package com.atlassian.httpclient.apache.httpcomponents;
   
   import com.atlassian.event.api.EventPublisher;
   import com.atlassian.httpclient.api.HttpClient;
   import com.atlassian.httpclient.api.factory.HttpClientFactory;
   import com.atlassian.httpclient.api.factory.HttpClientOptions;
   import com.atlassian.sal.api.ApplicationProperties;
   import com.atlassian.sal.api.executor.ThreadLocalContextManager;
   import com.google.common.annotations.VisibleForTesting;
  import org.springframework.beans.factory.DisposableBean;
  
  import javax.annotation.Nonnull;
  import java.util.Set;
  import java.util.concurrent.CopyOnWriteArraySet;
  
  import static com.google.common.base.Preconditions.checkNotNull;
  
  public final class DefaultHttpClientFactory<C> implements HttpClientFactory, DisposableBean {
      private final EventPublisher eventPublisher;
      private final ApplicationProperties applicationProperties;
      private final ThreadLocalContextManager<C> threadLocalContextManager;
      private final Set<ApacheAsyncHttpClient> httpClients = new CopyOnWriteArraySet<ApacheAsyncHttpClient>();
  
      public DefaultHttpClientFactory(
              @Nonnull EventPublisher eventPublisher,
              @Nonnull ApplicationProperties applicationProperties,
              @Nonnull ThreadLocalContextManager<C> threadLocalContextManager) {
          this.eventPublisher = checkNotNull(eventPublisher);
          this.applicationProperties = checkNotNull(applicationProperties);
          this.threadLocalContextManager = checkNotNull(threadLocalContextManager);
      }
  
      @Override
      @Nonnull
      public HttpClient create(@Nonnull HttpClientOptions options) {
          return doCreate(options, threadLocalContextManager);
      }
  
      @Override
      @Nonnull
      public <C> HttpClient create(@Nonnull HttpClientOptions options, @Nonnull ThreadLocalContextManager<C> threadLocalContextManager) {
          return doCreate(options, threadLocalContextManager);
      }
  
      @Override
      public void dispose(@Nonnull final HttpClient httpClient) throws Exception {
          if (httpClient instanceof ApacheAsyncHttpClient) {
              final ApacheAsyncHttpClient client = (ApacheAsyncHttpClient) httpClient;
              if (httpClients.remove(client)) {
                  client.destroy();
              } else {
                  throw new IllegalStateException("Client is already disposed");
              }
          } else {
              throw new IllegalArgumentException("Given client is not disposable");
          }
      }
  
      private <C> HttpClient doCreate(@Nonnull HttpClientOptions options, ThreadLocalContextManager<C> threadLocalContextManager) {
          checkNotNull(options);
          final ApacheAsyncHttpClient<C> httpClient = new ApacheAsyncHttpClient<>(eventPublisher, applicationProperties, threadLocalContextManager, options);
          httpClients.add(httpClient);
          return httpClient;
      }
  
      @Override
      public void destroy() throws Exception {
          for (ApacheAsyncHttpClient httpClient : httpClients) {
              httpClient.destroy();
          }
      }
  
      @VisibleForTesting
      @Nonnull
      Iterable<ApacheAsyncHttpClient> getHttpClients() {
          return httpClients;
      }
  }