/*
 * Copyright 1998-2014 University Corporation for Atmospheric Research/Unidata
 *
 *   Portions of this software were developed by the Unidata Program at the
 *   University Corporation for Atmospheric Research.
 *
 *   Access and use of this software shall impose the following obligations
 *   and understandings on the user. The user is granted the right, without
 *   any fee or cost, to use, copy, modify, alter, enhance and distribute
 *   this software, and any derivative works thereof, and its supporting
 *   documentation for any purpose whatsoever, provided that this entire
 *   notice appears in all copies of the software, derivative works and
 *   supporting documentation.  Further, UCAR requests that the user credit
 *   UCAR/Unidata in any publications that result from the use of this
 *   software or in any product that includes this software. The names UCAR
 *   and/or Unidata, however, may not be used in any advertising or publicity
 *   to endorse or promote any products or commercial entity unless specific
 *   written permission is obtained from UCAR/Unidata. The user also
 *   understands that UCAR/Unidata is not obligated to provide the user with
 *   any support, consulting, training or assistance of any kind with regard
 *   to the use, operation and performance of this software nor to provide
 *   the user with any updates, revisions, new versions or "bug fixes."
 *
 *   THIS SOFTWARE IS PROVIDED BY UCAR/UNIDATA "AS IS" AND ANY EXPRESS OR
 *   IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 *   WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 *   DISCLAIMED. IN NO EVENT SHALL UCAR/UNIDATA BE LIABLE FOR ANY SPECIAL,
 *   INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
 *   FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
 *   NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
 *   WITH THE ACCESS, USE OR PERFORMANCE OF THIS SOFTWARE.
 */
package ucar.nc2;

import ucar.ma2.*;
import ucar.nc2.util.CancelTask;

import java.io.IOException;

/**
 * A ProxyReader for logical sections of a Variable.
 *
 * @author caron
 * @see Variable#section(Section subsection)
 */

class SectionReader implements ProxyReader {
  static private org.slf4j.Logger log = org.slf4j.LoggerFactory.getLogger(SectionReader.class);
  private Section orgSection;   // section of the original
  private Variable orgClient;

  // section must be filled
  SectionReader(Variable orgClient, Section section) throws InvalidRangeException {
    this.orgClient = orgClient;
    this.orgSection = section.isImmutable() ? section : new Section(section.getRanges());
  }

  @Override
  public Array reallyRead(Variable client, CancelTask cancelTask) throws IOException {
    try {
      return orgClient._read( orgSection);
    } catch (InvalidRangeException e) {
      try {
        orgClient._read( orgSection); // debug
      } catch (InvalidRangeException e1) {
        e1.printStackTrace();
      }
      throw new RuntimeException(e);
    }
  }

  @Override
  public Array reallyRead(Variable client, Section section, CancelTask cancelTask) throws IOException, InvalidRangeException {
    Section want = orgSection.compose( section);
    return orgClient._read( want);
  }

}