//Kevin Pavao
//School: FAU
//Class: ISM3230
//Written: 11/5/06
//purpose: input male and female student GPAs in a class and write the list and the average to a file
//GenderGrades.cpp

#include<iostream>
#include<string>
#include<fstream>
#include<iomanip>

using namespace std;

//writes to the file chosen
void input(int file);

//averages the gpa
double average(double gpa, double numGrades);

//if invalid data entered, requests user to enter again
void reEnter(char &resp, string type);

//clears screen
void clear();


int main()
{
	char resp='y';
	int file; //what file to open

	do
	{
		clear();
		//menu
		cout << "1. historyData.dat" << endl;
		cout << "2. politicalscienceData.dat" << endl;
		cout << "3. scienceData.dat" << endl;

		cout << endl << "Which file would you like to open? 1, 2 or 3: ";
		cin >> file;

		clear();

		input(file);

		cout << "File written.\n";
		cout << "Open another file? (y/n): ";
		cin >> resp;
		if(resp!='Y' && resp!='y' && resp!='n' && resp!='N') //if invalid char entered
			reEnter(resp,"continue");
		clear();
	}while((resp=='Y' || resp=='y') && (resp!='n' || resp!='N')); //continues until N or n is input


	return 0;
}

void input(int file)
{
	ofstream outfile;
	char gender;
	char resp='y';
	double gpa, maleGPA=0.0, femaleGPA=0.0;
	int numMale=0, numFemale=0; //total number of males and females for averaging

   if(file==1)
	{
		outfile.open("historyData.dat");
		outfile << "Class: HST3239 History" << endl << endl;
	}
	if(file==2)
	{
		outfile.open("politicalscienceData.dat");
		outfile << "Class: POL5695 Political Science" << endl << endl;
	}
	if(file==3)
	{
		outfile.open("scienceData.dat");
		outfile << "Class: SCI3460 Science" << endl << endl;
	}

	//headings for the columns
	outfile << left << setw(10) << "Gender";
	outfile << right << setw(10) << "GPA" << endl;

	//continue until N or n is input
	while((resp=='Y' || resp=='y') && (resp!='n' || resp!='N'))
	{
		clear();
		cout << "Is the student male or female? (m/f): ";
		cin >> gender;
		if(gender!='M' && gender!='m' && gender!='F' && gender!='f')
			reEnter(gender,"gender");
		outfile << left << setw(10) << gender; //doesnt write to file until m or f is input

		cout << "Enter student GPA: ";
		cin >> gpa;
		outfile << setprecision(2) << setiosflags(ios::showpoint) << setiosflags(ios::fixed);
		outfile << right << setw(10) << gpa << endl; //write GPA to file with 2 decimal points

		if(gender=='M' || gender=='m')
		{
			maleGPA+=gpa; //adds gpa to total male gpa for averaging
			numMale++;
		}
		else
		{
			femaleGPA+=gpa; //adds gpa to total female gpa for averaging
			numFemale++;
		}

		clear();

		cout << "Is there another student? (y/n): ";
		cin >> resp;
		if(resp!='Y' && resp!='y' && resp!='n' && resp!='N')
			reEnter(resp, "continue");
	}

	outfile << setprecision(2) << setiosflags(ios::showpoint) << setiosflags(ios::fixed);

	//writes averages to file
	outfile << "\nNumber of males: " << numMale << endl;
	outfile << "Average male GPA: ";
	outfile << average(maleGPA,numMale) << endl << endl;
	outfile << "Number of females: " << numFemale << endl;
	outfile << "Average female GPA: ";
	outfile << average(femaleGPA,numFemale) << endl << endl;
	outfile << "Total average: ";
	outfile << average(femaleGPA+maleGPA,numFemale+numMale) << endl; //adds male and female GPA's
	outfile.close();

}

double average(double gpa, double numGrades)
{
	double avg=gpa/numGrades;
	return avg;
}

void reEnter(char &resp, string type)
{

	//if gender is not M or F
	if(type=="gender")
	{
		do
		{
			cout << "Invalid data entered, please enter M or F: ";
			cin >> resp;
		}while(resp!='M' && resp!='m' && resp!='F' && resp!='f');
	}


	//if value is not Y or N
	if(type=="continue")
	{
		do
		{
			cout << "Invalid data entered, continue? (y/n) ";
			cin >> resp;
		}while(resp!='Y' && resp!='y' && resp!='n' && resp!='N');
	}
}

void clear()
{
	for(int x=0; x<=50; x++)
		cout << endl;
}