/*
    * 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.
   */
  package org.apache.commons.configuration2.reloading;
  
  import static org.junit.jupiter.api.Assertions.assertFalse;
  import static org.junit.jupiter.api.Assertions.assertIterableEquals;
  import static org.junit.jupiter.api.Assertions.assertThrows;
  import static org.junit.jupiter.api.Assertions.assertTrue;
  import static org.mockito.Mockito.mock;
  import static org.mockito.Mockito.verify;
  import static org.mockito.Mockito.verifyNoMoreInteractions;
  import static org.mockito.Mockito.when;
  
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.Collection;
  import java.util.List;
  
  import org.junit.jupiter.api.Test;
  
  /**
   * Test class for {@code CombinedReloadingController}.
   */
  public class TestCombinedReloadingController {
      /** An array with mock objects for the sub controllers. */
      private ReloadingController[] subControllers;
  
      /**
       * Creates an array with mock objects for sub controllers.
       */
      private void initSubControllers() {
          subControllers = new ReloadingController[3];
          for (int i = 0; i < subControllers.length; i++) {
              subControllers[i] = mock(ReloadingController.class);
          }
      }
  
      /**
       * Creates a test instance with default settings.
       *
       * @return the test instance
       */
      private CombinedReloadingController setUpController() {
          initSubControllers();
          final List<ReloadingController> lstCtrls = new ArrayList<>(Arrays.asList(subControllers));
          final CombinedReloadingController result = new CombinedReloadingController(lstCtrls);
          // check whether a defensive copy is created
          lstCtrls.clear();
          return result;
      }
  
      /**
       * Tests a check for a reloading operation which results in false.
       */
      @Test
      public void testCheckForReloadingFalse() {
          final CombinedReloadingController ctrl = setUpController();
  
          for (final ReloadingController rc : subControllers) {
              when(rc.checkForReloading(null)).thenReturn(Boolean.FALSE);
          }
  
          assertFalse(ctrl.checkForReloading("someParam"));
  
          for (final ReloadingController rc : subControllers) {
              verify(rc).checkForReloading(null);
              verifyNoMoreInteractions(rc);
          }
      }
  
      /**
       * Tests a check for a reloading operation which results in true.
       */
      @Test
      public void testCheckForReloadingTrue() {
          final CombinedReloadingController ctrl = setUpController();
  
          when(subControllers[0].checkForReloading(null)).thenReturn(Boolean.FALSE);
          when(subControllers[1].checkForReloading(null)).thenReturn(Boolean.TRUE);
          when(subControllers[2].checkForReloading(null)).thenReturn(Boolean.FALSE);
  
          assertTrue(ctrl.checkForReloading("someData"));
  
          for (final ReloadingController rc : subControllers) {
              verify(rc).checkForReloading(null);
             verifyNoMoreInteractions(rc);
         }
     }
 
     /**
      * Tests whether the sub controllers can be accessed.
      */
     @Test
     public void testGetSubControllers() {
         final CombinedReloadingController ctrl = setUpController();
         final Collection<ReloadingController> subs = ctrl.getSubControllers();
         assertIterableEquals(Arrays.asList(subControllers), subs);
     }
 
     /**
      * Tests that the list of sub controllers cannot be manipulated.
      */
     @Test
     public void testGetSubControllersModify() {
         final Collection<ReloadingController> subs = setUpController().getSubControllers();
         assertThrows(UnsupportedOperationException.class, subs::clear);
     }
 
     /**
      * Tries to create an instance without a collection.
      */
     @Test
     public void testInitNull() {
         assertThrows(IllegalArgumentException.class, () -> new CombinedReloadingController(null));
     }
 
     /**
      * Tries to create an instance with a collection containing a null entry.
      */
     @Test
     public void testInitNullEntries() {
         initSubControllers();
         final Collection<ReloadingController> ctrls = new ArrayList<>(Arrays.asList(subControllers));
         ctrls.add(null);
         assertThrows(IllegalArgumentException.class, () -> new CombinedReloadingController(ctrls));
     }
 
     /**
      * Tests whether the sub controller's reloading state can be reset unconditionally.
      */
     @Test
     public void testResetInitialReloadingState() {
         final CombinedReloadingController ctrl = setUpController();
         ctrl.resetInitialReloadingState();
 
         for (final ReloadingController rc : subControllers) {
             verify(rc).resetReloadingState();
             verifyNoMoreInteractions(rc);
         }
     }
 
     /**
      * Tests whether the reloading state can be reset.
      */
     @Test
     public void testResetReloadingState() {
         final CombinedReloadingController ctrl = setUpController();
 
         when(subControllers[0].checkForReloading(null)).thenReturn(Boolean.TRUE);
         when(subControllers[1].checkForReloading(null)).thenReturn(Boolean.FALSE);
         when(subControllers[2].checkForReloading(null)).thenReturn(Boolean.FALSE);
 
         ctrl.checkForReloading(null);
         ctrl.resetReloadingState();
 
         for (final ReloadingController rc : subControllers) {
             verify(rc).checkForReloading(null);
             verify(rc).resetReloadingState();
             verifyNoMoreInteractions(rc);
         }
     }
 }