/* protoload 0.1 beta by Andreas Kalsch
 * last change: 09.07.2007
 *
 * This simple piece of code automates the creating of Ajax loading symbols.
 * The loading symbol covers an HTML element with correct position and size - example:
 * $('myElement').startWaiting() and $('myElement').stopWaiting()
 */

Protoload = {
    // the script to wait this amount of msecs until it shows the loading element
    timeUntilShow: 250,

    // opacity of loading element
    opacity: 0.8,

    // Start waiting status - show loading element
    startWaiting: function(element, className, timeUntilShow) {
        if (typeof element == 'string')
            element = document.getElementById(element);
        if (className == undefined)
            className = 'waiting';
        if (timeUntilShow == undefined)
            timeUntilShow = Protoload.timeUntilShow;

        if (element.id == 'mainContent') className = 'creating'; //문제 생성 이미지로 교체

        element._waiting = true;
        if (!element._loading) {
            var e = document.createElement('div');
            (element.offsetParent || document.body).appendChild(element._loading = e);
            e.style.position = 'absolute';
            try { e.style.opacity = Protoload.opacity; } catch (e) { }
            try { e.style.MozOpacity = Protoload.opacity; } catch (e) { }
            try { e.style.filter = 'alpha(opacity=' + Math.round(Protoload.opacity * 100) + ')'; } catch (e) { }
            try { e.style.KhtmlOpacity = Protoload.opacity; } catch (e) { }

        }
        element._loading.className = className;
        window.setTimeout((function() {
            if (this._waiting) {
                var left = this.offsetLeft,
					top = this.offsetTop,
					width = this.offsetWidth,
					height = this.offsetHeight,
					l = this._loading;

                l.style.left = left + 'px';
                l.style.top = top + 'px';
                l.style.width = width + 'px';
                l.style.height = height + 'px';
                l.style.display = 'inline';
            }
        }).bind(element), timeUntilShow);
    },

    // Stop waiting status - hide loading element
    stopWaiting: function(element) {
        if (element._waiting) {
            element._waiting = false;
            element._loading.parentNode.removeChild(element._loading);
            element._loading = null;
        }
    } /*,
	
	_zIndex: 1000000*/
};

if (Prototype) {
	Element.addMethods(Protoload);
	Object.extend(Element, Protoload);
}
/* */