/**
 * Licensed to jclouds, Inc. (jclouds) under one or more
 * contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  jclouds 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.jclouds.concurrent;

import static org.jclouds.util.Throwables2.propagateOrNull;
import static org.testng.Assert.assertEquals;

import java.util.concurrent.Callable;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;

import org.testng.annotations.Test;

import com.google.common.base.Function;
import com.google.common.base.Throwables;
import com.google.common.collect.Iterables;
import com.google.common.util.concurrent.ListenableFuture;

/**
 * Tests behavior of FutureExceptionParser
 * 
 * @author Adrian Cole
 */
@Test(groups = "unit")
public class FutureExceptionParserTest {
   ExecutorService executorService = MoreExecutors.sameThreadExecutor();

   @Test
   public void testGet() throws InterruptedException, ExecutionException {
      Future<?> future = createFuture(new RuntimeException("foo"));
      assertEquals(future.get(), "foo");
   }

   @Test(expectedExceptions = Exception.class)
   public void testGetUnmatched() throws InterruptedException, ExecutionException {
      Future<?> future = createFuture(new Exception("foo"));
      assertEquals(future.get(), "foo");
   }

   @Test
   public void testGetLongTimeUnit() throws InterruptedException, ExecutionException, TimeoutException {
      Future<?> future = createFuture(new RuntimeException("foo"));
      assertEquals(future.get(1, TimeUnit.SECONDS), "foo");
   }

   @Test(expectedExceptions = Exception.class)
   public void testGetLongTimeUnitUnmatched() throws InterruptedException, ExecutionException, TimeoutException {
      Future<?> future = createFuture(new Exception("foo"));
      assertEquals(future.get(1, TimeUnit.SECONDS), "foo");
   }

   @SuppressWarnings( { "unchecked", "rawtypes" })
   private Future<?> createFuture(final Exception exception) {
      ListenableFuture<?> future = Futures.makeListenable(executorService.submit(new Callable<String>() {

         public String call() throws Exception {
            throw exception;
         }

         @Override
         public String toString() {
            return "throwException(" + exception + ")";
         }
      }), executorService);

      future = new ExceptionParsingListenableFuture(future, new Function<Exception, String>() {

         public String apply(Exception from) {
            if (Iterables.size(Iterables.filter(Throwables.getCausalChain(from), RuntimeException.class)) >= 1)
               return from.getMessage();
            return String.class.cast(propagateOrNull(from));
         }

      });
      return future;
   }

}
