path: root/oide2java.html

<!DOCTYPE html>
<html>
<head>
  <title>Convert online-ide projects to java</title>
  <meta charset="utf8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="author" content="Florian Fischer">

  <style>
    :root {
      /* define applied colors */
      --bg: #fdfdfd;
      --fg: #1a1a1a;
      --link-color: #0000EE;
    }
    @media (prefers-color-scheme: dark) {
      /* change apllied colors to the dark gruvbox pallet
       * https://github.com/morhetz/gruvbox
       */
      :root {
        --bg: #282828; /* dark bg */
        --fg: #ebdbb2; /* dark fg */
	--link-color: #d79921; /* yellow */
      }
    }
    
    html {
      line-height: 1.5;
      font-family: Georgia, serif;
      font-size: 20px;
      color: var(--fg);
      background-color: var(--bg);
    }
    
    body {
      margin: 0 auto;
      max-width: 36em;
      padding-left: 50px;
      padding-right: 50px;
      padding-top: 50px;
      padding-bottom: 50px;
      hyphens: auto;
      word-wrap: break-word;
      text-rendering: optimizeLegibility;
      font-kerning: normal;
    }

    footer {
      position:absolute;
      bottom: 0;
    }

    a {
      color: var(--link-color);
    }

    a:visited {
      color: var(--link-color);
    }
    
    @media (max-width: 600px) {
      body {
        font-size: 0.9em;
        padding: 1em;
      }
    }
  </style>

  <script language="javascript" type="text/javascript">
   /* Zip class put into public domain by Spiderpoison
      https://stackoverflow.com/questions/8608724/how-to-zip-files-using-javascript
   */
  class Zip {

      constructor(name) {
          this.name = name;
          this.zip = new Array();
          this.file = new Array();
      }
      
      dec2bin=(dec,size)=>dec.toString(2).padStart(size,'0');
      str2dec=str=>Array.from(new TextEncoder().encode(str));
      str2hex=str=>[...new TextEncoder().encode(str)].map(x=>x.toString(16).padStart(2,'0'));
      hex2buf=hex=>new Uint8Array(hex.split(' ').map(x=>parseInt(x,16)));
      bin2hex=bin=>(parseInt(bin.slice(8),2).toString(16).padStart(2,'0')+' '+parseInt(bin.slice(0,8),2).toString(16).padStart(2,'0'));
      
      reverse=hex=>{
          let hexArray=new Array();
          for(let i=0;i<hex.length;i=i+2)hexArray[i]=hex[i]+''+hex[i+1];
          return hexArray.filter((a)=>a).reverse().join(' '); 
      }
      
      crc32=r=>{
          for(var a,o=[],c=0;c<256;c++){
              a=c;
              for(var f=0;f<8;f++)a=1&a?3988292384^a>>>1:a>>>1;
              o[c]=a;
          }
          for(var n=-1,t=0;t<r.length;t++)n=n>>>8^o[255&(n^r[t])];
          return this.reverse(((-1^n)>>>0).toString(16).padStart(8,'0'));
      }
      
      fecth2zip(filesArray,folder=''){
          filesArray.forEach(fileUrl=>{
              let resp;               
              fetch(fileUrl).then(response=>{
                  resp=response;
                  return response.arrayBuffer();
              }).then(blob=>{
                  new Response(blob).arrayBuffer().then(buffer=>{
                      console.log(`File: ${fileUrl} load`);
                      let uint=[...new Uint8Array(buffer)];
                      uint.modTime=resp.headers.get('Last-Modified');
                      uint.fileUrl=`${this.name}/${folder}${fileUrl}`;                            
                      this.zip[fileUrl]=uint;
                  });
              });             
          });
      }
      
      str2zip(name,str,folder){
          let uint=[...new Uint8Array(this.str2dec(str))];
          uint.name=name;
          uint.modTime=new Date();
          uint.fileUrl=`${this.name}/${folder}${name}`;
          this.zip[uint.fileUrl]=uint;
      }
      
      files2zip(files,folder){
          for(let i=0;i<files.length;i++){
              files[i].arrayBuffer().then(data=>{
                  let uint=[...new Uint8Array(data)];
                  uint.name=files[i].name;
                  uint.modTime=files[i].lastModifiedDate;
                  uint.fileUrl=`${this.name}/${folder}${files[i].name}`;
                  this.zip[uint.fileUrl]=uint;                            
              });
          }
      }
      
      makeZip(){
          let count=0;
          let fileHeader='';
          let centralDirectoryFileHeader='';
          let directoryInit=0;
          let offSetLocalHeader='00 00 00 00';
          let zip=this.zip;
          for(const name in zip){
              let modTime=(()=>{
                  const lastMod=new Date(zip[name].modTime);
                  const hour=this.dec2bin(lastMod.getHours(),5);
                  const minutes=this.dec2bin(lastMod.getMinutes(),6);
                  const seconds=this.dec2bin(Math.round(lastMod.getSeconds()/2),5);
                  const year=this.dec2bin(lastMod.getFullYear()-1980,7);
                  const month=this.dec2bin(lastMod.getMonth()+1,4);
                  const day=this.dec2bin(lastMod.getDate(),5);                        
                  return this.bin2hex(`${hour}${minutes}${seconds}`)+' '+this.bin2hex(`${year}${month}${day}`);
              })();                   
              let crc=this.crc32(zip[name]);
              let size=this.reverse(parseInt(zip[name].length).toString(16).padStart(8,'0'));
              let nameFile=this.str2hex(zip[name].fileUrl).join(' ');
              let nameSize=this.reverse(zip[name].fileUrl.length.toString(16).padStart(4,'0'));
              let fileHeader=`50 4B 03 04 14 00 00 00 00 00 ${modTime} ${crc} ${size} ${size} ${nameSize} 00 00 ${nameFile}`;
              let fileHeaderBuffer=this.hex2buf(fileHeader);
              directoryInit=directoryInit+fileHeaderBuffer.length+zip[name].length;
              centralDirectoryFileHeader=`${centralDirectoryFileHeader}50 4B 01 02 14 00 14 00 00 00 00 00 ${modTime} ${crc} ${size} ${size} ${nameSize} 00 00 00 00 00 00 01 00 20 00 00 00 ${offSetLocalHeader} ${nameFile} `;
              offSetLocalHeader=this.reverse(directoryInit.toString(16).padStart(8,'0'));
              this.file.push(fileHeaderBuffer,new Uint8Array(zip[name]));
              count++;
          }
          centralDirectoryFileHeader=centralDirectoryFileHeader.trim();
          let entries=this.reverse(count.toString(16).padStart(4,'0'));
          let dirSize=this.reverse(centralDirectoryFileHeader.split(' ').length.toString(16).padStart(8,'0'));
          let dirInit=this.reverse(directoryInit.toString(16).padStart(8,'0'));
          let centralDirectory=`50 4b 05 06 00 00 00 00 ${entries} ${entries} ${dirSize} ${dirInit} 00 00`;
          this.file.push(this.hex2buf(centralDirectoryFileHeader),this.hex2buf(centralDirectory));                
          let a = document.createElement('a');
          a.href = URL.createObjectURL(new Blob([...this.file],{type:'application/octet-stream'}));
          a.download = `${this.name}.zip`;
          a.click();              
      }
  }
  </script>

  <script language="javascript" type="text/javascript">
    /*
    @licstart  The following is the entire license notice for the
    JavaScript code in this page.

    Copyright (C) 2025 Florian Fischer

    The JavaScript code in this page is free software: you can
    redistribute it and/or modify it under the terms of the GNU
    General Public License (GNU GPL) as published by the Free Software
    Foundation, either version 3 of the License, or any later version.
    The code is distributed WITHOUT ANY WARRANTY;
    without even the implied warranty of MERCHANTABILITY or FITNESS
    FOR A PARTICULAR PURPOSE.  See the GNU GPL for more details.

    As additional permission under GNU GPL version 3 section 7, you
    may distribute non-source (e.g., minimized or compacted) forms of
    that code without the copy of the GNU GPL normally required by
    section 4, provided you include this license notice and a URL
    through which recipients can access the Corresponding Source.

    @licend  The above is the entire license notice
    for the JavaScript code in this page.
    */

  function convertCode(oideCode) {
    // TODO: Use a better regex
    // let printlnRegex = /^(\s*)(println)/g
    let printlnRegex = /println/g
    javaCode = oideCode.replace(printlnRegex, "System.out.println");

    // TODO: Warn about long

    // TODO: Implement Online-IDE convenience conversion

    // TODO: move code outside of a class into a main method
    return javaCode;
  }

  function oide2java(workspace) {
    let z = new Zip(workspace.name);
    for (let module of workspace.modules) {
      let moduleCode = convertCode(module.text);
      z.str2zip(module.name + ".java", moduleCode, "");
    }
    z.makeZip();
  }

  function convertWorkspaceFile() {
    let workspaceFile = document.getElementById("json").files[0];
    let reader = new FileReader();
    reader.readAsText(workspaceFile);

    reader.onload = function() {
      oide2java(JSON.parse(reader.result));
    };
  }
  </script>
</head>

<body>
<h2>Convert an Online-IDE workspace to java code</h2>
<p><i>The conversation is done by your browser and no data is transfered to or otherwise processed by a third party.</i></p>
<div>
<form>
  Online-IDE workspace:
  <input id="json" type="file" />
  <input id="convert_button" value="convert" type="button" onclick="convertWorkspaceFile();" />
  </code>
</form>
</div>
<footer>
<p xmlns:cc="http://creativecommons.org/ns#">Diese Seite von <span property="cc:attributionName">Florian Fischer</span> ist unter folgender Lizenz veröffentlicht: <a href="https://creativecommons.org/licenses/by-sa/4.0/?ref=chooser-v1" target="_blank" rel="license noopener noreferrer" style="display:inline-block;">CC BY-SA 4.0<img style="height:22px!important;margin-left:3px;vertical-align:text-bottom;" src="https://mirrors.creativecommons.org/presskit/icons/cc.svg?ref=chooser-v1" alt=""><img style="height:22px!important;margin-left:3px;vertical-align:text-bottom;" src="https://mirrors.creativecommons.org/presskit/icons/by.svg?ref=chooser-v1" alt=""><img style="height:22px!important;margin-left:3px;vertical-align:text-bottom;" src="https://mirrors.creativecommons.org/presskit/icons/sa.svg?ref=chooser-v1" alt=""></a></p>
</footer>

</body>
</html>