/*
* Author:      Marco Kuiper (http://www.marcofolio.net/)
*              Sylvain Papet (http://www.com-ocean.com/)
*/

(function ($) {
    $.bgimgSlideshow = { version: '1.0.0' };

    $.fn.bgimgSlideshow = function (options) {
        options = jQuery.extend({
            slideshowSpeed: 6000,
            photos: [],
            markup: '<div id="background">\
  <div id="bis_images">\
    <div id="bis_image1" class="bis_image"></div>\
    <div id="bis_image2" class="bis_image"></div>\
  </div>\
  <div id="bis_container">\
    <div id="bis_nav">\
       <div id="bis_back" class="bis_btn"></div>\
       <div id="bis_control" class="bis_btn"></div>\
       <div id="bis_next" class="bis_btn"></div>\
    </div>\
    <div id="bis_caption">\
      <p class="bis_title">\
         <a href="#" id="bis_titlelink"></a>\
      </p>\
    </div>\
  </div>\
</div>'
        }, options);

        var interval;
        var activeContainer = 1;
        var currentImg = 0;
        var started = false;
        var animating = false;
        var currentZindex = -1;

        var image_cache = [];

        $.bgimgSlideshow.preLoadImage = function () {
            var args_len = arguments.length;
            for (var i = args_len; i--; ) {
                var cacheImage = document.createElement('img');
                cacheImage.src = arguments[i];
                image_cache.push(cacheImage);
            }
        }

        $.bgimgSlideshow.preLoadPhotoObjects = function (photoObjects) {
            for (i in photoObjects) {
                $.bgimgSlideshow.preLoadImage(photoObjects[i].image, photoObjects[i].image);
            }
        }

        $.bgimgSlideshow.initialize = function () {
            $('body').prepend(options.markup);
            $.bgimgSlideshow.preLoadPhotoObjects(options.photos);

            // Backwards navigation
            $("#bis_back").click(function () {
                $.bgimgSlideshow.stopSlideshow();
                $.bgimgSlideshow.navigate("back");
            });

            // Forward navigation
            $("#bis_next").click(function () {
                $.bgimgSlideshow.stopSlideshow();
                $.bgimgSlideshow.navigate("next");
            });

            $("#bis_control").click(function () {
                if (started) {
                    $.bgimgSlideshow.stopSlideshow();
                }
                else {
                    $.bgimgSlideshow.startSlideshow();
                }
            });
            $.bgimgSlideshow.startSlideshow();
        };

        $.bgimgSlideshow.navigate = function (direction) {
            // Check if no animation is running. If it is, prevent the action
            if (animating) {
                return;
            }

            // Check which current image we need to show
                        if (direction == "next") {
                            currentImg++;
                            if (currentImg == photos.length + 1) {
                                currentImg = 1;
                            }
                        } else {
                            currentImg--;
                            if (currentImg == 0) {
                                currentImg = photos.length;
                            }
                        }

            //currentImg = Math.floor(Math.random() * photos.length);
            
            // Check which container we need to use
            var currentContainer = activeContainer;
            if (activeContainer == 1) {
                activeContainer = 2;
            } else {
                activeContainer = 1;
            }
            //alert(photos[Math.floor(Math.random() * photos.length)]);
            $.bgimgSlideshow.showImage((currentImg - 1), currentContainer, activeContainer);
        };

        $.bgimgSlideshow.showImage = function (numImg, currentContainer, activeContainer) {
            var photoObject = options.photos[numImg];
            animating = true;

            // Make sure the new container is always on the background
            currentZindex--;

            // Set the background image of the new active container
            $("#bis_image" + activeContainer).css({
                "background-image": "url(" + photoObject.image + ")",
                "display": "block",
                "z-index": currentZindex
            });

            if (photoObject.url) {
                $("#bis_caption p").html('<a href="' + photoObject.url + '" target="_blank">' + photoObject.title + '</a>');
            }
            else {
                $("#bis_caption p").html(photoObject.title);
            }

            // Fade out the current container
            // and display the header text when animation is complete
            $("#bis_image" + currentContainer).fadeOut(2000, function () {
                setTimeout(function () {
                    animating = false;
                }, 500);
            });
        };

        $.bgimgSlideshow.stopSlideshow = function () {
            // Change the background image to "play"
            $("#bis_control").css({ "background-image": "url(/js/bgimg_slideshow/images/btn_play.png)" });
            // Clear the interval
            clearInterval(interval);
            started = false;
        };

        $.bgimgSlideshow.startSlideshow = function () {
            $("#bis_control").css({ "background-image": "url(/js/bgimg_slideshow/images/btn_pause.png)" });
            $.bgimgSlideshow.navigate("next");
            interval = setInterval(function () { $.bgimgSlideshow.navigate("next"); }, options.slideshowSpeed);
            started = true;
        };

        $.bgimgSlideshow.initialize();
        return this;
    }

})(jQuery);