var tempo;
var intervalo = 2000; //Intervalo entra as mudanças de slides. Definido em milisegundos.
var inicio;
var quantDestaques;
var browserName = navigator.appName;

function getId(campo){
    return document.getElementById(campo);
}

function nextSlide() {
    var divs = getId('slides').getElementsByTagName('div');
    var i = 0;
    quantDestaques = getId('quantDestaques').value;
    inicio = getId('inicio').value;
    for (k = 0; k < 6; k++) {
        if (divs[i].className == 'visible') {
            divs[i].className = 'hidden';
            getId('link' + (parseInt(i)+1)).className = 'inativo' ;
            k = 6;
        }
        i++;
    }
    if(parseInt(i) < divs.length){
        divs[i].className = 'visible';
        getId('link' + (parseInt(i)+1)).className = 'ativo';
    }else{
        if((parseInt(inicio) + 6) < parseInt(quantDestaques)){
            MostraDestaques(parseInt(inicio) + 6);
        }else{
            MostraDestaques(0);
        }
    }
}

function upSlides(){
    if(inicio >= 6){
        MostraDestaques(parseInt(inicio) - 6);
    }
}

function downSlides(){
    if((parseInt(inicio) + 6) < parseInt(quantDestaques)){       
        MostraDestaques(parseInt(inicio) + 6);
    }else{
        MostraDestaques(0);
    }
}

function init(){
	tempo = setInterval('nextSlide()', intervalo);
}

function setSlide(link,indice) {
	var divs = getId('slides').getElementsByTagName('div');
	var i;
	for (i = 0; i < divs.length; i++) {
		divs[i].className = 'hidden';
	}
	var lis = getId('ullinks').getElementsByTagName('li');	
	for (i = 0; i < lis.length; i++) {
		lis[i].className = 'inativo';
	}
	link.parentNode.className = 'ativo';
	getId('slide' + indice).className = 'visible';
	clearInterval(tempo);
}

//################# FUNCOES AJAX ###########################
function GetXmlHttpObject(){
    var xmlHttp=null;
    try{
        // Firefox, Opera 8.0+, Safari
        xmlHttp=new XMLHttpRequest();
    }
    catch (e){
        // Internet Explorer
        try{
            xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
        }
        catch (e){
            xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
        }
    }
    return xmlHttp;
}

function stateChanged() {
    if (xmlHttp.readyState==4){
        document.getElementById("destaques").innerHTML=xmlHttp.responseText;
    }
}

function MostraDestaques(inicio){
    xmlHttp=GetXmlHttpObject()
    if (xmlHttp==null){
        alert ("Seu browser não suporta AJAX!");
        return;
    }
    var url="./scripts/destaques.php?inicio="+inicio;
    xmlHttp.onreadystatechange=function(){stateChanged()};
    xmlHttp.open("GET",url,true);
    xmlHttp.send(null);
}