window.onload = function() {
    SiteScrolling.init();
    //scrollTips.init(); //ABILITA LA ROTELLINA DEL MOUSE;
}

var SiteScrolling = {
    speed: 25,      //set here the scroll speed: when this value increase, the speed decrease. 
    maxStep: 300,  //set here the "uniform motion" step for long distances
    brakeK: 3, 	 //set here the coefficient of slowing down
    hash: null,
    currentBlock: null,
    requestedX: 0,
    requestedY: 0,
    scrollStep: 0,
    init: function() {
        var lnks = document.getElementsByTagName('a');
        for (var i = 0, lnk; lnk = lnks[i]; i++) {
            if ((lnk.href && lnk.href.indexOf('#') != -1) && ((lnk.pathname == location.pathname) ||
			('/' + lnk.pathname == location.pathname)) && (lnk.search == location.search)) {
                addEvent(lnk, 'click', SiteScrolling.initScroll, false);
                lnk.onclick = function() { return false; } // Safari
            }
        }
    },
    getTarget: function(target) {
        while (target.tagName.toLowerCase() != 'a')
            target = target.parentNode;
        return target;
    },
    getElementXpos: function(el) {
        var x = 0;
        while (el.offsetParent) {
            x += el.offsetLeft;
            el = el.offsetParent;
        } return x;
    },
    getElementYpos: function(el) {
        var y = 0;
        while (el.offsetParent) {
            y += el.offsetTop
            el = el.offsetParent;
        } return y;
    },
    getScrollLeft: function() {
        if (document.all) return (document.documentElement.scrollLeft) ? document.documentElement.scrollLeft : document.body.scrollLeft;
        else return window.pageXOffset;
    },
    getWindowWidth: function() {
        if (window.innerWidth) return window.innerWidth;
        if (document.documentElement && document.documentElement.clientWidth) return document.documentElement.clientWidth;
    },
    getDocumentWidth: function() {
        if (document.width) return document.width;
        if (document.body.offsetWidth) return document.body.offsetWidth;
    },
    getScrollTop: function() {
        if (document.all) return (document.documentElement.scrollTop) ? document.documentElement.scrollTop : document.body.scrollTop;
        else return window.pageYOffset;
    },
    getWindowHeight: function() {
        if (window.innerHeight) return window.innerHeight;
        if (document.documentElement && document.documentElement.clientHeight) return document.documentElement.clientHeight;
    },
    getDocumentHeight: function() {
        if (document.height) return document.height;
        if (document.body.offsetHeight) return document.body.offsetHeight;
    },
    initScroll: function(e) {
        var targ;
        if (!e) var e = window.event;
        if (e.target) targ = e.target;
        else if (e.srcElement) targ = e.srcElement;
        targ = SiteScrolling.getTarget(targ);  //a fix by Skid X
        SiteScrolling.hash = targ.href.substr(targ.href.indexOf('#') + 1, targ.href.length);
        SiteScrolling.currentBlock = document.getElementById(SiteScrolling.hash);
        if (!SiteScrolling.currentBlock) return;
        SiteScrolling.requestedX = SiteScrolling.getElementXpos(SiteScrolling.currentBlock);
        SiteScrolling.requestedY = SiteScrolling.getElementYpos(SiteScrolling.currentBlock);

        SiteScrolling.scroll(targ);
        return false;
    },
    scrollTo: function(destination) {
        SiteScrolling.hash = destination;
        SiteScrolling.currentBlock = document.getElementById(destination);
        if (!SiteScrolling.currentBlock) return;
        SiteScrolling.requestedX = SiteScrolling.getElementXpos(SiteScrolling.currentBlock);
        SiteScrolling.requestedY = SiteScrolling.getElementYpos(SiteScrolling.currentBlock);

        SiteScrolling.scroll(destination);
        return false;
    },
    scroll: function(targ) {
        var left = SiteScrolling.getScrollLeft();
        var top = SiteScrolling.getScrollTop();
        while (true) {
            if (SiteScrolling.scrollStep == 0) {
                if (SiteScrolling.requestedX > left) {
                    var endDistanceX = Math.round((SiteScrolling.getDocumentWidth() - (left + SiteScrolling.getWindowWidth())) / SiteScrolling.brakeK);
                    endDistanceX = Math.min(Math.round((SiteScrolling.requestedX - left) / SiteScrolling.brakeK), endDistanceX);
                    var offsetX = Math.max(2, Math.min(endDistanceX, SiteScrolling.maxStep));
                }
                else {
                    var offsetX = -Math.min(Math.abs(Math.round((SiteScrolling.requestedX - left) / SiteScrolling.brakeK)), SiteScrolling.maxStep);
                }

                window.scrollTo(left + offsetX, top);
                if (Math.abs(left - SiteScrolling.requestedX) <= 1 || SiteScrolling.getScrollLeft() == left) {
                    window.scrollTo(SiteScrolling.requestedX, SiteScrolling.getScrollTop());
                    SiteScrolling.scrollStep = 1;
                    //setTimeout(SiteScrolling.scroll, SiteScrolling.speed);
                }
                else {
                    setTimeout(SiteScrolling.scroll, SiteScrolling.speed);
                    break;
                }
            }
            else if (SiteScrolling.scrollStep == 1) {
                if (SiteScrolling.requestedY > top) {
                    var endDistanceY = Math.round((SiteScrolling.getDocumentHeight() - (top + SiteScrolling.getWindowHeight())) / SiteScrolling.brakeK);
                    endDistanceY = Math.min(Math.round((SiteScrolling.requestedY - top) / SiteScrolling.brakeK), endDistanceY);
                    var offsetY = Math.max(2, Math.min(endDistanceY, SiteScrolling.maxStep));
                }
                else {
                    var offsetY = -Math.min(Math.abs(Math.round((SiteScrolling.requestedY - top) / SiteScrolling.brakeK)), SiteScrolling.maxStep);
                }
                window.scrollTo(left, top + offsetY);
                if (Math.abs(top - SiteScrolling.requestedY) <= 1 || SiteScrolling.getScrollTop() == top) {
                    window.scrollTo(SiteScrolling.getScrollLeft(), SiteScrolling.requestedY);
                    SiteScrolling.scrollStep = 2;
                    //setTimeout(SiteScrolling.scroll, SiteScrolling.speed);
                }
                else {
                    setTimeout(SiteScrolling.scroll, SiteScrolling.speed);
                    break;
                }
            }

            else if (SiteScrolling.scrollStep == 2) {
                SiteScrolling.scrollStep = 0;
                if (typeof XULDocument != 'undefined' || !document.all || window.opera)
                    location.hash = SiteScrolling.hash;
                SiteScrolling.hash = null;
                break;
            }


        }
        //optional instructions: you can add an effect to enlight after the scroll the selected section.
        //uncomment this line below if you want to change the opacity:
        //mark.change_opacity(SiteScrolling.hash);

        //you can also call the function "mark.change_colors(SiteScrolling.hash, fps, (duration in sec), #(color in hex), #(color in hex))" to change background color of selected section
    }

}

/* the mouse scrolling doesn't work with Opera, that hasn't a event associated to the mouse wheel */

var scrollTips = {
    dx: null,
    init: function() {
        if (window.addEventListener) {
            window.addEventListener("DOMMouseScroll", this.mouseScroll, false);
        } else document.attachEvent("onmousewheel", this.mouseScroll);
        var left = document.getElementById('left');
        addEvent(left, 'mouseover', function() { this.dx = setInterval('scrollTips.arrowScroll(0)', 100); return false; });
        addEvent(left, 'mouseout', function() { clearInterval(this.dx); return false; });
        var right = document.getElementById('right');
        addEvent(right, 'mouseover', function() { this.dx = setInterval('scrollTips.arrowScroll(1)', 100); return false; });
        addEvent(right, 'mouseout', function() { clearInterval(this.dx); return false; });
    },
    mouseScroll: function(e) {
        if (!e) var e = window.event;
        if (e.wheelDelta <= 0 || e.detail >= 0) {
            window.scrollBy(80, 0);
        } else window.scrollBy(-80, 0);
    },
    arrowScroll: function(val) {
        if (val == 1) {
            window.scrollBy(70, 0);
        } else {
            window.scrollBy(-70, 0)
        }
    }
}

var mark = {        //first four functions are based on The Fade Anything Technique by Adam Michela 
    valop: 100,
    req: 0,
    make_hex: function(r, g, b) {
        r = r.toString(16); if (r.length == 1) r = '0' + r;
        g = g.toString(16); if (g.length == 1) g = '0' + g;
        b = b.toString(16); if (b.length == 1) b = '0' + b;
        return "#" + r + g + b;
    },
    change_colors: function(id, fps, duration, from, to) {
        var frames = Math.round(fps * (duration / 1000));
        var interval = duration / frames;
        var delay = interval;
        var frame = 0;
        if (from.length < 7) from += from.substr(1, 3);
        if (to.length < 7) to += to.substr(1, 3);
        var rf = parseInt(from.substr(1, 2), 16);
        var gf = parseInt(from.substr(3, 2), 16);
        var bf = parseInt(from.substr(5, 2), 16);
        var rt = parseInt(to.substr(1, 2), 16);
        var gt = parseInt(to.substr(3, 2), 16);
        var bt = parseInt(to.substr(5, 2), 16);
        var r, g, b, h;
        while (frame < frames) {
            r = Math.floor(rf * ((frames - frame) / frames) + rt * (frame / frames));
            g = Math.floor(gf * ((frames - frame) / frames) + gt * (frame / frames));
            b = Math.floor(bf * ((frames - frame) / frames) + bt * (frame / frames));
            h = this.make_hex(r, g, b);
            setTimeout("mark.set_img_bgcolor('" + id + "','" + h + "')", delay);
            frame++;
            delay = interval * frame;
        }
        setTimeout("mark.set_img_bgcolor('" + id + "','" + to + "')", delay);
    },

    set_img_bgcolor: function(id, c) {
        if (document.getElementById(id).getElementsByTagName('img')[0]) {
            var o = document.getElementById(id).getElementsByTagName('img')[0];
            o.style.backgroundColor = c;
        } else return;
    },
    get_img_bgcolor: function(id) {
        var o = document.getElementById(id).getElementsByTagName('img')[0];
        while (o) {
            var c;
            if (window.getComputedStyle) c = window.getComputedStyle(o, null).getPropertyValue("background-color");
            if (o.currentStyle) c = o.currentStyle.backgroundColor;
            if ((c != "" && c != "transparent") || o.tagName == "BODY") { break; }
            o = o.parentNode;
        }
        if (c == undefined || c == "" || c == "transparent") c = "#FFFFFF";
        var rgb = c.match(/rgb\s*\(\s*(\d{1,3})\s*,\s*(\d{1,3})\s*,\s*(\d{1,3})\s*\)/);
        if (rgb) c = this.make_hex(parseInt(rgb[1]), parseInt(rgb[2]), parseInt(rgb[3]));
        return c;
    },
    change_opacity: function(el) {
        if (!(/^menu/.test(el))) {
            var post = document.getElementById(el);
            if (mark.valop > 10 && mark.req == 0) {
                mark.valop -= 10;
                mark.set_opacity(post, mark.valop);
                if (mark.valop == 10) { mark.req = 1 };
            } else
                if (mark.valop < 100 && mark.req == 1) {
                mark.valop += 10;
                mark.set_opacity(post, mark.valop);
                if (mark.valop == 100) { mark.req = 2 };
            }
            if (mark.req != 2) {
                setTimeout("mark.change_opacity('" + el + "')", 50);
            }
            else { mark.set_opacity(post, 9999); mark.req = 0; return; }
        }
    },
    set_opacity: function(post, val) {
        post.style.opacity = '0.' + val;
        post.style.filter = "alpha(opacity=" + val + ")";
    }
}

function addEvent(obj, type, fn) {
    if (obj.addEventListener)
        obj.addEventListener(type, fn, false);
    else if (obj.attachEvent) {
        obj["e" + type + fn] = fn;
        obj[type + fn] = function() { obj["e" + type + fn](window.event); }
        obj.attachEvent("on" + type, obj[type + fn]);
    }
}

function removeEvent(obj, type, fn) {
    if (obj.removeEventListener)
        obj.removeEventListener(type, fn, false);
    else if (obj.detachEvent) {
        obj.detachEvent("on" + type, obj[type + fn]);
        obj[type + fn] = null;
        obj["e" + type + fn] = null;
    }
}