function pmt(interest, months, principal) {

    	base = interest + 1;

    	t = Math.pow(base, months);

    	result = principal * t * interest / (t - 1);

    	return result;

}



function getMonthlyRate(totalPrice, yearInterest, months) {

	TAX = 1.08;

	capital = (totalPrice * TAX) / months;	

	sumaFinantata = totalPrice * TAX;

	interest = yearInterest / 12;



	principal = sumaFinantata;

	pmtValue = pmt(interest, months, principal);    	

	monthlyInterest = ((pmtValue * months) - totalPrice * TAX) / months;

    	rataLunara = capital + monthlyInterest;



	return Math.round(rataLunara * 100) / 100;

}



function displayRates(totalPriceRon, euro) {

	ronYearInterest = 0.2555;

	euroYearInterest = 0.18225;

	months = new Array(12, 18, 24, 36, 48, 60);

	for (i=0; i < months.length; i++) {		

		rateRon = getMonthlyRate(totalPriceRon, ronYearInterest, months[i]);

		rateEuro = getMonthlyRate(totalPriceRon / euro, euroYearInterest, months[i]);

		document.getElementById('ron' + months[i]).innerHTML = rateRon;

		document.getElementById('eur' + months[i]).innerHTML = rateEuro;

	}	

}



function displayRONRate(price, months) {

        ronYearInterest = 0.2555;

        rate = getMonthlyRate(price, ronYearInterest, months);

	document.getElementById('ron-rate').innerHTML = rate;
}



function displayEURORate(price, months, euro) {

        euroYearInterest = 0.18225;

        rate = getMonthlyRate(price / euro, euroYearInterest, months);

	document.getElementById('euro-rate').innerHTML = rate;

}



function isDigit(num) {

	if (num.length > 1) {

		return false;

	}



	var string="1234567890";

	if (string.indexOf(num) != -1) {

		return true;

	}



	return false;

}



function isBlank(val){

	if(val==null){return true;}

	for(var i=0;i<val.length;i++) {

		if ((val.charAt(i)!=' ')&&(val.charAt(i)!="\t")&&(val.charAt(i)!="\n")&&(val.charAt(i)!="\r")){return false;}

		}

	return true;

}



function isInteger(val){

	if (isBlank(val)) {

		return false;

	}

	

	for(var i = 0; i < val.length; i++){

		if(!isDigit(val.charAt(i))) { 

			return false;

		}

	}

	return true;

}



function displayCnRate(totalPrice, months) {

	if (!isInteger(totalPrice)) {

		alert("Valoare introdusa in campul \"Valoare credit\" trebuie sa fie un numar intreg.");

	}



	TAX = 1.06;

	yearInterest = 0.33;

	capital = (totalPrice * TAX) / months;	

	sumaFinantata = totalPrice * TAX;

	interest = yearInterest / 12;



	principal = sumaFinantata;

	pmtValue = pmt(interest, months, principal);	

	monthlyInterest = ((pmtValue * months) - totalPrice * TAX) / months;

    	rataLunara = capital + monthlyInterest;



	document.getElementById("rate").innerHTML = Math.round(rataLunara * 100) / 100;

}