/*
   Name: Assignment 2
   Author: muguangde
   Date: 2014-07-21-12.34
   Description: This is a simple program to read a text file with
   pay info for employees in Hollywood, net income were calculated
   according to their working hours and age, no matter they like it not.
   PS, maybe easier to use structure or class.
*/
#include <iostream>
#include <cstdlib>
#include <fstream>

using namespace std;

int main()
{
    float workHour,payRate,grossIncome;
    float tax(float,int);
    float grossPay(float,float);
    int age,maxAge=0,minAge=100;


    string firstName,lastName;
    string maxFirst,maxLast,minFirst,minLast;

    ifstream infile;
    ofstream outfile;
    infile.open("misercorp.txt");
    outfile.open("output.txt");
    outfile.setf(ios::fixed,ios::floatfield);

    if(!infile.is_open()) {
        //if the file can't be opened
        cout<<endl<<"Error: unable to open file."<<endl;
        system("PAUSE");
        exit(1);
    }

    //To read from file
    infile>>firstName>>lastName;
    outfile<<"\t***********************************************"<<endl;
    outfile<<"\t**********Miser Corporation Payroll************"<<endl;
    outfile<<"\t***********************************************"<<endl;
//Once read to the EOF, terminate the loop.
    while(!infile.eof()) {
        outfile<<firstName<<' '<<lastName<<endl;
        infile>>workHour>>payRate>>age;
        outfile.precision(2);
        outfile<<workHour<<'\t'<<payRate<<'\t'<<age;
        //To calculate gross income and max and min age
        grossIncome=grossPay(workHour,payRate);
        maxAge=(age>maxAge)? age:maxAge;
        minAge=(age<minAge)? age:minAge;

        outfile.precision(2);
        outfile<<endl<<"\nFor employee "<<firstName<<' '<<lastName
               <<", aged "<<age<<','<<" the rate of pay is "<<payRate
               <<"$/hrs,"<<endl<<"the working hours are "<<workHour
               <<" hours"<<", the base pay is $"
               <<grossPay(workHour,payRate)<<'.';
        outfile<<"\nThe tax he/she should pay is $"
               <<tax(grossIncome,age)
               <<", and the net pay is $"
               <<grossPay(workHour,payRate)-tax(grossIncome,age)<<endl;
        outfile<<"*********************************************"<<endl;
        //To get the name of oldest/youngest ones
        if(age==maxAge) {
            maxFirst=firstName;
            maxLast=lastName;
        }

        if(age==minAge) {
            minFirst=firstName;
            minLast=lastName;
        }
        infile>>firstName>>lastName;
    }//end of while

    //To print oldest and youngest employees
    outfile<<"\nThe oldest employee is "<<maxFirst<<' '<<
           maxLast<<", aged "<<maxAge<<endl;
    outfile<<"The youngest employee is "<<minFirst<<' '<<
           minLast<<", aged "<<minAge<<endl;
    outfile<<"\nJob done. End of the payroll."<<endl;

    infile.close();
    outfile.close();
    system("PAUSE");
    return 0;
}

float grossPay(float workHour,float payRate)
{
    float gross;
    if(workHour<=40)
        gross=workHour*payRate;
    else
        gross=(workHour-40)*payRate*1.5+40.0*payRate;
    return gross;//Return the grossPay
}

float tax(float grossIncome,int age)
{
    float tax;
    //Calculate grossPay first, pass it to here
    if(age>=55)
        tax=grossIncome*0.5;
    else
        tax=grossIncome*0.1;
    return tax;
}