/*
 * 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.vxquery.runtime.functions.node;

import org.apache.vxquery.datamodel.accessors.TaggedValuePointable;
import org.apache.vxquery.datamodel.accessors.TypedPointables;
import org.apache.vxquery.datamodel.values.ValueTag;
import org.apache.vxquery.datamodel.values.XDMConstants;
import org.apache.vxquery.exceptions.ErrorCode;
import org.apache.vxquery.exceptions.SystemException;
import org.apache.vxquery.runtime.functions.base.AbstractTaggedValueArgumentScalarEvaluator;
import org.apache.vxquery.runtime.functions.util.FunctionHelper;

import org.apache.hyracks.algebricks.runtime.base.IScalarEvaluator;
import org.apache.hyracks.data.std.api.IPointable;

public abstract class AbstractNodePositionalCheckEvaluator extends AbstractTaggedValueArgumentScalarEvaluator {

    public AbstractNodePositionalCheckEvaluator(IScalarEvaluator[] args) {
        super(args);
    }

    private final TypedPointables tp = new TypedPointables();

    @Override
    protected void evaluate(TaggedValuePointable[] args, IPointable result) throws SystemException {

        if (args[0].getTag() != ValueTag.NODE_TREE_TAG) {
            throw new SystemException(ErrorCode.FORG0006);
        }
        if (args[1].getTag() != ValueTag.NODE_TREE_TAG) {
            throw new SystemException(ErrorCode.FORG0006);
        }

        if (nodeCompare(FunctionHelper.getLocalNodeId(args[0], tp), FunctionHelper.getLocalNodeId(args[1], tp))) {
            XDMConstants.setTrue(result);
        } else {
            XDMConstants.setFalse(result);
        }
    }

    abstract protected boolean nodeCompare(int firstId, int secondId);
}