public void ConfirmInvitationInProject(int invitationId)
{
var invitation = this.projectRepository.GetInvitationById(invitationId);
var projectId = invitation.ProjectId;
var receiverId = invitation.ReceiverId;
var user = this.userRepository.GetById(receiverId);
user.UserProjects.Add(this.projectRepository.GetById(projectId));
this.userRepository.UpdateUser(user);
var project = this.projectRepository.GetById(projectId);
project.ProjectUsers.Add(this.userRepository.GetById(receiverId));
this.projectRepository.Update(project);
invitation.IsInvitationConfirmed = true;
this.projectRepository.UpdateInvitation(invitation);
}