var currentApp = Application.currentApplication();
currentApp.includeStandardAdditions = true;
var finder = Application("Finder");
var systemEvents = Application("System Events");

// Ask a folder to process

var sourcePath = currentApp.chooseFolder ({
    withPrompt: "Choose the source folder"
}).toString();
var sourceFolder = systemEvents.aliases.byName(sourcePath);

// Create the destination folder

var container = sourceFolder.container();
var containerPath = container.path();
var destinationFolder = finder.make({
  new: "folder", at: containerPath,
  withProperties: { name: sourceFolder.name() + " - Edited" }
});

// Create an array of items to be processed

var items = systemEvents.aliases.byName(sourcePath).diskItems;
var selectedItems = [];

for (var i = 0; i < items.length; i++) {
  var item = items[i];
  if (item.class() != "folder" && item.visible()) {
    selectedItems.push(item.name());
  }
}

// Process every item

var createdFolders = [];
selectedItems.forEach(function(itemName) {
  var item = systemEvents.aliases.byName(sourcePath + "/" + itemName);
  var name = item.name().match(/(.*) - (.*)/);
  try {
    var folderName = name[1];
    if (!createdFolders.includes(folderName)) {
      var newFolder = finder.make({
        new: "folder", at: destinationFolder, withProperties: { name: folderName }
      });
      createdFolders.push(folderName);
    }
    item = finder.move(item.path(), { to: destinationFolder.folders[folderName] });
    item.name = name[2];
  } catch (error) {
    console.log("Error (item: " + item.name() + "): " + error);
  }
});