JavaScripting InDesign

OK, I've confirmed my suspicion that the current version of the script hits a run-time error if a locked layer holds a pasteboard item. I'm inclined to take the easy way out here and simply exclude any such layers from this game. If the user wants to add it back in, all he need do is unlock the layer and run the script again.

So, now let's get down to the hard part: how to prevent items from colliding with pages?

I think I'm going to assume that only left/right collisions are possible. I don't know enough about the dtptools plug-in that allows different sized pages, but since I don't own it and I'm writing this script as much for me as anyone else (so few people having taken any interest), I might as well not worry about things that aren't going to affect me.

So, for any item, I have three rectangles to worry about:

1. The geometric bounds of the item
2. The bounds of the source spread
3. The bounds of the target spread

The only items I have to worry about are those that are wholly to the left or right of the source spread. I want them to appear the same distance to the left or right of the target spread. Notice that any item on the pasteboard above or below the pages that is not wholly to the left or right will not slide when moved to the target. Being where they are, they can't possibly collide with a page.

Of course, getting the bounds of a spread is non-trivial unless you're using Spread as the ruler origin for your document, so I'm going to have to switch to spread at the start and switch back afterwards. Hmm, that means we'd better reset the zero point too and restore it. That means that for an item to be wholly left, it's right-bounds value must be negative because the spread left bound will always be zero; still, it's probably safer to compare just in case.

Oh wait a cotton-picking minute! Because of the way that the spread-based coordinates work, the left side looks after itself. The coordinates are such that an item to the left of the spread will always be the same distance to the left. It's only the right side we have to worry about. Which means that all I have to worry about is the difference in width between the two spreads. So, perhaps I shouldn't even worry about whether or not an item is wholly right, just if it is right of the zero-X I should move it by the difference in widths.

Well, what do you know? It seems to work!

//DESCRIPTION: Moves all Pasteboard Items to Pasteboard of Current Spread

if (app.documents.length == 0) { exit() }
movePBitems(app.documents[0]);

function movePBitems(myDoc) {
  if (app.activeWindow.constructor.name == "StoryWindow") { return }
  var uO = myDoc.viewPreferences.rulerOrigin;
  var uZP = myDoc.zeroPoint;
  myDoc.viewPreferences.rulerOrigin = RulerOrigin.spreadOrigin;
  myDoc.zeroPoint = [0,0];
  myObjs = myDoc.pageItems.everyItem().parent;
  var moveables = new Array();
  for (var j = myObjs.length - 1; j >= 0; j--) {
    if (myObjs[j].constructor.name == "Page") { continue }
    moveables.push(myDoc.pageItems[j].id);
  }
  var mySpread = app.activeWindow.activeSpread;
  var targSpreadWidth = getSpreadWidth(mySpread);
  for (var j = moveables.length - 1; j >= 0; j--) {
    var myObj = myDoc.pageItems.itemByID(moveables[j]);
    var sourceSpread = myObj.parent;
    if (sourceSpread == mySpread) { continue }
    var sourceWidth = getSpreadWidth(sourceSpread);
    var Shift = 0;
    if (myObj.geometricBounds[3] > 0) {
      Shift = targSpreadWidth - sourceWidth;
    }
    var myBounds = myObj.geometricBounds;
    if (myObj.locked) { continue }
    try {
      myObj.move(mySpread);
    } catch(e) { continue } // myObj must be on locked layer
    myObj.move([myBounds[1] + Shift, myBounds[0]]);
  }
  myDoc.viewPreferences.rulerOrigin = uO;
  myDoc.zeroPoint = uZP;
  
  function getSpreadWidth(spread) {
    var my1stBounds = spread.pages[0].bounds;
    var myLastBounds = spread.pages[-1].bounds;
    return myLastBounds[3] - my1stBounds[1];
  }
} // end function movePBitems