using menushell.Models;
using System;
using System.Collections.Generic;
using System.Linq;

namespace menushell.Data
{
    public static class Database
    {
        private static UserEntities _userEntities = new UserEntities();

        public static IEnumerable<User> Users => _userEntities.Users.Values;

        public static void LoadUsers()
        {
            _userEntities.LoadMockUser();
        }

        public static bool TryAddUser(User user)
        {
            user.Id = Users.Count();
            return _userEntities.Users.TryAdd(user.Id, user);
        }

        public static bool TryRemoveUser(User user)
        {
            return _userEntities.Users.Remove(user.Id);
        }
    }
-------
using menushell.Models;
using System;
using System.Collections.Generic;

namespace menushell.Data
{
    public class UserEntities
    {
        public Dictionary<int, User> Users = new Dictionary<int, User>();

        public void LoadMockUser()
        {
            Users.Add(0, new User() { Id = 0, Username = "Reiko", Password = "abc123" });
        }
    }
}
----
namespace menushell.Models
{
    public class User
    {
        public int Id { get; set; }
        public int ID { get; internal set; }
        public string Username { get; set; }
        public string Password { get; set; }
        public object Name { get; internal set; }
    }
}
-----
using System;

namespace menushell.Views
{
    public class AdminView : menushellView
    {
        public override void Display()
        {
            ClearPreviousView();

            Console.WriteLine($"Welcome to the administrative view, {Program.CurrentUser.Username}!");
            Console.WriteLine("F1. Delete user");
            Console.WriteLine("F2. Logout");

            var input = Console.ReadKey();
            menushellView view;
            switch (input.Key)
            {
                case ConsoleKey.F1:
                    view = new DeleteUserView();
                    break;
                case ConsoleKey.F2:
                    Program.CurrentUser = null;
                    view = new MenuView();
                    break;
                default:
                    Display();
                    return;
            }

            view.Display();
        }
    }
}
-----
namespace menushell.Views
{
    public class CreateUserView : menushellView
    {
        public override void Display()
        {
            ClearPreviousView();

            Console.WriteLine("Creating new user...");
            Console.WriteLine();
            Console.Write("Enter the username: ");
            var username = Console.ReadLine();

            Console.WriteLine();

            Console.Write("Enter the password: ");
            var password = Console.ReadLine();

            Console.WriteLine();

            Console.Write("Confirm the password: ");
            var passwordConfirmation = Console.ReadLine();

            if (password != passwordConfirmation)
            {
                Display();
                return;
            }

            Database.TryAddUser(new User() { Username = username, Password = password });
            Console.WriteLine("User added to the database! Press any key to return to the main menu...");
            Console.ReadKey();

            var view = new MenuView();
            view.Display();
        }
    }
}
-----
namespace menushell.Views
{
    public class DeleteUserView : menushellView
    {
        public override void Display()
        {
            ClearPreviousView();

            Console.WriteLine("Currently deleting user...");
            Console.WriteLine();
            Console.Write("Enter the username of user: ");
            var username = Console.ReadLine();
            Console.WriteLine();

            var user = Database.Users.FirstOrDefault(u => u.Username == username);
            if (user == default(User))
            {
                Display();
                return;
            }

            menushellView view;
            Console.WriteLine($"Confirm: Delete user {user.Username}? F1 to delete, any other key to cancel.");
            if (Console.ReadKey().Key == ConsoleKey.F1)
            {
                    if (Database.TryRemoveUser(user))
                    {
                        if (user == Program.CurrentUser)
                            Program.CurrentUser = null;

                        ClearPreviousView();
                        Console.WriteLine($"User {user.Username} deleted! Press any key to return to the main menu...");
                        Console.ReadKey();
                    }
                    else
                    {
                        ClearPreviousView();
                        Console.WriteLine($"Error attempting to delete user {user.Username}. Press any key to return to the main menu...");
                        Console.ReadKey();
                    }
            }

            if (Program.CurrentUser == null)
                view = new MenuView();
            else view = new AdminView();

            view.Display();
        }
    }
}
-----
namespace menushell.Views
{
    class ListUserView
    {
        public static void ListUsers(List<User> users)
        {
            Console.Clear();
            foreach (User user in users)
            {
                Console.WriteLine(user.Username);
            }
            Console.ReadKey();
        }
    }
}
------
namespace menushell.Views
{
    public class LoginView : menushellView
    {
        public override void Display()
        {
            ClearPreviousView();

            menushellView view;

            Console.WriteLine("Attemping to login... type exit at any time to exit to the main menu.");
            Console.WriteLine();
            Console.Write("Username: ");
            var username = Console.ReadLine();
            if (username.ToLower() == "exit")
            {
                view = new MenuView();
                view.Display();
                return;
            }

            Console.Write("Password: ");
            var password = Console.ReadLine();
            if (password.ToLower() == "exit")
            {
                view = new MenuView();
                view.Display();
                return;
            }

            var user = Database.Users.FirstOrDefault(u => u.Username.ToLower() == username.ToLower() && u.Password == password);
            if (user == default(User))
            {
                Display();
                return;
            }

            Program.CurrentUser = user;

            view = new AdminView();
            view.Display();
        }
    }
}
---
namespace menushell.Views
{
    public abstract class menushellView
    {
        public abstract void Display();

        public void ClearPreviousView()
        {
            Console.Clear();
        }
    }
}
---
namespace menushell.Views
{
    public class MenuView : menushellView
    {
        public override void Display()

        {
            ClearPreviousView();

            Console.WriteLine("This is the main menu. Pick an option...");
            Console.WriteLine("F1. Login as user");
            Console.WriteLine("F2. Create new user");
            Console.WriteLine("F3. Search user");

            var input = Console.ReadKey();
            menushellView view;
            switch (input.Key)
            {
                case ConsoleKey.F1:
                    view = new LoginView();
                    break;
                case ConsoleKey.F2:
                    view = new CreateUserView();
                    break;
                case ConsoleKey.F3:
                    view = new SearchUserView();
                    break;
                default:
                    Display();
                    return;
            }
            view.Display();
        }
    }
}
----
using System;
using System.Collections.Generic;
using System.Linq;
using System.Security.Cryptography.X509Certificates;
using System.Text;
using System.Threading;
using menushell.Data;
using menushell.Models;

namespace menushell.Views
{

    public class SearchUserView : menushellView
    {
        private List<User> users = new List<User>();

        public override void Display()
        {
            // Provide output

            //Modify users

            Print(users); // Print all users
        }

        public override void Print(List<User> users)
        {
            foreach (var user in users)
            {
                Console.WriteLine(user.Name);
            }
        }


        private void SearchUser(int id)
        {
            users.First(x =>
                x.ID == id); // Finds users based on id, this will work for names but id                 provides a faster look up
        }

        private void DeleteUser(int id)
        {
            users.RemoveAll(x =>
                x.ID == id); // Removes users based on id, this will work for names but id                 provides a faster look up
        }
    }
}
---
namespace menushell
{
    class Program
    {
        private static menushellView _view;

        public static User CurrentUser;

        static void Main(string[] args)
        {
            _view = new MenuView();
            _view.Display();
        }


    }
}