Run a function on each selected frame in turn

Hi all,

I've made a script that places a text caption to either the side of a graphic frame or below it. At the moment, it only works with a single, selected graphic frame (must have an image inside it to capture the metadata). But I've hit a brick wall trying to get the script to loop when more than one frame is selected.

Here's the script before I started trying to loop it:

var doc = app.activeDocument;
var myPage = app.activeWindow.activePage;
var mySelection = app.selection[0];
var savedUnits = app.scriptPreferences.measurementUnit;
var filename = mySelection.graphics[0].itemLink.name;
var textFrameHeight = 10;
var textFrame = myPage.textFrames.add();
var captionText = filename.replace(/(.*)(\..*)/i, "$1");
var b = mySelection.geometricBounds;
var frameWidth = b[3]-b[1];
var frameHeight = b[2]-b[0];
var objectStyle = doc.objectStyles.itemByName("Photo Caption align base");

//THE DIALOG
var myList = ["Below", "Side"];
var myDialog = app.dialogs.add({name:"Credit/Caption", canCancel:true});
with (myDialog )
    with (dialogColumns.add())
        with(borderPanels.add())
            {
            staticTexts.add ({staticLabel:"Select:"});
            var myDropSelection = dropdowns.add({stringList:myList, selectedIndex:1});
            }
            
if(myDialog.show() == true){
	
	if(myDropSelection.selectedIndex == 0){
		baseCaption();
	}
	else if(myDropSelection.selectedIndex == 1){
		sideCaption();
  }
	myDialog.destroy();  
}



function baseCaption(){
// add a text frame for the caption below the graphic
textFrame.geometricBounds = [b[2], b[1], b[2] + textFrameHeight, b[3]];

//add caption text
textFrame.contents = captionText;

try {
	if(objectStyle.isValid)
		textFrame.applyObjectStyle(objectStyle);

    } catch (error) {
                /* object style not found in document */
    }
}

function sideCaption(){

// add a text frame to the right-hand side of the graphic
//[y1, x1, y2, x2] - coordinates of the top-left and bottom-right corners
//[0,  1,  2,  3] - array positions for coordinates
textFrame.geometricBounds = 
[b[2] ,b[1] + frameWidth, b[2] + textFrameHeight, b[3] + frameHeight];

textFrame.properties = {
  rotationAngle : 90
};

//fill it with the caption text
textFrame.contents = captionText;

try {
	if(objectStyle.isValid)
		textFrame.applyObjectStyle(objectStyle);

    } catch (error) {
                /* object style not found in document */
    }
  }

If some kind soul can offer any advice, that would be great.

Many thanks, J