CompleteCommand.cs

    public class CompleteTodoCommand : IRequest<bool>
    {
        public Guid Id { get; set; }
    }
    
    public class CompleteTodoCommandHadler : IRequestHandler<CompleteTodoCommand, bool>
    {
        private readonly TodoDbContext _context;
        public CompleteTodoCommandHadler(TodoDbContext context)
        {
            this._context = context;
        }
        public async Task<bool> Handle(CompleteTodoCommand request, CancellationToken cancellationToken)
        {
            var todo = await _context.Todoes.FindAsync(request.Id);
            todo.Completed = true;
            _context.Todoes.Update(todo);

            var summary = await _context.TodoSummaries.Where(x => x.Date == DateTime.Today).FirstOrDefaultAsync();
            if (summary == null)
            {

                summary = new TodoSummary { Date = DateTime.Today, CompletedCount = 1 };
                _context.TodoSummaries.Add(summary);
            }
            else
            {
                summary.CompletedCount += 1;
                _context.TodoSummaries.Update(summary);
            }

            await _context.SaveChangesAsync();
            return true;
        }
    }