/*************************************************
*
*   project:    - horizontal accordion plugin for jQuery
*   author:     Nicola Hibbert
*   url:        http://nicolahibbert.com/horizontal-accordion-jquery-plugin
*   demo:       http://www.nicolahibbert.com/demo/liteAccordion
*
*   Version:    1.1.3
*   Copyright:  (c) 2010-2011 Nicola Hibbert
*
/*************************************************/
;(function($) {
    
    $.fn.liteAccordion = function(options) {
                
        // defaults
        var defaults = {
            containerWidth : 771,
            containerHeight : 370,
            headerWidth : 31,
            
            firstSlide : 1, 
            onActivate : function() {},
            slideSpeed : 800,
            slideCallback : function() {},          
            
            autoPlay : false,
            pauseOnHover : false, 
            cycleSpeed : 6000,

            theme : 'basic', // basic, light*, dark, stitch*
            rounded : false,
            enumerateSlides : false
        },
        
        // merge defaults with options in new settings object               
            settings = $.extend({}, defaults, options),
    
        // define key variables
            $accordion = this,
            $slides = $accordion.find('li'),
            slideLen = $slides.length,
            slideWidth = settings.containerWidth - (slideLen * settings.headerWidth),
            $header = $slides.children('h2'),
            
        // core utility and animation methods
            utils = {
                getGroup : function(pos, index) {       
                    if (this.offsetLeft === pos.left) {
                        return $header.slice(index + 1, slideLen).filter(function() { return this.offsetLeft === $header.index(this) * settings.headerWidth });
                    } else if (this.offsetLeft === pos.right) {
                        return $header.slice(0, index + 1).filter(function() { return this.offsetLeft === slideWidth + ($header.index(this) * settings.headerWidth) }); 
                    }                   
                },
                nextSlide : function(slideIndex) {
                    var slide = slideIndex + 1 || settings.firstSlide;

                    // get index of next slide
                    return function() {
                        return slide++ % slideLen;
                    }
                },
                play : function(slideIndex) {
                    var getNext = utils.nextSlide((slideIndex) ? slideIndex : ''), // create closure
                        start = function() {
                            $header.eq(getNext()).click();
                        };
                    
                    utils.playing = setInterval(start, settings.cycleSpeed);            
                },
                pause : function() {
                    clearInterval(utils.playing);
                },
                playing : 0,
                sentinel : false
            };      
        
        // set container heights, widths, theme & corner style
        $accordion
            .height(settings.containerHeight)
            .width(settings.containerWidth)
            .addClass(settings.theme)
            .addClass(settings.rounded && 'rounded');
        
        // set tab width, height and selected class
        $header
            .width(settings.containerHeight)
            .height(settings.headerWidth)
            .eq(settings.firstSlide - 1).addClass('selected');
        
        // ie :(
        if ($.browser.msie) {
            if ($.browser.version.substr(0,1) > 8) {
                $header.css('filter', 'none');
            } else if ($.browser.version.substr(0,1) < 7) {
                return false;
            }
        }
        
        // set initial positions for each slide
        $header.each(function(index) {
            var $this = $(this),
                left = index * settings.headerWidth;
                
            if (index >= settings.firstSlide) left += slideWidth;
            
            $this
                .css('left', left)
                .next()
                    .width(slideWidth)
                    .css({ left : left, paddingLeft : settings.headerWidth });
            
            // add number to bottom of tab
            settings.enumerateSlides && $this.append('<b>' + (index + 1) + '</b>');         

        }); 
                
        // bind event handler for activating slides
        $header.click(function(e) {
            var $this = $(this),
                index = $header.index($this),
                $next = $this.next(),
                pos = {
                    left : index * settings.headerWidth,
                    right : index * settings.headerWidth + slideWidth,
                    newPos : 0
                }, 
                $group = utils.getGroup.call(this, pos, index);
                                
            // set animation direction
            if (this.offsetLeft === pos.left) {
                pos.newPos = slideWidth;
            } else if (this.offsetLeft === pos.right) {
                pos.newPos = -slideWidth;
            }
            
            // check if animation in progress
            if (!$header.is(':animated')) {

                // activate onclick callback with slide div as context      
                if (e.originalEvent) {
                    if (utils.sentinel === this) return false;
                    settings.onActivate.call($next);
                    utils.sentinel = this;
                } else {
                    settings.onActivate.call($next);
                    utils.sentinel = false;
                }

                // remove, then add selected class
                $header.removeClass('selected').filter($this).addClass('selected');
            
                // get group of tabs & animate          
                $group
                    .animate({ left : '+=' + pos.newPos }, settings.slideSpeed, function() { settings.slideCallback.call($next) })
                    .next()
                    .animate({ left : '+=' + pos.newPos }, settings.slideSpeed);
                        
            }
        });
            
        // pause on hover           
        if (settings.pauseOnHover) {
            $accordion.hover(function() {
                utils.pause();
            }, function() {
                utils.play($header.index($header.filter('.selected')));
            });
        }
                
        // start autoplay, call utils with no args = start from firstSlide
        settings.autoPlay && utils.play();
        
        return $accordion;
        
    };
    
})(jQuery);