;(function($){
/*******************************************************************************************/    
// jquery.pajinate.js - version 0.4
// A jQuery plugin for paginating through any number of DOM elements
// 
// Copyright (c) 2010, Wes Nolte (http://wesnolte.com)
// Liscensed under the MIT License (MIT-LICENSE.txt)
// http://www.opensource.org/licenses/mit-license.php
// Created: 2010-04-16 | Updated: 2010-04-26
/*******************************************************************************************/
    $.fn.pajinate = function(options){
        // Set some state information
        var current_page = 'current_page';
        var items_per_page = 'items_per_page';
        
        var meta;
    
        // Setup default option values
        var defaults = {
            item_container_id : '.content',
            items_per_page : 10,            
            nav_panel_id : '.page_navigation',
            num_page_links_to_display : 20,            
            start_page : 0,
            wrap_around : false,
            nav_label_first : 'First',
            nav_label_prev : 'Prev',
            nav_label_next : 'Next',
            nav_label_last : 'Last',
            show_first_last: true
        };
        var options = $.extend(defaults,options);
        var $item_container;
        var $page_container;
        var $items;
        var $nav_panels;
        var total_page_no_links;
    
        return this.each(function(){
            $page_container = $(this);
            $item_container = $(this).find(options.item_container_id);
            $items = $page_container.find(options.item_container_id).children();
            meta = $page_container;
            
            // Initialise meta data
            meta.data(current_page,0);
            meta.data(items_per_page, options.items_per_page);
                    
            // Get the total number of items
            var total_items = $item_container.children().size();
            
            // Calculate the number of pages needed
            var number_of_pages = Math.ceil(total_items/options.items_per_page);
            
            // Construct the nav bar
            var more = '<span class="ellipse more">...</span>';
            var less = '<span class="ellipse less">...</span>';
            
            var first = !options.show_first_last ? '' : '<a class="first_link" href="">'+ options.nav_label_first +'</a>';
            var last = !options.show_first_last ? '' : '<a class="last_link" href="">'+ options.nav_label_last +'</a>';
            
            var navigation_html = first;
            navigation_html += '<a class="previous_link" href="">'+ options.nav_label_prev +'</a>'+ less;
            var current_link = 0;
            while(number_of_pages > current_link){
                navigation_html += '<a class="page_link" href="" longdesc="' + current_link +'">'+ (current_link + 1) +'</a>';
                current_link++;
            }
            navigation_html += more + '<a class="next_link" href="">'+ options.nav_label_next +'</a>';
            navigation_html += last;
            
            // And add it to the appropriate area of the DOM    
            $nav_panels = $page_container.find(options.nav_panel_id);            
            $nav_panels.html(navigation_html).each(function(){
            
                $(this).find('.page_link:first').addClass('first');
                $(this).find('.page_link:last').addClass('last');
                
            });
            
            // Hide the more/less indicators
            $nav_panels.children('.ellipse').hide();
            
            // Set the active page link styling
            $nav_panels.find('.previous_link').next().next().addClass('active_page');
            
            /* Setup Page Display */
            // And hide all pages
            $items.hide();
            // Show the first page            
            $items.slice(0, meta.data(items_per_page)).show();
            /* Setup Nav Menu Display */
            // Page number slices
            
            total_page_no_links = $page_container.children(options.nav_panel_id+':first').children('.page_link').size();
            options.num_page_links_to_display = Math.min(options.num_page_links_to_display,total_page_no_links);
            $nav_panels.children('.page_link').hide(); // Hide all the page links
            
            // And only show the number we should be seeing
            $nav_panels.each(function(){
                $(this).children('.page_link').slice(0, options.num_page_links_to_display).show();            
            });
            
            /* Bind the actions to their respective links */
             
            // Event handler for 'First' link
            $page_container.find('.first_link').click(function(e){
                e.preventDefault();
                
                movePageNumbersRight($(this),0);
                goto(0);                
            });            
            
            // Event handler for 'Last' link
            $page_container.find('.last_link').click(function(e){
                e.preventDefault();
                var lastPage = total_page_no_links - 1;
                movePageNumbersLeft($(this),lastPage);
                goto(lastPage);                
            });            
            
            // Event handler for 'Prev' link
            $page_container.find('.previous_link').click(function(e){
                e.preventDefault();
                showPrevPage($(this));
            });
            
            
            // Event handler for 'Next' link
            $page_container.find('.next_link').click(function(e){
                e.preventDefault();                
                showNextPage($(this));
            });
            
            // Event handler for each 'Page' link
            $page_container.find('.page_link').click(function(e){
                e.preventDefault();
                goto($(this).attr('longdesc'));
            });            
            
            // Goto the required page
            goto(parseInt(options.start_page));
            toggleMoreLess();
            if(!options.wrap_around)
                tagNextPrev();
        });
        
        function showPrevPage(e){
            new_page = parseInt(meta.data(current_page)) - 1;                        
            
            // Check that we aren't on a boundary link
            if($(e).siblings('.active_page').prev('.page_link').length==true){
                movePageNumbersRight(e,new_page);
                goto(new_page);
            }else if(options.wrap_around){
                goto(total_page_no_links-1);   
            }
                
        };
            
        function showNextPage(e){
            new_page = parseInt(meta.data(current_page)) + 1;
            
            // Check that we aren't on a boundary link
            if($(e).siblings('.active_page').next('.page_link').length==true){        
                movePageNumbersLeft(e,new_page);
                goto(new_page);
            } else if (options.wrap_around) {
                goto(0);
            }
                
        };
            
        function goto(page_num){
            
            var ipp = meta.data(items_per_page);
            
            var isLastPage = false;
            
            // set location hash 
            window.location.hash = '#page=' + (parseInt(page_num, 10) + 1);
            
            // Find the start of the next slice
            start_from = page_num * ipp;
            
            // Find the end of the next slice
            end_on = start_from + ipp;
            // Hide the current page    
            $items.hide()
                    .slice(start_from, end_on)
                    .show();
            
            // Reassign the active class
            $page_container.find(options.nav_panel_id).children('.page_link[longdesc=' + page_num +']').addClass('active_page')
                                                     .siblings('.active_page')
                                                     .removeClass('active_page');                                         
            
            // Set the current page meta data                            
            meta.data(current_page,page_num);
            
            // Hide the more and/or less indicators
            toggleMoreLess();
            
            // Add a class to the next or prev links if there are no more pages next or previous to the active page
            tagNextPrev();
        };    
        
        // Methods to shift the diplayed index of page numbers to the left or right
        function movePageNumbersLeft(e, new_p){
            var new_page = new_p;
            
            var $current_active_link = $(e).siblings('.active_page');
        
            if($current_active_link.siblings('.page_link[longdesc=' + new_page +']').css('display') == 'none'){
                
                $nav_panels.each(function(){
                            $(this).children('.page_link')
                                .hide() // Hide all the page links
                                .slice(parseInt(new_page - options.num_page_links_to_display + 1) , new_page + 1)
                                .show();        
                            });
            }
            
        } 
        
        function movePageNumbersRight(e, new_p){
            var new_page = new_p;
            
            var $current_active_link = $(e).siblings('.active_page');
            
            if($current_active_link.siblings('.page_link[longdesc=' + new_page +']').css('display') == 'none'){
                                                
                $nav_panels.each(function(){
                            $(this).children('.page_link')
                                .hide() // Hide all the page links
                                .slice( new_page , new_page + parseInt(options.num_page_links_to_display))
                                .show();
                            });
            }
        }
        
        // Show or remove the ellipses that indicate that more page numbers exist in the page index than are currently shown
        function toggleMoreLess(){
                                                     
            if(!$nav_panels.children('.page_link:visible').hasClass('last')){                    
                $nav_panels.children('.more').show();
            }else {
                $nav_panels.children('.more').hide();
            }
            
            if(!$nav_panels.children('.page_link:visible').hasClass('first')){
                $nav_panels.children('.less').show();
            }else {
                $nav_panels.children('.less').hide();
            }            
        }
        
        /* Add the style class ".no_more" to the first/prev and last/next links to allow custom styling */
        function tagNextPrev() {
            if($nav_panels.children('.last').hasClass('active_page')){
                $nav_panels.children('.next_link').add('.last_link').addClass('no_more');
            } else {
                $nav_panels.children('.next_link').add('.last_link').removeClass('no_more');
            }
            
            if($nav_panels.children('.first').hasClass('active_page')){
                $nav_panels.children('.previous_link').add('.first_link').addClass('no_more');
            } else {
                $nav_panels.children('.previous_link').add('.first_link').removeClass('no_more');
            }
        }
        
    };
    
})(jQuery);