String currentJslibPath = "";

  // create the require function so dependencies can be done in proper order

  Map<File,ScriptableObject> exports = new HashMap<File,ScriptableObject>();

  ScriptableObject global = GlobalData.getGlobalScope();

  Log log = LogFactory.getLog(ModuleLoader.class);

  Map<File, Long> lastTimeStamps = new HashMap<File, Long>();

  NativeArray pathsArray;

  NativeArray autoLoadArray;

  public ModuleLoader(){

    global.put("require", global, this);

    global.setAttributes("require", ScriptableObject.PERMANENT);

  }

  public void providePaths(Object[] paths){

    pathsArray = new NativeArray(paths);

    ScriptRuntime.setObjectProtoAndParent((ScriptableObject) pathsArray, global);

    autoLoadArray = new NativeArray(paths.length == 1 ? new Object[]{true} : new Object[]{true, true});

    ScriptRuntime.setObjectProtoAndParent((ScriptableObject) autoLoadArray, global);

    this.put("paths", this, pathsArray);

    this.setAttributes("paths", ScriptableObject.PERMANENT);

    this.put("autoLoad", this, autoLoadArray);

    this.setAttributes("autoLoad", ScriptableObject.PERMANENT);

  }

  public void scanForFiles(){

    PersistableClass.persistClass.set(false);

    for(int i = 0; i < pathsArray.getLength(); i++){

      String path = pathsArray.get(i, pathsArray).toString();

      if(Boolean.TRUE.equals(autoLoadArray.get(i, autoLoadArray))){

        for(File file : DataSourceManager.getConfigFiles(new File(path))){

          try {

            call(PersevereContextFactory.getContext(), global, global, new Object[]{file});

          } catch (RhinoException e) {

            log.error(e.details() + " on line " + e.lineNumber() + " in " + e.sourceName() + '\n'+ e.getScriptStackTrace());

          } catch (Throwable e) {

            throw new RuntimeException("Trying to load " + file.getAbsolutePath(), e);

          }

        }

      }

    }

  }

  @Override

  synchronized public Object call(Context cx, Scriptable scope, Scriptable thisObj, Object[] args) {

    Transaction previousTransaction = Transaction.currentTransaction();

    int pathsCount = (int) pathsArray.getLength();

    File jslibFile = null;

    String filename;

    String oldJsLibPath = currentJslibPath;

    ScriptableObject exportObject;

    try {

      if(args[0] instanceof File){

        jslibFile = (File) args[0];

        filename = jslibFile.getCanonicalPath();

        filename = filename.replace(File.separatorChar, '/');

        for(int i = 0; i < pathsCount; i++){

          String path = pathsArray.get(i, pathsArray).toString();

          path = new File(path).getCanonicalPath().replace(File.separatorChar, '/');

          if(path.length() > 0 && !(path.endsWith("/") || path.endsWith(File.separator)))

            path += '/';

          if(filename.indexOf(path) > -1){

            filename = filename.substring(filename.indexOf(path) + path.length());

            break;

          }

        }

      }

      else {

        filename = args[0].toString();

        if(filename.startsWith("."))

          filename = currentJslibPath + filename;

        filename = Pattern.compile("[^\\/]*\\/\\.\\.\\/").matcher(filename).replaceAll("");

        filename = filename.replace("./", "");

        for(int i = 0; i < pathsCount; i++){

          String path = pathsArray.get(i, pathsArray).toString();

          if(path.length() > 0 && !(path.endsWith("/") || path.endsWith(File.separator)))

            path += '/';

          jslibFile = new File(path + filename);

          if(jslibFile.isFile())

            break;

          if(!filename.endsWith(".js")){

            filename += ".js";

            jslibFile = new File(path + filename);

            if(jslibFile.isFile())

              break;

          }

        }

      }

      String id = filename;

      if (filename.endsWith(".js"))

        id = filename.substring(0, filename.length() - 3);

      if(jslibFile == null || !jslibFile.isFile())

        throw ScriptRuntime.constructError("Error", "File not found " + filename);

      exportObject = exports.get(jslibFile);

      Long lastTimeStamp = lastTimeStamps.get(jslibFile);

      if(lastTimeStamp == null || lastTimeStamp < jslibFile.lastModified()){

        Transaction.startTransaction();

        lastTimeStamps.put(jslibFile, jslibFile.lastModified());

        FileInputStream inStream = new FileInputStream(jslibFile);

        exportObject = new NativeObject();

        ScriptRuntime.setObjectProtoAndParent((ScriptableObject) exportObject, global);

        ScriptableObject moduleObject = new NativeObject();

        ScriptRuntime.setObjectProtoAndParent((ScriptableObject) moduleObject, global);

        moduleObject.put("id", moduleObject, id);

        // setup the module scope

        ScriptableObject moduleScope = new NativeObject();

        moduleScope.setParentScope(global);

        int lastSlash = filename.lastIndexOf('/');

        currentJslibPath = lastSlash == -1 ? "" : filename.substring(0,lastSlash + 1);

        moduleScope.put("exports", moduleScope, exportObject);

        moduleScope.put("module", moduleScope, moduleObject);

        // memoize

        exports.put(jslibFile, exportObject);

        // evaluate the script

        try {

          cx.evaluateString(moduleScope, IOUtils.toString(inStream, "UTF-8"), filename, 1, null);

        } catch (RuntimeException e) {

          // revert

          exports.remove(jslibFile);

          throw e;

        }

        // re-retrieve it in case the library changed it

        exportObject = (ScriptableObject) moduleScope.get("exports", moduleScope);

        exports.put(jslibFile, exportObject);

        if("jsgi-app.js".equals(filename)){

          // handle jackconfig.js, setting up the app if it is there

          global.put("app", global, exportObject.get("app", exportObject));

        }

        // freeze it

        //exportObject.sealObject();

        Transaction.currentTransaction().commit();

      }

    } catch (IOException e) {

      throw ScriptRuntime.constructError("Error",e.getMessage());

    }

    finally{

      currentJslibPath = oldJsLibPath;

      previousTransaction.enterTransaction();

    }

    return exportObject;

  }

  public void freezeExports(){

    throw new RuntimeException("not implemented");

    /*

    for(String filename : new HashSet<String>(jslibFiles.keySet())){

      try {

        ScriptableObject exportObject = (ScriptableObject) call(PersevereContextFactory.getContext(), global, global, new Object[]{filename});

        exportObject.sealObject();

      } catch (RhinoException e) {

        log.error(e.details() + " on line " + e.lineNumber() + " in " + e.sourceName() + '\n'+ e.getScriptStackTrace());

      }

    }

*/

  }

  public void startTimer(){

    GlobalData.jsTimer.schedule(new TimerTask(){

      @Override

      public void run() {

        try{

          scanForFiles();

        } catch (Throwable e){

          log.error(e);

        }

      }

     

    }, 1000, 500);

  }

}