content: /*
   * 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.calcite.adapter.enumerable;
  
  import org.apache.calcite.linq4j.tree.Expression;
  
  /**
   * Provides information on the current window when computing the result of
   * the aggregation.
   */
  public interface WinAggFrameResultContext extends WinAggFrameContext {
    /**
     * Converts absolute index position of the given relative position.
     *
     * @param offset offset of the requested row
     * @param seekType the type of offset (start of window, end of window, etc)
     * @return absolute position of the requested row
     */
    Expression computeIndex(Expression offset,
        WinAggImplementor.SeekType seekType);
  
    /**
     * Returns boolean the expression that checks if the given index is in
     * the frame bounds.
     *
     * @param rowIndex index if the row to check
     * @return expression that validates frame bounds for the given index
     */
    Expression rowInFrame(Expression rowIndex);
  
    /**
     * Returns boolean the expression that checks if the given index is in
     * the partition bounds.
     *
     * @param rowIndex index if the row to check
     * @return expression that validates partition bounds for the given index
     */
    Expression rowInPartition(Expression rowIndex);
  
    /**
     * Returns row translator for given absolute row position.
     *
     * @param rowIndex absolute index of the row.
     * @return translator for the requested row
     */
    RexToLixTranslator rowTranslator(Expression rowIndex);
  
    /**
     * Compares two rows given by absolute positions according to the order
     * collation of the current window.
     *
     * @param a absolute index of the first row
     * @param b absolute index of the second row
     * @return result of comparison as as in {@link Comparable#compareTo}
     */
    Expression compareRows(Expression a, Expression b);
  }
  