package emissary.grpc.exceptions;
   
   import io.grpc.Status;
   import io.grpc.StatusRuntimeException;
   import org.apache.commons.lang3.StringUtils;
   
   /**
    * Encapsulates bad data errors related to an external service. These errors should be treated as unrecoverable and
    * should not be made due to temporal server state.
   */
  public class ServiceException extends RuntimeException {
  
      private static final long serialVersionUID = 1371863576664142288L;
  
      public static final String GRPC_ERROR_PREFIX = "Encountered gRPC runtime status error. ";
  
      public ServiceException(String errorMessage) {
          super(errorMessage);
      }
  
      public ServiceException(String errorMessage, Throwable err) {
          super(errorMessage, err);
      }
  
      public static void handleGrpcStatusRuntimeException(StatusRuntimeException e) {
          if (e == null) {
              throw new ServiceException("Service returned a null exception");
          }
          Status status = e.getStatus();
          if (status == null) {
              throw new ServiceException("Service returned a null status: " + e.getMessage(), e);
          }
          // code shouldn't ever be null, but we check for safety
          Status.Code code = status.getCode();
          if (code == null) {
              throw new ServiceException("Service returned a status with a null code: " + e.getMessage(), e);
          }
  
          switch (code) {
              case DEADLINE_EXCEEDED:
                  throw new ServiceException(GRPC_ERROR_PREFIX + "gRPC client connection has timed out: " + e.getMessage(), e);
              case UNAVAILABLE: {
                  // Likely server has gone down. Could be a crash or resources were scaled down
                  String desc = status.getDescription();
                  if (StringUtils.isNotEmpty(desc) && desc.contains("Network closed for unknown reason")) {
                      // So-called "poison pill" files have resulted in crashes for unknown reasons.
                      // Out of an abundance of caution, we consider these files as failures.
                      throw new ServiceException(GRPC_ERROR_PREFIX +
                              "It's possible service crashed due to a misbehaving file: " + e.getMessage(), e);
                  }
                  // Otherwise, we indicate the server is not live
                  throw new ServiceNotLiveException(GRPC_ERROR_PREFIX + "It's likely service crashed: " + e.getMessage(), e);
              }
              case CANCELLED:
                  throw new ServiceException(GRPC_ERROR_PREFIX + "It's likely a client side interrupt occurred: " + e.getMessage(), e);
              case RESOURCE_EXHAUSTED:
                  // Likely we've exceeded the maximum number of concurrent requests
                  throw new ServiceNotReadyException(GRPC_ERROR_PREFIX +
                          "It's likely we've exceeded the maximum number of requests: " + e.getMessage(), e);
              case INTERNAL:
                  // Likely server killed itself due to OOM or other conditions
                  throw new ServiceException(GRPC_ERROR_PREFIX +
                          "It's likely a gpu OOM error or other resource error has occurred: " + e.getMessage(), e);
              default:
                  throw new ServiceException(GRPC_ERROR_PREFIX +
                          "This is an unhandled code type. Please add it to the list of gRPC exceptions: " + e.getMessage(), e);
          }
      }
  }