// assign_problem5.cpp : main project file.

#include "stdafx.h"

#include <iostream>
#include <conio.h>
#include <string>

using namespace System;
using namespace std;

//Prototypes
//Sets up the screen for entering data
void setScreenData(void);
//Sets up the screen for displaying stats
void setScreenStats(void);
//Checks for invalid marks
void invalidCheck(int & mark, int row);
//Calculates the student's result
void calcResult(int cwMark, int exMark, int & mark, string & grade, int & numStudents,
                int & cwSum, int & exSum, int & markSum, int gradeCount[]);
//Calculates the averages
void calcAvg(double & avgMark, double & cwAvg, double & exAvg, string & avgGrade,
             int numStudents, int cwSum, int exSum, int markSum);

int main(array<System::String ^> ^args)
{
    //Declare variables
    string name, grade, avgGrade;
    int x, cwMark, exMark, mark, numStudents = 0, markSum = 0, cwSum = 0, exSum = 0, gradeCount[5] = {0};
    double avgMark = 0.0, cwAvg = 0.0, exAvg = 0.0;
    char again;

    //Allow the user to enter student marks as many times they want
    do
    {
        //Set up the screen
        setScreenData();

        //Get the student name from the user
        Console::SetCursorPosition(51, 4);
        getline(cin, name);

        //Get the coursework mark from the user
        Console::SetCursorPosition(51, 6);
        cin >> cwMark;
        //Remove the last character (\n) from istream to avoid erros with getline
        cin.ignore();

        //Check if the user entered an invalid number
        invalidCheck(cwMark, 6);

        //Get the examination mark from the user
        Console::SetCursorPosition(51, 7);
        cin >> exMark;
        //Remove the last character (\n) from istream to avoid erros with getline
        cin.ignore();

        //Check if the user entered an invalid number
        invalidCheck(exMark, 7);

        //Calculate the student's result
        calcResult(cwMark, exMark, mark, grade, numStudents, cwSum, exSum, markSum, gradeCount);

        //Output the results
        Console::SetCursorPosition(51, 9); cout << mark;
        Console::SetCursorPosition(51, 10); cout << grade;

        //Ask the user if they would like to move on to the next student
        Console::SetCursorPosition(20, 24);
        cout << "Next student? (Y)es / (N)o [_]";

        //Get the user's reply
        Console::SetCursorPosition(48, 24);
        again = getche();

        //Convert again to lowercase
        again = tolower(again);

        //Show an error message and get another letter from the user if they enetered
        //an invalid option
        while(again != 'y' && again != 'n')
        {
            //Show an error message
            Console::SetCursorPosition(60, 24);
            cout << "Invalid option!";

            //Remove the letter the user entered
            Console::SetCursorPosition(48, 24);
            cout << " ]";

            //Get another letter from the user
            Console::SetCursorPosition(48, 24);
            again = getche();

            //Convert again to lowercase
            again = tolower(again);

            //Remove the error message
            Console::SetCursorPosition(60, 24);
            cout << "               ";
        }
    }while(again != 'n');

    //Set up the screen for showing statistics
    setScreenStats();

    //Calculate the averages
    calcAvg(avgMark, cwAvg, exAvg, avgGrade, numStudents, cwSum, exSum, markSum);

    //Output the grade counts
    for(x = 0; x < 5; x++)
    {
        Console::SetCursorPosition(41, x + 6);
        cout << gradeCount[x];
    }

    //Output the averages
    Console::SetCursorPosition(41, 12); cout << avgMark;
    Console::SetCursorPosition(41, 13); cout << avgGrade;

    Console::SetCursorPosition(41, 15); cout << cwAvg;
    Console::SetCursorPosition(41, 16); cout << exAvg;

    //Wait for a key press before exiting
    Console::SetCursorPosition(79, 24);
    getch();
}

void setScreenData(void)
{
    Console::Clear();

    Console::SetCursorPosition(30, 2); cout << "Computer Science grades";

    Console::SetCursorPosition(20, 4); cout << "Student name:";

    Console::SetCursorPosition(20, 6); cout << "Coursework mark:";
    Console::SetCursorPosition(20, 7); cout << "Examination mark:";

    Console::SetCursorPosition(20, 9); cout << "Mark:";
    Console::SetCursorPosition(20, 10); cout << "Grade:";

    Console::SetCursorPosition(50, 4); cout << "[                          ]";

    Console::SetCursorPosition(50, 6); cout << "[  ]";
    Console::SetCursorPosition(50, 7); cout << "[  ]";

    Console::SetCursorPosition(50, 9); cout << "[  ]";
    Console::SetCursorPosition(50, 10); cout << "[  ]";
}

void setScreenStats(void)
{
    Console::Clear();

    Console::SetCursorPosition(30, 2); cout << "Class statistics";

    Console::SetCursorPosition(10, 4); cout << "Number of students who achieved: ";

    Console::SetCursorPosition(10, 6); cout << "Grade A:";
    Console::SetCursorPosition(10, 7); cout << "Grade B+:";
    Console::SetCursorPosition(10, 8); cout << "Grade B:";
    Console::SetCursorPosition(10, 9); cout << "Grade C:";
    Console::SetCursorPosition(10, 10); cout << "Grade F:";

    Console::SetCursorPosition(10, 12); cout << "Class average mark:";
    Console::SetCursorPosition(10, 13); cout << "Class average grade:";

    Console::SetCursorPosition(10, 15); cout << "Average coursework mark:";
    Console::SetCursorPosition(10, 16); cout << "Average examination mark:";

    Console::SetCursorPosition(40, 6); cout << "[  ]";
    Console::SetCursorPosition(40, 7); cout << "[  ]";
    Console::SetCursorPosition(40, 8); cout << "[  ]";
    Console::SetCursorPosition(40, 9); cout << "[  ]";
    Console::SetCursorPosition(40, 10); cout << "[  ]";

    Console::SetCursorPosition(40, 12); cout << "[    ]";
    Console::SetCursorPosition(40, 13); cout << "[  ]";

    Console::SetCursorPosition(40, 15); cout << "[    ]";
    Console::SetCursorPosition(40, 16); cout << "[    ]";

    Console::SetCursorPosition(30, 24);
    cout << "Press any key to exit...";
}

void invalidCheck(int & mark, int row)
{
    //If the user enters an invalid number, show an error message and
    //get another number from them
    while(mark < 0 || mark > 50)
    {
        //Show an error message
        Console::SetCursorPosition(60, row);
        cout << "Invalid number!";

        //Remove the number the user entered
        Console::SetCursorPosition(51, row);
        cout << "  ]";

        //Get another number from the user
        Console::SetCursorPosition(51, row);
        cin >> mark;

        //Remove the error message
        Console::SetCursorPosition(60, row);
        cout << "               ";
    }
}

void calcResult(int cwMark, int exMark, int & mark, string & grade, int & numStudents,
                int & cwSum, int & exSum, int & markSum, int gradeCount[])
{
    //Calculate the total mark for the student
    mark = cwMark + exMark;

    //If the student scored lower than 40 but scored 15 in each component
    //allow them to pass
    if(mark < 40 && cwMark >= 15 && exMark >= 15)
        mark = 40;
    else
        //If the student scored 40 or more but did not score at least 15
        //in each component, fail them
        if(mark >= 40 && (cwMark < 15 || exMark < 15))
            mark = 39;

    //Calculate the grade
    if(mark >= 70)
    {
        grade = "A";

        //Increase the number of A's
        gradeCount[0]++;
    }
    else
    {
        if(mark >= 60)
        {
            grade = "B+";

            //Increase the number of B+'s
            gradeCount[1]++;
        }
        else
        {
            if(mark >= 50)
            {
                grade = "B";

                //Increase the number of B's
                gradeCount[2]++;
            }
            else
            {
                if(mark >= 40)
                {
                    grade = "C";

                    //Increase the number of C's
                    gradeCount[3]++;
                }
                else
                {
                    grade = "F";

                    //Increase the number of F's
                    gradeCount[4]++;
                }
            }
        }
    }

    //Add cwMark to cwSum
    cwSum += cwMark;

    //Add exMark to exSum
    exSum += exMark;

    //Add mark to markSum
    markSum += mark;

    //Increase the number of students
    numStudents++;
}

void calcAvg(double & avgMark, double & cwAvg, double & exAvg, string & avgGrade,
             int numStudents, int cwSum, int exSum, int markSum)
{
    //Calculate class average mark
    avgMark = static_cast<double>(markSum) / numStudents;

    //Calculate the class average grade
    if(avgMark >= 70)
        avgGrade = "A";
    else
        if(avgMark >= 60)
            avgGrade = "B+";
        else
            if(avgMark >= 50)
                avgGrade = "B";
            else
                if(avgMark >= 40)
                    avgGrade = "C";
                else
                    avgGrade = "F";

    //Calculate the average coursework mark
    cwAvg = static_cast<double>(cwSum) / numStudents;

    //Calculate the average examination mark
    exAvg = static_cast<double>(exSum) / numStudents;
}