/*
    * 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.builder;
  
  import static org.junit.jupiter.api.Assertions.assertEquals;
  import static org.junit.jupiter.api.Assertions.assertFalse;
  import static org.junit.jupiter.api.Assertions.assertNull;
  import static org.junit.jupiter.api.Assertions.assertSame;
  import static org.junit.jupiter.api.Assertions.assertThrows;
  import static org.mockito.Mockito.mock;
  
  import java.nio.charset.StandardCharsets;
  import java.util.Map;
  
  import org.apache.commons.configuration2.builder.fluent.FileBasedBuilderParameters;
  import org.apache.commons.configuration2.builder.fluent.Parameters;
  import org.apache.commons.configuration2.builder.fluent.PropertiesBuilderParameters;
  import org.apache.commons.configuration2.builder.fluent.XMLBuilderParameters;
  import org.apache.commons.configuration2.convert.ListDelimiterHandler;
  import org.apache.commons.configuration2.tree.ExpressionEngine;
  import org.junit.jupiter.api.BeforeAll;
  import org.junit.jupiter.api.BeforeEach;
  import org.junit.jupiter.api.Test;
  
  /**
   * Test class for {@code DefaultParametersManager}.
   */
  public class TestDefaultParametersManager {
      /**
       * A test defaults handler implementation for testing the initialization of parameters objects with default values. This
       * class sets some hard-coded default values.
       */
      private static final class FileBasedDefaultsHandler implements DefaultParametersHandler<FileBasedBuilderParameters> {
          @Override
          public void initializeDefaults(final FileBasedBuilderParameters parameters) {
              parameters.setThrowExceptionOnMissing(true).setEncoding(DEF_ENCODING).setListDelimiterHandler(listHandler);
          }
      }
  
      /** Constant for the default encoding. */
      private static final String DEF_ENCODING = StandardCharsets.UTF_8.name();
  
      /** A test list delimiter handler. */
      private static ListDelimiterHandler listHandler;
  
      /**
       * Checks whether the expected default values have been set on a parameters object.
       *
       * @param map the map with parameters
       */
      private static void checkDefaultValues(final Map<String, Object> map) {
          assertEquals(listHandler, map.get("listDelimiterHandler"));
          assertEquals(Boolean.TRUE, map.get("throwExceptionOnMissing"));
          final FileBasedBuilderParametersImpl fbparams = FileBasedBuilderParametersImpl.fromParameters(map);
          assertEquals(DEF_ENCODING, fbparams.getFileHandler().getEncoding());
      }
  
      /**
       * Checks that no default values have been set on a parameters object.
       *
       * @param map the map with parameters
       */
      private static void checkNoDefaultValues(final Map<String, Object> map) {
          assertFalse(map.containsKey("throwExceptionOnMissing"));
          final FileBasedBuilderParametersImpl fbParams = FileBasedBuilderParametersImpl.fromParameters(map, true);
          assertNull(fbParams.getFileHandler().getEncoding());
      }
  
      @BeforeAll
      public static void setUpBeforeClass() throws Exception {
          listHandler = mock(ListDelimiterHandler.class);
      }
  
      /** An object for creating new parameters objects. */
      private Parameters parameters;
  
      /** The manager to be tested. */
      private DefaultParametersManager manager;
  
      @BeforeEach
      public void setUp() throws Exception {
          parameters = new Parameters();
          manager = new DefaultParametersManager();
      }
  
     /**
      * Tests whether default values are set for newly created parameters objects.
      */
     @Test
     public void testApplyDefaults() {
         manager.registerDefaultsHandler(FileBasedBuilderParameters.class, new FileBasedDefaultsHandler());
         final FileBasedBuilderParameters params = parameters.fileBased();
         manager.initializeParameters(params);
         final Map<String, Object> map = params.getParameters();
         checkDefaultValues(map);
     }
 
     /**
      * Tests whether multiple handlers can be registered for the same classes and whether they are called in the correct
      * order.
      */
     @Test
     public void testApplyDefaultsMultipleHandlers() {
         final ExpressionEngine engine = mock(ExpressionEngine.class);
         manager.registerDefaultsHandler(XMLBuilderParameters.class, parameters -> parameters.setThrowExceptionOnMissing(false)
             .setListDelimiterHandler(mock(ListDelimiterHandler.class)).setExpressionEngine(engine));
         manager.registerDefaultsHandler(FileBasedBuilderParameters.class, new FileBasedDefaultsHandler());
         final XMLBuilderParameters params = parameters.xml();
         manager.initializeParameters(params);
         final Map<String, Object> map = params.getParameters();
         checkDefaultValues(map);
         assertSame(engine, map.get("expressionEngine"));
     }
 
     /**
      * Tests whether default values are also applied when a sub parameters class is created.
      */
     @Test
     public void testApplyDefaultsOnSubClass() {
         manager.registerDefaultsHandler(FileBasedBuilderParameters.class, new FileBasedDefaultsHandler());
         final XMLBuilderParameters params = parameters.xml();
         manager.initializeParameters(params);
         final Map<String, Object> map = params.getParameters();
         checkDefaultValues(map);
     }
 
     /**
      * Tests that default values are only applied if the start class provided at registration time matches.
      */
     @Test
     public void testApplyDefaultsStartClass() {
         manager.registerDefaultsHandler(FileBasedBuilderParameters.class, new FileBasedDefaultsHandler(), XMLBuilderParameters.class);
         final XMLBuilderParameters paramsXml = parameters.xml();
         manager.initializeParameters(paramsXml);
         Map<String, Object> map = paramsXml.getParameters();
         checkDefaultValues(map);
         final PropertiesBuilderParameters paramsProps = parameters.properties();
         manager.initializeParameters(paramsProps);
         map = paramsProps.getParameters();
         checkNoDefaultValues(map);
     }
 
     /**
      * Tests whether initializeParameters() ignores null input. (We can only test that no exception is thrown.)
      */
     @Test
     public void testInitializeParametersNull() {
         manager.registerDefaultsHandler(FileBasedBuilderParameters.class, new FileBasedDefaultsHandler());
         manager.initializeParameters(null);
     }
 
     /**
      * Tries to register a default handler without a class.
      */
     @Test
     public void testRegisterDefaultsHandlerNoClass() {
         final FileBasedDefaultsHandler handler = new FileBasedDefaultsHandler();
         assertThrows(IllegalArgumentException.class, () -> manager.registerDefaultsHandler(null, handler));
     }
 
     /**
      * Tries to register a null default handler.
      */
     @Test
     public void testRegisterDefaultsHandlerNoHandler() {
         assertThrows(IllegalArgumentException.class, () -> manager.registerDefaultsHandler(BasicBuilderProperties.class, null));
     }
 
     /**
      * Tests whether all occurrences of a given defaults handler can be removed.
      */
     @Test
     public void testUnregisterDefaultsHandlerAll() {
         final FileBasedDefaultsHandler handler = new FileBasedDefaultsHandler();
         manager.registerDefaultsHandler(FileBasedBuilderParameters.class, handler, XMLBuilderParameters.class);
         manager.registerDefaultsHandler(FileBasedBuilderParameters.class, handler, PropertiesBuilderParameters.class);
         manager.unregisterDefaultsHandler(handler);
 
         final XMLBuilderParameters paramsXml = parameters.xml();
         manager.initializeParameters(paramsXml);
         checkNoDefaultValues(paramsXml.getParameters());
         final PropertiesBuilderParameters paramsProps = parameters.properties();
         manager.initializeParameters(paramsProps);
         checkNoDefaultValues(paramsProps.getParameters());
     }
 
     /**
      * Tests whether a specific occurrence of a defaults handler can be removed.
      */
     @Test
     public void testUnregisterDefaultsHandlerSpecific() {
         final FileBasedDefaultsHandler handler = new FileBasedDefaultsHandler();
         manager.registerDefaultsHandler(FileBasedBuilderParameters.class, handler, XMLBuilderParameters.class);
         manager.registerDefaultsHandler(FileBasedBuilderParameters.class, handler, PropertiesBuilderParameters.class);
         manager.unregisterDefaultsHandler(handler, PropertiesBuilderParameters.class);
         final XMLBuilderParameters paramsXml = parameters.xml();
         manager.initializeParameters(paramsXml);
         checkDefaultValues(paramsXml.getParameters());
         final PropertiesBuilderParameters paramsProps = parameters.properties();
         manager.initializeParameters(paramsProps);
         checkNoDefaultValues(paramsProps.getParameters());
     }
 }