Database.h

// Database.h
#pragma once
#include <iostream>
#include "Employee.h"
#include "vector"
#include "string"

namespace Records
{
    const int FirstEmployeeNumber{1'000};
    class Database
    {
    public:
        Employee &addEmployee(const std::string &firstName,
                              const std::string &lastName);

        Employee &getEmployee(int employeeNumber);

        Employee &getEmployee(const std::string &firstName,
                              const std::string &lastName);
        void displayAll() const;
        void displayCurrent() const;
        void displayFormer() const;

    private:
        std::vector<Employee> m_employees;
        int m_nextEmployeeNumber{FirstEmployeeNumber};
    };
}