$(document).ready(function(){
	actived = 0;
	count = 1;
	for(i=1;i<6;i++){
		img = new Image();
		img.onLoad = imgLoaded();
		img.src = "images/bg/bg"+i+".jpg";
	}
	
	
});
function imgLoaded(){
	if (actived == 0){
		actived = 1;
		if (GetCookie('intro') == 1){
			$("#intro_effect").fadeOut(10,function(){
				$('#wrapper').fadeIn(200);
				$("#header").fadeTo(200,0.9);
				$("#primary").fadeTo(200,0.8);
				$("#container").fadeTo(200,0.9);
				$("#comments").fadeTo(200,0.9);
				$("#footer").fadeTo(200,0.9);
				BG_fadeEffect();
				setInterval('BG_fadeEffect()',20000);
				//DeleteCookie('intro');
			});
		}else{		
			
			$("#intro_effect").fadeIn(1000,function(){
				$(this).delay(2000).fadeOut("slow",function(){	
					$('#wrapper').delay(500).fadeIn(1000,function(){
						$("#header").fadeTo(1000,0.9,function(){
								$("#primary").fadeTo(1000,0.8,function(){
									$("#container").fadeTo(1000,0.9,function(){
										$("#comments").fadeTo(500,0.9);
										$("#footer").fadeTo(500,0.9);
										createCookie('intro','1',7);
									});
								});
						});
					});
					BG_fadeEffect();
					setInterval('BG_fadeEffect()',20000);
				});	
				
			});
		}
	}
}

function BG_fadeEffect(){
	$("#bg_effect").fadeOut("slow",function(){
		$(this).css("backgroundImage","url(http://www.arki.com.tw/wp-content/themes/twentyten/images/bg/bg"+count+".jpg)");
		$("#bg_effect").fadeIn(3000);
		
	});
	if (count >= 5){
			count = 1;
		}else{
			count ++;
	}
}


//建立一個cookie    
function createCookie(name,value,days) {
 if (days) {
  var date = new Date();
  date.setTime(date.getTime()+(days*24*60*60*1000));
  var expires = "";
  expires=""+date.toGMTString();
 }
 else var expires = "";
 document.cookie = name + "=" + value + "; expires=" + expires;  

}

//讀取cookie
function GetCookie(name)
//讀取Cookie的原始值
{
    var arg = name + "=";
    var alen = arg.length;
    var clen = document.cookie.length;
    var i = 0;
    while (i < clen) {
        var j = i + alen;
        if (document.cookie.substring(i, j) == arg)
            return GetCookieVal(j);
        i = document.cookie.indexOf(" ", i) + 1;
        if (i == 0) break;
    }
    return null;
}
function GetCookieVal(offset)
//獲得Cookie解码后的值
{
    var endstr = document.cookie.indexOf(";", offset);
    if (endstr == -1)
        endstr = document.cookie.length;
    return unescape(document.cookie.substring(offset, endstr));
}


//刪除cookie
function DeleteCookie(name) {
 createCookie(name,"",-1);
}