/**
* =========================================================
* jquery.innerfade.js
* =========================================================
*
* Date: 2008-12-22
* Author: Fabian Neumann
* Web: http://www.fabianneumann.de/
* Web: http://www.sturzbach.de/
*
* Based on the works of:
* - Medienfreunde Hofmann & Baldes GbR, Torsten Baldes, http://medienfreunde.com
* - Matt Oakes, http://portfolio.gizone.co.uk/applications/slideshow/
* - Ralf S. Engelschall, http://trainofthoughts.org/
*
* Example:
*
*  <ul id="news">
*      <li>content 1</li>
*      <li>content 2</li>
*      <li>content 3</li>
*  </ul>
*
*  $('#news').innerfade({
*      animationtype: Type of animation 'fade' or 'slide' (Default: 'fade'),
*      speed: Fading-/Sliding-Speed in milliseconds or keywords (slow, normal or fast) (Default: 'normal'),
*      timeout: Time between the fades in milliseconds (Default: '2000'),
*      containerheight: Height of the containing element in any css-height-value (Default: 'auto'),
*      runningclass: CSS-Class which the container get’s applied (Default: 'innerfade'),
*      next_selector: jQuery selector of element(s) that let's you manually click forward (Default: '#if-next'),
*      prev_selector: jQuery selector of element(s) that let's you manually click backwards (Default: '#if-prev'),
*      pause_selector: optional jQuery selector of element(s) that on hover will pause the slideshow,
*      callback: optional function to call after each transition,
*      children: optional children selector (Default: null),
*  });
*
**/


(function($) {

    $.fn.innerfade = function(options) {
        return this.each(function() {
            $.innerfade(this, options);
        });
    };

    $.innerfade = function(container, options) {
        var settings = {
            'container': container, // container's data is used as state memory
            'animationtype': 'fade',
            'type': 'sequence',
            'speed': 'normal',
            'timeout': 2000,
            'containerheight': 'auto',
            'runningclass': 'innerfade',
            'children': null,
            'next_selector': '#if-next',
            'prev_selector': '#if-prev',
            'pause_selector': null,
            'callback': null
        };
        $.data(settings.container, 'paused', false);
        if (options)
            $.extend(settings, options);

        if (settings.children === null)
            var elements = $(container).children();
        else
            var elements = $(container).children(settings.children);

        if (elements.length < 1) return;

        if (settings.type == "sequence") {
            $.data(settings.container, 'current', 1);
            $.data(settings.container, 'last', 0);
        }

        if (settings.pause_selector !== null) {
            $(settings.pause_selector).hover(function() {
                $.data(settings.container, 'paused', true);
            }, function() {
                $.data(settings.container, 'paused', false);
            });
        }

        $(settings.prev_selector).click(function(e) {
            e.preventDefault();
            current = $.data(settings.container, 'current') - 2;
            if (current < 0) current = elements.length + current; // js modulo for negative numbers is strange (in IE)
            $.data(settings.container, 'current', current);
            $.innerfade.animate(elements, settings);
        });

        $(settings.next_selector).click(function(e) {
            e.preventDefault();
            $.innerfade.animate(elements, settings);
        });

        $(container).css('position', 'relative').css('height', settings.containerheight).addClass(settings.runningclass);
        for (var i = 0; i < elements.length; i++) {
            $(elements[i]).css('z-index', String(elements.length - i)).css('position', 'absolute').hide();
        };
        if (elements.length > 1) {
            setTimeout(function() { $.innerfade.next(elements, settings); }, settings.timeout);
        }
        $(elements[0]).show();
    };

    $.innerfade.next = function(elements, settings) {
        if (!$.data(settings.container, 'paused')) {
            $.innerfade.animate(elements, settings);
        }
        setTimeout((function() {
            $.innerfade.next(elements, settings);
        }), settings.timeout);
    };

    $.innerfade.animate = function(elements, settings) {
        current = $.data(settings.container, 'current');
        last = $.data(settings.container, 'last');
        if (settings.animationtype == 'slide') {
            $(elements[last]).slideUp(settings.speed);
            $(elements[current]).slideDown(settings.speed);
        } else if (settings.animationtype == 'fade') {
            $(elements[last]).fadeOut(settings.speed);
            $(elements[current]).fadeIn(settings.speed, function() {
                removeFilter($(this)[0]);
            });
        } else {
            alert('Innerfade-animationtype must either be \'slide\' or \'fade\'');
        }

        if (typeof (settings.callback) == "function") {
            settings.callback(current, elements[current]);
        }

        $.data(settings.container, 'last', current);
        $.data(settings.container, 'current', (current + 1) % elements.length);
    };

})(jQuery);

// **** remove Opacity-Filter in ie ****
function removeFilter(element) {
    if (element.style.removeAttribute) {
        element.style.removeAttribute('filter');
    }
}