/*
 * 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;

import java.util.List;

import org.apache.hadoop.hbase.io.ImmutableBytesWritable;
import org.apache.phoenix.schema.tuple.Tuple;
import org.apache.phoenix.schema.types.PDataType;
import org.apache.phoenix.schema.types.PLong;


public class LongAddExpression extends AddExpression {

    public LongAddExpression() {
    }

    public LongAddExpression(List<Expression> children) {
        super(children);
    }

    @Override
    public boolean evaluate(Tuple tuple, ImmutableBytesWritable ptr) {
        long finalResult=0;
        
        for(int i=0;i<children.size();i++) {
            Expression child = children.get(i);
            if (!child.evaluate(tuple, ptr) || ptr.getLength() == 0) {
                return false;
            }
            long childvalue = child.getDataType().getCodec().decodeLong(ptr, child.getSortOrder());
            finalResult += childvalue;
        }
        byte[] resultPtr=new byte[PLong.INSTANCE.getByteSize()];
        getDataType().getCodec().encodeLong(finalResult, resultPtr, 0);
        ptr.set(resultPtr);
        return true;
    }

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

    @Override
    public ArithmeticExpression clone(List<Expression> children) {
        return new LongAddExpression(children);
    }

}