#include <iostream> 
#include <cmath> 
#include <iomanip> 

using namespace std; 





int main()
{
	//local variables
	float LOAN_AMOUNT=0; //loan amt
	float INT_RATE=0;	 //interest rate
	int TERM_YEARS=0;	 //loan term in years
	char quit;			 //determines if user wants to quit
	
	
	do
	{
		
        //output message asking for loan amt
		cout<<"Input the total loan amount:\n";

		//input data
		cin>>LOAN_AMOUNT;

		//output message asking for interest rate
		cout<<"Input the annual interest rate:\n";

		//input data
		cin>>INT_RATE;
				
		//output message asking for term in years of loan
		cout<<"Input the length of the loan in years:\n";

		//input data
		cin>>TERM_YEARS;






		//Variable declarations
		float RATE=INT_RATE/100;		//converts interest rate into decimal format 
		float monthlyInterestRate;		//monthly interest rate
		int numberOfPayments;			//total number of payments
		float monthlyPaymentAmt;	 //monthly payment amount
		
		int monthly_payments_counter;//counter that keeps track of the payment number
		 
		
		float loanBalance=LOAN_AMOUNT;			 //loan balance
		float monthlyIntPymt;		 //monthly interest payment
		int divide_list = 0;		 //displays a partial list for the user
		char list_more;				 //enables the user to continue viewing a partial list
		float monthlyPrincipalPymt;	 //monthly principal payment
		
				 




		//CALCULATIONS
		//monthly interest rate
		monthlyInterestRate = RATE / 12; 
		
		//number of payments
		numberOfPayments = TERM_YEARS * 12; 
		
		//monthly payments
		monthlyPaymentAmt = (LOAN_AMOUNT*
			pow(monthlyInterestRate + 1, numberOfPayments)
			* monthlyInterestRate)/(pow(monthlyInterestRate + 1, 
			numberOfPayments) - 1); //pow returns x raised to the power of y

		//output results
		cout<<fixed<<setprecision(2)//cout writes text to the screen
			<<"\n";
		cout<<"Your monthly payment for "
			<<TERM_YEARS <<" years\n";
		cout<<"for an Interest Rate of "
			<<INT_RATE <<"%\n"; 
		cout<<"on a Loan Amount of $"
			<<LOAN_AMOUNT <<" is $"<<monthlyPaymentAmt<<" a month\n";
		cout<<"\n";
		cout<<"Payment Number\tLoan Balance\tInterest Paid\n";
		cout<<"--------------\t------------\t-------------\n";

		//List the payment number, loan balance, and interest paid 
		//for each period
		for (monthly_payments_counter=1; monthly_payments_counter<=(TERM_YEARS * 12); ++monthly_payments_counter)
		{	
			
		
		
			
			
			loanBalance = ((LOAN_AMOUNT * (1+monthlyInterestRate)) - (monthly_payments_counter * monthlyPaymentAmt));
			monthlyInterestRate = INT_RATE / 12;
			monthlyIntPymt = loanBalance * monthlyInterestRate;
			monthlyPrincipalPymt = monthlyPaymentAmt - (loanBalance * INT_RATE);
			loanBalance = loanBalance - monthlyPrincipalPymt;

			
			//displays a partial list and allows the user either continue viewing 
			//the list, enter a new loan, or exit the program
			if (divide_list == 12)
			{
				cout <<"Type 'c' to continue viewing the list, "
					 <<"'n' to enter a new loan, or 'e' to exit: ";
				cin >> list_more;

				if ((list_more == 'c') || (list_more == 'C'))
					divide_list = 0;
				else if ((list_more == 'n') || (list_more == 'N'))
					break;
				else if ((list_more == 'e') || (list_more == 'E'))
					return 0;
			}
			
			//displays the results on the screen for each payment number
			cout<<monthly_payments_counter<<"\t\t"
			<<loanBalance<<"\t"
			<<monthlyIntPymt<<"\t\t\n";
			++divide_list;

			if(loanBalance<=0)
				break;
			
			
		}
			
		//user can continue in a loop or quit
		//output
		cout<<"\n";
		cout<<"Enter C to continue, Q to quit >";

		//user input
		cin>>quit;
		cout<<"\n";

	}
	while (((quit!= 'q') && (quit!= 'Q')) || ((quit == 'c') && (quit == 'C')));

	cout<<"Thanks for using the calculator!\n";

	return 0;
		
}