function round(value,precision)
{
	var exp = Math.pow(10,precision);
	
	return Math.round(value*exp)/exp;
}

function initialize()
{
}

var youngLimits = new Array();

function addLimit(years,sex,limit5,limit85,limit95)
{
	if(youngLimits[years]==undefined) youngLimits[years] = Array();
	
	youngLimits[years][sex] = Array(limit5,limit85,limit95);
}

//boys
addLimit( 5,0,13.4,16.7,17.7);
addLimit( 6,0,13.4,16.9,18.0);
addLimit( 7,0,13.6,17.3,18.5);
addLimit( 8,0,13.8,17.7,19.1);
addLimit( 9,0,14.0,18.3,19.8);
addLimit(10,0,14.3,18.9,20.7);
addLimit(11,0,14.7,19.6,21.6);
addLimit(12,0,15.1,20.5,22.6);
addLimit(13,0,15.7,21.4,23.7);
addLimit(14,0,16.3,22.4,24.7);
addLimit(15,0,16.8,23.2,25.7);
addLimit(16,0,17.3,24.0,26.5);
addLimit(17,0,17.7,24.7,27.2);
addLimit(18,0,18.1,25.3,27.8);
addLimit(19,0,18.2,25.6,28.1);
//girls
addLimit( 5,1,13.1,17.0,18.2);
addLimit( 6,1,13.1,17.2,18.6);
addLimit( 7,1,13.2,17.6,19.1);
addLimit( 8,1,13.4,18.1,19.8);
addLimit( 9,1,13.7,18.8,20.7);
addLimit(10,1,14.1,19.5,21.6);
addLimit(11,1,14.6,20.4,22.7);
addLimit(12,1,15.2,21.4,23.9);
addLimit(13,1,15.8,22.4,25.0);
addLimit(14,1,16.3,23.3,25.9);
addLimit(15,1,16.7,24.0,26.7);
addLimit(16,1,16.9,24.5,27.2);
addLimit(17,1,17.1,24.8,27.5);
addLimit(18,1,17.2,25.0,27.7);
addLimit(19,1,17.2,25.1,27.8);

function recalculate(field)
{
	var form = field.form;
	
	if(field.type=="text")
	{
		if(field.value.indexOf(',')>0)
			field.value = field.value.replace(',','.');

		var numberRegExp = new RegExp("^[0-9\.,]*$");		
		if(!numberRegExp.test(field.value))
			field.value = field.value.replace(/[^0-9\.,]*/ig,'');	
	
		//check for double decimal separator
		var firstSep = field.value.indexOf(".");
		var secondSep = firstSep>0?field.value.indexOf(".",firstSep+1):-1;
		if(firstSep>0 && secondSep>firstSep)
		{
			field.value = field.value.substring(0,secondSep);
		}
	
		if(field.value[field.value.length-1]=='.')
			return;
	}

	var resultDiv = document.getElementById("bmiResult");
	var resultWeightDiv = document.getElementById("bmiResultWeight");

	var bmiAge = parseInt(form.bmiAge.value);	
	if(form.bmiAge.value>=5 && form.bmiAge.value<=18)
	{
		document.getElementById("bmiChooseSexSelect").style.removeProperty("display");
		document.getElementById("bmiChooseSexLabel").style.removeProperty("display");
	}else {
				document.getElementById("bmiChooseSexSelect").style.display = "none";
				document.getElementById("bmiChooseSexLabel").style.display = "none";
			}

	if(!form.bmiAge.value || !form.bmiWeight.value || !form.bmiHeight.value)
	{
		resultDiv.innerHTML = "";
		resultWeightDiv.innerHTML = "";
		return;
	}
		
	var bmiWeight = parseFloat(form.bmiWeight.value);
	var bmiHeight = parseFloat(form.bmiHeight.value)/100;
	var bmiSex = form.bmiSex.value;
	
	var bmi = bmiWeight/(bmiHeight*bmiHeight);
	var bmiResult = 0;//-1 niedowaga, 0 - ok, 1 nadwaga, 2 - otyłość
	var weightMin;
	var weightMax;

	if(bmiWeight<10 || bmiWeight>900 ||	bmiHeight<0.5 || bmiHeight>3 ||	bmi<4 || bmi>99)
	{
		resultDiv.innerHTML = "";
		resultWeightDiv.innerHTML = "";
		return;
	}

	if(bmiAge>=5 && bmiAge<20)
	{
		weightMin = calculateWeightForBMI(youngLimits[bmiAge][bmiSex][0],bmiHeight); 
		weightMax = calculateWeightForBMI(youngLimits[bmiAge][bmiSex][1],bmiHeight);
		if(bmi < youngLimits[bmiAge][bmiSex][0]) bmiResult = -1; else
		if(bmi > youngLimits[bmiAge][bmiSex][2]) bmiResult = 2; else
		if(bmi > youngLimits[bmiAge][bmiSex][1]) bmiResult = 1; 
		
	}else 
	if(bmiAge<121)
	{
		weightMin = calculateWeightForBMI(18.5,bmiHeight);
		weightMax = calculateWeightForBMI(25,bmiHeight);
		
		if(bmi<18.5) bmiResult = -1; else
		if(bmi>30) bmiResult = 2; else
		if(bmi>25) bmiResult = 1;
	}


	if(bmiAge<5)
	{
		resultDiv.innerHTML = "Wyznaczone BMI to: <b>"+round(bmi,1)+"</b>.<br/><br/>Skala BMI nie nadaje się jednak do obliczeń dla tak małych dzieci, nie sugeruj się więc tą wartością przy określaniu, czy waga jest prawidłowa!";
		resultWeightDiv.innerHTML = "";
	}else 
	if(bmiAge<121)
	{
		resultDiv.innerHTML = "<big>Wyliczone BMI to: <b>"+round(bmi,1)+"</b></big><br/><br/>";
		
		switch(bmiResult) 
		{
			case -1:
				resultDiv.innerHTML += "<span style=\"color: red\">Niedowaga</span>";
				break;
			case 0:
				resultDiv.innerHTML += "<span style=\"color: green\">Waga prawidłowa</span>";
				break;
			case 1:
				resultDiv.innerHTML += "<span style=\"color: orange\">Nadwaga</span>";
				break;
			case 2:
				resultDiv.innerHTML += "<span style=\"color: red\">Otyłość</span>";
				break;				
		}		
				
		resultWeightDiv.innerHTML = "Prawidłowa waga dla <br/>wzrostu <b>"+round(bmiHeight*100,0)+"cm</b>: <br/><br/>od "+round(weightMin,0)+"kg do "+round(weightMax,0)+"kg";

	}else
	{
		resultDiv.innerHTML = "Limit wieku tego kalkulatora to 120 lat.";
		resultWeightDiv.innerHTML = "";
	}

}

function calculateWeightForBMI(bmi,height)
{
	return round(bmi*height*height,1);
}


function selectInput(field)
{
	addClass(field,"input_selected");
	
	for(var i = 0; i < document.forms.length; i++)	
		for(var j = 0; j < document.forms[i].elements.length; j++)
   	{
			var currentElement = document.forms[i].elements[j];
		
			if(currentElement == field)
				continue;
			
			removeClass(currentElement,"input_selected");
		}
}

function addClass(item, classname) 
{
    var obj = item
    if (typeof item=="string") {
        obj = document.getElementById(item)
    }
    obj.className += " " + classname
}

function removeClass(item, classname) 
{
    var obj = item
    if (typeof item=="string") {
        obj = document.getElementById(item)
    }
    var classes = ""+obj.className
    while (classes.indexOf(classname)>-1) {
        classes = classes.replace (classname, "")
    }
    obj.className = classes
}

Number.prototype.toMoney = function(decimals, decimalSeparator, thousandsSeparator)
{ 
   var n = this;
   c = isNaN(decimals) ? 2 : Math.abs(decimals);
   d = decimalSeparator || '.';
   t = (typeof thousandsSeparator === 'undefined') ? ' ' : thousandsSeparator;
   sign = (n < 0) ? '-' : '',

   i = parseInt(n = Math.abs(n).toFixed(c)) + '', 
   j = ((j = i.length) > 3) ? j % 3 : 0; 

   return sign + (j ? i.substr(0, j) + t : '') + i.substr(j).replace(/(\d{3})(?=\d)/g, "$1" + t) + (c ? d + Math.abs(n - i).toFixed(c).slice(2) : ''); 
}

String.prototype.startsWith = function (str)
{
    return this.indexOf(str) == 0;
};