content: /*
   *  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.causeway.core.metamodel.facetapi;
  
  import org.apache.causeway.applib.Identifier;
  import org.apache.causeway.applib.id.LogicalType;
  import org.apache.causeway.commons.collections.ImmutableEnumSet;
  import org.apache.causeway.commons.internal.reflection._MethodFacades.MethodFacade;
  import org.apache.causeway.commons.semantics.AccessorSemantics;
  import org.apache.causeway.core.metamodel.facets.FacetFactory;
  
  /**
   * Enumerates the features that a particular Facet can be applied to.
   *
   * <p>
   * The class-level feature processing is typically performed by {@link FacetFactory}s
   * pertaining to {@link #OBJECT}, performed before the processing of class members.
   *
   */
  public enum FeatureType {
  
      OBJECT("Object") {
          /**
           * The supplied method can be null; at any rate it will be ignored.
           */
          @Override
          public Identifier identifierFor(final LogicalType typeIdentifier, final MethodFacade method) {
              return Identifier.classIdentifier(typeIdentifier);
          }
      },
      PROPERTY("Property") {
          @Override
          public Identifier identifierFor(final LogicalType typeIdentifier, final MethodFacade method) {
              return Identifier.propertyIdentifier(typeIdentifier,
                      AccessorSemantics.associationIdentifierFor(method.asMethodElseFail())); // expected regular
          }
      },
      COLLECTION("Collection") {
          @Override
          public Identifier identifierFor(final LogicalType typeIdentifier, final MethodFacade method) {
              return Identifier.collectionIdentifier(typeIdentifier,
                      AccessorSemantics.associationIdentifierFor(method.asMethodElseFail())); // expected regular
          }
      },
      ACTION("Action") {
          @Override
          public Identifier identifierFor(final LogicalType typeIdentifier, final MethodFacade method) {
              final String fullMethodName = method.getName();
              final Class<?>[] parameterTypes = method.getParameterTypes();
              return Identifier.actionIdentifier(typeIdentifier, fullMethodName, parameterTypes);
          }
      },
      ACTION_PARAMETER_SINGULAR("Singular Parameter") {
          /**
           * Always returns <tt>null</tt>.
           */
          @Override
          public Identifier identifierFor(final LogicalType typeIdentifier, final MethodFacade method) {
              return null;
          }
      },
      ACTION_PARAMETER_PLURAL("Plural Parameter") {
          /**
           * Always returns <tt>null</tt>.
           */
          @Override
          public Identifier identifierFor(final LogicalType typeIdentifier, final MethodFacade method) {
              return null;
          }
      };
  
      public static final ImmutableEnumSet<FeatureType> COLLECTIONS_ONLY = ImmutableEnumSet.of(COLLECTION);
      public static final ImmutableEnumSet<FeatureType> COLLECTIONS_AND_ACTIONS = ImmutableEnumSet.of(COLLECTION, ACTION);
      public static final ImmutableEnumSet<FeatureType> ACTIONS_ONLY = ImmutableEnumSet.of(ACTION);
      public static final ImmutableEnumSet<FeatureType> PARAMETERS_ONLY = ImmutableEnumSet.of(ACTION_PARAMETER_SINGULAR, ACTION_PARAMETER_PLURAL);
      public static final ImmutableEnumSet<FeatureType> PROPERTIES_ONLY = ImmutableEnumSet.of(PROPERTY);
      public static final ImmutableEnumSet<FeatureType> PROPERTIES_AND_ACTIONS = ImmutableEnumSet.of(PROPERTY, ACTION);
      public static final ImmutableEnumSet<FeatureType> OBJECTS_ONLY = ImmutableEnumSet.of(OBJECT);
      public static final ImmutableEnumSet<FeatureType> MEMBERS = ImmutableEnumSet.of(PROPERTY, COLLECTION, ACTION);
      public static final ImmutableEnumSet<FeatureType> OBJECTS_AND_PROPERTIES = ImmutableEnumSet.of(OBJECT, PROPERTY);
      public static final ImmutableEnumSet<FeatureType> PROPERTIES_AND_COLLECTIONS = ImmutableEnumSet.of(PROPERTY, COLLECTION);
      public static final ImmutableEnumSet<FeatureType> OBJECTS_AND_COLLECTIONS = ImmutableEnumSet.of(OBJECT, COLLECTION);
      public static final ImmutableEnumSet<FeatureType> OBJECTS_AND_ACTIONS = ImmutableEnumSet.of(OBJECT, ACTION);
      public static final ImmutableEnumSet<FeatureType> OBJECTS_PROPERTIES_AND_COLLECTIONS = ImmutableEnumSet.of(OBJECT, PROPERTY, COLLECTION);
      public static final ImmutableEnumSet<FeatureType> ACTIONS_AND_PARAMETERS = ImmutableEnumSet.of(ACTION, ACTION_PARAMETER_SINGULAR, ACTION_PARAMETER_PLURAL);
  
      /**
       * Use of this is discouraged; instead use multiple {@link FacetFactory}s
       * for different features.
       */
      public static final ImmutableEnumSet<FeatureType> EVERYTHING_BUT_PARAMETERS =
              ImmutableEnumSet.complementOf(
                      ImmutableEnumSet.of(ACTION_PARAMETER_SINGULAR, ACTION_PARAMETER_PLURAL));
      /**
       * Use of this is discouraged; instead use multiple {@link FacetFactory}s
       * for different features.
       */
      public static final ImmutableEnumSet<FeatureType> EVERYTHING = ImmutableEnumSet.allOf(FeatureType.class);
  
      private final String name;
  
      private FeatureType(final String name) {
          this.name = name;
      }
  
      public boolean isProperty() { return this == PROPERTY; }
      public boolean isCollection() { return this == COLLECTION; }
      public boolean isAction() { return this == ACTION; }
      public boolean isActionParameter() {
          return this == ACTION_PARAMETER_SINGULAR
                  || this == ACTION_PARAMETER_PLURAL;
      }
  
      /**
       * Convenience.
       */
      public boolean isPropertyOrCollection() {
          return isProperty() || isCollection();
      }
  
      public abstract Identifier identifierFor(LogicalType typeIdentifier, MethodFacade method);
  
      @Override
      public String toString() {
          return name;
      }
  
  }
  