jquery.jqpagination.js

/*!
 * jqPagination, a jQuery pagination plugin (obviously)
 * Version: 1.4 (26th July 2013)
 *
 * Copyright (C) 2013 Ben Everard
 *
 * http://beneverard.github.com/jqPagination
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *     
 */

(function ($) {
	"use strict";
	
	$.jqPagination = function (el, options) {
	
		// To avoid scope issues, use 'base' instead of 'this'
		// to reference this class from internal events and functions.
	
		var base = this;

		// Access to jQuery and DOM versions of element
		base.$el = $(el);
		base.el = el;
		
		// get input jQuery object
		base.$input = base.$el.find('input');

		// Add a reverse reference to the DOM object
		base.$el.data("jqPagination", base);

		base.init = function () {

			base.options = $.extend({}, $.jqPagination.defaultOptions, options);
			
			// if the user hasn't provided a max page number in the options try and find
			// the data attribute for it, if that cannot be found, use one as a max page number
			
			if (base.options.max_page === null) {
			
				if (base.$input.data('max-page') !== undefined) {
					base.options.max_page = base.$input.data('max-page');
				} else {
					base.options.max_page = 1;
				}
				
			}
			
			// if the current-page data attribute is specified this takes priority
			// over the options passed in, so long as it's a number
			
			if (base.$input.data('current-page') !== undefined && base.isNumber(base.$input.data('current-page'))) {
				base.options.current_page = base.$input.data('current-page');
			}
			
			// remove the readonly attribute as JavaScript must be working by now ;-)
			base.$input.removeAttr('readonly');
			
			// set the initial input value
			// pass true to prevent paged callback form being fired
			
			base.updateInput(true);

			
			 //***************
			// BIND EVENTS
			
			base.$input.on('focus.jqPagination mouseup.jqPagination', function (event) {

				// if event === focus, select all text...
				if (event.type === 'focus') {

					var current_page	= parseInt(base.options.current_page, 10);

					$(this).val(current_page).select();

				}
			
				// if event === mouse up, return false. Fixes Chrome bug
				if (event.type === 'mouseup') {
					return false;
				}
				
			});
			
			base.$input.on('blur.jqPagination keydown.jqPagination', function (event) {
				
				var $self			= $(this),
					current_page	= parseInt(base.options.current_page, 10);
				
				// if the user hits escape revert the input back to the original value
				if (event.keyCode === 27) {
					$self.val(current_page);
					$self.blur();
				}
				
				// if the user hits enter, trigger blur event but DO NOT set the page value
				if (event.keyCode === 13) {
					$self.blur();
				}

				// only set the page is the event is focusout.. aka blur
				if (event.type === 'blur') {
					base.setPage($self.val());
				}
				
			});
			
			base.$el.on('click.jqPagination', 'a', function (event) {
			
				var $self = $(this);

				// we don't want to do anything if we've clicked a disabled link
				// return false so we stop normal link action btu also drop out of this event
				
				if ($self.hasClass('disabled')) {
					return false;
				}

				// for mac + windows (read: other), maintain the cmd + ctrl click for new tab
				if (!event.metaKey && !event.ctrlKey) {
					event.preventDefault();
					base.setPage($self.data('action'));
				}
				
			});
			
		};
		
		base.setPage = function (page, prevent_paged) {
			
			// return current_page value if getting instead of setting
			if (page === undefined) {
				return base.options.current_page;
			}
		
			var current_page	= parseInt(base.options.current_page, 10),
				max_page		= parseInt(base.options.max_page, 10);
							
			if (isNaN(parseInt(page, 10))) {
				
				switch (page) {
				
					case 'first':
						page = 1;
						break;
						
					case 'prev':
					case 'previous':
						page = current_page - 1;
						break;
						
					case 'next':
						page = current_page + 1;
						break;
						
					case 'last':
						page = max_page;
						break;
						
				}
				
			}
			
			page = parseInt(page, 10);
			
			// reject any invalid page requests
			if (isNaN(page) || page < 1 || page > max_page) {

				// update the input element
				base.setInputValue(current_page);
				
				return false;
				
			}
			
			// update current page options
			base.options.current_page = page;
			base.$input.data('current-page', page);
			
			// update the input element
			base.updateInput( prevent_paged );
			
		};
		
		base.setMaxPage = function (max_page, prevent_paged) {
			
			// return the max_page value if getting instead of setting
			if (max_page === undefined) {
				return base.options.max_page;
			}

			// ignore if max_page is not a number
			if (!base.isNumber(max_page)) {
				console.error('jqPagination: max_page is not a number');
				return false;
			}
			
			// ignore if max_page is less than the current_page
			if (max_page < base.options.current_page) {
				console.error('jqPagination: max_page lower than current_page');
				return false;
			}
			
			// set max_page options
			base.options.max_page = max_page;
			base.$input.data('max-page', max_page);
				
			// update the input element
			base.updateInput( prevent_paged );
			
		};
		
		// ATTN this isn't really the correct name is it?
		base.updateInput = function (prevent_paged) {
			
			var current_page = parseInt(base.options.current_page, 10);
							
			// set the input value
			base.setInputValue(current_page);
			
			// set the link href attributes
			base.setLinks(current_page);
			
			// we may want to prevent the paged callback from being fired
			if (prevent_paged !== true) {

				// fire the callback function with the current page
				base.options.paged(current_page);
			
			}
			
		};
		
		base.setInputValue = function (page) {
		
			var page_string	= base.options.page_string,
				max_page	= base.options.max_page;
	
			// this looks horrible :-(
			page_string = page_string
				.replace("{current_page}", page)
				.replace("{max_page}", max_page);
			
			base.$input.val(page_string);
		
		};
		
		base.isNumber = function(n) {
			return !isNaN(parseFloat(n)) && isFinite(n);
		};
		
		base.setLinks = function (page) {
			
			var link_string		= base.options.link_string,
				current_page	= parseInt(base.options.current_page, 10),
				max_page		= parseInt(base.options.max_page, 10);
			
			if (link_string !== '') {
				
				// set initial page numbers + make sure the page numbers aren't out of range
					
				var previous = current_page - 1;
				if (previous < 1) {
					previous = 1;
				}
				
				var next = current_page + 1;
				if (next > max_page) {
					next = max_page;
				}
				
				// apply each page number to the link string, set it back to the element href attribute
				base.$el.find('a.first').attr('href', link_string.replace('{page_number}', '1'));
				base.$el.find('a.prev, a.previous').attr('href', link_string.replace('{page_number}', previous));
				base.$el.find('a.next').attr('href', link_string.replace('{page_number}', next));
				base.$el.find('a.last').attr('href', link_string.replace('{page_number}', max_page));
				
			}

			// set disable class on appropriate links
			base.$el.find('a').removeClass('disabled');

			if (current_page === max_page) {
				base.$el.find('.next, .last').addClass('disabled');
			}

			if (current_page === 1) {
				base.$el.find('.previous, .first').addClass('disabled');
			}

		};
		
		base.callMethod = function (method, key, value) {

			switch (method.toLowerCase()) {

				case 'option':

					// if we're getting, immediately return the value
					if ( value === undefined && typeof key !== "object" ) {
						return base.options[key];
					}

					// set default object to trigger the paged event (legacy opperation)
					var options = {'trigger': true},
					result = false;

					// if the key passed in is an object
					if($.isPlainObject(key) && !value){
						$.extend(options, key)
					}
					else{ // make the key value pair part of the default object
						options[key] = value;
					}

					var prevent_paged = (options.trigger === false);

					// if current_page property is set call setPage
					if(options.current_page !== undefined){
						result = base.setPage(options.current_page, prevent_paged);
					}

					// if max_page property is set call setMaxPage
					if(options.max_page !== undefined){
						result = base.setMaxPage(options.max_page, prevent_paged);
					}

					// if we've not got a result fire an error and return false
					if( result === false ) console.error('jqPagination: cannot get / set option ' + key);
					return result;
					
					break;

				case 'destroy':

					base.$el
						.off('.jqPagination')
						.find('*')
							.off('.jqPagination');

					break;

				default:

					// the function name must not exist
					console.error('jqPagination: method "' + method + '" does not exist');
					return false;

			}

		};

		// Run initializer
		base.init();
		
	};

	$.jqPagination.defaultOptions = {
		current_page	: 1,
		link_string		: '',
		max_page		: null,
		page_string		: 'Page {current_page} of {max_page}',
		paged			: function () {}
	};

	$.fn.jqPagination = function () {

		// get any function parameters
		var self = this,
			$self = $(self),
			args = Array.prototype.slice.call(arguments),
			result = false;

		// if the first argument is a string call the desired function
		// note: we can only do this to a single element, and not a collection of elements

		if (typeof args[0] === 'string') {

			// if we're getting, we can only get value for the first pagination element
			if (args[2] === undefined) {

				result = $self.first().data('jqPagination').callMethod(args[0], args[1]);

			} else {

				// if we're setting, set values for all pagination elements
				$self.each(function(){
					result = $(this).data('jqPagination').callMethod(args[0], args[1], args[2]);
				});

			}

			return result;
		}

		// if we're not dealing with a method, initialise plugin
		self.each(function () {
			(new $.jqPagination(this, args[0]));
		});
		
	};

})(jQuery);