TestHelpers.draggable = {
	// TODO: remove the unreliable offset hacks
	unreliableOffset: $.ui.ie && ( !document.documentMode || document.documentMode < 8 ) ? 2 : 0,
	// Support: Opera 12.10, Safari 5.1, jQuery <1.8
	unreliableContains: (function(){
		var element = $( "<div>" );
		return $.contains( element[ 0 ].ownerDocument, element[ 0 ] );
	})(),
	testDrag: function( el, handle, dx, dy, expectedDX, expectedDY, msg ) {
		var offsetAfter, actual, expected,
			offsetBefore = el.offset();

		$( handle ).simulate( "drag", {
			dx: dx,
			dy: dy
		});
		offsetAfter = el.offset();

		actual = { left: offsetAfter.left, top: offsetAfter.top };
		expected = { left: offsetBefore.left + expectedDX, top: offsetBefore.top + expectedDY };

		msg = msg ? msg + "." : "";
		deepEqual( actual, expected, "dragged[" + dx + ", " + dy + "] " + msg );
	},
	shouldMove: function( el, why ) {
		TestHelpers.draggable.testDrag( el, el, 50, 50, 50, 50, why );
	},
	shouldNotMove: function( el, why ) {
		TestHelpers.draggable.testDrag( el, el, 50, 50, 0, 0, why );
	},
	testScroll: function( el, position ) {
		var oldPosition = $( "#main" ).css( "position" );
		$( "#main" ).css( "position", position);
		TestHelpers.draggable.shouldMove( el, position + " parent" );
		$( "#main" ).css( "position", oldPosition );
	},
	restoreScroll: function( what ) {
		if( what ) {
			$( document ).scrollTop( 0 ).scrollLeft( 0 );
		} else {
			$( "#main" ).scrollTop( 0 ).scrollLeft( 0 );
		}
	},
	setScroll: function( what ) {
		if( what ) {
			// TODO: currently, the draggable interaction doesn't properly account for scrolled pages,
			// uncomment the line below to make the tests fail that should when the page is scrolled
			// $( document ).scrollTop( 100 ).scrollLeft( 100 );
		} else {
			$( "#main" ).scrollTop( 100 ).scrollLeft( 100 );
		}
	},
	border: function( el, side ) {
		return parseInt( el.css( "border-" + side + "-width" ), 10 ) || 0;
	},
	margin: function( el, side ) {
		return parseInt( el.css( "margin-" + side ), 10 ) || 0;
	},
	move: function( el, x, y ) {
		$( el ).simulate( "drag", {
			dx: x,
			dy: y
		});
	},
	trackMouseCss : function( el ) {
		el.bind( "drag", function() {
			el.data( "last_dragged_cursor", $( "body" ).css( "cursor" ) );
		});
	},
	trackAppendedParent : function( el ) {
		// TODO: appendTo is currently ignored if helper is original (see #7044)
		el.draggable( "option", "helper", "clone" );

		// Get what parent is at time of drag
		el.bind( "drag", function(e,ui) {
			el.data( "last_dragged_parent", ui.helper.parent()[ 0 ] );
		});
	}
};
