( function ( $ ) {

        $.fn.darkbox = function () {
                var shadowFadeInTime  = 200,
                        shadowFadeOutTime = 100,

                        imageFadeInTime       = 400,
                        imageErrorFadeOutTime = 800,

                        darkboxStateClasses =
                                'darkbox-canvas-done darkbox-canvas-load darkbox-canvas-error',

                        boxMargin        = 50, // For cases, when image is bigger than viewport
                        buttonPlaceClass = /mac/i.test( navigator.platform ) ?
                                'darkbox-button-left' :
                                'darkbox-button-right';

                function openBox ( e ) {
                        e.preventDefault();

                        var link = $( this ),
                                frame = $( 'div.darkbox-frame' );

                        $( 'div.darkbox-canvas' ).removeClass( darkboxStateClasses );

                        // NOTE: ?_=timestamp is for Opera 9 and Safari, possible non-caching behaviour
                        var title = link.attr( 'title' ) || "";
                        frame.
                                children( 'div.darkbox-canvas' ).
                                        css( { width: '', marginLeft: '', height: '', marginTop: '' } ).
                                        children( 'img' ).
                                                one( 'error', handleImageLoadError ).
                                                css( { width: '', height: '' } ).
                                                attr( 'src', link.attr( 'href' ) + '?_=' + ( +new Date() ) ).
                                                attr( 'alt', title ).
                                                end().
                                        end().
                                show().
                                children( 'div.darkbox-shadow' ).
                                        animate( { opacity: 0.6 }, shadowFadeInTime );
                }

                function closeBox() {
                        $( 'div.darkbox-shadow' ).animate(
                                { opacity: 0 },
                                shadowFadeOutTime,
                                function () {
                                        $( 'div.darkbox-frame' ).
                                                hide().
                                                children( 'div.darkbox-canvas' ).
                                                        removeClass( darkboxStateClasses ).
                                                        // FIXME: Prevent image download, current solution  is not perfect
                                                        // http://stackoverflow.com/questions/930237/javascript-cancel-stop-image-requests
                                                        children( 'img' ).
                                                                unbind( 'error', handleImageLoadError ).
                                                                attr( 'src', '' ); // Fires error in IE
                                }
                        );
                }

                function handleKey( e ) {
                        // Close darkbox on space (32) and esc (27)
                        if ( 27 === e.which || 32 === e.which ) {
                                        // If darkbox is shown
                                        if ( 0 === $(".darkbox-frame:hidden").length ) {
                                        e.preventDefault();
                                        closeBox();
                                }
                        }
                }

                function handleImageLoadError() {
                        $( 'div.darkbox-canvas' ).addClass( 'darkbox-canvas-error' );
                        setTimeout( closeBox, imageErrorFadeOutTime );
                }

                function handleImageLoad() {
                        var img = $( this ),
                                frame = img.parents( 'div.darkbox-frame' ),
                                // NOTE: we must show canvas to compute dimensions right
                                canvas = img.parents( 'div.darkbox-canvas' ),
                                ratio = 1,
                                img_width = img.width(), img_height = img.height(),
                                frame_width = frame.width(), frame_height = frame.height();

                        // Sometimes IE fires load event before loading image.
                        if ( 0 === img_width && 0 === img_height ) {
                                // TODO: Find the root of evil
                                setTimeout( function (){ img.load(); }, 10 );
                                return;
                        }

                        // We must downsize the image when it is bigger than viewport
                        if (
                                ( img_width > frame_width - boxMargin ) ||
                                ( img_height > frame_height - boxMargin )
                        ) {
                                ratio = Math.min(
                                        ( frame_width - boxMargin ) / img_width,
                                        ( frame_height - boxMargin ) / img_height
                                );

                                img_width = Math.round( img_width * ratio );
                                img_height = Math.round( img_height * ratio );

                                img.css( { width: img_width, height: img_height } );
                        }

                        canvas.
                                addClass( 'darkbox-canvas-load' ).
                                animate( {
                                        width:      img_width,
                                        marginLeft: -img_width / 2,
                                        height:     img_height,
                                        marginTop:  -img_height / 2
                                        }, imageFadeInTime,
                                        function () {
                                                $( this ).
                                                        removeClass( 'darkbox-canvas-load' ).
                                                        addClass( 'darkbox-canvas-done' ).
                                                        children( 'img' ).
                                                                show();
                                        }
                                );
                }

                // Let's add all necessary Darkbox nodes and handlers
                $( '<div class="darkbox-frame"><div class="darkbox-shadow"></div><div class="darkbox-canvas"><img /><div class="darkbox-button" title="Закрыть" ></div></div></div>' ).
                        children( 'div.darkbox-shadow' ).
                                click( closeBox ).
                                end().
                        find( 'div.darkbox-button' ).
                                addClass( buttonPlaceClass ).
                                click( closeBox ).
                                end().
                        find( 'img' ).
                                load( handleImageLoad ).
                                end().
                        appendTo( 'body' ).
                        end();

                // FIXME: need better solution
                // Opera preventDefault for space on keypress
                // Safari reacts on esc only on keydown
                $( document ).
                        keypress( handleKey ).
                        keydown( handleKey );
                this.click( openBox );

                return this; // Support chaining
        };
} ( jQuery ) );