cowsh.js

// Coco compiler wrapper for WSH
// (must be placed in the same directory as coco.js)
// Usage: cscript cowsh.js [--watch] file
// inspired by http://kennyj-jp.blogspot.com/2011/01/coffeescriptwindows.html

var fs = WScript.CreateObject("Scripting.FileSystemObject");
var scriptPath = WScript.ScriptFullName.slice(
                      0, -WScript.ScriptName.length);
var Coco = new new Function(
  fs.OpenTextFile(scriptPath + "coco.js", 1).ReadAll()
)().Coco;

function compileFile(file) {
  var fh = fs.OpenTextFile(file, 1);
  var src = fh.ReadAll();
  fh.Close();

  var output = file.replace(/\.co$/i, '') + '.js';
  WScript.Echo('Compiling ' + file + ' to ' + output);

  try {
    var compiled = Coco.compile(src);
  } catch(e) {
    WScript.Echo(e.message);
    return;
  }

  var fh = fs.OpenTextFile(output, 2, true);
  fh.Write(compiled);
  fh.Close();
}

function watchFile(file) {
  var sh = new ActiveXObject("WScript.Shell");
  var fullPath = getFullPath(file, sh.CurrentDirectory);
  var drive = getDrive(fullPath);

  var basename = fullPath.replace(/^.*\\/, '');
  var dir = fullPath.slice(2).slice(0, -basename.length);

  var computer = '.';
  var wmi = GetObject("winmgmts:\\\\" + computer + "\\root\\CIMV2");

  WScript.Echo('Watching ' + drive + dir + ' for file ' + basename);

  var wql = [
    "SELECT * FROM __InstanceModificationEvent WITHIN 2 WHERE ",
    "Targetinstance ISA 'CIM_DataFile' AND ",
    "TargetInstance.Drive = '" + drive + "' AND ",
    "TargetInstance.Path = '" + dir.split('\\').join('\\\\') + "'"
    ].join('');

  var eventSrc = wmi.ExecNotificationQuery(wql);

  while (true) {
    var eventObj = eventSrc.NextEvent();
    var objItem = eventObj.TargetInstance;

    if (objItem.Name === fullPath.toLowerCase()) {
      compileFile(file);
    }
  }
}

function getFullPath(file, base) {
  if (file.indexOf('\\') === 0) {
    file = getDrive(base) + file;
  } else if (!getDrive(file)) {
    file = base + '\\' + file;
  }
  return file
  .replace(/\\(\.)?\\/g, '\\') // replace \.\ and \\ to \
  .replace(/\\[^\\]*\\\.\.\\/g, '\\') // replace \foo\..\ to \
  .replace(/:\\(..\\)*/, ':\\'); // replace :\..\ to :\
}

function getDrive(file) {
  var m;
  if (m = file.match(/^([a-zA-Z]:)/)) {
    return m[1].toUpperCase();
  }
  return null;
}

function main() {
  var usage = 'Usage: cscript cowsh.js [--watch] file';
  var scriptPath = WScript.ScriptFullName.slice(
                      0, -WScript.ScriptName.length);

  var args = WScript.Arguments;
  var len = args.length;
  if (len === 0) {
    WScript.Echo(usage);
    WScript.Quit(1);
  } else {
    var watch = false;
    var i = 0;
    if (/^-(?:w|-watch)$/.test(args.Item(i))) {
      watch = true;
      if (++i == len) {
        WScript.Echo(usage);
        WScript.Quit(1);
      }
    }
    var file = args.Item(i).replace(/\//g, '\\');

    compileFile(file);
    if (watch) {
      watchFile(file);
    }
  }
}

main();