/*
    * 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.util;
  
  import com.google.common.collect.Lists;
  
  import java.io.IOException;
  import java.io.OutputStream;
  import java.util.ArrayList;
  import java.util.Collection;
  
  import org.apache.hadoop.hbase.classification.InterfaceAudience;
  import org.apache.hadoop.hbase.classification.InterfaceStability;
  
  /**
   * Utility methods for working with {@link ByteRange}.
   */
  @InterfaceAudience.Public
  @InterfaceStability.Evolving
  public class ByteRangeUtils {
    public static int numEqualPrefixBytes(ByteRange left, ByteRange right, int rightInnerOffset) {
      int maxCompares = Math.min(left.getLength(), right.getLength() - rightInnerOffset);
      final byte[] lbytes = left.getBytes();
      final byte[] rbytes = right.getBytes();
      final int loffset = left.getOffset();
      final int roffset = right.getOffset();
      for (int i = 0; i < maxCompares; ++i) {
        if (lbytes[loffset + i] != rbytes[roffset + rightInnerOffset + i]) {
          return i;
        }
      }
      return maxCompares;
    }
  
    public static ArrayList<byte[]> copyToNewArrays(Collection<ByteRange> ranges) {
      if (ranges == null) {
        return new ArrayList<>(0);
      }
      ArrayList<byte[]> arrays = Lists.newArrayListWithCapacity(ranges.size());
      for (ByteRange range : ranges) {
        arrays.add(range.deepCopyToNewArray());
      }
      return arrays;
    }
  
    public static ArrayList<ByteRange> fromArrays(Collection<byte[]> arrays) {
      if (arrays == null) {
        return new ArrayList<>(0);
      }
      ArrayList<ByteRange> ranges = Lists.newArrayListWithCapacity(arrays.size());
      for (byte[] array : arrays) {
        ranges.add(new SimpleMutableByteRange(array));
      }
      return ranges;
    }
  
    public static void write(OutputStream os, ByteRange byteRange) throws IOException {
      os.write(byteRange.getBytes(), byteRange.getOffset(), byteRange.getLength());
    }
  
    public static void write(OutputStream os, ByteRange byteRange, int byteRangeInnerOffset)
        throws IOException {
      os.write(byteRange.getBytes(), byteRange.getOffset() + byteRangeInnerOffset,
        byteRange.getLength() - byteRangeInnerOffset);
    }
  }