/* JavaScript Library file for estimator functions. */

/* Begin common functions. */
// initialize this UA variable.
var blnUseTextarea = true;		// default to True

function validate_required(field)
{
if (field==null||field=="")
  {return false}
else {return true}
}

// Removes Commas and any other characters which are not numbers 
function RemoveCommas(value)
{
	var temp2 = "";
    	var Done = false;
    	var Max = value.length-1;
    	for (var i=0; i<=Max; i++)
      	{
          	if ((" 0".indexOf(value.charAt(i))==-1)||Done) 
            	{  
              		if("0123456789.-".indexOf(value.charAt(i))!=-1)
				{
					temp2 = temp2 + value.charAt(i);
				}
             		Done=true;
            	}
        	}
    	value = temp2;
    	return value;
}

// Check for numeric values only, allow one decimal point (.) and multiple commas (,).
function CharAlert(value)
{
	var i = value.indexOf(".");
	if (i!=-1) if (value.indexOf(".",i+1)!=-1) return false;
	for (i=0; i<=value.length-1; i++)  if("0123456789.,".indexOf(value.charAt(i))==-1) return false;
	// It's Good
	return true;
}

// Check for numeric values only, allow one decimal point (.).  Do not allow commas (,).
function CommaAlert(value)
{
	var i = value.indexOf(".");
	if (i!=-1) if (value.indexOf(".",i+1)!=-1) return false;
	for (i=0; i<=value.length-1; i++)  if("0123456789.".indexOf(value.charAt(i))==-1) return false;
	// It's Good
	return true;
}

// Verify value is a Real number.  Allow one decimal point (.).  Allow one negative sign (-) only at beginning.  Do not allow commas (,).
function RealNumber(value)
{
	var d = value.indexOf(".");
	if (d!=-1) if (value.indexOf(".",d+1)!=-1) return false;	// don't allow multiple decimal points
	var m = value.indexOf("-");
	if (m!=-1) if (value.indexOf("-",1)!=-1) return false;	// don't allow any negative signs that are not at the beginning
	for (i=0; i<=value.length-1; i++)  if("0123456789.-".indexOf(value.charAt(i))==-1) return false;		// contains a non-numeric character
	// It's Good
	return true;
}
// Converts numbers in to currency number (adds decimal point)
function FormatCurrency(amount)
{
      var temp = "" + Math.round(100*amount);
      while (temp.length <= 2) temp = "0" + temp;
      var DecPlace = temp.length-2; 
      return temp.substring(0,DecPlace) + "." + temp.substring(DecPlace, temp.length);
}

// Formats numbers with commas every 3 digits to left of decimal point
function AddCommas(amount)
{
      var DecPlace = amount.indexOf(".");
      if (DecPlace >= 0) {  // has a decimal
      	var LeftOfDecimal = amount.substring(0, (DecPlace));
      }
      else {
      	var LeftOfDecimal = amount;
      }
      var temp = LeftOfDecimal;
      var i = 0;
      var array = new Array;
      while (temp.length > 3) {
      	array[i] = temp.substring(temp.length-3);  // rightmost 3 digits
      	temp = temp.substring(0,(temp.length-3));	// all digits to left of last 3 digits
      	i++;
      }
      if (temp.length <= 3) { // leftmost 3 digits
      	array[i] = temp;
      }
      var CommaFormatted = array[i];
      while (i > 0) {
      	i--;
      	CommaFormatted = CommaFormatted + "," + array[i];
      }
      if (DecPlace >= 0) {  // has a decimal
      	CommaFormatted = CommaFormatted + amount.substring(DecPlace,amount.length);	// append decimals
      }
      return CommaFormatted;
}

// Display appropriate error message and place cursor in offending field.
function HasError(field, form, txtErrorMessage) {
	if (blnUseTextarea) {		// attributes for <textarea> method
		var iHeight = Math.round(((txtErrorMessage.length)/60) + .5)*16;
		document.getElementById('display_error_message').style.height = iHeight + 'px';
	}
	form.display_error_message.size = txtErrorMessage.length ;		// attribute for <input> method
	document.getElementById('display_error_message').style.visibility = 'visible';
	form.display_error_message.value = txtErrorMessage;
	field.focus();
	field.select();
}

// Clear the error message and hide the message display element.
function ResetErrorMessageDisplay(form) {
	form.display_error_message.value = "";
	document.getElementById('display_error_message').style.visibility = 'hidden';
	document.getElementById('display_error_message').style.height = '0px';	// attribute for <textarea> method
}
/* End common functions. */

/* Begin Repay Loan Estimator functions. */
// initialize error message variables
var txtErrorNullLoanAmount = "";
var txtErrorInvalidLoanAmount = "";
var txtErrorNullInterestRate = "";
var txtErrorInvalidInterestRate = "";
var txtErrorNullTerm = "";
var txtErrorInvalidTerm = "";
var txtErrorZeroTerm = "";

function ValidateLRE(passForm)
{
	var txtLoan_Amount = "";
	var txtInterest_Rate = "";
	var txtNumber_of_Months_Years = "";
  
	txtLoan_Amount = passForm.loan_amount.value;
	txtInterest_Rate = passForm.interest_rate.value
	txtNumber_of_Months_Years = passForm.number_of_months_years.value

  if (!validate_required(txtLoan_Amount)) {
		HasError(passForm.loan_amount, document.repay_calc, txtErrorNullLoanAmount);
		return false;
	}
  else if (!CharAlert(txtLoan_Amount)) {
		HasError(passForm.loan_amount, document.repay_calc, txtErrorInvalidLoanAmount);
		return false;
	}
  else if (!validate_required(txtInterest_Rate)) {
		HasError(passForm.interest_rate, document.repay_calc, txtErrorNullInterestRate);
  		return false;
    }
  else if (!CommaAlert(txtInterest_Rate)) {
		HasError(passForm.interest_rate, document.repay_calc, txtErrorInvalidInterestRate);
		return false;
	}
  else if (passForm.number_of_months_years.value=="0") {
		HasError(passForm.number_of_months_years, document.repay_calc, txtErrorZeroTerm);
  		return false;
    }
  else if (!validate_required(txtNumber_of_Months_Years)) {
		HasError(passForm.number_of_months_years, document.repay_calc, txtErrorNullTerm);
  		return false;
  	}
  else if (!CommaAlert(txtNumber_of_Months_Years)) {
		HasError(passForm.number_of_months_years, document.repay_calc, txtErrorInvalidTerm);
		return false;
  	}
  else {
	ResetErrorMessageDisplay(document.repay_calc);
	for (i=0;i<passForm.month_year_param.length;i++) {
		if (passForm.month_year_param[i].checked==true) {
			switch (i) {
				case 0:
					txtNumber_of_Months_Years = passForm.number_of_months_years.value;
					break;
				case 1:
					txtNumber_of_Months_Years = Number(passForm.number_of_months_years.value) * 12;
		     		break;
				}
			break;
			}
		}
  	if (fnLoanRepayment(passForm,txtNumber_of_Months_Years,txtInterest_Rate,txtLoan_Amount)) {
  			return true;
  		}
  	}
}

function fnLoanRepayment(passForm,txtNumber_of_Months_Years,txtInterest_Rate,txtLoan_Amount)
{
	var Loan_Amount = RemoveCommas(txtLoan_Amount);
	var MonthlyPayment = Loan_Amount * fnPayment(txtInterest_Rate,txtNumber_of_Months_Years);
	var InterestCost = fnTotalInterest(MonthlyPayment, txtNumber_of_Months_Years, Loan_Amount);
	var MinimumSalary = fnMinSal(MonthlyPayment, .10);  // assume 10% of minimum salary
	var CumPayment = Number(Loan_Amount) + Number(InterestCost);
  
	document.repay_calc.monthly_payment.value = "$" + AddCommas(FormatCurrency(MonthlyPayment));
	document.repay_calc.interest_cost.value = "$" + AddCommas(FormatCurrency(InterestCost));
	document.repay_calc.minimum_salary.value = "$" + AddCommas(FormatCurrency(MinimumSalary));
	document.repay_calc.cum_payment.value = "$" + AddCommas(FormatCurrency(CumPayment));
return true;
}
		

// Calculates Payments with Interest and divides it in to months
function fnPayment(Rate, Months) 
{
	if (Rate != 0)
		{
			var a           // Monthly repayment rate
  		= Rate / 100. / 12.;
			var b = 1. + a;
    	b = Math.pow(b, Months) - 1.;
			var c = a / b + a;        // Monthly repayment factor
		}
	else
		{
			c= 1/Months; // If rate = 0 no interest charged
  	}
	return c;
}

// Calculates the total amount of Interest
function fnTotalInterest(Monthly , NofMonths , OriginalAmount)
{
	var a = Monthly * NofMonths;
	var b = a - OriginalAmount;
	return b;
}

// Calculates the minimum salary needed to handle the payments
function fnMinSal(Monthly , Percentage)
{
	var a = Monthly / Percentage;
	var b = a * 12;
	return b;
}
/* End Repay Loan Estimator functions. */

/* Begin Tuition College Cost Projector functions. */
// initialize error message variables
var txtErrorNullCurrentCost = "";
var txtErrorNullInflateRate = "";
var txtErrorNullYears_to_Enrollment = "";
var txtErrorInvalidCurrentCost = "";
var txtErrorInvalidInflateRate = "";
var txtErrorInvalidYears_to_Enrollment = "";	

function ValidateTCP(passForm, txtCurrent_Cost, txtCost_Inflate_Rate, txtYears_to_Enrollment) {
  // Clear error message display before starting.
  ResetErrorMessageDisplay(document.cost_projector);

  if (!validate_required(txtCurrent_Cost)) {
		HasError(passForm.current_cost, document.cost_projector, txtErrorNullCurrentCost);
		return false;
	}
  else if (!CharAlert(txtCurrent_Cost)) {
		HasError(passForm.current_cost, document.cost_projector, txtErrorInvalidCurrentCost);
		return false;
	}
  else if (!validate_required(txtCost_Inflate_Rate)) {
		HasError(passForm.cost_inflate_rate, document.cost_projector, txtErrorNullInflateRate);
  		return false;
    }
  else if (!CommaAlert(txtCost_Inflate_Rate)) {
		HasError(passForm.cost_inflate_rate, document.cost_projector, txtErrorInvalidInflateRate);
		return false;
	}
  else if (!validate_required(txtYears_to_Enrollment)) {
		HasError(passForm.years_to_enrollment, document.cost_projector, txtErrorNullYears_to_Enrollment);
  		return false;
  	}
  else if (!RealNumber(txtYears_to_Enrollment)) {
		HasError(passForm.years_to_enrollment, document.cost_projector, txtErrorInvalidYears_to_Enrollment);
  		return false;
  	}
  else return true;
}

function ProjectTuitionCost(passForm) {
	var txtCollege_Type = "";
	var iYears_in_College = 0;
	for (i=0;i<passForm.college_type.length;i++){
	    if (passForm.college_type[i].checked==true){
		switch (i) {
		    case 0:
		        txtCollege_Type="4 Year";
		        iYears_in_College = 4;
		        break;
		    case 1:
		        txtCollege_Type="2 Year";
		        iYears_in_College = 2;
		        break;
		}
		break //exist for loop, as target acquired.
	    }
	}
	var txtCurrent_Cost = passForm.current_cost.value;
	var txtCost_Inflate_Rate = passForm.cost_inflate_rate.value;
	var txtYears_to_Enrollment = passForm.years_to_enrollment.value;
	var blnContinue_Adjustments = new Boolean(true);
	for (i=0;i<passForm.continue_adjustments.length;i++){
	    if (passForm.continue_adjustments[i].checked==true){
		switch (i) {
		    case 0:
		        blnContinue_Adjustments = true;
		        break;
		    case 1:
		        blnContinue_Adjustments = false;
		        break;
		}
		break //exist for loop, as target acquired.
	    }
	}
	
	if (!ValidateTCP(passForm, txtCurrent_Cost, txtCost_Inflate_Rate, txtYears_to_Enrollment)) {
		return false;
	}
	
//	document.cost_projection.college_type.value = txtCollege_Type;
//	document.cost_projection.current_cost.value = "$" + FormatCurrency(RemoveCommas(txtCurrent_Cost));
//	document.cost_projection.cost_inflate_rate.value = txtCost_Inflate_Rate + "%";
//	document.cost_projection.years_to_enrollment.value = txtYears_to_Enrollment + strTemp;
//	document.cost_projection.continue_adjustments.value = blnContinue_Adjustments;
	
	var fltCost_Inflate_Rate = Number(txtCost_Inflate_Rate) * 0.01;
	var fltCompoundFactor = fltCost_Inflate_Rate + 1;
	
	var fltProjectedCost = Number(RemoveCommas(txtCurrent_Cost));  // set initial value.
	var iYears_to_Enrollment = Number(txtYears_to_Enrollment);
	var iYear2 = iYears_to_Enrollment + 1.0;
	var iYear3 = iYears_to_Enrollment + 2.0;
	var iYear4 = iYears_to_Enrollment + 3.0;
	var iYears_to_Graduation = iYears_to_Enrollment + (iYears_in_College - 1);
	var i = 1;

	// Calculate projected cost for each year.
	var fltProjectedCostYear1 = 0;
	var fltProjectedCostYear2 = 0;
	var fltProjectedCostYear3 = 0;
	var fltProjectedCostYear4 = 0;
	fltProjectedCostYear1 = fltProjectedCost*Math.pow(fltCompoundFactor,iYears_to_Enrollment);
     if (blnContinue_Adjustments) fltProjectedCostYear2 = fltProjectedCost*Math.pow(fltCompoundFactor,iYear2);
     else fltProjectedCostYear2 = fltProjectedCostYear1;
     if (blnContinue_Adjustments) fltProjectedCostYear3 = fltProjectedCost*Math.pow(fltCompoundFactor,iYear3);
     else fltProjectedCostYear3 = fltProjectedCostYear1;
     if (blnContinue_Adjustments) fltProjectedCostYear4 = fltProjectedCost*Math.pow(fltCompoundFactor,iYear4);
     else fltProjectedCostYear4 = fltProjectedCostYear1;
	
	var fltTotal_Projected_Cost = 0;
	if (txtCollege_Type=="2 Year") {
		fltTotal_Projected_Cost = fltProjectedCostYear1 + fltProjectedCostYear2;
		document.getElementById('thirdyear').style.visibility = 'hidden';
		document.getElementById('thirdyear').style.height = '0px';
		document.getElementById('fourthyear').style.visibility = 'hidden';
		document.getElementById('fourthyear').style.height = '0px';
	}
	else {
		fltTotal_Projected_Cost = fltProjectedCostYear1 + fltProjectedCostYear2 + fltProjectedCostYear3 + fltProjectedCostYear4;
		document.getElementById('thirdyear').style.visibility = 'visible';
		document.getElementById('thirdyear').style.height = 'auto';
		document.getElementById('fourthyear').style.visibility = 'visible';
		document.getElementById('fourthyear').style.height = 'auto';
	}
	document.cost_projection.Projected_Cost_Year_1.value = "$" + AddCommas(FormatCurrency(fltProjectedCostYear1));
	document.cost_projection.Projected_Cost_Year_2.value = "$" + AddCommas(FormatCurrency(fltProjectedCostYear2));
	document.cost_projection.Projected_Cost_Year_3.value = "$" + AddCommas(FormatCurrency(fltProjectedCostYear3));
	document.cost_projection.Projected_Cost_Year_4.value = "$" + AddCommas(FormatCurrency(fltProjectedCostYear4));
	document.cost_projection.Total_Projected_Cost.value = "$" + AddCommas(FormatCurrency(fltTotal_Projected_Cost));
	
	return true;
}
/* End Tuition College Cost Projector functions. */