/*
 * 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.sql.SQLException;
import java.util.List;
import org.apache.hadoop.hbase.io.ImmutableBytesWritable;
import org.apache.phoenix.expression.Expression;
import org.apache.phoenix.parse.FunctionParseNode.Argument;
import org.apache.phoenix.parse.FunctionParseNode.BuiltInFunction;
import org.apache.phoenix.schema.tuple.Tuple;
import org.apache.phoenix.schema.types.PDataType;
import org.apache.phoenix.schema.types.PInteger;
import org.apache.phoenix.schema.types.PTimestamp;
import org.joda.time.DateTime;
import org.joda.time.chrono.GJChronology;

/**
 * Implementation of the Second() buildin. Input Date/Timestamp/Time. Returns an integer from 0 to
 * 59 representing the second component of time
 */
@BuiltInFunction(name = SecondFunction.NAME,
    args = { @Argument(allowedTypes = { PTimestamp.class }) })
public class SecondFunction extends DateScalarFunction {
  public static final String NAME = "SECOND";

  public SecondFunction() {
  }

  public SecondFunction(List<Expression> children) throws SQLException {
    super(children);
  }

  @Override
  public boolean evaluate(Tuple tuple, ImmutableBytesWritable ptr) {
    Expression expression = getChildExpression();
    if (!expression.evaluate(tuple, ptr)) {
      return false;
    }
    if (ptr.getLength() == 0) {
      return true; // means null
    }
    long dateTime = inputCodec.decodeLong(ptr, expression.getSortOrder());
    DateTime dt = new DateTime(dateTime, GJChronology.getInstanceUTC());
    int sec = dt.getSecondOfMinute();
    PDataType returnType = getDataType();
    byte[] byteValue = new byte[returnType.getByteSize()];
    returnType.getCodec().encodeInt(sec, byteValue, 0);
    ptr.set(byteValue);
    return true;
  }

  @Override
  public PDataType getDataType() {
    return PInteger.INSTANCE;
  }

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

  private Expression getChildExpression() {
    return children.get(0);
  }
}
