package fr.tiogars.inception.domains.auth.role.services;
   
   import java.time.Clock;
   import java.time.Instant;
   import java.time.temporal.ChronoUnit;
   import java.util.List;
   import java.util.Optional;
   import java.util.Set;
   
  import org.springframework.beans.factory.annotation.Autowired;
  import org.springframework.stereotype.Service;
  import org.springframework.transaction.annotation.Transactional;
  
  import fr.tiogars.inception.domains.auth.role.entities.Role;
  import fr.tiogars.inception.domains.auth.role.entities.RoleEntity;
  import fr.tiogars.inception.domains.auth.role.models.CreateRoleRequest;
  import fr.tiogars.inception.domains.auth.role.models.UpdateRoleRequest;
  import fr.tiogars.inception.domains.auth.role.repositories.RoleRepository;
  
  /** Coordinates role persistence and default role seeding. */
  @Service
  public class RoleService {
  
      public static final String ANONYMOUS = "ANONYMOUS";
      public static final String ADMIN = "ADMIN";
      public static final String USER = "USER";
  
      private static final Set<String> SYSTEM_ROLES = Set.of(ANONYMOUS, ADMIN, USER);
  
      private final Clock clock;
      private final RoleRepository repository;
  
      @Autowired
      public RoleService(RoleRepository repository) {
          this(repository, Clock.systemUTC());
      }
  
      RoleService(RoleRepository repository, Clock clock) {
          this.repository = repository;
          this.clock = clock;
      }
  
      @Transactional
      public Optional<Role> create(CreateRoleRequest request) {
          if (repository.findByCode(request.code()).isPresent()) {
              return Optional.empty();
          }
          Instant timestamp = currentTimestamp();
          return Optional.of(toRecord(repository.save(new RoleEntity(request.code(), request.label(), timestamp, timestamp))));
      }
  
      @Transactional
      public Optional<Role> update(Long id, UpdateRoleRequest request) {
          return repository.findById(id)
                  .map(existing -> {
                      existing.update(request.label(), currentTimestamp());
                      return toRecord(repository.save(existing));
                  });
      }
  
      @Transactional
      public boolean delete(Long id) {
          return repository.findById(id)
                  .filter(existing -> !SYSTEM_ROLES.contains(existing.getCode()))
                  .map(existing -> {
                      repository.delete(existing);
                      return true;
                  })
                  .orElse(false);
      }
  
      public List<Role> findAll() {
          return repository.findAllByOrderByCodeAsc().stream()
                  .map(RoleService::toRecord)
                  .toList();
      }
  
      public Optional<Role> findById(Long id) {
          return repository.findById(id).map(RoleService::toRecord);
      }
  
      public Optional<RoleEntity> findEntityByCode(String code) {
          return repository.findByCode(code);
      }
  
      @Transactional
      public List<Role> seedDefaultRoles() {
          return List.of(
                  seedSystemRole(ANONYMOUS, "Anonymous"),
                  seedSystemRole(ADMIN, "Administrator"),
                  seedSystemRole(USER, "User"));
      }
  
      private Role seedSystemRole(String code, String label) {
          Instant timestamp = currentTimestamp();
          RoleEntity entity = repository.findByCode(code)
                  .map(existing -> {
                      existing.update(label, timestamp);
                      return existing;
                 })
                 .orElseGet(() -> new RoleEntity(code, label, timestamp, timestamp));
         return toRecord(repository.save(entity));
     }
 
     private Instant currentTimestamp() {
         return Instant.now(clock).truncatedTo(ChronoUnit.MICROS);
     }
 
     public static Role toRecord(RoleEntity entity) {
         return new Role(entity.getId(), entity.getCode(), entity.getLabel(), entity.getCreatedDate(), entity.getLastModifiedDate());
     }
 }