/*
 * INESC-ID, Instituto de Engenharia de Sistemas e Computadores Investigação e Desevolvimento em Lisboa
 * Copyright 2013 INESC-ID and/or its affiliates and other
 * contributors as indicated by the @author tags. All rights reserved.
 * See the copyright.txt in the distribution for a full listing of
 * individual contributors.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 3.0 of
 * the License, or (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */
package org.infinispan.container.versioning.gmu;

import org.infinispan.container.versioning.IncrementableEntryVersion;
import org.infinispan.container.versioning.InequalVersionComparisonResult;
import org.infinispan.container.versioning.VersionGenerator;
import org.infinispan.dataplacement.ClusterSnapshot;
import org.infinispan.factories.ComponentRegistry;
import org.infinispan.factories.GlobalComponentRegistry;
import org.infinispan.remoting.transport.Address;

import static org.infinispan.transaction.gmu.GMUHelper.toGMUVersionGenerator;

/**
 * // TODO: Document this
 *
 * @author Pedro Ruivo
 * @since 5.2
 */
public abstract class GMUVersion implements IncrementableEntryVersion {

   public static final long NON_EXISTING = -1;

   protected final int viewId;
   protected final String cacheName;
   protected transient ClusterSnapshot clusterSnapshot;

   protected GMUVersion(String cacheName, int viewId, GMUVersionGenerator versionGenerator) {
      this.cacheName = cacheName;
      this.viewId = viewId;
      clusterSnapshot = versionGenerator.getClusterSnapshot(viewId);
      checkState();
   }

   protected GMUVersion(String cacheName, int viewId, ClusterSnapshot clusterSnapshot) {
      this.cacheName = cacheName;
      this.viewId = viewId;
      this.clusterSnapshot = clusterSnapshot;
      checkState();
   }

   public final int getViewId() {
      return viewId;
   }

   public abstract long getVersionValue(Address address);

   public abstract long getVersionValue(int addressIndex);

   public abstract long getThisNodeVersionValue();

   public static String versionsToString(long[] versions, ClusterSnapshot clusterSnapshot) {
      if (versions == null || versions.length == 0) {
         return "[]";
      } else if (clusterSnapshot != null && versions.length != clusterSnapshot.size()) {
         return "[N/A]";
      }

      if (clusterSnapshot == null) {
         if (versions.length == 1) {
            return "[" + versions[0] + "]";
         } else {
            StringBuilder stringBuilder = new StringBuilder("[");
            stringBuilder.append(versions[0]);
            for (int i = 1; i < versions.length; ++i) {
               stringBuilder.append(",").append(versions[i]);
            }
            return stringBuilder.append("]").toString();
         }
      }
      if (versions.length == 1) {
         return "[" + clusterSnapshot.get(0) + "=" + versions[0] + "]";
      } else {
         StringBuilder stringBuilder = new StringBuilder("[");
         stringBuilder.append(clusterSnapshot.get(0)).append("=").append(versions[0]);

         for (int i = 1; i < versions.length; ++i) {
            stringBuilder.append(",").append(clusterSnapshot.get(i)).append("=").append(versions[i]);
         }
         return stringBuilder.append("]").toString();
      }
   }

   protected final void checkState() {
      if (clusterSnapshot == null) {
         throw new IllegalStateException("Cluster Snapshot in GMU entry version cannot be null");
      }
   }

   protected final InequalVersionComparisonResult compare(long value1, long value2) {
      if (value1 == NON_EXISTING) {
         return InequalVersionComparisonResult.BEFORE;
      } else if (value2 == NON_EXISTING) {
         return InequalVersionComparisonResult.AFTER;
      }

      int compare = Long.valueOf(value1).compareTo(value2);
      if (compare < 0) {
         return InequalVersionComparisonResult.BEFORE;
      } else if (compare == 0) {
         return InequalVersionComparisonResult.EQUAL;
      }
      return InequalVersionComparisonResult.AFTER;
   }

   protected static GMUVersionGenerator getGMUVersionGenerator(GlobalComponentRegistry globalComponentRegistry,
                                                               String cacheName) {
      ComponentRegistry componentRegistry = globalComponentRegistry.getNamedComponentRegistry(cacheName);
      VersionGenerator versionGenerator = componentRegistry.getComponent(VersionGenerator.class);
      return toGMUVersionGenerator(versionGenerator);
   }

   @Override
   public String toString() {
      return "viewId=" + viewId +
            ", cacheName=" + cacheName +
            '}';
   }
}