#include <iostream>
#include <string>
#include <vector>
#include <fstream>
#include <iomanip>
#include <sstream>
#include <stdlib.h>

using namespace std;

struct Students
{
    string Surname;
    string Name;
    string Patronymic;
    int Age;
    string Sex;
    int Course;
    double Progress;

    Students(string Su, string Na, string Pa, int Ag, string Se, int Co, double Pr) : Surname(Su), Name(Na), Patronymic(Pa), Age(Ag), Sex(Se), Course(Co), Progress(Pr) {}
};

void CreateFile(char FileName[50])
{
    ofstream F(FileName);

    F.close();

    cout << "txt file to the data base of students ready!"  << endl;

}

void Save(vector<Students*> &Stud, char FileName[50])
{
    ofstream F(FileName);

    for (int i = 0; i < Stud.size(); i++)
    {
        F << Stud[i]->Surname << "|";
        F << Stud[i]->Name << "|";
        F << Stud[i]->Patronymic << "|";
        F << Stud[i]->Age << "|";
        F << Stud[i]->Sex << "|";
        F << Stud[i]->Course << "|";
        F << Stud[i]->Progress << endl;
    }
    F.close();
}

vector<string> explode(string const &s, char delim)
{
    vector<string> result;
    istringstream iss(s);

    for (string token; getline(iss, token, delim); )
    {
        result.push_back(move(token));
    }

    return result;
}

void Input(vector<Students*> &Stud, char FileName[50])
{
    ifstream Student(FileName);
    if (!Student){}
    else
    {
        string s;
        vector<string> temp;

        while (getline(Student, s))
        {
            temp = explode(s, '|');
            Stud.push_back(new Students(temp[0], temp[1], temp[2], atoi(temp[3].c_str()), temp[4], atoi(temp[5].c_str()), atof(temp[6].c_str())));
        }
    }
}

void Output(vector<Students*> &Stud, char FileName[50])
{
    int opinion;
    ifstream Student(FileName);
    if (!Student)
    {
        cout << "File not found!" << endl << "Do you want to create a file for the data base of students?" << endl << "1. Yes" << endl << "2. No " << endl;
        cin >> opinion;
        if(opinion == 1) CreateFile(FileName);
    }
    else
    {
        int count = 0;
        for (int i = 0; i < Stud.size(); i++)
        {
            count++;
        }
        if (count == 0) cout << "No entries yet!" << endl;
        else
        {
            for (int i = 0; i < Stud.size(); i++)
            {
                cout << i << "    ";
                cout << Stud[i]->Surname << "  ";
                cout << Stud[i]->Name << "  ";
                cout << Stud[i]->Patronymic << "  ";
                cout << Stud[i]->Age << "  ";
                cout << Stud[i]->Sex << "  ";
                cout << Stud[i]->Course << "  ";
                cout << Stud[i]->Progress << endl;
            }
        }
        count = 0;
    }
}

void AddStudent(vector<Students*> &Stud, char FileName[50])
{
    int opinion;

    ifstream F(FileName);
    if (!F)
    {
        cout << "File not found!" << endl << "Do you want to create a file for the data base of students?" << endl << "1. Yes" << endl << "2. No " << endl;
        cin >> opinion;
        if(opinion == 1)
        {
            CreateFile(FileName);

            Stud.push_back(new Students("", "", "", 0, "", 0, 0));

            cout << "Surname: "; cin >> Stud[Stud.size()-1]->Surname;
            cout << "Name: "; cin >> Stud[Stud.size()-1]->Name;
            cout << "Patronymic: "; cin >> Stud[Stud.size()-1]->Patronymic;
            cout << "Age: "; cin >> Stud[Stud.size()-1]->Age;
            cout << "Sex: "; cin >> Stud[Stud.size()-1]->Sex;
            cout << "Course: "; cin >> Stud[Stud.size()-1]->Course;
            cout << "Progress: "; cin >> Stud[Stud.size()-1]->Progress;

            Save(Stud, FileName);
        }
    }
    else
    {
        Stud.push_back(new Students("", "", "", 0, "", 0, 0));

        cout << "Surname: "; cin >> Stud[Stud.size()-1]->Surname;
        cout << "Name: "; cin >> Stud[Stud.size()-1]->Name;
        cout << "Patronymic: "; cin >> Stud[Stud.size()-1]->Patronymic;
        cout << "Age: "; cin >> Stud[Stud.size()-1]->Age;
        cout << "Sex: "; cin >> Stud[Stud.size()-1]->Sex;
        cout << "Course: "; cin >> Stud[Stud.size()-1]->Course;
        cout << "Progress: "; cin >> Stud[Stud.size()-1]->Progress;

        Save(Stud, FileName);
    }
}

void FindSttudentsNCourse(vector<Students*> &Stud, char FileName[50])
{
    int opinion;
    ifstream Student(FileName);
    if (!Student)
    {
        cout << "File not found!" << endl << "Do you want to create a file for the data base of students?" << endl << "1. Yes" << endl << "2. No " << endl;
        cin >> opinion;
        if(opinion == 1) CreateFile(FileName);
    }
    else
    {
        int count = 0;
        for (int i = 0; i < Stud.size(); i++)
        {
            count++;
        }
        if (count == 0) cout << "No entries yet!" << endl;
        else
        {

            char New[50] = "/Users/CoolGeek/Documents/SixStudent.txt";

            ofstream F(New);

            int temp;
            cout << "Input course: ";
            cin >> temp;

            for (int i = 0; i < Stud.size(); i++)
            {
                if (Stud[i]->Course == temp)
                {
                    F << i << "    ";
                    F << Stud[i]->Surname << "  ";
                    F << Stud[i]->Name << "  ";
                    F << Stud[i]->Patronymic << "  ";
                    F << Stud[i]->Age << "  ";
                    F << Stud[i]->Sex << "  ";
                    F << Stud[i]->Course << "  ";
                    F << Stud[i]->Progress << endl;
                }
            }
            cout << "txt file to the data base of students ready!"  << endl;
            F.close();
        }
        count = 0;
    }
}

void DeleteStudent(vector<Students*> &Stud, char FileName[50])
{
    int opinion;

    ifstream F(FileName);
    if(!F)
    {
        cout << "File not found!" << endl << "Do you want to create a file for the data base of students?" << endl << "1. Yes" << endl << "2. No " << endl;
        cin >> opinion;
        if(opinion == 1)
        {
            CreateFile(FileName);
        }

    }
    else
    {
        int count = 0;
        for (int i = 0; i < Stud.size(); i++)
        {
            count++;
        }

        if (count == 0) cout << "No entries yet!" << endl;
        else
        {
            int temp;
            cout << "Input ID: ";
            cin >> temp;

            Stud.erase(Stud.begin() + temp);
            Save(Stud, FileName);
            }
        count = 0;
    }
}

void EditStudent(vector<Students*> &Stud, char FileName[50])
{
    int opinion;

    ifstream F(FileName);
    if (!F)
    {
        cout << "File not found!" << endl << "Do you want to create a file for the data base of students?" << endl << "1. Yes" << endl << "2. No " << endl;
        cin >> opinion;
        if(opinion == 1)
        {
            CreateFile(FileName);
        }
    }
    else
    {
        int count = 0;
        for (int i = 0; i < Stud.size(); i++)
        {
            count++;
        }
        if (count == 0) cout << "No entries yet!" << endl;
        else
        {
            int temp;
            cout << "Input ID: ";
            cin >> temp;

            cout << "Surname: "; cin >> Stud[temp]->Surname;
            cout << "Name: "; cin >> Stud[temp]->Name;
            cout << "Patronymic: "; cin >> Stud[temp]->Patronymic;
            cout << "Age: "; cin >> Stud[temp]->Age;
            cout << "Sex: "; cin >> Stud[temp]->Sex;
            cout << "Course: "; cin >> Stud[temp]->Course;
            cout << "Progress: "; cin >> Stud[temp]->Progress;
        }
        count = 0;
    }
}

int main()
{
    vector<Students*> Stud;
    char FileName[50] = "/Users/CoolGeek/Documents/students.txt";

    int menu;

    do
    {
        cout << endl << "1. Create a txt file to store database (required for first start)" << endl
        << "2. View the contents of a databaseа." << endl
        << "3. Add an entry in the database." << endl
        << "4. Delete an entry from the database." << endl
        << "5. Edit entry in the database" << endl
        << "6. Students N rate" << endl
        << "0. Exit" << endl << endl;

        cout << "Select action: "; cin >> menu;

        switch (menu) {

            case 1:
            {
                ifstream F(FileName);
                if (!F) CreateFile(FileName);
                else cout << "The file has already been created and is ready to use!" << endl;
                break;
            }

            case 2:
            {
                Input(Stud, FileName);
                Output(Stud, FileName);
                Stud.clear();
                break;
            }

            case 3:
            {
                Input(Stud, FileName);
                AddStudent(Stud, FileName);
                Stud.clear();
                break;
            }

            case 4:
            {
                Input(Stud, FileName);
                DeleteStudent(Stud, FileName);
                Stud.clear();
                break;
            }

            case 5:
            {
                Input(Stud, FileName);
                EditStudent(Stud, FileName);
                Stud.clear();
                break;
            }

            case 6:
            {
                Input(Stud, FileName);
                FindSttudentsNCourse(Stud, FileName);
                Stud.clear();
                break;
            }

            case 0:
            {
                cout << "Bye!" << endl;
                break;
            }

            default:
            {
                cout << "ERROR!" << endl;
                break;
            }
        }
    }
    while (menu != 0);

    return 0;
}