/*Gabriel Birke (birke *at* d-scribe *dot* de)*/
(function($){
$.PaginationCalculator = function(maxentries, opts) {
this.maxentries = maxentries;
this.opts = opts;}
$.extend($.PaginationCalculator.prototype, {
numPages:function() {
return Math.ceil(this.maxentries/this.opts.items_per_page);},
getInterval:function(current_page)  {
var ne_half = Math.floor(this.opts.num_display_entries/2);
var np = this.numPages();
var upper_limit = np - this.opts.num_display_entries;
var start = current_page > ne_half ? Math.max( Math.min(current_page - ne_half, upper_limit), 0 ) : 0;
var end = current_page > ne_half?Math.min(current_page+ne_half + (this.opts.num_display_entries % 2), np):Math.min(this.opts.num_display_entries, np);
return {start:start, end:end};}});
$.PaginationRenderers = {}
$.PaginationRenderers.defaultRenderer = function(maxentries, opts) {
this.maxentries = maxentries;
this.opts = opts;
this.pc = new $.PaginationCalculator(maxentries, opts);}
$.extend($.PaginationRenderers.defaultRenderer.prototype, {
createLink:function(page_id, current_page, appendopts){
var lnk, np = this.pc.numPages();
page_id = page_id<0?0:(page_id<np?page_id:np-1);
appendopts = $.extend({text:page_id+1, classes:""}, appendopts||{});
if(page_id == current_page){
lnk = $("<span class='current'>" + appendopts.text + "</span>");}
else{
lnk = $("<a>" + appendopts.text + "</a>")
.attr('href', this.opts.link_to.replace(/__id__/,page_id));}
if(appendopts.classes){ lnk.addClass(appendopts.classes); }
lnk.data('page_id', page_id);
return lnk;},
appendRange:function(container, current_page, start, end, opts) {
var i;
for(i=start; i<end; i++) {
this.createLink(i, current_page, opts).appendTo(container);}},
getLinks:function(current_page, eventHandler) {
var begin, end,
interval = this.pc.getInterval(current_page),
np = this.pc.numPages(),
fragment = $("<div class='pagination'></div>");
if(this.opts.prev_text && (current_page > 0 || this.opts.prev_show_always)){
fragment.append(this.createLink(current_page-1, current_page, {text:this.opts.prev_text, classes:"prev"}));}
if (interval.start > 0 && this.opts.num_edge_entries > 0){
end = Math.min(this.opts.num_edge_entries, interval.start);
this.appendRange(fragment, current_page, 0, end, {classes:'sp'});
if(this.opts.num_edge_entries < interval.start && this.opts.ellipse_text){
jQuery("<span>"+this.opts.ellipse_text+"</span>").appendTo(fragment);}}
this.appendRange(fragment, current_page, interval.start, interval.end);
if (interval.end < np && this.opts.num_edge_entries > 0){
if(np-this.opts.num_edge_entries > interval.end && this.opts.ellipse_text){
jQuery("<span>"+this.opts.ellipse_text+"</span>").appendTo(fragment);}
begin = Math.max(np-this.opts.num_edge_entries, interval.end);
this.appendRange(fragment, current_page, begin, np, {classes:'ep'});}
if(this.opts.next_text && (current_page < np-1 || this.opts.next_show_always)){
fragment.append(this.createLink(current_page+1, current_page, {text:this.opts.next_text, classes:"next"}));}
$('a', fragment).click(eventHandler);
return fragment;}});
$.fn.pagination = function(maxentries, opts){
opts = jQuery.extend({
items_per_page:1,
num_display_entries:6,
current_page:0,
num_edge_entries:0,
link_to:"#species",
prev_text:"&laquo;",
next_text:"&raquo;",
ellipse_text:"...",
prev_show_always:false,
next_show_always:false,
renderer:"defaultRenderer",
load_first_page:true,
callback:function(){return false;}
},opts||{});
var containers = this,
renderer, links, current_page;
function paginationClickHandler(evt){
var links, 
new_current_page = $(evt.target).data('page_id'),
continuePropagation = selectPage(new_current_page);
if (!continuePropagation) {
evt.stopPropagation();}
return continuePropagation;}
function selectPage(new_current_page) {
containers.data('current_page', new_current_page);
links = renderer.getLinks(new_current_page, paginationClickHandler);
containers.empty();
links.appendTo(containers);
var continuePropagation = opts.callback(new_current_page, containers);
return continuePropagation;}
current_page = opts.current_page;
containers.data('current_page', current_page);
maxentries = (!maxentries || maxentries < 0)?1:maxentries;
opts.items_per_page = (!opts.items_per_page || opts.items_per_page < 0)?1:opts.items_per_page;
if(!$.PaginationRenderers[opts.renderer]){
throw new ReferenceError("Pagination renderer '" + opts.renderer + "' was not found in jQuery.PaginationRenderers object.");}
renderer = new $.PaginationRenderers[opts.renderer](maxentries, opts);
var pc = new $.PaginationCalculator(maxentries, opts);
var np = pc.numPages();
containers.bind('setPage', {numPages:np}, function(evt, page_id) { 
if(page_id >= 0 && page_id < evt.data.numPages) {
selectPage(page_id); return false;}});
containers.bind('prevPage', function(evt){
var current_page = $(this).data('current_page');
if (current_page > 0) {
selectPage(current_page - 1);}
return false;});
containers.bind('nextPage', {numPages:np}, function(evt){
var current_page = $(this).data('current_page');
if(current_page < evt.data.numPages - 1) {
selectPage(current_page + 1);}
return false;});
links = renderer.getLinks(current_page, paginationClickHandler);
containers.empty();
links.appendTo(containers);
if(opts.load_first_page) {
opts.callback(current_page, containers);}}
})(jQuery);