var timer; 
var current_location = 0;
var next_location = 1; 
var pics_loaded = 0;
var onoff = 0;
var direction = 1;
var timeout_value;
var images = new Array;
var photo_urls = new Array;
var transitionNames = new Array;
var transitions = new Array;
var current_transition = 0;
var loop = 1;
transitions[0] = "progid:DXImageTransform.Microsoft.Fade(duration=1)";
transitions[1] = "progid:DXImageTransform.Microsoft.Blinds(Duration=1,bands=20)";
transitions[2] = "progid:DXImageTransform.Microsoft.Checkerboard(Duration=1,squaresX=20,squaresY=20)";
transitions[3] = "progid:DXImageTransform.Microsoft.Strips(Duration=1,motion=rightdown)";
transitions[4] = "progid:DXImageTransform.Microsoft.Barn(Duration=1,orientation=vertical)";
transitions[5] = "progid:DXImageTransform.Microsoft.GradientWipe(duration=1)";
transitions[6] = "progid:DXImageTransform.Microsoft.Iris(Duration=1,motion=out)";
transitions[7] = "progid:DXImageTransform.Microsoft.Wheel(Duration=1,spokes=12)";
transitions[8] = "progid:DXImageTransform.Microsoft.Pixelate(maxSquare=10,duration=1)";
transitions[9] = "progid:DXImageTransform.Microsoft.RadialWipe(Duration=1,wipeStyle=clock)";
transitions[10] = "progid:DXImageTransform.Microsoft.RandomBars(Duration=1,orientation=vertical)";
transitions[11] = "progid:DXImageTransform.Microsoft.Slide(Duration=1,slideStyle=push)";
transitions[12] = "progid:DXImageTransform.Microsoft.RandomDissolve(Duration=1,orientation=vertical)";
transitions[13] = "progid:DXImageTransform.Microsoft.Spiral(Duration=1,gridSizeX=40,gridSizeY=40)";
transitions[14] = "progid:DXImageTransform.Microsoft.Stretch(Duration=1,stretchStyle=push)";
transitions[15] = "special case";
var transition_count = 15;


var slideShowLow = "http://imgdb.agitos.de/gallery/slideshow_low.php?set_albumName=uadby";

// Browser capabilities detection ---
// - assume only IE4+ and NAV6+ can do image resizing, others redirect to low 
if (is_ie4up || is_opera5up || is_nav6up) {
	//-- it's all good ---
} else {
	//-- any other browser we go low-tech ---
	document.location = slideShowLow;
}
// - IE5.5 and up can do the blending transition.
var browserCanBlend = (is_ie5_5up);

function stopOrStart() {
	if (onoff) {
		stop();
	} else {
		play();
	}
}

function stop() {
	onoff = 0;
	document.getElementById("startandstop").src = "images/play.gif";
	document.getElementById("startandstoplink").innerHTML = "Start Slideshow";
	clearTimeout(timer);
}

function play() {
	onoff = 1;
	if(document.getElementById("startandstop")) document.getElementById("startandstop").src = "images/stop.gif";
	if(document.getElementById("startandstoplink")) document.getElementById("startandstoplink").innerHTML = "Stop Slideshow";
	go_to_next_photo();
}

function playplain() {
	onoff = 1;
	go_to_next_photo();
}

function preload_complete() {
}

function reset_timer() {
	clearTimeout(timer);
	if (onoff) {
		timeout_value = 5000;
		timer = setTimeout('go_to_next_photo()', timeout_value);
	}
}

function wait_for_current_photo() {
	/* Show the current photo */
	if (!show_current_photo()) {
	/*
	 * The current photo isn't loaded yet.  Set a short timer just to wait
	 * until the current photo is loaded.
	 */
		clearTimeout(timer);
		timer = setTimeout('wait_for_current_photo()', 500);
		return 0;
	} else {
		preload_next_photo();
		reset_timer();
	}
}

function go_to_next_photo() {
	/* Go to the next location */
	current_location = next_location;
	/* Show the current photo */
	if (!show_current_photo()) {
		wait_for_current_photo();
		return 0;
	}
	preload_next_photo();
	reset_timer();
}

function go_to_following_photo() {
	/* Go to the next location */
	current_location = next_location;
	/* Show the current photo */
	if (!show_current_photo()) {
		wait_for_current_photo();
		return 0;
	}
	preload_next_photo();
	reset_timer();
}

function go_to_previous_photo() {
	/* Go to the next location */
	current_location = previous_location;
	/* Show the current photo */
	if (!show_current_photo()) {
		wait_for_current_photo();
		return 0;
	}
	preload_next_photo();
	reset_timer();
}

function preload_next_photo() {
	/* Calculate the new next location */
	next_location = (parseInt(current_location) + parseInt(direction));
	previous_location = (parseInt(current_location) - parseInt(direction));
	if (next_location > photo_count) {
		next_location = 1;
		if (!loop) {
			stop();
		}
	}
	if (next_location == 0) {
		next_location = photo_count;
		if (!loop) {
			stop();
		}
	}
	if (previous_location > photo_count) {
		previous_location = 1;
		if (!loop) {
			stop();
		}
	}
	if (previous_location == 0) {
		previous_location = photo_count;
		if (!loop) {
			stop();
		}
	}
	/* Preload the next photo */
	preload_photo(next_location);
	preload_photo(previous_location);
}

function show_current_photo() {
	/*
	* If the current photo is not completely loaded don't display it.
	*/
	if (!images[current_location] || !images[current_location].complete) {
		preload_photo(current_location);
		return 0;
	}
	/* transistion effects */
	if (browserCanBlend){
		var do_transition;
		if (current_transition == (transition_count)) {
			do_transition = Math.floor(Math.random() * transition_count);
		} else {
			do_transition = current_transition;
		}
		document.images.slide.style.filter=transitions[do_transition];
		document.images.slide.filters[0].Apply();
	}
	document.slide.src = images[current_location].src;
	document.getElementById("aid").value = (current_location - 1 ) * 2;
	if (browserCanBlend) {
		document.images.slide.filters[0].Play();
	}
	return 1;
}

function preload_photo(index) {
	/* Load the next picture */
	if (pics_loaded < photo_count) {
		/* not all the pics are loaded.  Is the next one loaded? */
		if (!images[index]) {
			images[index] = new Image;
			images[index].onLoad = preload_complete();
			images[index].src = document.getElementById("photo_urls_" + index).href;
			pics_loaded++;
		}
	} 
}