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


using namespace std;

class Personnel
{
protected:
	int ssn;
	int nameLen;
	int cityLen;
	int yob;
	string salary;
	char* name;
	char* city;
public:
	Personnel() : nameLen(10), cityLen(10)
	{
		name = new char[nameLen + 1];
		city = new char[cityLen + 1];
	}
	Personnel(int nssn, int nyob, int nsalary, char* nname, char* ncity) : ssn(nssn), yob(nyob), salary(bitset<32>(nsalary).to_string()), nameLen(20), cityLen(20)
	{
		name = nname;
		city = ncity;
	}
	//for testing
	int getSsn() { return ssn; }
	int getYob() { return yob; }
	string getSalary() { return salary; }
	char* getName() { return name; }
	char* getCity() { return city; }

	//writes attributes of Personnel obj to file
	void writeToFile(fstream& out) const
	{
		out.write(name, nameLen);
		out.write(city, cityLen);
		out << ssn;
		stringstream salstream(salary);
		string temp;
		while (salstream.good())
		{
			bitset<8> bits;
			salstream >> bits;
			char c = char(bits.to_ulong());
			temp += c;
		}
		out << temp;
		out << yob;
		out << '\n';
	}
	//reads file and assigns stored values to Personnel obj
	void readFromFile(fstream& in)
	{
		char temp[5];
		in.read(name, nameLen);
		in.read(city, cityLen);
		char ssntemp[10];
		in.read(ssntemp, 9);
		ssn = atoi(ssntemp);
		in.read(temp, 4);
		salary = bitset<8>(temp[0]).to_string();
		salary = salary + bitset<8>(temp[1]).to_string();
		salary = salary + bitset<8>(temp[2]).to_string();
		salary = salary + bitset<8>(temp[3]).to_string();
		in.seekp(+1, ios::cur);
		char yobtemp[5];
		in.read(yobtemp, 4);
		yob = atoi(yobtemp);
		in.seekp(+1, ios::cur);

	}
	bool operator==(const Personnel &newP)
	{
		return this->ssn == newP.ssn;
	}
	int size()
	{
		return nameLen + cityLen + 4 + 9 + 4 + 2;
	}
	friend istream &operator >>(istream &in, Personnel &p)
	{
		int nsalary;
		cout << "Enter SSN:";
		in >> p.ssn;
		cout << "Enter year of birth: ";
		in >> p.yob;
		cout << "Enter Name: ";
		in.ignore(numeric_limits<streamsize>::max(), '\n');
		in.get(p.name, sizeof(p.name), '\n');
		cout << "Enter City: ";
		in.ignore(numeric_limits<streamsize>::max(), '\n');
		in.get(p.city, sizeof(p.city), '\n');
		cout << "Enter salary: ";
		in.ignore(numeric_limits<streamsize>::max(), '\n');
		in >> nsalary;
		p.salary = bitset<32>(nsalary).to_string();
		return in;
	}
};

class Student : public Personnel
{
private:
	char* major;//
	int majorLen;
public:
	char* getMajor() { return major; }//
	Student() :majorLen(30)
	{
		major = new char[majorLen];
	}
	void writeToFile(fstream& out) const
	{
		out.write(name, nameLen);
		out.write(city, cityLen);
		out << ssn;
		stringstream salstream(salary);
		string temp;
		while (salstream.good())
		{
			bitset<8> bits;
			salstream >> bits;
			char c = char(bits.to_ulong());
			temp += c;
		}
		out << temp;
		out << yob;
		out.write(major, majorLen);
		out << '\n';
	}
	void readFromFile(fstream& in)
	{
		char temp[5];
		in.read(name, nameLen);
		in.read(city, cityLen);
		char ssntemp[10];
		in.read(ssntemp, 9);
		ssn = atoi(ssntemp);
		in.read(temp, 4);
		salary = bitset<8>(temp[0]).to_string();
		salary = salary + bitset<8>(temp[1]).to_string();
		salary = salary + bitset<8>(temp[2]).to_string();
		salary = salary + bitset<8>(temp[3]).to_string();
		in.seekp(+1, ios::cur);
		char yobtemp[5];
		in.read(yobtemp, 4);
		yob = atoi(yobtemp);
		in.read(major, majorLen);
		in.seekp(+1, ios::cur);
	}
	int size()
	{
		return Personnel::size() + majorLen;
	}
	friend istream &operator >>(istream &in, Student &p)
	{
		int nsalary;

		cout << "Enter SSN:";
		in >> p.ssn;
		cout << "Enter year of birth: ";
		in >> p.yob;
		cout << "Enter Name: ";
		in.ignore(numeric_limits<streamsize>::max(), '\n');
		in.get(p.name, sizeof(p.name), '\n');
		cout << "Enter City: ";
		in.ignore(numeric_limits<streamsize>::max(), '\n');
		in.get(p.city, sizeof(p.city), '\n');
		cout << "Enter salary: ";
		in.ignore(numeric_limits<streamsize>::max(), '\n');
		in >> nsalary;
		p.salary = bitset<32>(nsalary).to_string();
		cout << "Enter major: ";
		in.ignore(numeric_limits<streamsize>::max(), '\n');
		in.get(p.major, sizeof(p.major), '\n');
		in.ignore(numeric_limits<streamsize>::max(), '\n');
		return in;

	}
};

template<class T>
class Database
{
private:
	fstream database;
public:
	Database()
	{}
	Database(string filename)
	{
		database.open(filename, fstream::out | fstream::in);
		if (!database.is_open())
		{
			database.open(filename, fstream::out | fstream::in | fstream::trunc);
		}
	}
	void print()
	{
		database.clear();
		database.seekp(0, ios::beg);
		string s;
		Personnel obj;
		int num = 0;
		cout << " = DATA = " << endl;
		do
		{
			obj.readFromFile(database);
			if (obj.getSsn() != 0)
			{
				cout << "Name: " << obj.getName() << endl;
				cout << "YOB: " << obj.getYob() << endl;
				cout << "SSN: " << obj.getSsn() << endl;
				cout << "City: " << obj.getCity() << endl;
				for (int i = 0; i < 32; i++)
				{
					if (obj.getSalary()[i] == '1') {
						num += pow(2, 31 - i);
					}
				}
				cout << "Salary: " << num << endl << endl;
				num = 0;
			}
		} while (getline(database, s));
		database.seekp(0, ios::beg);
	}
	//Student print
	void printS()
	{
		database.clear();
		database.seekp(0, ios::beg);
		string s;
		Student obj;
		int num = 0;
		cout << " = DATA = " << endl;
		do
		{
			obj.readFromFile(database);
			if (obj.getSsn() != 0)
			{
				cout << "Name: " << obj.getName() << endl;
				cout << "YOB: " << obj.getYob() << endl;
				cout << "SSN: " << obj.getSsn() << endl;
				cout << "City: " << obj.getCity() << endl;
				for (int i = 0; i < 32; i++)
				{
					if (obj.getSalary()[i] == '1') {
						num += pow(2, 31 - i);
					}
				}
				cout << "Salary: " << num << endl;
				cout << "Major: "<< obj.getMajor()<<endl<<endl;
				num = 0;
			}

		} while (getline(database, s));
		database.seekp(0, ios::beg);
	}
	//add file to end of database
	void add(T file)
	{
		database.seekp(0, ios::beg);
		if (!(this->find(file)))
		{
			database.clear();
			database.seekg(0, ios::end);
			file.writeToFile(database);
		}
		database.seekp(0, ios::beg);
	}
	bool find(T file)
	{
		database.clear();
		database.seekp(0, ios::beg);
		T p;
		string s;

		do
		{
			p.readFromFile(database);
			if (p == file)
			{
				return true;
			}
		} while (getline(database, s));
		return false;

	}
	//not done
	void modify(T file)
	{
		database.clear();
		database.seekp(0, ios::beg);
		if (this->find(file))
		{
			T editP;

			cout << "Please enter new information" << endl;
			cin >> editP;
			if (file.getSsn() == editP.getSsn())
			{
				database.seekp(-file.size(), ios::cur);
				editP.writeToFile(database);
			}
			else
			{
				cout << "Error. SSN does not match." << endl;
			}
		}
	}
};

template<class T>
void menu(string filename)
{
	Database<T> database(filename);
	int choice = 0;
	T newPerson;

	cout << "--- " << filename << " ---";
	do {
		cout << endl << "Options" << endl;
		cout << "1. New entry" << endl;
		cout << "2. Print database" << endl;
		cout << "3. Modify entry" << endl;
		cout << "4. Exit" << endl;
		cout << "Select: ";
		cin >> choice;
		cout << endl;
		bool isStudent = is_same<T, Student>::value;
		switch (choice) {
		case 1:
			cin >> newPerson;
			database.add(newPerson);
			break;
		case 2:
			if (!isStudent) {
				database.print();
				break;
			}
			else if (isStudent) {
				database.printS();
				break;
			}
		case 3:
			cout << "Please enter information (at least SSN) for Personnel to modify. Enter 0 if you don't know." << endl;
			cin >> newPerson;
			database.modify(newPerson);
			break;
		default: break;
		}
	} while (choice != 4);
}

//need menu
int main()
{
	/*  Database<Personnel> database("database.txt");
	char n[10] = { 'r','o','s','e' };
	char c[10] = { 'h','o' };
	char n2[10] = { 'q','w' };
	char c2[10] = { 's','d' };
	Personnel p(123456789, 1111, 50000, n, c);
	Personnel q(123456790, 1111, 50000, n2, c2);

	database.add(p);
	database.add(q);
	database.add(Personnel(111111111, 2222, 400, n, c));
	database.add(Personnel(333333333, 3333, 80, n2, c2));
	*/
	int option;
	string filename;
	do
	{
		cout << "Options " << endl;
		cout << "1. Create/Open Student database" << endl;
		cout << "2. Create/Open Personnel database" << endl;
		cout << "3. Exit" << endl << "Select: ";
		cin >> option;

		if (option == 1)
		{
			cout << "Enter database filename: ";
			cin >> filename;
			menu<Student>(filename);
		}
		else if (option == 2)
		{
			cout << "Enter database filename: ";
			cin >> filename;
			menu<Personnel>(filename);
		}


	} while (option != 3);


	return 0;
}