package org.treetank.io;
   
   import static com.google.common.base.Objects.toStringHelper;
   
   import com.sleepycat.bind.tuple.TupleBinding;
   import com.sleepycat.bind.tuple.TupleInput;
   import com.sleepycat.bind.tuple.TupleOutput;
   
   /**
   * Container for Key-Entry in the log determining the level and the the sequence in the level.
   * Needed for the WriteTrx for getting inserting any modified buckets in the right order since the bucket-key
   * can not be computed from the datakeys due to the relative position of the datas in the subtree of the
   * related
   * RevisionRootBucket.
   * 
   * @author Sebastian Graf, University of Konstanz
   * 
   */
  public class LogKey {
  
      /** Is this key referencing to the root level or to the data level. */
      private final boolean mRootLevel;
  
      /** Level Key. */
      private final int mLevel;
  
      /** Sequence Key. */
      private final long mSeq;
  
      /**
       * Constructor.
       * 
       * @param pRootLevel
       * 
       * 
       *            is key part of the revision-part or the data-part
       * @param pLevel
       *            to be set.
       * @param pSeq
       *            to be set.
       */
      public LogKey(final boolean pRootLevel, final int pLevel, final long pSeq) {
          mRootLevel = pRootLevel;
          mLevel = pLevel;
          mSeq = pSeq;
      }
  
      /**
       * 
       * Getting the level key.
       * 
       * @return the mLevel
       */
      public int getLevel() {
          return mLevel;
      }
  
      /**
       * Getting the seq key.
       * 
       * @return the mSeq
       */
      public long getSeq() {
          return mSeq;
      }
  
      /**
       * Getter for mRootLevel.
       * 
       * @return the mRootLevel
       */
      public boolean isRootLevel() {
          return mRootLevel;
      }
  
      /**
       * {@inheritDoc}
       */
      @Override
      public int hashCode() {
          final int prime = 31;
          int result = 1;
          result = prime * result + (int)(mLevel ^ (mLevel >>> 32));
          result = prime * result + (mRootLevel ? 1231 : 1237);
          result = prime * result + (int)(mSeq ^ (mSeq >>> 32));
          return result;
      }
  
      /**
       * {@inheritDoc}
       */
      @Override
      public boolean equals(Object obj) {
          if (this == obj)
              return true;
          if (obj == null)
              return false;
          if (getClass() != obj.getClass())
              return false;
         LogKey other = (LogKey)obj;
         if (mLevel != other.mLevel)
             return false;
         if (mRootLevel != other.mRootLevel)
             return false;
         if (mSeq != other.mSeq)
             return false;
         return true;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public String toString() {
         return toStringHelper(this).add("mRootLevel", mRootLevel).add("mLevel", mLevel).add("mSeq", mSeq)
             .toString();
     }
 
     /**
      * Binding for serializing LogKeys in the BDB.
      * 
      * @author Sebastian Graf, University of Konstanz
      * 
      */
     static class LogKeyBinding extends TupleBinding<LogKey> {
 
         /**
          * {@inheritDoc}
          */
         @Override
         public LogKey entryToObject(TupleInput arg0) {
             final LogKey key = new LogKey(arg0.readBoolean(), arg0.readInt(), arg0.readLong());
             return key;
         }
 
         /**
          * {@inheritDoc}
          */
         @Override
         public void objectToEntry(LogKey arg0, TupleOutput arg1) {
             arg1.writeBoolean(arg0.isRootLevel());
             arg1.writeInt(arg0.getLevel());
             arg1.writeLong(arg0.getSeq());
         }
 
     }
 
 }