/* 
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

var TimeToFade = 750.0;

function fade(eid) {
    var element = document.getElementById(eid);
    if(element == null)
        return;

    if(element.FadeState == null) {
        if(element.style.opacity == null
            || element.style.opacity == ''
            || element.style.opacity == '1') {
            element.FadeState = -2;
        } else {
            element.FadeState = 2;
        }
    }

    if(element.FadeState == 1 || element.FadeState == -1) {
        element.FadeState = element.FadeState == 1 ? -1 : 1;
        element.FadeTimeLeft = TimeToFade - element.FadeTimeLeft;
    } else {
        element.FadeState = element.FadeState == 2 ? -1 : 1;
        element.FadeTimeLeft = TimeToFade;
        setTimeout("animateFade(" + new Date().getTime() + ",'" + eid + "')", 33);
    }
}

function animateFade(lastTick, eid) {
    var curTick = new Date().getTime();
    var elapsedTicks = curTick - lastTick;

    var element = document.getElementById(eid);

    if(element.FadeTimeLeft <= elapsedTicks) {
        element.style.opacity = element.FadeState == 1 ? '1' : '0';
        element.style.filter = 'alpha(opacity = ' + (element.FadeState == 1 ? '100' : '0') + ')';
        element.FadeState = element.FadeState == 1 ? 2 : -2;
        return;
    }

    element.FadeTimeLeft -= elapsedTicks;
    var newOpVal = element.FadeTimeLeft/TimeToFade;
    if(element.FadeState == 1)
        newOpVal = 1 - newOpVal;

    element.style.opacity = newOpVal;
    element.style.filter =  'alpha(opacity = ' + (newOpVal*100) + ')';

    setTimeout("animateFade(" + curTick + ",'" + eid + "')", 33);
}