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

var activeForm = 1;

function initialize()
{
	document.chooseForm0.pizzaPrice.value = 35.50;
	document.chooseForm0.pizzaPieces.value = 1;	
	document.chooseForm0.pizzaDiscount.value = 0;	
	document.chooseForm0.pizzaType.value = 0;
	document.chooseForm0.pizzaSizeX.value=38;
	document.chooseForm0.pizzaSizeY.value=30;

	document.chooseForm1.pizzaPrice.value = 27;
	document.chooseForm1.pizzaPieces.value = 2;	
	document.chooseForm1.pizzaDiscount.value = 10;	
	document.chooseForm1.pizzaType.value=0;
	document.chooseForm1.pizzaSizeX.value=32;
	document.chooseForm1.pizzaSizeY.value=30;
	
	recalculate(document.chooseForm0.pizzaPrice,document.chooseForm0);
	recalculate(document.chooseForm1.pizzaPrice,document.chooseForm1);
}

function recalculate(field,form)
{
	var formNum = form.name.substring(form.name.length-1);

	if(field.id == "pizzaType")
	{
		if(form.pizzaType.value == 0)
		{
			document.getElementById("pizzaSizeXLabel"+formNum).innerHTML = "Średnica";
			document.getElementById("pizzaSizeYLabelDiv"+formNum).style.display = "none";
			document.getElementById("pizzaSizeYInputDiv"+formNum).style.display = "none";
		}
		if(form.pizzaType.value == 1)
		{
				document.getElementById("pizzaSizeXLabel"+formNum).innerHTML = "Rozmiar";
				document.getElementById("pizzaSizeYLabelDiv"+formNum).style.display = "none";
				document.getElementById("pizzaSizeYInputDiv"+formNum).style.display = "none";
		}
		if(form.pizzaType.value == 2)
		{
				document.getElementById("pizzaSizeXLabel"+formNum).innerHTML = "Długość";
				document.getElementById("pizzaSizeYLabelDiv"+formNum).style.removeProperty("display");
				document.getElementById("pizzaSizeYInputDiv"+formNum).style.removeProperty("display");
		}
	}

	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;
	}	
	
	if(!form.pizzaPrice.value || !form.pizzaSizeX.value || (form.pizzaType.value && !form.pizzaSizeY.value)) 
	{
		form.resultPricePerUnit.value = "";
		form.resultToPay.value = "";
		return;
	}

	if(form.pizzaDiscount.value>99.9)
		form.pizzaDiscount.value = 99.9;
	
	var pizzaPieces = 1;
	if(form.pizzaPieces.value) pizzaPieces = form.pizzaPieces.value;
	
	var pizzaDiscount = 0;
	if(form.pizzaDiscount.value) pizzaDiscount = form.pizzaDiscount.value;
	
	var pizzaArea;
	
	if(form.pizzaType.value == 0)
		pizzaArea = Math.PI * Math.pow(parseFloat(form.pizzaSizeX.value)/2, 2);
	else
	if(form.pizzaType.value == 1)
		pizzaArea = Math.pow(parseFloat(form.pizzaSizeX.value),2);
	else
	if(form.pizzaType.value == 2)
		pizzaArea = parseFloat(form.pizzaSizeX.value) * parseFloat(form.pizzaSizeY.value);
	
	var pizzaPrice = form.pizzaPrice.value * (1 - pizzaDiscount / 100);
	
	form.resultPricePerUnit.value = round((pizzaPrice / pizzaArea) * 100 * 100,0);
	form.resultToPay.value = (pizzaPrice * pizzaPieces).toMoney(2,'.',' ');
	form.resultArea.value = pizzaArea*pizzaPieces;
	
	var cheapest = -1;
	for(var i = 0; i<=activeForm; i++)
	{
		if(cheapest<0 && document.forms[i].resultPricePerUnit.value)
		{
			cheapest = i;
			continue;
		}
		
		if(!document.forms[i].resultPricePerUnit.value)
			continue;
			
		if(parseFloat(document.forms[i].resultPricePerUnit.value) < parseFloat(document.forms[cheapest].resultPricePerUnit.value))
			cheapest = i;
	}
	
	for(var i = 0; i<=activeForm; i++)
	{
		var info;
		var compareArea = round((parseFloat(document.forms[i].resultArea.value) - parseFloat(document.forms[cheapest].resultArea.value))/parseFloat(document.forms[cheapest].resultArea.value)*100,0);
		var compareToPay = round((parseFloat(document.forms[i].resultToPay.value) - parseFloat(document.forms[cheapest].resultToPay.value))/parseFloat(document.forms[cheapest].resultToPay.value)*100,0);
		
		if(Number.isNaN(compareArea) || Number.isNaN(compareToPay))
			info = "";
		else
		if(i == cheapest || (compareArea == compareToPay))
			info = "<b style=\"color: green\">Ta pizza jest najtańsza!</b>"
		else
		{
			if(compareToPay<0)
			{
				info = "Za tę zapłacisz "+ (-compareToPay) + "% mniej";
				if(compareArea<0)
					info += " i jest o "+ (-compareArea) + "% mniejsza";
			}
			else
			if(compareToPay==0)
			{
				info = "Za tę zapłacisz tyle samo";
				if(compareArea<0)
					info += ", ale jest o " + (-compareArea) +"% mniejsza";
			}
			else
			{
				info = "Za tę zapłacisz o "+compareToPay+"% więcej";
				if(compareArea<0)
					info += " i  jest o "+(-compareArea) + "% mniejsza";
				else
				if(compareArea==0)
					info += " a ma taki sam rozmiar.";
				else
					info += " a jest tylko o "+compareArea + "% większa";				
			}
		}
	
		document.getElementById("resultLabel"+i).innerHTML = info;
	}
}

function activateForm()
{    
    activeForm++;
	
	document.getElementById("comparable_view_"+activeForm).style.removeProperty("display");
	
	document.forms[activeForm].pizzaPrice.value = document.forms[activeForm-1].pizzaPrice.value;
	document.forms[activeForm].pizzaPieces.value = document.forms[activeForm-1].pizzaPieces.value;
	document.forms[activeForm].pizzaDiscount.value = document.forms[activeForm-1].pizzaDiscount.value;
	document.forms[activeForm].pizzaType.value = document.forms[activeForm-1].pizzaType.value;
	document.forms[activeForm].pizzaSizeX.value = document.forms[activeForm-1].pizzaSizeX.value;
	document.forms[activeForm].pizzaSizeY.value = document.forms[activeForm-1].pizzaSizeY.value;
	
	recalculate(document.forms[activeForm].pizzaPrice,document.forms[activeForm]);
	
	if(activeForm==document.forms.length-1)
	{		
		document.getElementById("comparable_view_activation").style.display = "none";
	}
	
	return false;
}

function selectInput(field)
{
	addClass(field,"input_selected");
	
	for(var i = 0; i < field.form.elements.length; i++)
   {
		var currentElement = field.form.elements[i];
		
		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) : ''); 
}