356 function cbTitleUpdate(event,title){
 357   win.setTitle(title);
 358 }
 359 function menuSelection(menuTemplate, text){
 360   for(let i=0; i<selectMenus.length-1;i++){
 361     menuTemplate.push({
 362       label: selectMenus[i],
 363       click: () => {
 364         let cmd = selectMenus[i+1].replace('%s',text);
 365         let js = `handleQueries(\`${cmd}\`)`;
 366         win.webContents.executeJavaScript(js,false);
 367       }
 368     });
 369   }
 370 }
 371 function menuArray(labelprefix, linkUrl){
 372   let menuTemplate = [
 373     {
 374       label: labelprefix+translate('Open'),
 375       click: () => {
 376         shell.openExternal(linkUrl);
 377       }
 378     },
 379     {
 380       label: labelprefix+translate('Copy'),
 381       click: () => {
 382         clipboard.writeText(linkUrl);
 383       }
 384     },
 385     {
 386       label: labelprefix+translate('Download'),
 387       click: () => {
 388         win.contentView.children[i].webContents.downloadURL(linkUrl);
 389       }
 390     },
 391   ];
 392   if(downloadMenus){
 393     for(let i=0; i<downloadMenus.length-1;i++){
 394       menuTemplate.push({
 395         label: labelprefix+downloadMenus[i],
 396         click: () => {
 397           let cmd = downloadMenus[i+1].replace('%u',linkUrl);
 398           let js = `handleQueries(\`${cmd}\`)`;
 399           win.webContents.executeJavaScript(js,false);
 400         }
 401       });
 402     }
 403   }
 404   return menuTemplate;
 405 }
 406
 407 function onContextMenu(event, params){
 408   let url = params.linkURL;
 409   let mTemplate = [];
 410   if (url) {
 411     mTemplate.push({label:url,enabled:false});
 412     mTemplate.push.apply(mTemplate,menuArray("",url));
 413     if((url=params.srcURL))
 414       mTemplate.push.apply(mTemplate,menuArray("src: ",url));
 415   }else if((url=params.srcURL)){
 416     mTemplate.push({label:url,enabled:false});
 417     mTemplate.push.apply(mTemplate,menuArray("src: ",url));
 418   }else if((url=params.selectionText)){
 419     menuSelection(mTemplate,url);
 420   }else
 421     return;
 422
 423   const contextMenu = Menu.buildFromTemplate(mTemplate);
 424   contextMenu.popup();
 425 }
 426
 427 async function topMenu(){
 428   const menuTemplate = [];
 429   try {
 430     let json = await fs.promises.readFile(path.join(__dirname,'menu.json'), 'utf8');
 431     let menus = JSON.parse(json);
 432     if(menus.length>1){
 433       let submenu = [];
 434       for(let i=0;i<menus.length-1; i=i+2){
 435         let cmd = menus[i+1];
 436         let js = `handleQueries("${cmd}")`;
 437         submenu.push({
 438           label: menus[i], click: ()=>{
 439             win.webContents.executeJavaScript(js,false);
 440           }});
 441       }
 442       menuTemplate.push({
 443         label: translate('Tools'),
 444         submenu: submenu,
 445       });
 446     }
 447   }catch(e){console.log(e)}
 448   menuTemplate.push(
 449     {
 450       label: translate('Edit'),
 451       submenu: [
 452         { label: translate('Config folder'), click: ()=>{
 453           shell.openPath(__dirname);
 454         }},
 455       ]
 456     },
 457     {
 458       label: translate('Help'),
 459       submenu: [
 460         { label: translate('Check for updates'), click: ()=>{
 461           addrCommand(":update");
 462         }},
 463         { label: translate('Help'), accelerator: 'F1', click: ()=>{
 464           help();
 465         }},
 466         { label: translate('Stop'), accelerator: 'Ctrl+C', click: ()=>{
 467           let js="tabs.children[iTab].stop()"
 468           win.webContents.executeJavaScript(js,false)
 469         }},
 470         { label: translate('getURL'), accelerator: 'Ctrl+G', click: ()=>{
 471           let js="{let q=document.forms[0].q;q.focus();q.value=tabs.children[iTab].getURL()}"
 472           win.webContents.executeJavaScript(js,false)
 473         }},
 474         { label: translate('Select'), accelerator: 'Ctrl+L', click:()=>{
 475           win.webContents.executeJavaScript("document.forms[0].q.select()",false);
 476         }},
 477         { label: translate('New Tab'), accelerator: 'Ctrl+T', click:()=>{
 478           let js = "newTab();document.forms[0].q.select();switchTab(tabs.children.length-1)";
 479           win.webContents.executeJavaScript(js,false);
 480         }},
 481         { label: translate('Restore Tab'), accelerator: 'Ctrl+Shift+T', click:()=>{
 482           let js = "{let u=closedUrls.pop();if(u){newTab();switchTab(tabs.children.length-1);tabs.children[iTab].src=u}}";
 483           win.webContents.executeJavaScript(js,false);
 484         }},
 485         { label: translate('No redirect'), accelerator: 'Ctrl+R', click: ()=>{
 486           gredirect_disable();
 487         }},
 488         { label: translate('Redirect'), accelerator: 'Ctrl+Shift+R', click: ()=>{
 489           gredirect_enable(0);
 490         }},
 491         { label: translate('Close tab'), accelerator: 'Ctrl+W', click: ()=>{
 492           win.webContents.executeJavaScript("tabClose()",false).then((r)=>{
 493             if(""===r) win.close();
 494             else win.setTitle(r);
 495           });
 496         }},
 497         { label: translate('Next Tab'), accelerator: 'Ctrl+Tab', click: ()=>{
 498           let js="tabInc(1);getWinTitle()";
 499           win.webContents.executeJavaScript(js,false).then((r)=>{
 500             win.setTitle(r);
 501           });
 502         }},
 503         { label: translate('Previous Tab'), accelerator: 'Ctrl+Shift+Tab', click: ()=>{
 504           let js="tabDec(-1);getWinTitle()";
 505           win.webContents.executeJavaScript(js,false).then((r)=>{
 506             win.setTitle(r);
 507           });
 508         }},
 509         { label: translate('Go backward'), accelerator: 'Alt+Left', click: ()=>{
 510           let js="tabs.children[iTab].goBack()";
 511           win.webContents.executeJavaScript(js,false);
 512         }},
 513         { label: translate('Go forward'), accelerator: 'Alt+Right', click: ()=>{
 514           let js="tabs.children[iTab].goForward()";
 515           win.webContents.executeJavaScript(js,false);
 516         }},
 517         { label: translate('Zoom in'), accelerator: 'Ctrl+Shift+=', click: ()=>{
 518           let js="{let t=tabs.children[iTab];let s=t.getZoomFactor()*1.2;t.setZoomFactor(s)}";
 519           win.webContents.executeJavaScript(js,false);
 520         }},
 521         { label: translate('Zoom out'), accelerator: 'Ctrl+-', click: ()=>{
 522           let js="{let t=tabs.children[iTab];let s=t.getZoomFactor()/1.2;t.setZoomFactor(s)}";
 523           win.webContents.executeJavaScript(js,false);
 524         }},
 525         { label: translate('Default zoom'), accelerator: 'Ctrl+0', click: ()=>{
 526           let js="tabs.children[iTab].setZoomFactor(1)";
 527           win.webContents.executeJavaScript(js,false);
 528         }},
 529         { label: translate('No focus'), accelerator: 'Esc', click: ()=>{
 530           let js = `{let e=document.activeElement;
 531 if(e)e.blur();try{tabs.children[iTab].stopFindInPage('clearSelection')}catch(er){}}`;
 532           win.webContents.executeJavaScript(js,false);
 533         }},
 534         { label: translate('Reload'), accelerator: 'F5', click: ()=>{
 535           win.webContents.executeJavaScript("tabs.children[iTab].reload()",false);
 536         }},
 537         { label: translate('Devtools'), accelerator: 'F12', click: ()=>{
 538           let js = "try{tabs.children[iTab].openDevTools()}catch(e){console.log(e)}";
 539           win.webContents.executeJavaScript(js,false);
 540         }},
 541
 542       ],
 543     },
 544   );
 545   const menu = Menu.buildFromTemplate(menuTemplate);
 546   Menu.setApplicationMenu(menu);
 547 }
 548
 549 function cmdlineProcess(argv,cwd,extra){
 550   let i1st = 2+extra; //index for the first query item
 551   if(argv.length>i1st){
 552     if(i1st+1==argv.length){//local file
 553       let fname =  path.join(cwd, argv[i1st]);
 554       if(fs.existsSync(fname)){
 555         let js = "tabs.children[iTab].src='file://"+fname+"'";
 556         win.webContents.executeJavaScript(js,false);
 557         win.setTitle(argv[i1st]);
 558         return;
 559       }
 560     }
 561     let url=argv.slice(i1st).join(" ");
 562     win.webContents.executeJavaScript("handleQuery(`"+url+"`)",false);
 563     win.setTitle(url);
 564   }
 565 }
 566
 567 async function cbScheme_redir(req){
 568   if(!gredirect) return null;
 569   let oUrl = req.url;
 570   let newurl = gredirect+oUrl;
 571   let options = {
 572     body:       req.body,
 573     headers:    req.headers,
 574     method:     req.method,
 575     referer:    req.referer,
 576     duplex: "half",
 577     bypassCustomProtocolHandlers: true
 578   };
 579   if(bForwardCookie){
 580     let cookies = await session.defaultSession.cookies.get({url: oUrl});
 581     let cookieS = cookies.map (cookie => cookie.name  + '=' + cookie.value ).join(';');
 582     options.headers['Cookie'] = cookieS;
 583   }
 584
 585   return fetch(newurl, options);
 586 }
 587
 588 function registerHandler(){
 589   protocol.handle("http",cbScheme_redir);
 590   protocol.handle("https",cbScheme_redir);
 591   protocol.handle("ws",cbScheme_redir);
 592   protocol.handle("wss",cbScheme_redir);
 593 }
 594 function unregisterHandler(){
 595   protocol.unhandle("http",cbScheme_redir);
 596   protocol.unhandle("https",cbScheme_redir);
 597   protocol.unhandle("ws",cbScheme_redir);
 598   protocol.unhandle("wss",cbScheme_redir);
 599 }
 600
 601 function forwardCookie(){
 602   const choice = dialog.showMessageBoxSync(null,  {
 603     type: 'warning',
 604     title: 'Confirm cookie forwarding with global redirection',
 605     message: 'Cookies are used to access your account. Forwarding cookies is vulnerable to global redirection server, proceed to enable cookie forwarding with global redirection?',
 606     buttons: ['No','Yes']
 607   })
 608   if(1===choice) bForwardCookie=true;
 609 }
 610 function msgbox_info(msg){
 611   dialog.showMessageBoxSync(null,  {
 612     type: 'info',
 613     title: msg,
 614     message: msg,
 615     buttons: ['OK']
 616   })
 617 }
 618
 619 async function updateApp(url){//url must ending with "/"
 620   let msg;
 621   do {
 622     try {
 623       let res = await fetch(url+"package.json");
 624       let packageS = await res.text();
 625       {//the last part of version string is the version number, must keep increasing
 626         let head = packageS.slice(2,40);
 627         let iV = head.indexOf("version");
 628         if(iV<0) {
 629           msg = "remote package.json corrupted"
 630           break;
 631         }
 632         iV = iV + 10;
 633         let iE = head.indexOf('"',iV+4);
 634         let iS = head.lastIndexOf('.',iE-1);
 635         let nLatestVer = parseInt(head.substring(iS+1,iE));
 636
 637         let ver = app.getVersion();
 638         iS = ver.lastIndexOf('.');
 639         let nVer = parseInt(ver.substring(iS+1));
 640         if(nVer>=nLatestVer){
 641           msg = `Current version ${ver} is already up to date`;
 642           break;
 643         }
 644         const choice = dialog.showMessageBoxSync(null,  {
 645           type: 'warning',
 646           title: `Update from ${url}`,
 647           message: `Proceed to update from ${ver} to ${head.substring(iV,iE)}?`,
 648           buttons: ['YES','NO']
 649         });
 650         if(1===choice) return;
 651       }
 652
 653       writeFile("package.json", packageS);
 654
 655       fetch2file(url,"webview.js");
 656       fetch2file(url,"index.html");
 657       msg = "Update completed";
 658     }catch(e){
 659       msg = "Fail to update"
 660     }
 661   }while(false);
 662   dialog.showMessageBoxSync(null,  {
 663     type: 'info',
 664     title: `Update from ${url}`,
 665     message: msg,
 666     buttons: ['OK']
 667   })
 668 }
 669
 670 async function fetch2file(urlFolder, filename, bOverwritten=true){
 671   let pathname=path.join(__dirname,filename);
 672   if(!bOverwritten && fs.existsSync(pathname)) return;
 673   let res = await fetch(urlFolder+filename);
 674   let str =  await res.text();
 675   writeFile(pathname, str);
 676 }
 677
 678 async function writeFile(filename, str){
 679   let pathname=filename+".new";
 680   fs.writeFile(pathname, str, (err) => {
 681     if(err) throw "Fail to write";
 682     fs.rename(pathname,filename,(e1)=>{
 683       if(e1) throw "Fail to rename";
 684     });
 685   });
 686 }
 687
 688 function help(){
 689   const readme = "README.md";
 690   const htmlFN = path.join(__dirname,readme);
 691   let js=`{let t=tabs.children[iTab];t.dataset.jsonce=BML_md;t.src="file://${htmlFN}"}`;
 692   win.webContents.executeJavaScript(js,false)
 693 }
 694
 695 async function initTranslateRes(lang){
 696   let basename=path.join(__dirname,"translate.");
 697   let fname = basename+lang;
 698   if(!fs.existsSync(fname))
 699     fname = basename+lang.slice(0,2);
 700   try {
 701     let json = await fs.promises.readFile(fname,'utf8');
 702     translateRes = JSON.parse(json);
 703   } catch (e){}
 704   topMenu();
 705 }
 706
 707 function translate(str){
 708   let result;
 709   if(translateRes && (result=translateRes[str])) return result;
 710   return str;
 711 }