/*
    * 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.eclipse.aether.util.version;
  
  import java.util.Objects;
  
  import org.eclipse.aether.version.Version;
  import org.eclipse.aether.version.VersionConstraint;
  import org.eclipse.aether.version.VersionRange;
  
  import static java.util.Objects.requireNonNull;
  
  /**
   * A constraint on versions for a dependency.
   * <p>
   * Despite its name, this class is generic in a sense it works with any {@link Version}.
   */
  final class GenericVersionConstraint implements VersionConstraint {
  
      private final VersionRange range;
  
      private final Version version;
  
      /**
       * Creates a version constraint from the specified version range.
       *
       * @param range The version range, must not be {@code null}.
       */
      GenericVersionConstraint(VersionRange range) {
          this.range = requireNonNull(range, "version range cannot be null");
          this.version = null;
      }
  
      /**
       * Creates a version constraint from the specified version.
       *
       * @param version The version, must not be {@code null}.
       */
      GenericVersionConstraint(Version version) {
          this.version = requireNonNull(version, "version cannot be null");
          this.range = null;
      }
  
      @Override
      public VersionRange getRange() {
          return range;
      }
  
      @Override
      public Version getVersion() {
          return version;
      }
  
      @Override
      public boolean containsVersion(Version version) {
          if (range == null) {
              return version.equals(this.version);
          } else {
              return range.containsVersion(version);
          }
      }
  
      @Override
      public String toString() {
          return String.valueOf((range == null) ? version : range);
      }
  
      @Override
      public boolean equals(Object obj) {
          if (this == obj) {
              return true;
          }
          if (obj == null || !getClass().equals(obj.getClass())) {
              return false;
          }
  
          VersionConstraint that = (VersionConstraint) obj;
  
          return Objects.equals(range, that.getRange()) && Objects.equals(version, that.getVersion());
      }
  
      @Override
      public int hashCode() {
         int hash = 17;
         hash = hash * 31 + hash(getRange());
         hash = hash * 31 + hash(getVersion());
         return hash;
     }
 
     private static int hash(Object obj) {
         return obj != null ? obj.hashCode() : 0;
     }
 }