/*
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    * 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.
   * ====================================================================
   *
   * This software consists of voluntary contributions made by many
   * individuals on behalf of the Apache Software Foundation.  For more
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  package org.apache.http.impl.client.cache;
  
  import static org.mockito.Mockito.mock;
  import static org.mockito.Mockito.verify;
  import static org.mockito.Mockito.when;
  
  import org.apache.http.HttpHost;
  import org.apache.http.client.methods.HttpRequestWrapper;
  import org.apache.http.client.protocol.HttpClientContext;
  import org.apache.http.conn.routing.HttpRoute;
  import org.apache.http.impl.execchain.ClientExecChain;
  import org.apache.http.message.BasicHttpRequest;
  import org.junit.Before;
  import org.junit.Test;
  
  import java.util.concurrent.ScheduledExecutorService;
  import java.util.concurrent.TimeUnit;
  
  public class TestExponentialBackingOffSchedulingStrategy {
  
      private ScheduledExecutorService mockExecutor;
      private ExponentialBackOffSchedulingStrategy impl;
  
      @Before
      public void setUp() {
          mockExecutor = mock(ScheduledExecutorService.class);
  
          impl = new ExponentialBackOffSchedulingStrategy(
                  mockExecutor,
                  ExponentialBackOffSchedulingStrategy.DEFAULT_BACK_OFF_RATE,
                  ExponentialBackOffSchedulingStrategy.DEFAULT_INITIAL_EXPIRY_IN_MILLIS,
                  ExponentialBackOffSchedulingStrategy.DEFAULT_MAX_EXPIRY_IN_MILLIS
          );
      }
  
      @Test
      public void testScheduleWithoutPreviousError() {
          final AsynchronousValidationRequest request = createAsynchronousValidationRequest(withErrorCount(0));
  
          expectRequestScheduledWithoutDelay(request);
  
          impl.schedule(request);
  
          verify(mockExecutor).schedule(request, 0, TimeUnit.MILLISECONDS);
      }
  
      @Test
      public void testScheduleWithOneFailedAttempt() {
          final AsynchronousValidationRequest request = createAsynchronousValidationRequest(withErrorCount(1));
  
          expectRequestScheduledWithDelay(request, TimeUnit.SECONDS.toMillis(6));
  
          impl.schedule(request);
  
          verify(mockExecutor).schedule(request, 6000, TimeUnit.MILLISECONDS);
      }
  
      @Test
      public void testScheduleWithTwoFailedAttempts() {
          final AsynchronousValidationRequest request = createAsynchronousValidationRequest(withErrorCount(2));
  
          expectRequestScheduledWithDelay(request, TimeUnit.SECONDS.toMillis(60));
  
          impl.schedule(request);
  
          verify(mockExecutor).schedule(request, 60000, TimeUnit.MILLISECONDS);
      }
  
      @Test
      public void testScheduleWithThreeFailedAttempts() {
          final AsynchronousValidationRequest request = createAsynchronousValidationRequest(withErrorCount(3));
  
          expectRequestScheduledWithDelay(request, TimeUnit.SECONDS.toMillis(600));
 
         impl.schedule(request);
 
         verify(mockExecutor).schedule(request, 600000, TimeUnit.MILLISECONDS);
     }
 
     @Test
     public void testScheduleWithFourFailedAttempts() {
         final AsynchronousValidationRequest request = createAsynchronousValidationRequest(withErrorCount(4));
 
         expectRequestScheduledWithDelay(request, TimeUnit.SECONDS.toMillis(6000));
 
         impl.schedule(request);
 
         verify(mockExecutor).schedule(request, 6000000, TimeUnit.MILLISECONDS);
     }
 
     @Test
     public void testScheduleWithFiveFailedAttempts() {
         final AsynchronousValidationRequest request = createAsynchronousValidationRequest(withErrorCount(5));
 
         expectRequestScheduledWithDelay(request, TimeUnit.SECONDS.toMillis(60000));
 
         impl.schedule(request);
 
         verify(mockExecutor).schedule(request, 60000000, TimeUnit.MILLISECONDS);
     }
 
     @Test
     public void testScheduleWithSixFailedAttempts() {
         final AsynchronousValidationRequest request = createAsynchronousValidationRequest(withErrorCount(6));
 
         expectRequestScheduledWithDelay(request, TimeUnit.SECONDS.toMillis(86400));
 
         impl.schedule(request);
 
         verify(mockExecutor).schedule(request, 86400000, TimeUnit.MILLISECONDS);
     }
 
     @Test
     public void testScheduleWithMaxNumberOfFailedAttempts() {
         final AsynchronousValidationRequest request = createAsynchronousValidationRequest(withErrorCount(Integer.MAX_VALUE));
 
         expectRequestScheduledWithDelay(request, TimeUnit.SECONDS.toMillis(86400));
 
         impl.schedule(request);
 
         verify(mockExecutor).schedule(request, 86400000, TimeUnit.MILLISECONDS);
     }
 
     private void expectRequestScheduledWithoutDelay(final AsynchronousValidationRequest request) {
         expectRequestScheduledWithDelay(request, 0);
     }
 
     private void expectRequestScheduledWithDelay(final AsynchronousValidationRequest request, final long delayInMillis) {
         when(mockExecutor.schedule(request, delayInMillis, TimeUnit.MILLISECONDS)).thenReturn(null);
     }
 
     private AsynchronousValidationRequest createAsynchronousValidationRequest(final int errorCount) {
         final ClientExecChain clientExecChain = mock(ClientExecChain.class);
         final CachingExec cachingHttpClient = new CachingExec(clientExecChain);
         final AsynchronousValidator mockValidator = new AsynchronousValidator(impl);
         final HttpRoute httpRoute = new HttpRoute(new HttpHost("foo.example.com", 80));
         final HttpRequestWrapper httpRequestWrapper = HttpRequestWrapper.wrap(new BasicHttpRequest("GET", "/"));
         final HttpClientContext httpClientContext = new HttpClientContext();
         return new AsynchronousValidationRequest(mockValidator, cachingHttpClient, httpRoute, httpRequestWrapper,
                 httpClientContext, null, null, "identifier", errorCount);
     }
 
     private static int withErrorCount(final int errorCount) {
         return errorCount;
     }
 }