Demo/Program.cs

using Posechaemost.Data.Repository;
using Posechaemost.Domain.UseCase;
using Posechaemost.UI;
using Microsoft.Extensions.DependencyInjection;
using System.Text.RegularExpressions;

IServiceCollection services = new ServiceCollection();

services
    .AddSingleton<IGroupRepository, SQLGroupRepositoryImpl>()
    .AddSingleton<IUserRepository, SQLUserRepositoryImpl>()
    .AddSingleton<IPresenceRepository, SQLPresenceRepositoryImpl>()
    .AddSingleton<UserUseCase>()
    .AddSingleton<GroupUseCase>()
    .AddSingleton<PresenceUseCase>();

var serviceProvider = services.BuildServiceProvider();

var userUseCase = serviceProvider.GetService<UserUseCase>();
var groupUseCase = serviceProvider.GetService<GroupUseCase>();
var presenceUseCase = serviceProvider.GetService<PresenceUseCase>();

MainMenuUI mainMenuUI = new MainMenuUI(userUseCase, groupUseCase, presenceUseCase);