var lastRan = 1;
var fmtItem = function(imgUrl, url, title, index) {

      var innerHTML =
          '<a id="dhtml-carousel-a-'+index+'" href="' +
          url +
          '"><img id="dhtml-carousel-img-' + index + '" src="' +
          imgUrl +
        '" width="' +
        75 +
        '" height="' +
        75+
        '"/>' +
          title +
          '<\/a>';

    return innerHTML;
};


/**
 * Custom inital load handler. Called when the carousel loads the initial
 * set of data items. Specified to the carousel as the configuration
 * parameter: loadInitHandler
 **/
var loadInitialItems = function(type, args) {

    var start = args[0];
    var last = args[1];

    load(this, start, last);
};

/**
 * Custom load next handler. Called when the carousel loads the next
 * set of data items. Specified to the carousel as the configuration
 * parameter: loadNextHandler
 **/
 var loadNextItems = function(type, args) {

    var start = args[0];
    var last = args[1];
    var alreadyCached = args[2];

    if(!alreadyCached) {
        load(this, start, last);
    }
};

/**
 * Custom load previous handler. Called when the carousel loads the previous
 * set of data items. Specified to the carousel as the configuration
 * parameter: loadPrevHandler
 **/
var loadPrevItems = function(type, args) {
    var start = args[0];
    var last = args[1];
    var alreadyCached = args[2];

    if(!alreadyCached) {
        load(this, start, last);
    }
};

var load = function(carousel, start, last) {
    for(var i=start;i<=last;i++) {
        var liItem = carousel.addItem(i, fmtItem(imageList[i], "#", "Number " + i, i));
/*
        // If you want to add handlers for mouse over, mouse out or other events,
        // here is the pattern
        YAHOO.util.Event.addListener(liItem, "mouseover", function(e) {
        //console.log("mouseover>>"+this.id);
        });
        YAHOO.util.Event.addListener(liItem, "mouseout", function(e) {
            //console.log("mouseout<<"+this.id);
        });
*/
    }
}

/**
 * Custom button state handler for enabling/disabling button state.
 * Called when the carousel has determined that the previous button
 * state should be changed.
 * Specified to the carousel as the configuration
 * parameter: prevButtonStateHandler
 **/
var handlePrevButtonState = function(type, args) {

    var enabling = args[0];
    var leftImage = args[1];
    if(enabling) {
        leftImage.src = "./imagens/left-enabled.gif";
    } else {
        leftImage.src = "./imagens/left-disabled.gif";
    }

};

var carousel; // for ease of debugging; globals generally not a good idea

/**
 * Illustrates stop autoplay
 */
var stopAutoPlay = function(e) {
    // YAHOO.util.Dom.get("status").innerHTML = "Auto Play Stopped!";
    carousel.stopAutoPlay();
};

/**
 * Illustrates start autoplay
 */
var startAutoPlay = function(e) {
    // YAHOO.util.Dom.get("status").innerHTML = "Auto Play Started!";
    carousel.startAutoPlay(4000);
};

var pageLoad = function() {
    carousel = new YAHOO.extension.Carousel("dhtml-carousel", {
               numVisible:      4,
               animationSpeed:  0.4,
               scrollInc:       1,
               navMargin:       0,
               prevElement:     "prev-arrow",
               nextElement:     "next-arrow",
               loadInitHandler:   loadInitialItems,
               loadNextHandler:   loadNextItems,
               loadPrevHandler:   loadPrevItems,
               prevButtonStateHandler:   handlePrevButtonState,
               autoPlay: 4000,
               size: 20,
               wrap:true
  });
};

YAHOO.util.Event.addListener(window, 'load', pageLoad);
YAHOO.util.Event.addListener("stop-button", 'click', stopAutoPlay);
YAHOO.util.Event.addListener("start-button", 'click', startAutoPlay);