/*
 * jQuery Nivo Zoom v1.0
 * http://nivozoom.dev7studios.com
 *
 * Copyright 2010, Gilbert Pellegrom
 * Free to use and abuse under the MIT license.
 * http://www.opensource.org/licenses/mit-license.php
 * 
 * April 2010
 */

(function($) {

    $.fn.nivoZoom = function(options) {

        //Defaults are below
        var settings = $.extend({}, $.fn.nivoZoom.defaults, options);

        if (settings.overlay) {
            //Disable overly in IE7 due to z-index bug
            if (!($.browser.msie && $.browser.version.substr(0, 1) < 8)) {
                $('body').prepend('<div id="nivoOverlay" />');
                $('#nivoOverlay').css({
                    position: 'fixed',

                    width: '100%',
                    height: '100%',
                    background: settings.overlayColor,
                    opacity: settings.overlayOpacity,
                    'z-index': 90,
                    display: 'none'
                });
            }
        }

        return this.each(function() {
            var context = $(this);

            var nivoZooms = $('a.nivoZoom', context);
            nivoZooms.each(function() {
                var link = $(this);
                if (link.is('a')) {
                    var img = $(this).find('img:first');

                    //Setup link
                    link.css({
                        position: 'relative',
                        display: 'inline-block'
                    });
                    link.attr('title', 'Click to zoom');

                    //Add ZoomHover
                    link.append('<div class="nivoZoomHover" />');
                    var nivoZoomHover = $('.nivoZoomHover', link);
                    nivoZoomHover.css('opacity', '0');
                    link.hover(function() {
                        if (!link.hasClass('zoomed')) {
                            nivoZoomHover.stop().animate({ opacity: settings.zoomHoverOpacity }, 300);
                        }
                    }, function() {
                        if (!nivoZoomHover.hasClass('loading')) {
                            nivoZoomHover.stop().animate({ opacity: 0 }, 300);
                        }
                    });

                    link.bind('click', function() {
                        //Check to see if large image is loaded
                        if ($('img.nivoLarge', link).length == 0) {
                            nivoZoomHover.addClass('loading');
                            loadImg(img, link, function() {
                                nivoZoomHover.removeClass('loading');
                                doZoom(img, link, nivoZoomHover);
                            });
                        } else {
                            doZoom(img, link, nivoZoomHover);
                        }
                        return false;
                    });
                }
            });

        });

        function doZoom(img, link, nivoZoomHover) {
            var imgLarge = $('img.nivoLarge', link);
            if (link.hasClass('zoomed')) {
                //Hide Overlay
                if (settings.overlay) $('#nivoOverlay').fadeOut(settings.speed / 2);
                //Hide Caption
                if ($('.nivoCaption', link).length > 0) {
                    $('.nivoCaption', link).fadeOut(settings.speed / 2);
                }
                //Hide Image
                imgLarge.fadeOut(settings.speed / 2, function() {
                    img.animate({ opacity: 1 }, settings.speed / 2);
                });
                link.removeClass('zoomed');
            } else {
                //Show Overlay
                if (settings.overlay) $('#nivoOverlay').fadeIn(settings.speed / 2);
                //Hide ZoomHover
                nivoZoomHover.css('opacity', '0');
                //Show Image
                img.animate({ opacity: 0 }, settings.speed / 2, function() {
                    imgLarge.fadeIn(settings.speed / 2, function() {
                        showCaption(img, imgLarge, link);
                    });
                });
                link.addClass('zoomed');
            }
        }

        function showCaption(img, imgLarge, link) {
            if ($('.nivoCaption', link).length > 0) {
                var nivoCaption = $('.nivoCaption:first', link);
                if (!nivoCaption.hasClass('nivo-processed')) {
                    //Calculate the image dimensions
                    var imgWidth = img.width();
                    if (imgWidth == 0) imgWidth = img.attr('width');
                    var imgHeight = img.height();
                    if (imgHeight == 0) imgHeight = img.attr('height');
                    var bigImgWidth = imgLarge.width();
                    if (bigImgWidth == 0) bigImgWidth = imgLarge.attr('width');
                    var bigImgHeight = imgLarge.height();
                    if (bigImgHeight == 0) bigImgHeight = imgLarge.attr('height');
                    nivoCaption.css({
                        width: bigImgWidth,
                        opacity: settings.captionOpacity
                    });

                    if (link.hasClass('topRight')) {
                        nivoCaption.css({
                            top: (bigImgHeight - nivoCaption.outerHeight()) + 'px',
                            right: '0px'
                        });
                    }
                    else if (link.hasClass('bottomRight')) {
                        nivoCaption.css({
                            bottom: '0px',
                            right: '0px'
                        });
                    }
                    else if (link.hasClass('bottomLeft')) {
                        nivoCaption.css({
                            bottom: '0px',
                            left: '0px'
                        });
                    }
                    else if (link.hasClass('center')) {
                        nivoCaption.css({
                            top: Math.ceil(imgHeight / 2 - bigImgHeight / 2) + (bigImgHeight - nivoCaption.outerHeight()) + 'px',
                            left: (imgWidth / 2 - bigImgWidth / 2) + 'px'
                        });
                    } else {
                        nivoCaption.css({
                            top: (bigImgHeight - nivoCaption.outerHeight()) + 'px',
                            left: '0px'
                        });
                    }
                    nivoCaption.addClass('nivo-processed');
                }
                nivoCaption.fadeIn(settings.speed / 2);
            }
        }

        function loadImg(img, link, callback) {
            //Load large image
            var newImg = new Image();
            $(newImg).load(function() {
                $(this).addClass('nivoLarge');
                $(this).css({
                    position: 'fixed',
                    display: 'none',
                    'z-index': 99
                });

                //Fix IE7 z-index bug
                if (navigator.userAgent.match(/MSIE \d\.\d+/)) {
                    link.css('z-index', '100');
                }

                if (link.hasClass('topRight')) {
                    $(this).css({
                        top: '0px',
                        right: '0px'
                    });
                }
                else if (link.hasClass('bottomRight')) {
                    $(this).css({
                        bottom: '0px',
                        right: '0px'
                    });
                }
                else if (link.hasClass('bottomLeft')) {
                    $(this).css({
                        bottom: '0px',
                        left: '0px'
                    });
                }
                else if (link.hasClass('center')) {
                    //Calculate the image dimensions
                    var imgWidth = img.width();
                    if (imgWidth == 0) imgWidth = img.attr('width');
                    var imgHeight = img.height();
                    if (imgHeight == 0) imgHeight = img.attr('height');
                    var bigImgWidth = $(this).width();
                    if (bigImgWidth == 0) bigImgWidth = $(this).attr('width');
                    var bigImgHeight = $(this).height();
                    if (bigImgHeight == 0) bigImgHeight = $(this).attr('height');
                    $(this).css({
                        top: (imgHeight / 2 - bigImgHeight / 2) + 'px',
                        left: (imgWidth / 2 - bigImgWidth / 2) + 'px'
                    });
                } else {
                    //Calculate the image dimensions
                    var imgWidth = img.width();
                    var imgHeight = img.height();
                    
                    if (imgWidth >= imgHeight) {
                        $(this).css({
                            top: '10px',
                            left: '25%'
                        });
                    }
                    else if (imgHeight >= imgWidth) {
                        $(this).css({
                            top: '10px',
                            left: 0
                        });
                    }
                }

                $(this).attr('title', 'Click to close');
                link.append($(this));
                callback.call(this);
            }).attr('src', link.attr('href'));
        }
    };

    //Default settings
    $.fn.nivoZoom.defaults = {
        speed: 500,
        zoomHoverOpacity: 0.8,
        overlay: false,
        overlayColor: '#333',
        overlayOpacity: 0.5,
        captionOpacity: 0.8
    };

})(jQuery);