package org.apache.onami.test.handler;
   
   /*
    * 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.
   */
  
  import java.lang.reflect.Field;
  import java.lang.reflect.Method;
  import java.lang.reflect.Modifier;
  import java.util.HashMap;
  import java.util.Map.Entry;
  import java.util.logging.Level;
  import java.util.logging.Logger;
  
  import org.apache.onami.test.annotation.Mock;
  import org.apache.onami.test.mock.MockEngine;
  import org.apache.onami.test.reflection.FieldHandler;
  import org.apache.onami.test.reflection.HandleException;
  
  /**
   * Handler class to handle all {@link Mock} annotations.
   *
   * @see org.apache.onami.test.reflection.ClassVisitor
   * @see Mock
   */
  public final class MockHandler
      implements FieldHandler<Mock>
  {
  
      private static final Logger LOGGER = Logger.getLogger( MockHandler.class.getName() );
  
      private final HashMap<Field, Object> mockedObjects = new HashMap<Field, Object>( 1 );
  
      /**
       * Return the mocked objects.
       * 
       * @param engine the {@link MockEngine}
       * @return the map of mocked objects
       */
      public HashMap<Field, Object> getMockedObject( MockEngine engine )
      {
          createMockedObjectBymockFramekork( engine );
          return mockedObjects;
      }
  
      private void createMockedObjectBymockFramekork( MockEngine engine )
      {
          for ( Entry<Field, Object> entry : mockedObjects.entrySet() )
          {
              if ( entry.getValue() instanceof Class<?> )
              {
                  Field field = entry.getKey();
                  Mock mock = field.getAnnotation( Mock.class );
                  mockedObjects.put( entry.getKey(), engine.createMock( (Class<?>) entry.getValue(), mock.type() ) );
              }
          }
      }
  
      
      /**
       * Invoked when the visitor founds an element with a {@link Mock} annotation.
       * @param annotation The {@link Mock} annotation type
       * @param element the {@link Mock} annotated fiels 
       * @throws HandleException when an error occurs.    
       */
      @SuppressWarnings( "unchecked" )
      public void handle( final Mock annotation, final Field element )
          throws HandleException
      {
          final Class<? super Object> type = (Class<? super Object>) element.getDeclaringClass();
  
          if ( LOGGER.isLoggable( Level.FINER ) )
          {
              LOGGER.finer( "      Found annotated field: " + element );
          }
          if ( annotation.providedBy().length() > 0 )
          {
              Class<?> providedClass = type;
              if ( annotation.providerClass() != Object.class )
              {
                  providedClass = annotation.providerClass();
              }
              try
              {
                 Method method = providedClass.getMethod( annotation.providedBy() );
 
                 if ( !element.getType().isAssignableFrom( method.getReturnType() ) )
                 {
                     throw new HandleException( "Impossible to mock %s due to compatibility type, method provider %s#%s returns %s",
                                                element.getDeclaringClass().getName(),
                                                providedClass.getName(),
                                                annotation.providedBy(),
                                                method.getReturnType().getName() );
                 }
                 try
                 {
                     Object mocked = getMockProviderForType( element.getType(), method, type );
                     mockedObjects.put( element, mocked );
                 }
                 catch ( Throwable t )
                 {
                     throw new HandleException( "Impossible to mock %s, method provider %s#%s raised an error: %s",
                                                element.getDeclaringClass().getName(),
                                                providedClass.getName(),
                                                annotation.providedBy(),
                                                t );
                 }
             }
             catch ( SecurityException e )
             {
                 throw new HandleException( "Impossible to mock %s, impossible to access to method provider %s#%s: %s",
                                            element.getDeclaringClass().getName(),
                                            providedClass.getName(),
                                            annotation.providedBy(),
                                            e );
             }
             catch ( NoSuchMethodException e )
             {
                 throw new HandleException( "Impossible to mock %s, the method provider %s#%s doesn't exist.",
                                            element.getDeclaringClass().getName(),
                                            providedClass.getName(),
                                            annotation.providedBy() );
             }
         }
         else
         {
             mockedObjects.put( element, element.getType() );
         }
     }
 
     @SuppressWarnings( "unchecked" )
     private <T> T getMockProviderForType( T t, Method method, Class<?> cls )
         throws HandleException
     {
         if ( method.getReturnType() == t )
         {
             try
             {
                 if ( LOGGER.isLoggable( Level.FINER ) )
                 {
                     LOGGER.finer( "        ...invoke Provider method for Mock: " + method.getName() );
                 }
                 if ( !Modifier.isPublic( method.getModifiers() ) || !Modifier.isStatic( method.getModifiers() ) )
                 {
                     throw new HandleException( "Impossible to invoke method %s#%s. The method shuld be 'static public %s %s()",
                                                cls.getName(),
                                                method.getName(),
                                                method.getReturnType().getName(),
                                                method.getName() );
                 }
 
                 return (T) method.invoke( cls );
             }
             catch ( Exception e )
             {
                 throw new RuntimeException( e );
             }
         }
         throw new HandleException( "The method: %s should return type %s", method, t );
     }
 
 }