Bridge talk for InDesign CS4/CS5 js

From time to time I have to write quite complex scripts using BridgeTalk. Long ago I new that it's possible to pass complex objects -- arrays, DOM and custom objects -- via BridgeTalk, but only recently I applied this in practice. Below is an example: a new version of the code from a previous post.

#target indesign

var file = new File('~/Desktop/toysForUs.pdf');

if (!file.exists) exit();

var customObject = {}
customObject.file = file;
customObject.cropPage = 'CropToType.MEDIABOX';
customObject.resolution = 300;
customObject.usePageNumber = true;
customObject.regExp = '\\.pdf$';
var serializedObject = customObject.toSource();

CreateBridgeTalkMessage(serializedObject);

function CreateBridgeTalkMessage(serializedObject) {
     var bt = new BridgeTalk();
     bt.target = "photoshop";
     var script = "ResaveInPS = " + ResaveInPS.toSource() + "\r";
     script += "ResaveInPS(" + serializedObject + ");";
     bt.body = script;

     bt.onError = function(errObj) {
          $.writeln("Error: " + errObj.body);
     }

     bt.send(100);
}

function ResaveInPS(serializedObject) {
     var reconstructedObject = eval(serializedObject);
     var regExp = new RegExp(reconstructedObject.regExp.replace(decodeURI("%5C%5C"), decodeURI("%5C")));
     
      if (reconstructedObject.file.name.match(regExp) != null) {
          $.writeln( "This is PDF" );
          var pdfOpenOptions = new PDFOpenOptions;
          pdfOpenOptions.cropPage = eval(reconstructedObject.cropPage);
          pdfOpenOptions.resolution = reconstructedObject.resolution;
          pdfOpenOptions.usePageNumber = eval(reconstructedObject.usePageNumber);
     }
     else {
          $.writeln( "This is not PDF" );
     }
               
     app.displayDialogs = DialogModes.NO;
     var doc = app.open(reconstructedObject.file, pdfOpenOptions);
     app.displayDialogs = DialogModes.ALL;
}

This approach, in my opinion, has at least two advantages:

• You can pass all parameters in a single custom object instead of using a dozens of arguments
• You can pass DOM objects like files and folders directly. So this way you can avoid making some extra steps: e.g. get an image's file path in InDesign, pass it to Photoshop, then in Photoshop create the File object from this path.

It is important to note that in the function to be send via BridgeTalk we should use eval() for enumerations, boolean values and may be some other stuff.