// 高亮当前导航点
function slidenavHighlight($next) {
	$("#slidenav a").removeClass("cur");
	var currentNum = $("#slideshow div").index($next);
	var $highlightNav = $("#slidenav a:first");
	for( i = 0; i <= currentNum; i++){
		if( i == currentNum )
			$highlightNav.addClass("cur");
		else
			$highlightNav = $highlightNav.next(); 
	}
}

// 默认幻灯播放
function slideSwitch() {
	var $current = $("#slideshow div.current");
	if ( $current.length == 0 ) $current = $("#slideshow div:last");
	var $next =  $current.next().length ? $current.next() : $("#slideshow div:first");
	$current.addClass('prev');
	$next.css({opacity: 0.0}).addClass("current").animate({opacity: 1.0}, 800, function() {
	$current.removeClass("current prev");
		});
	slidenavHighlight($next);
}

// 向左播放幻灯
function slideSwitchleft(){
	var $current = $("#slideshow div.current");
	if ( $current.length == 0 ) $current = $("#slideshow div:first");
	var $next = ( $current.prev().attr("class") != "rightImg" ) ? $current.prev() : $("#slideshow div:last");
	$current.addClass('prev');
	$next.css({opacity: 0.0}).addClass("current").animate({opacity: 1.0}, 800, function() {
	$current.removeClass("current prev");
		});
	slidenavHighlight($next);
}

function slideSwitchto() {
	var $current = $("#slideshow div.current");
	if ( $current.length == 0 ) $current = $("#slideshow div:last");
	var $next =  $current.next().length ? $current.next() : $("#slideshow div:first");
	$current.addClass('prev');
	$next.css({opacity: 0.0}).addClass("current").animate({opacity: 1.0}, 0, function() {
	$current.removeClass("current prev");
		});
	slidenavHighlight($next);
}

function slideSwitchleftto(){
	var $current = $("#slideshow div.current");
	if ( $current.length == 0 ) $current = $("#slideshow div:first");
	var $next = ( $current.prev().attr("class") != "rightImg" ) ? $current.prev() : $("#slideshow div:last");
	$current.addClass('prev');
	$next.css({opacity: 0.0}).addClass("current").animate({opacity: 1.0}, 0, function() {
	$current.removeClass("current prev");
		});
	slidenavHighlight($next);
}

function slideSwitchtowhat(slideindex){
	var $current = $("#slideshow div.current");
	var $slideNum = slideindex - $("#slideshow div").index($current);
	if( $slideNum < 0 ){
		for( i = 0; i < 0 - ($slideNum) ; i++ )
			setTimeout('slideSwitchleftto()',0);
	} else if( $slideNum > 0 ){
		for( i = 0; i < $slideNum; i++ )
			setTimeout('slideSwitchto()',0);
	}
}

$(function() {
	$("#slideshow div:first").addClass("current");
	$("#slideshow span").css("opacity","0.7");
	$(".current").css("opacity","1.0");
	
	// 设定时间为3秒
   autoSlide = setInterval( "slideSwitch()", 3000 ); 

   // 鼠标悬停时停止换图
	$("#slideshow").mouseenter(function(){
		clearInterval(autoSlide)
	});
	$("#slideshow").mouseleave(function(){
		autoSlide = setInterval( "slideSwitch()", 3000 );
	});

	// 换图
	$("a.leftImg").bind("click",function(){
		if( !($(".current").is(":animated")))
			slideSwitchleft();
		return false;
	});
	
	$("a.rightImg").bind("click",function(){
		if( !($(".current").is(":animated")))
			slideSwitch();
		return false;
	});

	// 导航
	var $imgNum = $("#slideshow div").length;
	for( i = 0; i < $imgNum; i++ ){
		$(".slidenavcon").append('<a href="#"><span>&#149;</span></a>');
	}
	$("#slidenav a:first").addClass("cur");	
	
	$("#slidenav a").bind("click",function(){
		clearInterval(autoSlide);
		var slideindex = $("#slidenav a").index(this);
		if( !($(".current").is(":animated")))	
			slideSwitchtowhat(slideindex);
		autoSlide = setInterval( "slideSwitch()", 3000 );
		return false;
	});
 
});