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.extensions.secman.applib.permission.dom;
  
  import java.io.Serializable;
  import java.util.Comparator;
  
  import org.apache.causeway.applib.annotation.Programmatic;
  import org.apache.causeway.applib.services.appfeat.ApplicationFeatureId;
  import org.apache.causeway.applib.util.ObjectContracts;
  import org.apache.causeway.applib.util.ToString;
  
  /**
   * A serializable value object representing an (anonymized)
   * {@link ApplicationPermission}.
   *
   * <p>
   *     Intended for value type arithmetic and also for caching.  No user/role information is held because that information
   *     is not required to perform the arithmetic.
   * </p>
   *
   * @since 2.0 {@index}
   */
  public class ApplicationPermissionValue implements Comparable<ApplicationPermissionValue>, Serializable {
  
      private static final long serialVersionUID = 1L;
  
      // -- constructor
      public ApplicationPermissionValue(
              final ApplicationFeatureId featureId,
              final ApplicationPermissionRule rule,
              final ApplicationPermissionMode mode) {
          this.featureId = featureId;
          this.rule = rule;
          this.mode = mode;
      }
  
      // -- featureId
      private final ApplicationFeatureId featureId;
      @Programmatic
      public ApplicationFeatureId getFeatureId() {
          return featureId;
      }
  
      // -- rule
      private final ApplicationPermissionRule rule;
      @Programmatic
      public ApplicationPermissionRule getRule() {
          return rule;
      }
  
      // -- mode
      private final ApplicationPermissionMode mode;
      @Programmatic
      public ApplicationPermissionMode getMode() {
          return mode;
      }
  
      // -- implies, refutes
      @Programmatic
      public boolean implies(final ApplicationFeatureId featureId, final ApplicationPermissionMode mode) {
          if(getRule() != ApplicationPermissionRule.ALLOW) {
              // only allow rules can imply
              return false;
          }
          if(getMode() == ApplicationPermissionMode.VIEWING && mode == ApplicationPermissionMode.CHANGING) {
              // an "allow viewing" permission does not imply ability to change
              return false;
          }
  
          // determine if this permission is on the path (ie the feature or one of its parents)
          return onPathOf(featureId);
      }
  
      @Programmatic
      public boolean refutes(final ApplicationFeatureId featureId, final ApplicationPermissionMode mode) {
          if(getRule() != ApplicationPermissionRule.VETO) {
              // only veto rules can refute
              return false;
          }
          if(getMode() == ApplicationPermissionMode.CHANGING && mode == ApplicationPermissionMode.VIEWING) {
              // an "veto changing" permission does not refute ability to view
              return false;
          }
          // determine if this permission is on the path (ie the feature or one of its parents)
          return onPathOf(featureId);
      }
  
      private boolean onPathOf(final ApplicationFeatureId featureId) {
  
          for (final ApplicationFeatureId pathId : featureId.getPathIds()) {
              if(getFeatureId().equals(pathId)) {
                  return true;
              }
          }
  
          return false;
      }
  
      @Programmatic
      public ApplicationPermissionValue withFeatureId(ApplicationFeatureId applicationFeatureId) {
          return new ApplicationPermissionValue(applicationFeatureId, this.rule, this.mode);
      }
  
      // -- Comparators
      public static final class Comparators {
          private Comparators(){}
          public static Comparator<ApplicationPermissionValue> natural() {
              return new ApplicationPermissionValueComparator();
          }
  
          static class ApplicationPermissionValueComparator implements Comparator<ApplicationPermissionValue>, Serializable {
              private static final long serialVersionUID = 1L;
  
              @Override
              public int compare(final ApplicationPermissionValue o1, final ApplicationPermissionValue o2) {
                  return o1.compareTo(o2);
              }
          }
      }
  
      // -- CONTRACT
  
      private static final Comparator<ApplicationPermissionValue> comparator =
              Comparator.comparing(ApplicationPermissionValue::getRule)
              .thenComparing(ApplicationPermissionValue::getMode)
              .thenComparing(ApplicationPermissionValue::getFeatureId);
  
      private static final ToString<ApplicationPermissionValue> toString =
              ObjectContracts.toString("name", ApplicationPermissionValue::getRule)
              .thenToString("mode", ApplicationPermissionValue::getMode)
              .thenToString("featureId", ApplicationPermissionValue::getFeatureId);
  
      @Override
      public int compareTo(final ApplicationPermissionValue o) {
          return comparator.compare(this, o);
      }
  
      @Override
      public boolean equals(final Object o) {
          // not using because trying to be efficient.  Premature optimization?
          // return ObjectContracts.equals(this, obj, propertyNames);
          if (this == o) return true;
          if (o == null || getClass() != o.getClass()) return false;
  
          final ApplicationPermissionValue that = (ApplicationPermissionValue) o;
  
          if (featureId != null ? !featureId.equals(that.featureId) : that.featureId != null) return false;
          if (mode != that.mode) return false;
          if (rule != that.rule) return false;
  
          return true;
      }
  
      @Override
      public int hashCode() {
          // not using because trying to be efficient.  Premature optimization?
          // return ObjectContracts.hashCode(this, propertyNames);
          int result = featureId != null ? featureId.hashCode() : 0;
          result = 31 * result + (rule != null ? rule.hashCode() : 0);
          result = 31 * result + (mode != null ? mode.hashCode() : 0);
          return result;
      }
  
      @Override
      public String toString() {
          return toString.toString(this);
      }
  
  }
  