/**
    * This file Copyright (c) 2017-2018 Magnolia International
    * Ltd.  (http://www.magnolia-cms.com). All rights reserved.
    *
    *
    * This file is dual-licensed under both the Magnolia
    * Network Agreement and the GNU General Public License.
    * You may elect to use one or the other of these licenses.
    *
   * This file is distributed in the hope that it will be
   * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
   * implied warranty of MERCHANTABILITY or FITNESS FOR A
   * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
   * Redistribution, except as permitted by whichever of the GPL
   * or MNA you select, is prohibited.
   *
   * 1. For the GPL license (GPL), you can redistribute and/or
   * modify this file under the terms of the GNU General
   * Public License, Version 3, as published by the Free Software
   * Foundation.  You should have received a copy of the GNU
   * General Public License, Version 3 along with this program;
   * if not, write to the Free Software Foundation, Inc., 51
   * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * 2. For the Magnolia Network Agreement (MNA), this file
   * and the accompanying materials are made available under the
   * terms of the MNA which accompanies this distribution, and
   * is available at http://www.magnolia-cms.com/mna.html
   *
   * Any modifications to this file must keep this entire header
   * intact.
   *
   */
  package info.magnolia.ui.framework.ioc;
  
  import info.magnolia.objectfactory.annotation.LazySingleton;
  
  import java.lang.annotation.Annotation;
  import java.util.ArrayList;
  import java.util.List;
  import java.util.Objects;
  
  import javax.inject.Singleton;
  
  import com.google.inject.AbstractModule;
  import com.google.inject.Key;
  import com.google.inject.Module;
  import com.google.inject.binder.ScopedBindingBuilder;
  import com.google.inject.internal.Scoping;
  import com.google.inject.spi.Element;
  import com.google.inject.spi.Elements;
  
  /**
   * Wrapper Guice module which inspects all the {@link com.google.inject.Binding bindings} of the source module
   * and re-scopes the {@link Singleton singletons} and {@link LazySingleton lazy singletons}
   * to the appropriate UI-scopes.
   * <p>
   * <strong>NOTE:</strong> unfortunately due to how Guice processes the bindings we cannot
   * detect and process the singletons that are configured via annotations without explicit
   * binding. Such scoping info will be available only on the injector level which is too late
   * for us. In order to handle such 'snaeaky' bindings there is another wrapper module
   * {@link EliminateRedundantSingletonAnnotations}.
   * </p>
   */
  final class RebindUiComponentScopes extends AbstractModule {
  
      private final Module sourceModule;
  
      RebindUiComponentScopes(Module sourceModule) {
          this.sourceModule = sourceModule;
      }
  
      @Override
      @SuppressWarnings("unchecked")
      protected void configure() {
          final List<Element> elements = Elements.getElements(sourceModule);
          final List<Element> elementsToWrite = new ArrayList<>(elements);
  
          GuiceSpi.getBindings(elements).forEach(binding -> {
              final Scoping scoping = GuiceSpi.resolveScope(binding);
  
              if (scoping == null) {
                  return;
              }
  
              final Class<? extends Annotation> scopeAnnotation = scoping.getScopeAnnotation();
  
              if (isSingletonScopeAnnotation(scopeAnnotation)) {
                  boolean isEagerSingleton = isEagerSingletonAnnotation(scopeAnnotation);
                  final UiContextAnnotation uiContextAnnotation = UiAnnotations.cast(binding.getKey().getAnnotation());
                  final Class<? extends Annotation> relatedScopeAnnotation = uiContextAnnotation.getRelatedScopeAnnotation(isEagerSingleton);
  
                  if (!Objects.equals(relatedScopeAnnotation, scopeAnnotation)) {
                      elementsToWrite.remove(binding);
                      final Key key = binding.getKey();
                      GuiceSpi.<ScopedBindingBuilder>inspect(binding)
                              .onLinkedBinding(linkedKeyBinding -> bind(key).to(linkedKeyBinding.getLinkedKey()))
                              .onProviderKeyBinding(providerBinding -> bind(key).toProvider(providerBinding.getProviderKey()))
                              .visit()
                             .ifPresent(scopedBindingBuilder -> scopedBindingBuilder.in(relatedScopeAnnotation));
                 }
             }
         });
 
         elementsToWrite.forEach(element -> element.applyTo(binder()));
     }
 
     private boolean isEagerSingletonAnnotation(Class<? extends Annotation> scopeAnnotation) {
         return scopeAnnotation.equals(Singleton.class) || scopeAnnotation.equals(com.google.inject.Singleton.class);
     }
 
     private boolean isSingletonScopeAnnotation(Class<? extends Annotation> scopeAnnotation) {
         return Objects.equals(scopeAnnotation, Singleton.class) ||
                Objects.equals(scopeAnnotation, com.google.inject.Singleton.class) ||
                Objects.equals(scopeAnnotation, LazySingleton.class);
     }
 }