/**
 * author Malena Andrade 
 * url http://www.mandrade.com
 */


var barrelSpeed = .4;
var storySpeed;

var $window = $(window);

var $container;
var $barrels;
var $story;

var barrelsHeight;
var storyHeight;
var homeHeight;
	
var yr12;
var yr11;
var yr10;
var yr9;
var yr8;
var yr7;
var yr6;
var yr5;
var yr4;
var yr3;
var yr2;
var yr1;

function adjustClock(){

	// story scroll  is the number of pixels that scroll into the viewing area (window)

	var storyScroll = $window.height() - $story.offset().top + $window.scrollTop() - 300;

	if (storyScroll > yr1)
	{
		$("#clock").css("background-position", "0 -2880px" );
	}
	else if (storyScroll > yr2)
	{
		$("#clock").css("background-position", "0 -2640px" );
	}
	else if (storyScroll > yr3)
	{
		$("#clock").css("background-position", "0 -2400px" );
	}
	else if (storyScroll > yr4)
	{
		$("#clock").css("background-position", "0 -2160px" );
	}
	else if (storyScroll > yr5)
	{
		$("#clock").css("background-position", "0 -1920px" );
	}
	else if (storyScroll > yr6)
	{
		$("#clock").css("background-position", "0 -1680px" );
	}
	else if (storyScroll > yr7)
	{
		$("#clock").css("background-position", "0 -1440px" );
	}
	else if (storyScroll > yr8)
	{
		$("#clock").css("background-position", "0 -1200px" );
	}
	else if (storyScroll > yr9)
	{
		$("#clock").css("background-position", "0 -960px" );
	}
	else if (storyScroll > yr10)
	{
		$("#clock").css("background-position", "0 -720px" );
	}
	else if (storyScroll > yr11)
	{
		$("#clock").css("background-position", "0 -480px" );
	}
	else if (storyScroll > yr12)
	{
		$("#clock").css("background-position", "0 -240px" );
	}
	else
	{
		$("#clock").css("background-position", "0 0px" );
	}
}

function setStorySpeed(){
	var storyDisplacement = storyHeight - $window.height() + homeHeight;
	var barrelsDisplacement = barrelsHeight - $window.height();

	// Barrel Movement --> 1 : 1 + barrelSpeed
	// Story Movement --> 1 : 1 + barrelSpeed + storySpeed

	storySpeed = ((storyDisplacement / barrelsDisplacement) * (1 + barrelSpeed)) - 1 - barrelSpeed;
	storySpeed = storySpeed * 1.15;
}

function resizeContainer() {
	var originalDisplacement = barrelsHeight - $window.height(); 
	var displacement = originalDisplacement / (1 + barrelSpeed);
	var containerHeight = $window.height() + displacement;

	$container.css("height", containerHeight + "px");
}

function parallax() {
	var scrollTop = $window.scrollTop();

	//barrels top position is moving up 
	$barrels.css("top", "-" + (scrollTop * barrelSpeed) + "px");
	
	// story top position is moving up
	$story.css("top", "-" + (scrollTop * storySpeed) + "px");

	adjustClock();
}

$window.resize(function() {
	resizeContainer();
	setStorySpeed();
	parallax();
});

$window.scroll(parallax);

$(document).ready(function() {
	$container = $("#container");
	$barrels = $("#barrels");
	$story = $("#story");

	barrelsHeight = $barrels.height();
	storyHeight = $story.height();
	homeHeight = $("#home").height();

	resizeContainer();
	setStorySpeed();
	adjustClock();
	
	yr12 = Math.ceil($("#year12").position().top); 
	yr11 = Math.ceil($("#year11").position().top); 
	yr10 = Math.ceil($("#year10").position().top); 
	yr9 = Math.ceil($("#year9").position().top); 
	yr8 = Math.ceil($("#year8").position().top); 
	yr7 = Math.ceil($("#year7").position().top); 
	yr6 = Math.ceil($("#year6").position().top); 
	yr5 = Math.ceil($("#year5").position().top); 
	yr4 = Math.ceil($("#year4").position().top); 
	yr3 = Math.ceil($("#year3").position().top); 
	yr2 = Math.ceil($("#year2").position().top); 
	yr1 = Math.ceil($("#year1").position().top); 

});