Convert AppleScript response to JSON - objective-c

Question

I have a Cocoa application, part of it takes AppleScript from the user in a web view. I currently can pass a single string from a command (e.g. the current iTunes song name), however, if I run a command that returns a record (I believe that's what it is based on my research, could be wrong) such as the below I get '(null)' as the stringValue.
tell application "iTunes"
get properties of current track
end tell
If I run this in Script Debugger I can get this as a table shown below, so it's clearly possible.
However, nothing I've tried seems to be working. Based on a number of SO answers I've tried different ways, such as looping over every descriptor index as in this question. However, this doesn't work anymore, as it seems the key is not included in the array.
So, basically, I need to be able to convert an AppleScript output to JSON. I have a serialiser so that's not the issue, as long as I can get them in to Cocoa objects I'm set. What's the best way to do this?
Thanks

Answer 1

Many months late as an answer, but in case you or anyone else cares, here is what I did with a similar problem.
Check out the (sadly defunct) AppScript framework. That combined with lightly modified SBJSON let me convert any AppleScript record into JSON via Cocoa objects.
I used it in JSON Helper which is free on the Mac AppStore. You can also see the source to an earlier version on Google code here, which might be useful if you want to use the modified version of SBJSON.
In my example below the AppleScript record is being supplied via a scripting command.
#implementation makeJSONFromRecord
- (id)performDefaultImplementation {
NSDictionary *asRecord;
NSString *result;
AEMCodecs *codecs = [[AEMCodecs alloc] init];
// Use appscript framework to unpack the event into an object we can use
asRecord =[codecs unpack:[self directParameter]];
[codecs release];
// Use the JSON framework to convert the object to JSON notation
result = [asRecord JSONRepresentation];
if (result==nil) {
//We failed to create any valid JSON so return nothing
NSLog(#"Failed to make JSON from: %#", asRecord);
result=#"";
}
// Return the result to the applescript
return result;
}
#end