/*
    * Copyright 2018 LINE Corporation
    *
    * LINE Corporation 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:
    *
    *   https://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 com.linecorp.centraldogma.client.armeria.legacy;
  
  import java.net.UnknownHostException;
  import java.util.concurrent.ScheduledExecutorService;
  
  import com.linecorp.armeria.client.ClientBuilder;
  import com.linecorp.armeria.client.ClientRequestContext;
  import com.linecorp.armeria.client.encoding.DecodingClient;
  import com.linecorp.armeria.client.endpoint.EndpointGroup;
  import com.linecorp.armeria.common.HttpHeaderNames;
  import com.linecorp.armeria.common.HttpRequest;
  import com.linecorp.centraldogma.client.CentralDogma;
  import com.linecorp.centraldogma.client.armeria.AbstractArmeriaCentralDogmaBuilder;
  import com.linecorp.centraldogma.client.armeria.ArmeriaCentralDogmaBuilder;
  import com.linecorp.centraldogma.internal.client.ReplicationLagTolerantCentralDogma;
  import com.linecorp.centraldogma.internal.thrift.CentralDogmaService.AsyncIface;
  
  /**
   * Builds a legacy {@link CentralDogma} client based on Thrift.
   *
   * @deprecated Use {@link ArmeriaCentralDogmaBuilder}.
   */
  @Deprecated
  public class LegacyCentralDogmaBuilder extends AbstractArmeriaCentralDogmaBuilder<LegacyCentralDogmaBuilder> {
      /**
       * Returns a newly-created {@link CentralDogma} instance.
       *
       * @throws UnknownHostException if failed to resolve the host names from the DNS servers
       */
      public CentralDogma build() throws UnknownHostException {
          final EndpointGroup endpointGroup = endpointGroup();
          final String scheme = "tbinary+" + (isUseTls() ? "https" : "http");
          final ClientBuilder builder =
                  newClientBuilder(scheme, endpointGroup, cb -> {
                      cb.decorator(DecodingClient.newDecorator())
                        .rpcDecorator(LegacyCentralDogmaTimeoutScheduler::new);
                  }, "/cd/thrift/v1");
  
          final String authorization = "Bearer " + accessToken();
          builder.decorator((delegate, ctx, req) -> {
              if (!req.headers().contains(HttpHeaderNames.AUTHORIZATION)) {
                  // To prevent CSRF attack, we add 'Authorization' header to every request.
                  final HttpRequest newReq = req.withHeaders(req.headers()
                                                                .toBuilder()
                                                                .set(HttpHeaderNames.AUTHORIZATION, authorization)
                                                                .build());
                  return delegate.execute(ctx, newReq);
              }
              return delegate.execute(ctx, req);
          });
  
          final ScheduledExecutorService blockingTaskExecutor = blockingTaskExecutor();
  
          final int maxRetriesOnReplicationLag = maxNumRetriesOnReplicationLag();
          final CentralDogma dogma = new LegacyCentralDogma(blockingTaskExecutor,
                                                            builder.build(AsyncIface.class), endpointGroup);
          if (maxRetriesOnReplicationLag <= 0) {
              return dogma;
          } else {
              return new ReplicationLagTolerantCentralDogma(
                      blockingTaskExecutor, dogma, maxRetriesOnReplicationLag,
                      retryIntervalOnReplicationLagMillis(),
                      () -> {
                          // FIXME(trustin): Note that this will always return `null` due to a known limitation
                          //                 in Armeria: https://github.com/line/armeria/issues/760
                          final ClientRequestContext ctx = ClientRequestContext.currentOrNull();
                          return ctx != null ? ctx.remoteAddress() : null;
                      });
          }
      }
  }