// +++++++++++ SETUP +++++++++++ 
// utilizes library file >>> jquery.js
// utilizes library file >>> setTarget.js

function centerImgs() {
	$('.photo').each(function() {
		var wMax = $(this).width();
		var hMax = $(this).height();
		
		$(this).css('background-image', 'none');

		$('img', this).each(function() {
			var w = $(this).width();
			var mLeft = - (w - wMax) / 2;
			$(this).css('margin-left', mLeft);
			
			var h = $(this).height();
			var mTop = - (h - hMax) / 2;
			$(this).css('margin-top', mTop);

			$(this).fadeIn(2500);
		})
	});
}

function setCalculatorDefaults() {
	// get form border color
//	formBorderColor = $("#age").css('border-left-color');

	// set height
	$("#form").each(function () {
		var h = $(this).height();
		$(this).css('height', h);
	});
}

function goBack() {
	$("#form").html(prevForm);
	
	return false; // prevents page from re-loading
}

function calculator() {
	var errorBorderColor = "#FF0000";
	var error = false;
	
	var age = $("#age").val();
	var resting = $("#resting").val();

	// check for positive numerical values
	if ( (typeof age != "number") && (age <= 0) ) {
		$("#age").css('border-color', errorBorderColor);
		error = true;
	} else { $("#age").css('border-color', formBorderColor); }
	if ( (typeof resting != "number") && (resting <= 0) ) {
		$("#resting").css('border-color', errorBorderColor);
		error = true;
	} else { $("#resting").css('border-color', formBorderColor); }
	if (error) { return false; }
		
	// reset form borders
	$("#form input").each(function () {
		if ($(this).id != "calculate") { $(this).css('border-color', formBorderColor); }
	});

	// calculate target heart rate range
	var reserve = 220 - age - resting;
	var targetLow = Math.round(reserve * .50) + parseInt(resting);
	var targetHigh = Math.round(reserve * .85) + parseInt(resting);
	var range = '';
	range = targetLow;
	range += ' - ';
	range += targetHigh;
	
	// set results innerHTML
	var results = '';
	results += '<p class="first">Your target heart rate range is:</p>';
	results += '<div id="target">';
	results += '<span id="target">' + range + '</span>';
	results += ' bpm</div>';
	results += '<form onsubmit="return goBack();">';
	results += '<input id="back" type="image" value="Go Back" src="http://www.ocbodybusiness.com/images/calculator.back.gif" />';
	results += '</form>';
	
	// remember form & show results
	prevForm = $("#form").html();
	$("#form").html(results);
	
	return false; // prevents page from re-loading
}

var formBorderColor = '#666666';
var prevForm;

//$(document).ready(function(){
$(window).load(function(){
	setCalculatorDefaults();
	setTarget('external', '_blank');
	centerImgs();
});