/******************************************************************************
 * This program...
 * 
 * Copyright © 2020 Richard Lesh.  All rights reserved.
 *****************************************************************************/

#undef NDEBUG

#include "Utils.hpp"
#include <cmath>
#include <fmt/format.h>
#include <iostream>
#include <string>

using namespace Utils;
using namespace std;

int main(int argc, char **argv) {
    if (argc != 4) {
        cout << fmt::format("Syntax: {0:s} loan_amount rate_per_annum term_in_years", argv[0]) << endl;
        exit(1);
    }

    long balance = Utils::stolWithDefault(string(argv[1]), 0) * 100;
    double interest_rate = Utils::stodWithDefault(string(argv[2]), 0.05);
    interest_rate /= 12.0;
    int periods = Utils::stoiWithDefault(string(argv[3]), 30);
    periods *= 12;
    long payment(interest_rate * balance / (1.0 - pow(1.0 + interest_rate, -periods)) + 0.5);

    cout << "Month\tPayment\tPrinciple\tInterest\tBalance" << endl;
    cout << fmt::format("0\t\t\t\t{0:.2f}", balance / 100.0) << endl;
    for (int i = 0; i < periods; ++i) {
        long const INTEREST = long(balance * interest_rate + 0.5);
        long principle = payment - INTEREST;
        balance -= principle;
        if (i == periods - 1) {
            payment += balance;
            principle += balance;
            balance = 0;
        }
        cout << fmt::format("{0:d}\t{1:.2f}\t{2:.2f}\t{3:.2f}\t{4:.2f}", i + 1, payment / 100.0, principle / 100.0, INTEREST / 100.0, balance / 100.0) << endl;
    }
    return 0;
}