#include<iostream>
#include<fstream>
#include<cstring>
using namespace std;

const int SIZE = 15;
struct Employee
{
   char fname[20];
   char lname[20];
   int hours;
   double rate;
   double regPay;
   double overtimePay;
   double totalPay;
};

struct OTPay
{
   double overtimePay;
   long int pos;
};

struct TotalPay
{
   double totalPay;
   long int pos;
};

struct NameIndex
{
   char lname[20];
   long int pos;
};

void sortOTPay(OTPay[]);
void sortTotalPay(TotalPay[]);
void displayByOTPay(ifstream&,OTPay[]);
void displayByTotalPay(ifstream&,TotalPay[]);
void getEmployee(ifstream&,char *,NameIndex[]);

int main()
{
   Employee emp;
   OTPay byOTPay[SIZE];
   TotalPay byTotalPay[SIZE];
   NameIndex byName[SIZE];
   ifstream infile;
   int cnt=0;
   
   infile.open("employees2.bin",ios::binary);
   infile.read((char *)&emp,sizeof(Employee));

   while(!infile.eof())
   {
      byOTPay[cnt].overtimePay = emp.overtimePay;
      byTotalPay[cnt].totalPay = emp.totalPay;
      strcpy(byName[cnt].lname,emp.lname);
      byOTPay[cnt].pos = cnt*sizeof(Employee);
      byTotalPay[cnt].pos = cnt*sizeof(Employee);
      byName[cnt].pos = cnt*sizeof(Employee);
      cnt++;
      infile.read((char *)&emp,sizeof(Employee));
   }
   infile.clear(); //program won't give good results without this!
   sortOTPay(byOTPay);
   sortTotalPay(byTotalPay);
   cout << "\nRecords sorted by overtime pay-->\n\n";
   displayByOTPay(infile,byOTPay);
      cout << "\nRecords sorted by total pay-->\n\n";
   displayByTotalPay(infile,byTotalPay);

   char lname[20];
   cout << "Enter last name of Employee: ";
   cin >> lname;
   getEmployee(infile,lname,byName);
   infile.close();

   return 0;
}
 
void sortOTPay(OTPay ot[])
{
   OTPay temp;

   for(int i=0;i<SIZE;i++)
      for(int j=0;j<SIZE-1;j++)
         if(ot[j].overtimePay < ot[j+1].overtimePay)
         {
            temp = ot[j];
            ot[j]= ot[j+1];
            ot[j+1] = temp;
         }
}

void sortTotalPay(TotalPay tp[])
{
   TotalPay temp;
   for(int i=0;i<SIZE;i++)
      for(int j=0;j<SIZE-1;j++)
         if(tp[j].totalPay < tp[j+1].totalPay)
         {
            temp = tp[j];
            tp[j] = tp[j+1];
            tp[j+1] = temp;
         }
}

void displayByOTPay(ifstream& f,OTPay ot[])
{
   Employee emp;
   for(int i=0;i<SIZE;i++)
   {
      f.seekg(ot[i].pos);
      f.read((char *)&emp,sizeof(Employee));
      cout << emp.lname << " " << emp.overtimePay << endl;
   }
}

void displayByTotalPay(ifstream& f,TotalPay tp[])
{
   Employee emp;
   for(int i=0;i<SIZE;i++)
   {
      f.seekg(tp[i].pos);
      f.read((char *)&emp,sizeof(Employee));
      cout << emp.lname << " " << emp.totalPay << endl;
   }
}

void getEmployee(ifstream& f,char *name,NameIndex index[])
{
   bool found = false;
   long int pos;
   Employee emp;
   for(int i=0;i<SIZE;i++)
   {
      if(strcmp(name,index[i].lname) == 0)
      {
         found = true;
         pos = index[i].pos;
         break;
      }
   }
   if(!found)
   {
      cout << name << "is not in database\n";
   }
   else
   {
      cout << "pos = " << pos << endl;
      f.seekg(pos);
      f.read((char *)&emp,sizeof(Employee));
      cout << emp.lname << '\t' << emp.fname
         << '\t' << emp.hours
         << '\t' << emp.totalPay << endl;
   }
}