/*
    * Licensed to The Apereo Foundation under one or more contributor license
    * agreements. See the NOTICE file distributed with this work for additional
    * information regarding copyright ownership.
    *
    *
    * The Apereo Foundation licenses this file to you under the Educational
    * Community 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://opensource.org/licenses/ecl2.txt
   *
   * 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.opencastproject.assetmanager.impl;
  
  import static org.opencastproject.util.EqualsUtil.hash;
  
  import org.opencastproject.assetmanager.api.Version;
  
  import javax.annotation.ParametersAreNonnullByDefault;
  
  /**
   * The version of an archived media package or element.
   * <p>
   * This class encapsulates the actual data type used for identifying versions to minimize
   * API changes.
   */
  @ParametersAreNonnullByDefault
  public final class VersionImpl implements Version {
    private static final long serialVersionUID = 3060347920702655628L;
  
    public static final VersionImpl FIRST = mk(0L);
  
    private final long nr;
  
    public VersionImpl(long nr) {
      this.nr = nr;
    }
  
    /** Constructor function. */
    public static VersionImpl mk(long nr) {
      return new VersionImpl(nr);
    }
  
    public static VersionImpl mk(Version v) {
      return new VersionImpl(Long.parseLong(v.toString()));
    }
  
    /** Create the next version after the <code>latest</code>. */
    public static VersionImpl next(long latest) {
      return new VersionImpl(latest + 1);
    }
  
    public long value() {
      return nr;
    }
  
    @Override
    public boolean isOlder(Version v) {
      return compareTo(v) < 0;
    }
  
    @Override
    public boolean isYounger(Version v) {
      return compareTo(v) > 0;
    }
  
    @Override
    public int compareTo(Version v) {
      return Long.compare(nr, RuntimeTypes.convert(v).nr);
    }
  
    @Override
    public boolean equals(Object that) {
      return (this == that) || (that instanceof VersionImpl && eqFields((VersionImpl) that));
    }
  
    private boolean eqFields(VersionImpl that) {
      return this.nr == that.nr;
    }
  
    @Override
    public int hashCode() {
      return hash(nr);
    }
  
    @Override
    public String toString() {
      return String.valueOf(nr);
    }
  }