/**
    * 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.hadoop.hbase.regionserver.querymatcher;
  
  import java.io.IOException;
  
  import org.apache.hadoop.hbase.Cell;
  import org.apache.hadoop.hbase.CellUtil;
  import org.apache.hadoop.hbase.KeepDeletedCells;
  import org.apache.hadoop.hbase.classification.InterfaceAudience;
  import org.apache.hadoop.hbase.client.Scan;
  import org.apache.hadoop.hbase.regionserver.DeleteTracker;
  import org.apache.hadoop.hbase.regionserver.RegionCoprocessorHost;
  import org.apache.hadoop.hbase.regionserver.ScanInfo;
  
  /**
   * Query matcher for normal user scan.
   */
  @InterfaceAudience.Private
  public abstract class NormalUserScanQueryMatcher extends UserScanQueryMatcher {
  
    /** Keeps track of deletes */
    private final DeleteTracker deletes;
  
    /** True if we are doing a 'Get' Scan. Every Get is actually a one-row Scan. */
    private final boolean get;
  
    /** whether time range queries can see rows "behind" a delete */
    private final boolean seePastDeleteMarkers;
  
    protected NormalUserScanQueryMatcher(Scan scan, ScanInfo scanInfo, ColumnTracker columns,
        boolean hasNullColumn, DeleteTracker deletes, long oldestUnexpiredTS, long now) {
      super(scan, scanInfo, columns, hasNullColumn, oldestUnexpiredTS, now);
      this.deletes = deletes;
      this.get = scan.isGetScan();
      this.seePastDeleteMarkers = scanInfo.getKeepDeletedCells() != KeepDeletedCells.FALSE;
    }
  
    @Override
    public MatchCode match(Cell cell) throws IOException {
      if (filter != null && filter.filterAllRemaining()) {
        return MatchCode.DONE_SCAN;
      }
      MatchCode returnCode = preCheck(cell);
      if (returnCode != null) {
        return returnCode;
      }
      long timestamp = cell.getTimestamp();
      byte typeByte = cell.getTypeByte();
      if (CellUtil.isDelete(typeByte)) {
        boolean includeDeleteMarker = seePastDeleteMarkers ? tr.withinTimeRange(timestamp)
            : tr.withinOrAfterTimeRange(timestamp);
        if (includeDeleteMarker) {
          this.deletes.add(cell);
        }
        return MatchCode.SKIP;
      }
      returnCode = checkDeleted(deletes, cell);
      if (returnCode != null) {
        return returnCode;
      }
      return matchColumn(cell, timestamp, typeByte);
    }
  
    @Override
    protected void reset() {
      deletes.reset();
    }
  
    @Override
    protected boolean isGet() {
      return get;
    }
  
    public static NormalUserScanQueryMatcher create(Scan scan, ScanInfo scanInfo,
        ColumnTracker columns, boolean hasNullColumn, long oldestUnexpiredTS, long now,
        RegionCoprocessorHost regionCoprocessorHost) throws IOException {
      DeleteTracker deletes = instantiateDeleteTracker(regionCoprocessorHost);
      if (scan.isReversed()) {
        if (scan.includeStopRow()) {
          return new NormalUserScanQueryMatcher(scan, scanInfo, columns, hasNullColumn, deletes,
              oldestUnexpiredTS, now) {
  
            @Override
           protected boolean moreRowsMayExistsAfter(int cmpToStopRow) {
             return cmpToStopRow >= 0;
           }
         };
       } else {
         return new NormalUserScanQueryMatcher(scan, scanInfo, columns, hasNullColumn, deletes,
             oldestUnexpiredTS, now) {
 
           @Override
           protected boolean moreRowsMayExistsAfter(int cmpToStopRow) {
             return cmpToStopRow > 0;
           }
         };
       }
     } else {
       if (scan.includeStopRow()) {
         return new NormalUserScanQueryMatcher(scan, scanInfo, columns, hasNullColumn, deletes,
             oldestUnexpiredTS, now) {
 
           @Override
           protected boolean moreRowsMayExistsAfter(int cmpToStopRow) {
             return cmpToStopRow <= 0;
           }
         };
       } else {
         return new NormalUserScanQueryMatcher(scan, scanInfo, columns, hasNullColumn, deletes,
             oldestUnexpiredTS, now) {
 
           @Override
           protected boolean moreRowsMayExistsAfter(int cmpToStopRow) {
             return cmpToStopRow < 0;
           }
         };
       }
     }
   }
 }