/*
SLIDE SHOW VARIABLES AND FUNCTIONS
*/

var interval = 2500; 
var random_display = 0; 
var imageDir = "images/slides/"; 
var imageNum = 0; 

/*
SLIDE SHOW IMAGES ARRAY
To add a new image to the array, save the image titled with the
lowest remaining two-digit number. Add a new line at the bottom
of the below code, identical to the previous line, but with the
new image title instead of the image title of the previous line.

Save the image in the slides folder within the images folder.
*/

imageArray = new Array(); 
imageArray[imageNum++] = new imageItem(imageDir + "01.jpg"); 
imageArray[imageNum++] = new imageItem(imageDir + "02.gif"); 
imageArray[imageNum++] = new imageItem(imageDir + "03.jpg");
imageArray[imageNum++] = new imageItem(imageDir + "04.gif"); 
imageArray[imageNum++] = new imageItem(imageDir + "05.jpg"); 
imageArray[imageNum++] = new imageItem(imageDir + "06.jpg");
imageArray[imageNum++] = new imageItem(imageDir + "07.gif"); 
imageArray[imageNum++] = new imageItem(imageDir + "08.jpg");
//end of array

var totalImages = imageArray.length; 

function imageItem(image_location) { 
	this.image_item = new Image(); 
	this.image_item.src = image_location; 
}
function get_ImageItemLocation(imageObj) { 
	return(imageObj.image_item.src) 
}

function randNum(x, y) { 
	var range = y - x + 1; 
	return Math.floor(Math.random() * range) + x; 
}

function getNextImage() { 
	if (random_display) { 
		imageNum = randNum(0, totalImages-1); 
	}
	else { 
		imageNum = (imageNum+1) % totalImages; 
	}
	var new_image = get_ImageItemLocation(imageArray[imageNum]); 
	return(new_image); 
}

function getPrevImage() { 
	imageNum = (imageNum-1) % totalImages; 
	var new_image = get_ImageItemLocation(imageArray[imageNum]); 
	return(new_image); 
}

function prevImage(place) { 
	var new_image = getPrevImage(); 
	document[place].src = new_image; 
}

function switchImage(place) { 
	var new_image = getNextImage(); 
	document[place].src = new_image; 
	var recur_call = "switchImage('"+place+"')"; 
	timerID = setTimeout(recur_call, interval); 
}