// -----------------------------------------------------------------------------------
// 
// This page coded by Scott Upton
// http://www.uptonic.com | http://www.couloir.org
//
// This work is licensed under a Creative Commons License
// Attribution-ShareAlike 2.0
// http://creativecommons.org/licenses/by-sa/2.0/
//
// Associated API copyright 2002, Travis Beckham (www.squidfingers.com)
//
// -----------------------------------------------------------------------------------
// --- version date: 04/30/05 ------------------------------------------------------

var photoDir = "images/"; // Location of photos for gallery
var borderSize = 6;	 // = 2x CSS border size

// get current photo id from URL
var thisURL = document.location.href;
var splitURL = thisURL.split("#");
var photoId = splitURL[1] - 1;

// if no id in query string then set to 0
photoId = (!photoId)? 0:photoId;
	
// Define each photo's name, height, width, and caption
var photoArray = new Array(
	// Source, Width, Height, Caption

new Array("../images/students_out.jpg", "800", "400", "Student's cafeteria - Students having a break at the cafeteria"),
new Array("../images/library_gala1.jpg", "800", "400", "IU Library - A peaceful studying environment"),             
new Array("../images/receive_mase.jpg", "800", "400", "IU launch - The chancellor receiving the mace"),
new Array("../images/kiserian_plan.jpg", "800", "400", "Main campus - The model plan of the Kiserian IU campus"),
new Array("../images/arc_explain_plan.jpg", "800", "400", "Main campus site visit - ARC explains the model plan of the Kiserian IU campus"),
new Array("../images/iu_cake.jpg", "800", "400", "IU Cake - Come have it at IU"),
new Array("../images/ksps_staff.jpg", "800", "400", "IU Staff - The team at IU")
);

// Number of photos in this gallery
var photoNum = photoArray.length;

// Create access to 'Detect' object and a place to put instances of 'HTMLobj'
API = new Detect();

// CREATE INSTANCES & LOAD
loadAPI = function(){
	// Instantiate HTMLobj
	API.Container		= new HTMLobj('Container');
	API.Photo			= new HTMLobj('Photo');
	API.PhotoContainer	= new HTMLobj('PhotoContainer');
	API.LinkContainer	= new HTMLobj('LinkContainer');
	API.PrevLink		= new HTMLobj('PrevLink');
	API.NextLink		= new HTMLobj('NextLink');
	API.CaptionBlock	= new HTMLobj('CaptionBlock');
	API.Counter			= new HTMLobj('Counter');
	API.Caption			= new HTMLobj('Caption');
	API.LoadImg			= new HTMLobj('LoadImg');
	
	// Show initial photo
	cyclePhoto(photoId);
}
onload = loadAPI;

// Fade in photo when it is loaded from the server
initFade = function(){
	// Show PhotoContainer again
	API.PhotoContainer.show();
	
	// Be certain the tween is complete before fading, too
	var fade_timer = setInterval('startFade()', 1000);
					
	// Fade photo in when ready and clear listener
	startFade = function(){
		if(API.Container._tweenRunning == false){
			clearInterval(fade_timer);
			
			// Be certain fade is done running before allowing next/previous links to work
			// This avoids rapid fade-in when users click next/previous links in quick succession
			var adv_timer = setInterval('permitNextPrev()', 500);
			
			// Permit next/previous links to function normally when fade is completed
			permitNextPrev = function(){
				if(API.Photo._fadeRunning == false){
					clearInterval(adv_timer);
					
					// Only show links if there is more than one photo in array
					if(photoNum > 1){
						API.LinkContainer.displayShow();
						document.getElementById('NextLink').onclick = nextPhoto;
						document.getElementById('PrevLink').onclick = prevPhoto;
					}
				} else {
					return;
				}
			}
			// Swap out loading animation to spare CPU cycles when hidden anyway
			API.LoadImg.setSrc("images/slideshow/start.gif");
			
			// Show caption again
			API.CaptionBlock.show();
			
			// Fade photo in
			API.Photo.fadeIn(0,15,33);
		} else {
			return;
		}
	}
}

// Prevent next/previous
falsify = function(){
	return false;
}

// Go to next photo
nextPhoto = function(){
	// Go to next photo
	if(photoId == (photoArray.length - 1)){
		photoId = 0;
	} else {
		photoId++;
	}
	cyclePhoto(photoId);
}

// Go to previous photo
prevPhoto = function(){
	// If at start, go back to end
	if(photoId == 0){
		photoId = photoArray.length - 1;
	} else {
		photoId--;
	}
	cyclePhoto(photoId);
}

// Alter class of elements
changeElementClass = function(objId,setClass) {
	document.getElementById(objId).className = setClass;
}

// Function to load subsequent photos in gallery
cyclePhoto = function(photoId){
			
	// Swap in loading animation
	API.LoadImg.setSrc("images/slideshow/loading_ani2.gif");
	
	// Hide link container if it is not already hidden
	API.LinkContainer.displayHide();
	
	// Hide photo container and caption temporarily
	API.Photo.hide();
	API.Photo.setOpacity(0);
	API.CaptionBlock.hide();
	
	// Get dimensions of photo
	var wNew = photoArray[photoId][1];
	var hNew = photoArray[photoId][2];
	
	// Start tween on a delay
	var wCur = API.Container.getWidth() - borderSize;
	var hCur = API.Container.getHeight() - borderSize;
	
	// Begin tweening on a short timer
	setTimeout('API.Container.tweenTo(easeInQuad, ['+wCur+', '+hCur+'], ['+wNew+','+hNew+'], 7)',500);
	setTimeout('API.LinkContainer.sizeTo('+wNew+','+hNew+')',500);
	setTimeout('API.PrevLink.sizeTo('+wNew/2+','+hNew+')',500);
	setTimeout('API.NextLink.sizeTo('+wNew/2+','+hNew+')',500);
	setTimeout('API.CaptionBlock.sizeTo('+wNew+',18)',500);
	
	// Get new photo source
	var newPhoto = photoDir + photoArray[photoId][0];
	
	// Set source, width, and height of new photo
	API.Photo.setSrc(newPhoto);		
	API.Photo.sizeTo(wNew,hNew);
	
	// Set links to new targets based on photoId
	API.NextLink.setHref("#" + (photoId+1));
	API.PrevLink.setHref("#" + (photoId+1));
	API.Counter.setInnerHtml((photoId+1)+" of "+photoNum+" |");
	API.Caption.setInnerHtml(photoArray[photoId][3]);
	
	// Event listeners for onload and onclick events
	document.getElementById('Photo').onload = initFade;
	
	// Block next/previous links until permitNextPrev() has fired
	document.getElementById('NextLink').onclick = falsify;
	document.getElementById('PrevLink').onclick = falsify;
};