package org.jboss.resteasy.client.jaxrs;

import java.util.concurrent.CompletableFuture;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Future;

import javax.ws.rs.client.InvocationCallback;

import org.jboss.resteasy.client.jaxrs.internal.ClientInvocation;
import org.jboss.resteasy.client.jaxrs.internal.ClientResponse;

/**
 * Interface for an async HttpClientEngine
 *
 * @author Markus Kull
 */
public interface AsyncClientHttpEngine extends ClientHttpEngine
{

   /**
    * Interface for extracting a result out of a ClientResponse
    *
    * @param <T> Result-Type
    */
   public interface ResultExtractor<T>
   {
      /**
       * Extracts a result out of a Response
       *
       * @param response Response
       * @return result
       */
      T extractResult(ClientResponse response);
   }

   /**
    * Submits an asynchronous request.
    *
    * @param <T> type
    * @param request Request
    * @param buffered buffer the response?
    * @param callback Optional callback receiving the result, which is run inside the io-thread. may be null.
    * @param extractor ResultExtractor for extracting a result out of a ClientResponse. Is run inside the io-thread
    * @return Future with the result or Exception
    */
   <T> Future<T> submit(ClientInvocation request, boolean buffered, InvocationCallback<T> callback, ResultExtractor<T> extractor);

   /**
    * Submits an asynchronous request.
    *
    * @param <T> type
    * @param request Request
    * @param buffered buffer the response?
    * @param extractor ResultExtractor for extracting a result out of a ClientResponse. Is run inside the io-thread
    * @return {@link CompletableFuture} with the result or Exception
    */
   default <T> CompletableFuture<T> submit(ClientInvocation request, boolean buffered, ResultExtractor<T> extractor)
   {
      return submit(request, buffered, extractor, null);
   }

   /**
    * Submits an asynchronous request.
    *
    * @param <T> type
    * @param request Request
    * @param buffered buffer the response?
    * @param extractor ResultExtractor for extracting a result out of a ClientResponse. Is run inside the io-thread
    * @param executorService the executor to use for asynchronous execution
    * @return {@link CompletableFuture} with the result or Exception
    */
   <T> CompletableFuture<T> submit(ClientInvocation request, boolean buffered, ResultExtractor<T> extractor,
                                   ExecutorService executorService);

}
