export class UpdateUserCommandHandler {
  constructor(userRepository) {
    this.userRepository = userRepository;
  }

  async handle(command) {
    const userData = {};
    if (command.name) userData.name = command.name;
    if (command.email) userData.email = command.email;
    if (command.age !== undefined) userData.age = command.age;
    
    const result = await this.userRepository.update(command.id, userData);
    if (!result) {
      throw new Error('User not found');
    }
    return result;
  }
}