/*
    Method8.java
    CIS 160
    10/18/04

    payroll calculation example using methods
*/

import java.io.*;
import java.text.*;

class EmployeeRecord {
    public String employeeName ="";
    public double hourlyRate=0.0, hoursWorked=0.0, taxRate=0.0;
    public double grossAmount=0.0, netAmount=0.0;
}

public class Method8 {
    private static double totalGross = 0.0;
    private static double totalNet = 0.0;    
    
    public static void main(String[] args) throws IOException {
        EmployeeRecord rec = new EmployeeRecord();
        BufferedReader in = new BufferedReader(new FileReader("paydata.txt"));
        int numRecs = 0;

        instructions();
        reportTitle();
        while (getInput(in, rec)) {
            numRecs++;
            processPay(rec);
            printEmployeeInfo(rec.employeeName, rec.hourlyRate, rec.hoursWorked,
                rec.taxRate, rec.grossAmount, rec.netAmount);
            totalAmounts(rec.grossAmount, rec.netAmount);
        }
        in.close();
        DecimalFormat df = new DecimalFormat("0.00");
        System.out.println("Totals" + leftPad(df.format(totalGross),54)
            + leftPad(df.format(totalNet),10));
    }

    private static boolean getInput(BufferedReader in, EmployeeRecord r) {

        try {
            r.employeeName = in.readLine();
            r.hourlyRate = Double.parseDouble(in.readLine());
            r.hoursWorked = Double.parseDouble(in.readLine());
            r.taxRate = Double.parseDouble(in.readLine());
        } catch (IOException e1) {
            return false;
        } catch (NumberFormatException e2) {
            return false;
        } catch (NullPointerException e3) {
            return false;
        }
        return true;
    }
        
    private static void instructions() {
        System.out.println("                    Instructions for Payroll Report Program");
        System.out.println("This program calculates a paycheck for each employee.");
        System.out.println("A text file will be created outside of the program with the");
        System.out.println("following information:");
        System.out.println("    name, rate of pay, hours worked, and tax percentage");
        System.out.println("");
        System.out.println("The program will create a report in columnar format showing");
        System.out.println("the employee name, hourly rate, number of hours worked, tax rate,");
        System.out.println("gross pay, and net pay.");
        System.out.println("");
        System.out.println("After all employees are processed, totals will be displayed,");
        System.out.println("including total gross amount and total net pay.");
        System.out.println("");
    }

    private static void reportTitle() {
        System.out.println("                            Payroll Report");
        System.out.println("Employee                Hourly    Hours       Tax     Gross     Net");
        System.out.println("Name                    Rate      Worked      Rate    Amount    Amount");
        System.out.println("");
    }

    private static void printEmployeeInfo(String eName, double hRate, double hours,
        double taxRate, double gross, double net) {
        DecimalFormat df = new DecimalFormat("0.00");
        System.out.println(rightPad(eName, 20) + leftPad(df.format(hRate), 10)
            + leftPad(df.format(hours), 10) + leftPad(df.format(taxRate), 10)
            + leftPad(df.format(gross), 10)
            + leftPad(df.format(net), 10));
    }

    private static String leftPad(String s, int width) {
        if (width < s.length()) s = s.substring(0,width);
        while (width > s.length()) s = " " + s;
        return s;
    }

    private static String rightPad(String s, int width) {
        if (width < s.length()) s = s.substring(0,width);
        while (width > s.length()) s += " ";
        return s;
    }

    private static void processPay(EmployeeRecord r) {
            r.grossAmount = calcGross(r.hourlyRate, r.hoursWorked);
            double tax = (r.taxRate/100) * r.grossAmount;
            r.netAmount = r.grossAmount - tax;
    }

    private static double calcGross(double hRate, double hours) {
        double gross = hours * hRate;
        if (hours > 40) gross += (hours-40) * (hRate/2);
        return gross;
    }

    private static void totalAmounts(double gross, double net) {
        totalGross += gross;
        totalNet += net;
    }
}