Subversion Repositories SmartDukaan

/*

Copyright (c) 2009 Jordan Bach, http://www.utdallas.edu/~jrb048000/

Permission is hereby granted, free of charge, to any person obtaining a copy

of this software and associated documentation files (the "Software"), to deal

in the Software without restriction, including without limitation the rights

to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

copies of the Software, and to permit persons to whom the Software is

furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in

all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

THE SOFTWARE.

*/

/*

List Reorder	 <http://www.utdallas.edu/~jrb048000/ListReorder/>

Enables drag-and-drop reordering of list items for any simple ordered <ol> or unordered <li> list.

Author: Jordan Bach

Version: 0.1

Created: January 1, 2009

License: MIT License

Constructor

	$(expr).ListOrder(options)

Methods:

	makeDefaultOrder - sets the current list order to [0, 1, 2, ...]

	restoreOrder - returns the list to its original order

Events:

	listorderchanged - Fired after a list item is dropped. The 2nd argument

		is a jQuery object representing the list that fired the event. 

		The 3rd argument is an array where the values represent

		the original index of each list item.

Options:

	itemHoverClass : 'itemHover',

	dragTargetClass : 'dragTarget',

	dropTargetClass : 'dropTarget',

	dragHandleClass : 'dragHandle'

*/

(function($){

$.fn.ListReorder = function (options) {

	$.fn.ListReorder.defaults = {

		itemHoverClass : 'itemHover',

		dragTargetClass : 'dragTarget',

		dropTargetClass : 'dropTarget',

		dragHandleClass : 'dragHandle',

		useDefaultDragHandle : false

	};

	var opts = $.extend({}, $.fn.ListReorder.defaults, options);

	return this.each(function() {

		var theList = $(this),   // The list (<ul>|<ol>)

			theItems = $('li', theList), // All <li> elements in the list

			dragActive = false,          // Are we currently dragging an item?

			dropTarget = null,           // The list placeholder

			dragTarget = null,           // The element currently being dragged

			dropIndex = -1,           	 // The list index of the dropTarget

			offset = {},				 // Positions the mouse in the dragTarget

			listOrder = [],				 // Keeps track of order relative to original order

			ref = this;

		theList.mouseout(ul_mouseout);

		// Create the drag target

		dragTarget = $('<div></div>');

		dragTarget.insertAfter(theList);

		dragTarget.hide();

		dragTarget.css('position', 'absolute');

		dragTarget.addClass(opts.dragTargetClass);

		for (var i = 0; i < theItems.length; i++)

			listOrder.push(i);

		resetList();

		function resetList() {	

			theItems = $('li', theList),

			// For each <li> in the list

			theItems.each(function() {

				var li = $(this);

				var dragHandle = $('<span></span>');

				dragHandle.addClass(opts.dragHandleClass)

					.mouseover(li_mouseover)

					.mousedown(dragHandle_mousedown);

				if (opts.useDefaultDragHandle)

					dragHandle.css({

						'display' : 'block',

						'float' : 'right',

						'width' : '10px',

						'height' : '10px',

						'border' : '2px solid #333',

						'background' : '#ccc',

						'cursor' : 'move'

					});

				$('.' + opts.dragHandleClass, li).remove();

				li.prepend(dragHandle);

			});

			clearListItemStyles();

		}

		// Return all list items to their default state

		function clearListItemStyles() {

			theItems.each(function() {

				var li = $(this);

				li.removeClass(opts.itemHoverClass);

				li.removeClass(opts.dropTargetClass);

			});

		}

		// Handle any cleanup when the mouse leaves the list

		function ul_mouseout() {

			if (!dragActive)

				clearListItemStyles();

		}

		// Add a hover class to a list item on mouseover

		function li_mouseover() {

			if (!dragActive) {

				clearListItemStyles();

				$(this).parent().addClass(opts.itemHoverClass);

			}

		}

		// Prepare the list for dragging an item

		function dragHandle_mousedown(e) {

			var li = $(this).parent();

			dragActive = true;

			dropIndex = theItems.index(li);

			// Show the drag target

			dragTarget.html(li.html());

			dragTarget.css('display', 'block');

			offset.top = e.pageY - li.offset().top;

			offset.left = e.pageX - li.offset().left;

			updateDragTargetPos(e);

			// Insert the placeholder

			dropTarget = li;

			dropTarget.html('');

			dropTarget.css('height', dragTarget.css('height'));

			dragTarget.css('width', dropTarget.width() + 'px');

			dropTarget.addClass(opts.dropTargetClass);

			// Disable Text and DOM selection

			$(document).disableTextSelect();

			$(document).mouseup(dragHandle_mouseup);

			$(document).mousemove(document_mousemove);	

		}

		// If this were on the element, we could lose the drag on the element 

		// if we move the mouse too fast

		function document_mousemove(e) {

			if (dragActive) {

				// drag target follows mouse cursor

				updateDragTargetPos(e);

				// Don't do mess with drop index if we are above or below the list

				if (y_mid(dragTarget) > y_bot(theList) 

					|| y_mid(dragTarget) < y_top(theList)) {

					return;

				}

				// detect position of drag target relative to list items

				// and swap drop target and neighboring item if necessary

				if (y_mid(dragTarget) + 5 < y_top(dropTarget)) {

					swapListItems(dropIndex, --dropIndex);

				} else if (y_mid(dragTarget) - 5 > y_bot(dropTarget)) {

					swapListItems(dropIndex, ++dropIndex);

				}

			}

		}

		function dragHandle_mouseup() {

			// Restore the drop target

			dropTarget.html(dragTarget.html());

			dropTarget.removeClass(opts.dragTargetClass);

			dropTarget = null;

			// Hide the drag target

			dragTarget.css('display', 'none');

			dragActive = false;

			dragTarget.unbind('mouseup', dragHandle_mouseup);

			$(document).unbind('mousemove', document_mousemove);

			resetList();

			theList.trigger('listorderchanged', [theList, listOrder]);

			// Re-enable text selection

			$(document).enableTextSelect();

			$(document).unbind('mouseup', dragHandle_mouseup);

		}

		function updateDragTargetPos(e) {

			dragTarget.css({ 

				'top' : e.pageY - offset.top + 'px',

				'left' : e.pageX - offset.left + 'px'

			});

		}

		// Change the order of two list items

		function swapListItems(oldDropIndex, newDropIndex) {

			// keep indices in bounds

			if (dropIndex < 0) {

				dropIndex = 0;

				return;

			} else if (dropIndex >= theItems.length) {

				dropIndex = theItems.length - 1;

				return;

			}

			var t = listOrder[oldDropIndex];

			listOrder[oldDropIndex] = listOrder[newDropIndex];

			listOrder[newDropIndex] = t;

			// swap list items

			var oldDropTarget = theItems.get(oldDropIndex),

				newDropTarget = theItems.get(newDropIndex),

				temp1 = $(oldDropTarget).clone(true);

				temp2 = $(newDropTarget).clone(true);

			$(oldDropTarget).replaceWith(temp2)

				.mouseover(li_mouseover)

				.mousedown(dragHandle_mousedown);

			$(newDropTarget).replaceWith(temp1)

				.mouseover(li_mouseover)

				.mousedown(dragHandle_mousedown);

			// reset so it is valid on next use

			theItems = $('li', theList);

			dropTarget = $(theItems.get(newDropIndex));

		}

		function y_top(jq) {

			return jq.offset().top;

		}

		function y_mid(jq) {

			return (y_top(jq) + y_bot(jq)) / 2

		}

		function y_bot(jq) {

			return jq.offset().top + jq.outerHeight();

		}

		this.makeDefaultOrder = function() {

			for (var i = 0; i < listOrder.length; i++)

				listOrder[i] = i;

		}

		this.restoreOrder = function() { 

			for (var i = 0; i < theItems.length; i++) {

				if (i != listOrder[i]) {

					var k = 0;

					for (; k < listOrder.length; k++)

						if (listOrder[k] == i)

							break;

					swapListItems(i, k);

				}

			}

			theList.trigger('listorderchanged', [theList, listOrder]);

		}

	});

}

})(jQuery);