var index = 0;
$slideshow = {
    context: false,
    tabs: true,
    timeout: 6000,      // 次のイメージに移動する前の静止時間
    slideSpeed: 1000,   // time it takes to slide in each slide (in ms)
    tabSpeed: 300,      // time it takes to slide in each slide (in ms) when clicking through tabs
    fx: 'scrollLeft',   // the slide effect to use
    
    init: function() {
        // set the context to help speed up selectors/improve performance
        this.context = $('#slideshow');
        
        // set tabs to current hard coded navigation items
        this.tabs = $('ul.slides-nav li', this.context);
        
        // remove hard coded navigation items from DOM 
        // because they aren't hooked up to jQuery cycle
        this.tabs.remove();
        
        // prepare slideshow and jQuery cycle tabs
        this.prepareSlideshow();
    },
    
    prepareSlideshow: function() {
    	if(!$('#slide_list li') || ($('#slide_list li').length == 0)) {
    		return;
    	}

         $('#slide_list li')[0].style.display = 'none';
         $('#slide_list li')[0].style.visibility = 'visible';
         // [0]
         index = Math.floor( Math.random() * $('#slide_list li').length * 1);
         if(index >= $('#slide_list li').length) {
         	 index = 0;
         }
         $('#slide_list li')[index].style.display = 'block';
    },
    
    prepareTabs: function(i, slide) {
        // return markup from hardcoded tabs for use as jQuery cycle tabs
        // (attaches necessary jQuery cycle events to tabs)
        return $slideshow.tabs.eq(i);
    },

    activateTab: function(currentSlide, nextSlide) {
        // get the active tab
        var activeTab = $('a[href="#' + nextSlide.id + '"]', $slideshow.context);
        
        // if there is an active tab
        if(activeTab.length) {
            // remove active styling from all other tabs
            $slideshow.tabs.removeClass('on');
            
            // add active styling to active button
            activeTab.parent().addClass('on');
        }            
    }            
};


$(function() {
    // add a 'js' class to the body
    $('body').addClass('js');
    
    // initialise the slideshow when the DOM is ready
    $slideshow.init();
});