/**
 * 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 = "upload/buttons/left-enabled.gif";  
    } else {
        leftImage.src = "upload/buttons/left-disabled.gif";
    }
    
};

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

/**
 * You must create the carousel after the page is loaded since it is
 * dependent on an HTML element (in this case 'dhtml-carousel'.) See the
 * HTML code below.
 */
var pageLoad = function() 
{
    carousel = new YAHOO.extension.Carousel("dhtml-carousel", 
        {
            numVisible:        1,
            animationSpeed:   2,/*Orig: 0,7, je höher, desto langsamer*/
            scrollInc:         1,
            navMargin:         0,
            prevElement:     "prev-arrow",
            nextElement:     "next-arrow",
            loadInitHandler:   loadInitialItems,
            loadNextHandler:   loadNextItems,
            loadPrevHandler:   loadPrevItems,
            prevButtonStateHandler:   handlePrevButtonState,
            autoPlay: 2000,
            size:5,
            wrap:true
        }
    );
    

};
/**
 * 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(2000);
};

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