/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.servicecomb.transport.highway;

import java.util.concurrent.CompletableFuture;

import javax.annotation.Nonnull;

import org.apache.servicecomb.codec.protobuf.definition.OperationProtobuf;
import org.apache.servicecomb.codec.protobuf.definition.ProtobufManager;
import org.apache.servicecomb.core.Const;
import org.apache.servicecomb.core.Invocation;
import org.apache.servicecomb.core.exception.Exceptions;
import org.apache.servicecomb.core.filter.ConsumerFilter;
import org.apache.servicecomb.core.filter.Filter;
import org.apache.servicecomb.core.filter.FilterNode;
import org.apache.servicecomb.foundation.common.utils.AsyncUtils;
import org.apache.servicecomb.foundation.vertx.client.tcp.TcpData;
import org.apache.servicecomb.swagger.invocation.InvocationType;
import org.apache.servicecomb.swagger.invocation.Response;
import org.apache.servicecomb.swagger.invocation.exception.InvocationException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class HighwayClientFilter implements ConsumerFilter {
  private static final Logger LOGGER = LoggerFactory.getLogger(HighwayClientFilter.class);

  public static final String NAME = "highway-client";

  @Nonnull
  @Override
  public String getName() {
    return NAME;
  }

  @Override
  public boolean enabledForTransport(String transport) {
    return Const.HIGHWAY.equals(transport);
  }

  @Override
  public int getOrder(InvocationType invocationType, String application, String serviceName) {
    return Filter.CONSUMER_LOAD_BALANCE_ORDER + 2000;
  }

  @Override
  public CompletableFuture<Response> onFilter(Invocation invocation, FilterNode nextNode) {
    LOGGER.debug("Sending request by highway, operation={}, endpoint={}.",
        invocation.getMicroserviceQualifiedName(),
        invocation.getEndpoint().getEndpoint());

    OperationProtobuf operationProtobuf = ProtobufManager.getOrCreateOperation(invocation);
    return send(invocation, operationProtobuf)
        .thenApply(tcpData -> convertToResponse(invocation, operationProtobuf, tcpData))
        .thenApply(this::convertFailedResponseToException)
        .whenComplete((response, throwable) -> invocation.getInvocationStageTrace().finishClientFiltersResponse());
  }

  protected CompletableFuture<TcpData> send(Invocation invocation, OperationProtobuf operationProtobuf) {
    invocation.getInvocationStageTrace().startGetConnection();
    HighwayClient highwayClient = ((HighwayTransport) invocation.getTransport()).getHighwayClient();
    HighwayClientPackage clientPackage = highwayClient.createClientPackage(invocation, operationProtobuf);
    HighwayClientConnection clientConnection = highwayClient.findClientPool(invocation);
    invocation.getInvocationStageTrace().startClientFiltersRequest();
    invocation.onStartSendRequest();
    CompletableFuture<TcpData> sendFuture = clientConnection
        .send(clientPackage)
        .whenComplete((tcpData, throwable) -> afterSend(invocation, clientPackage));
    return invocation.optimizeSyncConsumerThread(sendFuture);
  }

  protected void afterSend(Invocation invocation, HighwayClientPackage clientPackage) {
    invocation.getInvocationStageTrace().finishWriteToBuffer(clientPackage.getFinishWriteToBuffer());
    invocation.getInvocationStageTrace().finishReceiveResponse();

    invocation.getInvocationStageTrace().startClientFiltersResponse();
  }

  protected Response convertToResponse(Invocation invocation, OperationProtobuf operationProtobuf, TcpData tcpData) {
    try {
      return HighwayCodec.decodeResponse(invocation, operationProtobuf, tcpData);
    } catch (Exception e) {
      throw AsyncUtils.rethrow(e);
    }
  }

  protected Response convertFailedResponseToException(Response response) {
    if (response.isFailed()) {
      Object errorData = response.getResult();
      if (errorData instanceof InvocationException) {
        errorData = ((InvocationException) errorData).getErrorData();
      }
      throw Exceptions.create(response.getStatus(), errorData);
    }

    return response;
  }
}
