SGH / COMPONENTS

  define([

  	"../core",

  	"../manipulation" // appendTo

  ], function( jQuery ) {

  
  var iframe,

  	elemdisplay = {};

  
  /**
   * Retrieve the actual display of a element
   * @param {String} name nodeName of the element
   * @param {Object} doc Document object
   */

  // Called only from within defaultDisplay
  function actualDisplay( name, doc ) {

  	var style,
  		elem = jQuery( doc.createElement( name ) ).appendTo( doc.body ),

  		// getDefaultComputedStyle might be reliably used only on attached element
  		display = window.getDefaultComputedStyle && ( style = window.getDefaultComputedStyle( elem[ 0 ] ) ) ?
  
  			// Use of this method is a temporary fix (more like optimization) until something better comes along,
  			// since it was removed from specification and supported only in FF
  			style.display : jQuery.css( elem[ 0 ], "display" );

  
  	// We don't have any data stored on the element,
  	// so use "detach" method as fast way to get rid of the element
  	elem.detach();
  
  	return display;
  }
  
  /**
   * Try to determine the default display value of an element
   * @param {String} nodeName
   */
  function defaultDisplay( nodeName ) {
  	var doc = document,
  		display = elemdisplay[ nodeName ];
  
  	if ( !display ) {
  		display = actualDisplay( nodeName, doc );
  
  		// If the simple way fails, read from inside an iframe
  		if ( display === "none" || !display ) {
  
  			// Use the already-created iframe if possible

  			iframe = (iframe || jQuery( "<iframe frameborder='0' width='0' height='0'/>" )).appendTo( doc.documentElement );

  
  			// Always write a new HTML skeleton so Webkit and Firefox don't choke on reuse
  			doc = iframe[ 0 ].contentDocument;
  
  			// Support: IE
  			doc.write();
  			doc.close();
  
  			display = actualDisplay( nodeName, doc );
  			iframe.detach();
  		}
  
  		// Store the correct default display
  		elemdisplay[ nodeName ] = display;
  	}
  
  	return display;
  }
  
  return defaultDisplay;

  
  });