var Slideshow =
{
    images: [
        "images/random/r-0001.jpg","images/random/r-0002.jpg","images/random/r-0003.jpg","images/random/r-0004.jpg","images/random/r-0005.jpg","images/random/r-0006.jpg","images/random/r-0007.jpg","images/random/r-0008.jpg","images/random/r-0009.jpg","images/random/r-0010.jpg","images/random/r-0011.jpg","images/random/r-0012.jpg","images/random/r-0013.jpg","images/random/r-0014.jpg","images/random/r-0015.jpg","images/random/r-0016.jpg","images/random/r-0017.jpg","images/random/r-0018.jpg","images/random/r-0019.jpg","images/random/r-0020.jpg","images/random/r-0021.jpg","images/random/r-0022.jpg","images/random/r-0023.jpg","images/random/r-0024.jpg","images/random/r-0025.jpg","images/random/r-0026.jpg","images/random/r-0027.jpg","images/random/r-0028.jpg","images/random/r-0029.jpg","images/random/r-0030.jpg","images/random/r-0031.jpg","images/random/r-0032.jpg","images/random/r-0033.jpg","images/random/r-0034.jpg","images/random/r-0035.jpg","images/random/r-0036.jpg","images/random/r-0037.jpg","images/random/r-0038.jpg","images/random/r-0039.jpg","images/random/r-0040.jpg","images/random/r-0041.jpg","images/random/r-0042.jpg","images/random/r-0043.jpg","images/random/r-0044.jpg","images/random/r-0045.jpg","images/random/r-0046.jpg","images/random/r-0047.jpg","images/random/r-0048.jpg","images/random/r-0049.jpg","images/random/r-0050.jpg","images/random/r-0051.jpg","images/random/r-0052.jpg","images/random/r-0053.jpg","images/random/r-0054.jpg","images/random/r-0055.jpg","images/random/r-0056.jpg","images/random/r-0057.jpg","images/random/r-0058.jpg","images/random/r-0059.jpg","images/random/r-0060.jpg","images/random/r-0061.jpg","images/random/r-0062.jpg","images/random/r-0063.jpg","images/random/r-0064.jpg","images/random/r-0065.jpg","images/random/r-0066.jpg","images/random/r-0067.jpg","images/random/r-0068.jpg","images/random/r-0069.jpg","images/random/r-0070.jpg","images/random/r-0071.jpg","images/random/r-0072.jpg","images/random/r-0073.jpg","images/random/r-0074.jpg","images/random/r-0075.jpg","images/random/r-0076.jpg","images/random/r-0077.jpg","images/random/r-0078.jpg","images/random/r-0079.jpg","images/random/r-0080.jpg","images/random/r-0081.jpg","images/random/r-0082.jpg","images/random/r-0083.jpg","images/random/r-0084.jpg","images/random/r-0085.jpg","images/random/r-0086.jpg","images/random/r-0087.jpg","images/random/r-0088.jpg","images/random/r-0089.jpg","images/random/r-0090.jpg","images/random/r-0091.jpg","images/random/r-0092.jpg","images/random/r-0093.jpg","images/random/r-0094.jpg","images/random/r-0095.jpg","images/random/r-0096.jpg","images/random/r-0097.jpg","images/random/r-0098.jpg","images/random/r-0099.jpg","images/random/r-0100.jpg","images/random/r-0101.jpg","images/random/r-0102.jpg","images/random/r-0103.jpg","images/random/r-0104.jpg","images/random/r-0105.jpg","images/random/r-0106.jpg","images/random/r-0107.jpg","images/random/r-0108.jpg","images/random/r-0109.jpg","images/random/r-0110.jpg","images/random/r-0111.jpg","images/random/r-0112.jpg","images/random/r-0113.jpg","images/random/r-0114.jpg","images/random/r-0115.jpg","images/random/r-0116.jpg","images/random/r-0117.jpg","images/random/r-0118.jpg","images/random/r-0119.jpg","images/random/r-0120.jpg","images/random/r-0121.jpg","images/random/r-0122.jpg","images/random/r-0123.jpg","images/random/r-0124.jpg","images/random/r-0125.jpg","images/random/r-0126.jpg","images/random/r-0127.jpg","images/random/r-0128.jpg","images/random/r-0129.jpg","images/random/r-0130.jpg","images/random/r-0131.jpg","images/random/r-0132.jpg","images/random/r-0133.jpg","images/random/r-0134.jpg","images/random/r-0135.jpg","images/random/r-0136.jpg","images/random/r-0137.jpg","images/random/r-0138.jpg"    ],

    photos: [],

    delay: 4000,

    fadeDuration: 1000,

    getRandomPhoto: function() {
        var min = 0;
        var max = Slideshow.photos.length - 1;
        return Math.round(Math.random() * (max - min) + min);
    },

    setOpacity: function(p, newOpacity) {
        if (typeof p.style.opacity != "undefined") {
            p.style.opacity = newOpacity / 10;
        }
        else if (typeof p.style.filter != "undefined") {
            p.style.filter = "alpha(opacity = " + newOpacity * 10 + ")";
        }
        return;
    },

    fadePhoto: function(p, op) {
        Slideshow.setOpacity(p, op);
        op--;
        if (op <= 0) {
            Slideshow.setOpacity(p, 0);
            // cambia la foto
            Slideshow.changePhoto();
        }
        else {
            window.setTimeout(function() {
                Slideshow.fadePhoto(p, op);
            }, Math.round(Slideshow.fadeDuration / 10));
        }
    },

    changePhoto: function()
    {
        var container = document.getElementById("random-photo");
        if (container) {
            var curImg = container.getElementsByTagName("img")[0];
            var newImg = Slideshow.photos[Slideshow.getRandomPhoto()];
            container.replaceChild(newImg, curImg);
            Slideshow.setOpacity(newImg, 10); // ripristina l'opacità iniziale
            //window.setTimeout(Slideshow.changePhoto, Slideshow.delay);
            window.setTimeout(function() {
                    Slideshow.fadePhoto(newImg, 10);
                }, Slideshow.delay);
        }
    },

    init: function()
    {
        var container = document.getElementById("random-photo");
        if (container) {
            var curImg = container.getElementsByTagName("img")[0];

            // precarica tutte le immagini nell'array di foto
            for (var i = 0; i < Slideshow.images.length; i++) {
                var photo = document.createElement("img");
                photo.setAttribute("src", Slideshow.images[i]);
                photo.setAttribute("alt", "Foto casuale");
                Slideshow.photos.push(photo);
            }

            window.setTimeout(function() {
                    Slideshow.fadePhoto(curImg, 10);
                }, Slideshow.delay);
        }
    }
};

Core.start(Slideshow.init);