/**
 *  Plugin which is applied on a list of img objects and calls
 *  the specified callback function, only when all of them are loaded (or errored).
 *  @author:  H. Yankov (hristo.yankov at gmail dot com)
 *  @version: 1.0.0 (Feb/22/2010)
 *	http://yankov.us
 */

(function($) {
    $.fn.batchImageLoad = function(options) {
        var images = $(this);
        var originalTotalImagesCount = images.size();
        var totalImagesCount = originalTotalImagesCount;
        var elementsLoaded = 0;

        // Init
        $.fn.batchImageLoad.defaults = {
            loadingCompleteCallback: null,
            imageLoadedCallback: null
        }
        var opts = $.extend({}, $.fn.batchImageLoad.defaults, options);

        // Start
        images.each(function() {
            // The image has already been loaded (cached)
            if ($(this)[0].complete) {
                totalImagesCount--;
                if (opts.imageLoadedCallback) opts.imageLoadedCallback(elementsLoaded, originalTotalImagesCount);
                // The image is loading, so attach the listener
            } else {
                $(this).load(function() {
                    elementsLoaded++;

                    if (opts.imageLoadedCallback) opts.imageLoadedCallback(elementsLoaded, originalTotalImagesCount);

                    // An image has been loaded
                    if (elementsLoaded >= totalImagesCount)
                        if (opts.loadingCompleteCallback) opts.loadingCompleteCallback();
                });
                $(this).error(function() {
                    elementsLoaded++;

                    if (opts.imageLoadedCallback) opts.imageLoadedCallback(elementsLoaded, originalTotalImagesCount);

                    // The image has errored
                    if (elementsLoaded >= totalImagesCount)
                        if (opts.loadingCompleteCallback) opts.loadingCompleteCallback();
                });
            }
        });

        // There are no unloaded images
        if (totalImagesCount <= 0)
            if (opts.loadingCompleteCallback) opts.loadingCompleteCallback();
    };
})(jQuery);