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.facets;
  
  import java.lang.reflect.Method;
  import java.util.Optional;
  import java.util.function.BiConsumer;
  import java.util.stream.Collectors;
  
  import org.apache.causeway.applib.services.wrapper.WrapperFactory;
  import org.apache.causeway.commons.collections.Can;
  import org.apache.causeway.commons.internal.reflection._GenericResolver.ResolvedConstructor;
  import org.apache.causeway.commons.internal.reflection._GenericResolver.ResolvedMethod;
  import org.apache.causeway.commons.internal.reflection._MethodFacades;
  import org.apache.causeway.commons.internal.reflection._MethodFacades.MethodFacade;
  import org.apache.causeway.core.metamodel.facetapi.Facet;
  import org.apache.causeway.core.metamodel.spec.ObjectSpecification;
  import org.apache.causeway.core.metamodel.spec.feature.ObjectMember;
  
  import org.jspecify.annotations.NonNull;
  
  /**
   * A {@link Facet} implementation that ultimately wraps a {@link Method} or
   * possibly several equivalent methods, for a Java implementation of a
   * {@link ObjectMember}.
   *
   * <p>
   * Used by <tt>ObjectSpecificationDefault#getMember(Method)</tt> in order to
   * reverse lookup {@link ObjectMember}s from underlying {@link Method}s. So, for
   * example, the facets that represents an action xxx, or an <tt>validateXxx</tt>
   * method, or an <tt>addToXxx</tt> collection, can all be used to lookup the
   * member.
   *
   * <p>
   * Note that {@link Facet}s relating to the class itself (ie for
   * {@link ObjectSpecification}) should not implement this interface.
   */
  public interface ImperativeFacet extends Facet {
  
      /**
       * The {@link Method}s invoked by this {@link Facet}.
       */
      public Can<MethodFacade> getMethods();
  
      public static enum Intent {
          CHECK_IF_HIDDEN,
          CHECK_IF_DISABLED,
          CHECK_IF_VALID,
          ACCESSOR,
          EXECUTE,
          MODIFY_PROPERTY,
          /**
           * Modify property using modify/clear rather than simply using set.
           */
          MODIFY_PROPERTY_SUPPORTING,
          CHOICES_OR_AUTOCOMPLETE,
          DEFAULTS,
          INITIALIZATION,
          LIFECYCLE,
          UI_HINT
      }
  
      /**
       * The intent of this method, so that the {@link WrapperFactory} knows whether to delegate on or to reject.
       */
      public Intent getIntent();
  
      public static void visitAttributes(final ImperativeFacet imperativeFacet, final BiConsumer<String, Object> visitor) {
          var methods = imperativeFacet.getMethods();
          visitor.accept("methods",
                  methods.stream()
                  .map(MethodFacade::toString)
                  .collect(Collectors.joining(", ")));
          methods.forEach(method->
              visitor.accept(
                      "intent." + method.getName(), imperativeFacet.getIntent()));
      }
  
      // -- UTILITIES
  
      public static Intent getIntent(final ObjectMember member, final ResolvedMethod method) {
          var imperativeFacets = member.streamFacets(ImperativeFacet.class)
                  .filter(imperativeFacet->imperativeFacet.containsMethod(method))
                  .collect(Collectors.toList());
  
          switch(imperativeFacets.size()) {
          case 0:
              break;
          case 1:
              return imperativeFacets.get(0).getIntent();
          default:
              Intent intentToReturn = null;
              for (ImperativeFacet imperativeFacet : imperativeFacets) {
                  Intent intent = imperativeFacet.getIntent();
                  if(intentToReturn == null) {
                      intentToReturn = intent;
                  } else if(intentToReturn != intent) {
                      throw new IllegalArgumentException(member.getFeatureIdentifier().toString() +  ": more than one ImperativeFacet for method " + method.name() + " , with inconsistent intents: " + imperativeFacets.toString());
                  }
              }
              return intentToReturn;
          }
          throw new IllegalArgumentException(member.getFeatureIdentifier().toString() +  ": unable to determine intent of " + method.name());
      }
  
      public static Can<MethodFacade> singleMethod(final @NonNull MethodFacade method) {
          return Can.ofSingleton(method);
      }
  
      public static Can<MethodFacade> singleMethod(final ResolvedMethod method, final Optional<ResolvedConstructor> patConstructor) {
          return patConstructor
              .map(patCons->ImperativeFacet.singleParamsAsTupleMethod(method, patCons))
              .orElseGet(()->ImperativeFacet.singleRegularMethod(method));
      }
  
      public static Can<MethodFacade> singleParamsAsTupleMethod(final @NonNull ResolvedMethod patMethod, final ResolvedConstructor patConstructor) {
          return Can.ofSingleton(_MethodFacades.paramsAsTuple(patMethod, patConstructor));
      }
  
      /**
       * Use only for no-arg actions, getters or setters, or support methods!
       */
      public static Can<MethodFacade> singleRegularMethod(final @NonNull ResolvedMethod method) {
          return Can.ofSingleton(_MethodFacades.regular(method));
      }
  
      // -- HELPER
  
      private boolean containsMethod(final ResolvedMethod method) {
          return getMethods().stream()
                  .map(MethodFacade::asMethodForIntrospection)
                  .anyMatch(method::equals);
      }
  
  }
  