/*
Copyright (c) 2009, http://seyfertdesign.com/jquery/ui-tabs-paging.html
Modified by tolstyh special for BioUML web edition.
*/

$.extend($.ui.tabs.prototype, {
	paging: function(options) {
		var opts = {
			tabsPerPage: 0,
			nextButton: '<b>&#187;</b>',
			prevButton: '<b>&#171;</b>',
			follow: false,
			cycle: false,
			selectOnAdd: false,
			followOnSelect: false
		};
		
		opts = $.extend(opts, options);

		var self = this, initialized = false, currentPage, 
			buttonWidth, containerWidth, allTabsWidth, tabWidths, 
			maxPageWidth, pages, resizeTimer = null, 
			windowHeight = $(window).height(), windowWidth = $(window).width();
		
		var idMap;//index to ID mapping
		
		function init() {
			destroy();
			
			allTabsWidth = 0, currentPage = 0, maxPageWidth = 0, buttonWidth = 0,
				pages = new Array(), tabWidths = new Array(), selectedTabWidths = new Array();
			
			containerWidth = self.element.width();
            if(self.element.children('ul').css('padding-left'))
            {
                containerWidth -= parseInt(self.element.children('ul').css('padding-left'));
            }
			
			idMap = [];
			
			// loops through LIs, get width of each tab when selected and unselected.
			var maxDiff = 0;  // the max difference between a selected and unselected tab
			self.lis.each(function(i) {			
				if (i == self.options.selected) {
					selectedTabWidths[i] = $(this).outerWidth({ margin: true });
					tabWidths[i] = self.lis.eq(i).removeClass('ui-tabs-selected').outerWidth({ margin: true });
					self.lis.eq(i).addClass('ui-tabs-selected');
					maxDiff = Math.min(maxDiff, Math.abs(selectedTabWidths[i] - tabWidths[i]));
					allTabsWidth += tabWidths[i];
				} else {
					tabWidths[i] = $(this).outerWidth({ margin: true });
					selectedTabWidths[i] = self.lis.eq(i).addClass('ui-tabs-selected').outerWidth({ margin: true });
					self.lis.eq(i).removeClass('ui-tabs-selected');
					maxDiff = Math.max(maxDiff, Math.abs(selectedTabWidths[i] - tabWidths[i]));
					allTabsWidth += tabWidths[i];
				}
				idMap[$(this).children('a').attr('href')] = i;
			});
            // fix padding issues with buttons
            // TODO determine a better way to handle this
			allTabsWidth += maxDiff + ($.browser.msie?4:0) + 9;  

			// if the width of all tables is greater than the container's width, calculate the pages
			if (allTabsWidth > containerWidth) {
				// create next button			
				li = $('<li></li>')
					.addClass('ui-state-default ui-tabs-paging-next')
					.append($('<a href="#"></a>')
							.click(function() { page('next'); return false; })
							.html(opts.nextButton));
				
				self.lis.eq(self.length()-1).after(li);
				buttonWidth = li.outerWidth({ margin: true });
				
				// create prev button
				li = $('<li></li>')
					.addClass('ui-state-default ui-tabs-paging-prev')
					.append($('<a href="#"></a>')
							.click(function() { page('prev'); return false; })
							.html(opts.prevButton));
				self.lis.eq(0).before(li);
				buttonWidth += li.outerWidth({ margin: true });
				
				// TODO determine fix for padding issues to next button
				buttonWidth += 19; 
								
				var pageIndex = 0, pageWidth = 0, maxTabPadding = 0;
				
				// start calculating pageWidths
				for (var i = 0; i < tabWidths.length; i++) {
					// if first tab of page or selected tab's padding larger than the current max, set the maxTabPadding
					if (pageWidth == 0 || selectedTabWidths[i] - tabWidths[i] > maxTabPadding)
						maxTabPadding = (selectedTabWidths[i] - tabWidths[i]);
					
					// if first tab of page, initialize pages variable for page 
					if (pages[pageIndex] == null) {
						pages[pageIndex] = { start: i };
					
					} else if ((i > 0 && (i % opts.tabsPerPage) == 0) || (tabWidths[i] + pageWidth + buttonWidth + 12) > containerWidth) {
						if ((pageWidth + maxTabPadding) > maxPageWidth)	
							maxPageWidth = (pageWidth + maxTabPadding);
						pageIndex++;
						pages[pageIndex] = { start: i };			
						pageWidth = 0;
					}
					pages[pageIndex].end = i+1;
					pageWidth += tabWidths[i];
					if (i == self.options.selected) currentPage = pageIndex;
				}
				if ((pageWidth + maxTabPadding) > maxPageWidth)	
					maxPageWidth = (pageWidth + maxTabPadding);				

			    // hide all tabs then show tabs for current page
				self.lis.hide().slice(pages[currentPage].start, pages[currentPage].end).show();
				if (currentPage == (pages.length - 1) && !opts.cycle) 
					disableButton('next');			
				if (currentPage == 0 && !opts.cycle) 
					disableButton('prev');
				
				// calculate the right padding for the next button
				buttonPadding = containerWidth - maxPageWidth - buttonWidth;
				if (buttonPadding > 0) 
					$('.ui-tabs-paging-next', self.element).css({ paddingRight: buttonPadding + 'px' });
				
				initialized = true;
			} else {
				destroy();
			}
			
			$(window).bind('resize', handleResize);
		}
		
		function page(direction) {
			currentPage = currentPage + (direction == 'prev'?-1:1);
			
			if ((direction == 'prev' && currentPage < 0 && opts.cycle) ||
				(direction == 'next' && currentPage >= pages.length && !opts.cycle))
				currentPage = pages.length - 1;
			else if ((direction == 'prev' && currentPage < 0) || 
					 (direction == 'next' && currentPage >= pages.length && opts.cycle))
				currentPage = 0;
			
			var start = pages[currentPage].start;
			var end = pages[currentPage].end;
			self.lis.hide().slice(start, end).show();
			
			if (direction == 'prev') {
				enableButton('next');
				if (opts.follow && (self.options.selected < start || self.options.selected > (end-1))) self.select(end-1);
				if (!opts.cycle && start <= 0) disableButton('prev');
			} else {
				enableButton('prev');
				if (opts.follow && (self.options.selected < start || self.options.selected > (end-1))) self.select(start);
				if (!opts.cycle && end >= self.length()) disableButton('next');
			}
		}
		
		function disableButton(direction) {
			$('.ui-tabs-paging-'+direction, self.element).addClass('ui-tabs-paging-disabled');
		}
		
		function enableButton(direction) {
			$('.ui-tabs-paging-'+direction, self.element).removeClass('ui-tabs-paging-disabled');
		}
		
		// special function defined to handle IE6 and IE7 resize issues
		function handleResize() {
			if (resizeTimer) clearTimeout(resizeTimer);
			
			if (windowHeight != $(window).height() || windowWidth != $(window).width()) 
				resizeTimer = setTimeout(reinit, 100);
		}
		
		function reinit() {	
			windowHeight = $(window).height();
			windowWidth = $(window).width();
			init();
		}
		
		function destroy() {
			// remove buttons
			$('.ui-tabs-paging-next', self.element).remove();
			$('.ui-tabs-paging-prev', self.element).remove();
			
			// show all tabs
			self.lis.show();
			
			initialized = false;
			
			$(window).unbind('resize', handleResize);
		}
		
		// reconfigure "ui.tabs" add/remove events to reinit paging
		var tabsAdd = self.add;
		self.add = function(url, label, index) {
			// remove paging buttons before adding a tab
			if (initialized)
				destroy();
			
			tabsAdd.apply(this, [url, label, index]);
		    
			if (opts.selectOnAdd) {
				if (index == undefined) index = this.lis.length-1;
				this.select(index);
			}
			// re-initialize paging buttons
			init();
		};
		var tabsRemove = self.remove;
		self.remove = function(index) {
			// remove paging buttons before removing a tab
			if (initialized)
				destroy();
			
			tabsRemove.apply(this, [idMap[index]]);
			
			// re-initialize paging buttons
			init();
		};
		// reconfigure "ui.tabs" select event to change pages if new tab is selected
		var tabsSelect = self.select;
		self.select = function(index) {
			tabsSelect.apply(this, [index]);
			
			// if paging is not initialized or it is not configured to 
			// change pages when a new tab is selected, then do nothing
			if (!initialized || !opts.followOnSelect)
				return;
			
			// find the new page based on index of the tab selected
			for (i in pages) {
				var start = pages[i].start;
				var end = pages[i].end;
				if ((index >= start && index < end) || (idMap[index] >= start && idMap[index] < end)) {
					// if the the tab selected is not within the currentPage of tabs, then change pages
					if (i != currentPage) {
						self.lis.hide().slice(start, end).show();
						
						currentPage = parseInt(i);
						if (currentPage == 0) {
							enableButton('next');
							if (!opts.cycle && start <= 0) disableButton('prev');
						} else {
							enableButton('prev');
							if (!opts.cycle && end >= self.length()) disableButton('next');
						}
					}
					break;
				}
			}
		};
		
        self.reinit = function()
        {
            reinit();
        }
		// add, remove, and destroy functions specific for paging 
		$.extend($.ui.tabs.prototype, {
			pagingDestroy: function() {
				destroy();
			}
		});
		
		init();
	}
});