/**
 * 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.smartdata.rule.parser;

import java.io.IOException;

public class OperNode extends TreeNode {
  private OperatorType operatorType;

  public OperNode(OperatorType type, TreeNode left, TreeNode right) {
    super(left, right);
    operatorType = type;
  }

  // return this node's return type
  public ValueType getValueType() {
    if (operatorType.isLogicalOperation()) {
      return ValueType.BOOLEAN;
    }

    ValueType l = left.getValueType();
    ValueType r = right.getValueType();

    switch (operatorType) {
      case ADD:
        if ((l == ValueType.TIMEPOINT && r == ValueType.TIMEINTVAL)
            || (r == ValueType.TIMEPOINT && l == ValueType.TIMEINTVAL)) {
          return ValueType.TIMEPOINT;
        }
        return l;

      case SUB:
        if (l == ValueType.TIMEPOINT) {
          if (r == ValueType.TIMEINTVAL) {
            return ValueType.TIMEPOINT;
          } else if (r == ValueType.TIMEPOINT) {
            return ValueType.TIMEINTVAL;
          }
        }
        return l;
    }
    return left.getValueType();
  }

  public OperatorType getOperatorType() {
    return operatorType;
  }

  // TODO: check if any miss match in the tree
  public void checkValueType() throws IOException {
  }

  public VisitResult eval() throws IOException {
    return left.eval().eval(operatorType, right == null ? null : right.eval());
  }

  public boolean isOperNode() {
    return true;
  }
}
