package usecase.auth;
   
   import model.entity.User;
   import model.repository.GenericRepository;
   
   import javax.enterprise.context.RequestScoped;
   import javax.enterprise.context.SessionScoped;
   import javax.enterprise.inject.Produces;
   import javax.inject.Inject;
  import javax.inject.Named;
  import javax.transaction.Transactional;
  import java.io.Serializable;
  import java.time.Instant;
  
  /**
   * Classe che fornisce i servizi relativi all'autenticazione.
   */
  @SessionScoped
  @Transactional
  public class AuthenticationService implements Serializable {
      private GenericRepository genericRepository;
      private Pbkdf2PasswordHash passwordHash;
      private int currentUserId = 0;
  
      protected AuthenticationService(){}
  
      @Inject
      protected AuthenticationService(GenericRepository genericRepository,
                                      Pbkdf2PasswordHash passwordHash){
          this.genericRepository = genericRepository;
          this.passwordHash = passwordHash;
      }
  
  
      /**
       * Autentica un utente
       * @param username stringa con nome utente
       * @param password stringa con password
       * @return esito dell'operazione
       */
      public boolean authenticate(String username, String password){
          User user = genericRepository.findByNaturalId(User.class,username);
          if(user == null)
              return false;
          if (passwordHash.verify(password, user.getPassword(), user.getSalt())){
              currentUserId = user.getId();
              return true;
          } else {
              return false;
          }
      }
  
      /**
       * Ritorna l'utente in uso e ne rende accessibile i dati nelle jsp
       * @return utente in uso
       */
      @Named("currentUser") //accessibile nelle jsp con ${currentUser}
      @RequestScoped
      @Produces
      public CurrentUser getCurrentUser(){
          if(currentUserId <= 0)
              return new CurrentUser();
  
          User user = genericRepository.findById(User.class,currentUserId);
          if(user == null)
              return new CurrentUser();
  
          Instant longestCurrentBan = user.getBans().isEmpty() ? null : user.getBans().get(0).getEndTime();
  
          CurrentUser currentUser = CurrentUser.builder()
                  .username(user.getUsername())
                  .id(user.getId())
                  .isAdmin(user.getAdmin())
                  .picture(user.getPicture())
                  .banDuration(longestCurrentBan)
                  .isLoggedIn(true)
                  .build();
  
          System.out.println(currentUser);
          return currentUser;
      }
  
  }