$(document).ready(function () {

    // Cesty
    var classBase           = '.orbit';
    var classMove           = classBase + ' .move';
    var classZoom           = classBase + ' .zoom';
    var classItem           = classBase + ' .item';
    var classSource         = classBase + ' .source';
    var classMask           = classBase + ' .mask';

    // Nastaveni

        // Rozmery
        var baseWidth           = 800;
        var baseHeight          = 400;

        // Limit zoomu
        var zoomInLimit         = 200;
        var zoomOutLimit        = 50;

        // Rychlost zoomu
        var zoomSpeed           = 20;

        // Vychozi obrazek
        var startImageIndex    = 40; // Pokud je vetsi nez posledni indexovany, nastavi se na 0

    // Vychozi stavy eventu
    var isMouseWheelUp, isMouseWheelDown, isMouseLeftDown, isMouseRightDown, isMouseMove, isMouseMoveLeft, isMouseMoveRight, mouseMovePrev;

    // CSS
    $(classBase).css({
        'width'     : baseWidth,
        'height'    : baseHeight,
        'position'  : 'relative',
        'overflow'  : 'hidden',
    });
    $(classZoom + ', ' + classMove).css({
        'width'     : '100%',
        'height'    : '100%',
        'position'  : 'absolute',
        'left'      : 0,
        'top'       : 0,
    });
    $(classItem + ' img').hide();
    $(classSource).hide();

    // Prvni a posledni obrazek
    var firstImageIndex = 0;
    var lastImageIndex = 0;

    // Index obrazku
    $(classSource + ' img').each(function(index, value) {
        lastImageIndex++; // Aktualizace posledniho obrazku
        $(this).attr('id', 'orbit-index-'+index);
    });

    // Prvni aktivni obrazek
    var activeImageIndex = ((startImageIndex !== 0 && startImageIndex <= lastImageIndex) ? startImageIndex : firstImageIndex);
    var firstImageSrc = $(classSource + ' img#orbit-index-'+activeImageIndex+'').attr('src');

    // Nezbytne HTML
    $(classBase).append('<div class="move"><div class="zoom"><div class="item" style="background-image:url('+firstImageSrc+');"><img src="'+firstImageSrc+'"></div></div></div>');

    // Funkce rotace
    function orbitRotate(data) {

        // Aktivni obrazek

        var activeImageSrc = $(classSource + ' img#orbit-index-'+activeImageIndex+'').attr('src');

        // Dalsi
        if(data == 'next') {
            if(activeImageIndex == lastImageIndex) {
                activeImageIndex = firstImageIndex;
            } else {
                activeImageIndex++;
            }
        }

        // Predchozi
        if(data == 'prev') {
            if(activeImageIndex == firstImageIndex) {
                activeImageIndex = lastImageIndex;
            } else {
                activeImageIndex--;
            }
        }

        $(classItem).css('background-image', 'url('+activeImageSrc+')');
        $(classItem + ' img').attr('src', activeImageSrc);

    }

    // Funkce priblizeni a oddaleni
    function orbitZoom(data) {

        // Kontrola nastaveni
        if(zoomInLimit < 100) zoomInLimit = 100;
        if(zoomOutLimit > 100) zoomInLimit = 100;

        // Puvodni velikost
        var origWidth = $(classZoom).parent().width();
        var origHeight = $(classZoom).parent().height();

        // Stavajici velikost
        var curWidth = $(classZoom).width();
        var curHeight = $(classZoom).height();

        // Koeficient rychlosti
        var cWidth = (curWidth / zoomSpeed);
        var cHeight = (curHeight / zoomSpeed);

        // Maxinalni, minimalni sirka a vyska
        var maxWidth = ((origWidth / 100) * zoomInLimit);
        var maxHeight = ((origHeight / 100) * zoomInLimit);
        var minWidth = ((origWidth / 100) * zoomOutLimit);
        var minHeight = ((origHeight / 100) * zoomOutLimit);

        // Pusteni dle smeru
        if(data == 'in') {
            curWidth = Math.round(curWidth + cWidth);
            curHeight = Math.round(curHeight + cHeight);
        }
        if(data == 'out') {
            curWidth = Math.round(curWidth - cWidth);
            curHeight = Math.round(curHeight - cHeight);
        }

        // Kontrola a zapis CSS
        if (maxWidth > curWidth && maxHeight > curHeight && minWidth < curWidth && minHeight < curHeight) {
            $(classZoom).css({
                'width'         : curWidth,
                'height'        : curHeight,
                'left'          : '50%',
                'top'           : '50%',
                'margin-left'   : -(curWidth / 2),
                'margin-top'    : -(curHeight / 2),
            });
        }

    }

    // Funkce pohyb
    function orbitMove(pageX, pageY) {
        $(classMove).css({
            'left' : pageX - $(this).outerHeight() / 2,
            'top' : pageY - $(this).outerHeight() / 2,
        });
    }







    // Event (mousewheel)
    $(classBase).on('mousewheel DOMMouseScroll wheel', function(e){

        // Plneni promennych dle cinosti
        if(e.type == 'mousewheel' || e.type == 'wheel') { // IE, Safari, Chrome, Opera
            if(e.originalEvent.wheelDelta < 0) {
                isMouseWheelDown = true;
                isMouseWheelUp = false;
            } else if (e.originalEvent.wheelDelta > 0) {
                isMouseWheelUp = true;
                isMouseWheelDown = false;
            }
        }
        if(e.type == 'DOMMouseScroll') { // Firefox
            if(e.originalEvent.detail > 0) {
                isMouseWheelDown = true;
                isMouseWheelUp = false;
            } else if (e.originalEvent.detail < 0) {
                isMouseWheelUp = true;
                isMouseWheelDown = false;
            }
        }

                // Vynulovani promennych pri necinosti
                clearTimeout($.data(this, 'stopTimer'));
                $.data(this, 'stopTimer', setTimeout(function() {
                    isMouseWheelUp = false;
                    isMouseWheelDown = false;
                }, 100));

                // Spousteni funkci
                if(isMouseWheelUp == true) orbitZoom('in');
                if(isMouseWheelDown == true) orbitZoom('out');

            });

            // Event (mousewheel)
            $(classBase).on('mousedown mouseup mousemove contextmenu', function(e){

                // Mousedown, mouseup
                if(e.type == 'mousedown') {
                    if(e.which == 1) isMouseLeftDown = true;
                    if(e.which == 3) isMouseRightDown = true;
                }
                if(e.type == 'mouseup') {
                    if(e.which == 1) isMouseLeftDown = false;
                    if(e.which == 3) isMouseRightDown = false;
                }
                if(e.type == 'mousemove') {
                    isMouseMove = true;
                    if(mouseMovePrev < e.pageX) {
                        isMouseMoveLeft = false;
                        isMouseMoveRight = true;
                    } else {
                        isMouseMoveLeft = true;
                        isMouseMoveRight = false;
                    }
                    mouseMovePrev = e.pageX;

                    // Vynulovani promennych pri necinosti
                    clearTimeout($.data(this, 'stopTimer'));
                    $.data(this, 'stopTimer', setTimeout(function() {
                        isMouseMove = false;
                        isMouseMoveLeft = false;
                        isMouseMoveRight = false;
                    }, 100));

                }
                if(e.type == 'contextmenu') {
                    return false;
                }

                // Spousteni funkci
                if(isMouseLeftDown && isMouseMoveLeft) orbitRotate('next');
                if(isMouseLeftDown && isMouseMoveRight) orbitRotate('prev');
                // if(isMouseRightDown && isMouseMove) orbitMove(e.pageX, e.pageY);

            });

        });