/*
Thanks to http://brainerror.net/scripts/javascript/blendtrans/ for this script
*/

var followurl = 'http://www.printing-mailing.com/'
var trans_timer; 
var demo_timer; 
var trans_running = 0;

function opacity(id, opacStart, opacEnd, millisec) {
	//speed for each frame
	var speed = Math.round(millisec / 100);
	var timer = 0;

	//determine the direction for the blending, if start and end are the same nothing happens
	if(opacStart > opacEnd) {
		for(i = opacStart; i >= opacEnd; i--) {
			setTimeout("changeOpac(" + i + ",'" + id + "')",(timer * speed));
			timer++;
		}
	} else if(opacStart < opacEnd) {
		for(i = opacStart; i <= opacEnd; i++)
			{
			setTimeout("changeOpac(" + i + ",'" + id + "')",(timer * speed));
			timer++;
		}
	}
}

//change the opacity for different browsers
function changeOpac(opacity, id) {
	var object = document.getElementById(id).style; 
	object.opacity = (opacity / 100);
	object.MozOpacity = (opacity / 100);
	object.KhtmlOpacity = (opacity / 100);
	object.filter = "alpha(opacity=" + opacity + ")";
}

function shiftOpacity(id, millisec) {
	//if an element is invisible, make it visible, else make it ivisible
	if(document.getElementById(id).style.opacity == 0) {
		opacity(id, 0, 100, millisec);
	} else {
		opacity(id, 100, 0, millisec);
	}
}

function blendlink(imagefile, linkurl) {
	// kill demo on first rollover
	clearInterval(demo_timer);
	
	// make pretty
	blendimage('blenddiv','blendimage',imagefile,750);
	
	// set url variable too
	followurl = linkurl;
}

function followlink() {
	window.location.replace(followurl);
}

function blendimage(divid, imageid, imagefile, millisec) {
	var speed = Math.round(millisec / 100);
	var timer = 0;

	// let's try ignoring transitions until the first is complete	
	if (trans_running == 0) {
	
		trans_running = 1;

		// clear running transition and clear partial image
		clearTimeout(trans_timer);
		changeOpac(100,imageid);

		//set the current image as background
		document.getElementById(divid).style.backgroundImage = "url(" + document.getElementById(imageid).src + ")";
		
		//make image transparent
		changeOpac(0, imageid);
		
		//make new image
		document.getElementById(imageid).src = imagefile;

		//fade in image
		for(i = 0; i <= 100; i++) {
			trans_timer = setTimeout("changeOpac(" + i + ",'" + imageid + "')",(timer * speed));
			timer++;
			timer++;
		}

		//set final timer to reset flag
		setTimeout("trans_running = 0",timer * speed);

	}
}

function currentOpac(id, opacEnd, millisec) {
	//standard opacity is 100
	var currentOpac = 100;
	
	//if the element has an opacity set, get it
	if(document.getElementById(id).style.opacity < 100) {
		currentOpac = document.getElementById(id).style.opacity * 100;
	}

	//call for the function that changes the opacity
	opacity(id, currentOpac, opacEnd, millisec)
}

// last thing start timed demo transitions
demo_timer = setInterval("blendimage('blenddiv','blendimage','images/photo-2.jpg',750)",5000);
demo_timer = setInterval("blendimage('blenddiv','blendimage','images/photo-3.jpg',750)",10000);
demo_timer = setInterval("blendimage('blenddiv','blendimage','images/photo-4.jpg',750)",15000);
demo_timer = setInterval("blendimage('blenddiv','blendimage','images/photo-1.jpg',750)",20000);