/*
 * 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.phoenix.expression.function;

import java.util.List;
import org.apache.hadoop.hbase.io.ImmutableBytesWritable;
import org.apache.phoenix.expression.Expression;
import org.apache.phoenix.parse.ArrayModifierParseNode;
import org.apache.phoenix.parse.FunctionParseNode;
import org.apache.phoenix.schema.SortOrder;
import org.apache.phoenix.schema.TypeMismatchException;
import org.apache.phoenix.schema.types.PArrayDataTypeDecoder;
import org.apache.phoenix.schema.types.PArrayDataTypeEncoder;
import org.apache.phoenix.schema.types.PBinaryArray;
import org.apache.phoenix.schema.types.PChar;
import org.apache.phoenix.schema.types.PDataType;
import org.apache.phoenix.schema.types.PVarbinary;
import org.apache.phoenix.schema.types.PVarbinaryArray;
import org.apache.phoenix.util.StringUtil;

@FunctionParseNode.BuiltInFunction(name = ArrayRemoveFunction.NAME,
    nodeClass = ArrayModifierParseNode.class,
    args = {
      @FunctionParseNode.Argument(allowedTypes = { PBinaryArray.class, PVarbinaryArray.class }),
      @FunctionParseNode.Argument(allowedTypes = { PVarbinary.class }) })
public class ArrayRemoveFunction extends ArrayModifierFunction {

  public static final String NAME = "ARRAY_REMOVE";

  public ArrayRemoveFunction() {
  }

  public ArrayRemoveFunction(List<Expression> children) throws TypeMismatchException {
    super(children);
  }

  @Override
  protected boolean modifierFunction(ImmutableBytesWritable ptr, int length, int offset,
    byte[] arrayBytes, PDataType baseType, int arrayLength, Integer maxLength,
    Expression arrayExp) {
    SortOrder sortOrder = arrayExp.getSortOrder();

    if (ptr.getLength() == 0 || arrayBytes.length == 0) {
      ptr.set(arrayBytes, offset, length);
      return true;
    }

    PArrayDataTypeEncoder arrayDataTypeEncoder = new PArrayDataTypeEncoder(baseType, sortOrder);

    if (getRHSBaseType().equals(PChar.INSTANCE)) {
      int unpaddedCharLength =
        StringUtil.getUnpaddedCharLength(ptr.get(), ptr.getOffset(), ptr.getLength(), sortOrder);
      ptr.set(ptr.get(), offset, unpaddedCharLength);
    }

    for (int arrayIndex = 0; arrayIndex < arrayLength; arrayIndex++) {
      ImmutableBytesWritable ptr2 = new ImmutableBytesWritable(arrayBytes, offset, length);
      PArrayDataTypeDecoder.positionAtArrayElement(ptr2, arrayIndex, baseType, maxLength);
      if (baseType.compareTo(ptr2, sortOrder, ptr, sortOrder, baseType) != 0) {
        arrayDataTypeEncoder.appendValue(ptr2.get(), ptr2.getOffset(), ptr2.getLength());
      }
    }

    ptr.set(arrayDataTypeEncoder.encode());

    return true;
  }

  @Override
  public String getName() {
    return NAME;
  }

}
