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/**
 *
 * Duplicate Me!
 * Copyright: (c)2016. Vladimir Gaintsev, gaintsev@gmail.com. All rights reserved.
 *
 */

/*=============================================
=            Check Active Document            =
=============================================*/
function checkActiveDocument() {
  if (!documents.length) {
    alert('No active documents. First open or create a document.');
    return false;
  }
  return true;
}

/*========================================
=            Check Layer Type            =
========================================*/
function checkLayerSet(layerSet) {
  if (layerSet.typename == 'LayerSet') {
    return true;
  }
  alert('First select a group layer.');
  return false;
}

/*======================================
=            Get Layer Size            =
======================================*/
function getLayerSize(layer) {
  var bounds = layer.bounds;
  var width = bounds[2] - bounds[0];
  var height = bounds[3] - bounds[1];
  var size = [width, height];
  return size;
}

/*===================================
=            Main script            =
===================================*/

if (checkActiveDocument()) {

  // Define variables
  var activeDocument = app.activeDocument;
  var activeLayer = activeDocument.activeLayer;
  var activeLayerSizes = getLayerSize(activeLayer);

  // Default parameters
  var itemAlign        = ['inline', 'column', 'grid'];
  var itemCount        = 6;
  var itemCountInRow   = 3;
  var itemMarginRight  = 1;
  var itemMarginBottom = 1;


  if (checkLayerSet(activeLayer)) {

    // Building dialog window
    var win = new Window('dialog','Duplicate Me!');
    win.alignChildren = 'center';

    var ddlPanel = win.add('panel', undefined, 'Diplicates align style');
    var ddlItemAlign = ddlPanel.add('dropdownlist', undefined, itemAlign);
    ddlItemAlign.selection = 0;

    var panelItemCount = win.add('panel', undefined, 'Duplicates Count');
    var etItemCount = panelItemCount.add('edittext', undefined, itemCount);

    var panelItemCountInRow = win.add('panel', undefined, 'Duplicates in row (only for grid style)');
    var etItemCountInRow = panelItemCountInRow.add('edittext', undefined, itemCountInRow);

    var panelMargins = win.add('panel', undefined, 'Margins');
    panelMargins.orientation = 'row';
    panelMargins.add('statictext', undefined, 'Right margin');
    var etItemMarginRight = panelMargins.add('edittext', undefined, itemMarginRight);
    panelMargins.add('statictext', undefined, 'Bottom margin');
    var etItemMarginBottom = panelMargins.add('edittext', undefined, itemMarginBottom);

    var buttonsGroup = win.add('panel');
    buttonsGroup.orientation = 'row';
    var cancelButton = buttonsGroup.add('button', undefined, 'Cancel');
    var applyButton = buttonsGroup.add('button', undefined, 'Apply');

    cancelButton.onClick = function() {
      return win.close();
    };

    // Main script
    applyButton.onClick = function() {
      var i = 0;
      while (i < etItemCount.text) {
        activeLayer.duplicate();
        switch (ddlItemAlign.selection.text) {
          case 'inline':
            activeLayer.translate(activeLayerSizes[0] + (etItemMarginRight.text * 1), 0);
            break;
          case 'column':
            activeLayer.translate(0, activeLayerSizes[1] + (etItemMarginBottom.text * 1));
            break;
          case 'grid':
            var row = 1;
            var counter = i + 1;
            if (counter % etItemCountInRow.text == 0) {
              activeLayer.translate(-(etItemCountInRow.text * activeLayerSizes[0] + (etItemMarginRight.text * 1) * etItemCountInRow.text), activeLayerSizes[1] * row++ + (etItemMarginBottom.text * 1));
            }
            activeLayer.translate(activeLayerSizes[0] + (etItemMarginRight.text * 1), 0);
        }
        i++;
      }
      activeLayer.visible = false;
      activeLayer.allLocked = true;
      win.close();
    };
    win.show();
  }

}