// FILE: Payroll.cpp
// CREATES A COMPANY EMPLOYEE PAYROLL FILE
//    COMPUTES TOTAL COMPANY PAYROLL AMOUNT

#include <fstream.h>		// required for file streams
#include <stdlib.h>		// for definition of EXIT_FAILURE
					//     & EXIT_SUCCESS
#include "money.h"		// process employee data

// ASSOCIATE PROGRAM IDENTIFIERS WITH EXTERNAL FILE NAMES
#define in_file "Emp_File.dat"	// employee file
#define out_file "Salary.dat"	// payroll file

// Functions used ...
   // PROCESS ALL EMPLOYEES AND COMPUTE TOTAL
   money process_emp
     (ifstream&,	// IN: employee data stream
      ofstream&);	// IN: payroll data stream

int main()
{
   // Local data ...
   ifstream eds;			// input: employee data stream
   ofstream pds;			// output: payroll data stream
   money total_payroll;		// output: total payroll

   // Prepare files.
   eds.open (in_file);
   if (eds.fail())
   {
      cerr << "*** ERROR: Cannot open " << in_file
             << " for input." << endl;
      return EXIT_FAILURE;	// failure return
   }
   pds.open(out_file);
   if (pds.fail())
   {
      cerr << "***ERROR: Cannot open " << out_file
             << " for output." << endl;
      eds.close ();
      return EXIT_FAILURE;	// failure return
   }

   // Set precision and flags for floating point output.
   cout.precision (2);
   cout.setf (ios::fixed);

   // Process all employees and compute total payroll.
   total_payroll = process_emp (eds, pds);

   // Display result.
   cout << "Total payroll is " << total_payroll << endl;

   // Close files.
   eds.close ();
   pds.close ();
   return EXIT_SUCCESS;	// successful return
}

// PROCESS ALL EMPLOYEES AND COMPUTE TOTAL PAYROLL AMOUNT
#include "apstring.h"

money process_emp
  (ifstream& eds,			// IN: employee file stream
   ofstream& pds)		// IN: payroll file stream
// Pre:  eds and pds are prepared for input/output.
// Post: Employee names and salaries are written from eds to pds
//       and the sum of their salaries is returned.
// Returns: Total company payroll

{
   apstring first_name;		// input: employee first name
   apstring last_name;		// input: employee last name
   double hours;			// input: hours worked
   money rate;			// input: hourly rate
   money salary;			// output: gross salary
   money payroll;			// return value - total company payroll

   // set for floating point output
   pds.setf (ios::fixed);
   pds.precision (2);

   payroll = 0.0;
   // Read first employee's data record.
   eds >> first_name >> last_name >> hours >> rate;
   while (!eds.eof ())
   {
      salary = hours * rate;
      pds << first_name << last_name << salary << endl;
      payroll += salary;

      // Read next employee's data record.
      eds >> first_name >> last_name >> hours >> rate;
   }  // end while
   return payroll;
}  // end process_emp