var frameTotal; //total number of "frames" in a section
var currentFrame = 1; //currently displayed frame
var SCROLL_INCREMENT = 900;

//Change out the HTML for the main data section.
function changeHTML(newData, newFrameCount) {
	currentFrame = 1;
	
	if (newFrameCount)
		frameTotal = newFrameCount;
	else
		frameTotal = 1;
		
	$("#portfolio").load(newData, loadComplete);
}
function loadComplete(){
	$('#mainProject').scrollTo(0, 1);
	checkBtns();
}

//Check the state of the frames and set the buttons appropriately
function checkBtns(){
	if (frameTotal == 1){
		$("#btn_start, #btn_rewind, #btn_forward, #btn_end, #navInstru").css("visibility","hidden");
	}
	else if (currentFrame == 1){
		$("#btn_start, #btn_rewind").css("visibility","hidden");
		$("#btn_forward, #btn_end, #navInstru").css("visibility","visible");
	}
	else if (currentFrame > 1 && currentFrame < frameTotal){
		$("#btn_start, #btn_rewind, #btn_forward, #btn_end, #navInstru").css("visibility","visible");
	}
	else if (currentFrame == frameTotal){
		$("#btn_start, #btn_rewind, #navInstru").css("visibility","visible");
		$("#btn_forward, #btn_end").css("visibility","hidden");
	}
}

function scrollToFrame(frameNumber){
	var coordinate = (frameNumber-1) * SCROLL_INCREMENT;
	$('#mainProject').scrollTo( coordinate+'px' );
	currentFrame = frameNumber;
	checkBtns();
}

//Once the doc is loaded fully
$(document).ready(function() {

	scrollToFrame(1);
	
	
	//Main menu hover	
	var hoverConfig = {    
		sensitivity: 3, // number = sensitivity threshold (must be 1 or higher)  	     
		interval: 200, // number = milliseconds for onMouseOver polling interval     
		over: function(){$(this).children('ul.menu').slideDown();},
		timeout: 100, // number = milliseconds delay before onMouseOut    
		out: function(){$(this).children('ul.menu').slideUp();}
	};
	$("div.menuItem").hoverIntent(hoverConfig);


	//Set the nav button behavior
	$.scrollTo.defaults.axis = "x";
	$.scrollTo.defaults.onAfter = checkBtns; 
	$.scrollTo.defaults.easing = "easeInOutQuad"; 
	$.scrollTo.defaults.duration = 1000; 
	
	$("#btn_start").click(function(){
		$('#mainProject').scrollTo(0);
		currentFrame = 1;
		checkBtns();
	});
	
	$("#btn_rewind").click(function(){
		$('#mainProject').scrollTo( '-='+SCROLL_INCREMENT+'px' );
		currentFrame--;
		checkBtns();
	});
	
	$("#btn_forward").click(function(){
		$('#mainProject').scrollTo( '+='+SCROLL_INCREMENT+'px' );
		currentFrame++;
		checkBtns();
	});
	
	$("#btn_end").click(function(){
		$('#mainProject').scrollTo(SCROLL_INCREMENT*(frameTotal-1));
		currentFrame = frameTotal;
		checkBtns();
	});
	
});