/******************************************************************************
 * $Id: hfa_overviews.cpp,v 1.1 2005/09/17 03:47:41 fwarmerdam Exp $
 *
 * Project:  Erdas Imagine Driver
 * Purpose:  Entry point for building overviews, used by non-imagine formats.
 * Author:   Frank Warmerdam, warmerdam@pobox.com
 *
 ******************************************************************************
 * Copyright (c) 2005, Frank Warmerdam
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 *****************************************************************************
 *
 * $Log: hfa_overviews.cpp,v $
 * Revision 1.1  2005/09/17 03:47:41  fwarmerdam
 * New
 *
 */

#include "gdal_pam.h"
#include "hfa_p.h"
#include "cpl_string.h"

CPL_CVSID("$Id: hfa_overviews.cpp,v 1.1 2005/09/17 03:47:41 fwarmerdam Exp $");

CPLErr HFAAuxBuildOverviews( const char *pszOvrFilename, 
                             GDALDataset *poParentDS,
                             GDALDataset **ppoODS,
                             int nBands, int *panBandList,
                             int nNewOverviews, int *panNewOverviewList, 
                             const char *pszResampling, 
                             GDALProgressFunc pfnProgress, 
                             void *pProgressData )

{
/* ==================================================================== */
/*      If the .aux file doesn't exist yet then create it now.          */
/* ==================================================================== */
    if( *ppoODS == NULL )
    {
        GDALDataType eDT = GDT_Unknown;
/* -------------------------------------------------------------------- */
/*      Determine the band datatype, and verify that all bands are      */
/*      the same.                                                       */
/* -------------------------------------------------------------------- */
        int iBand;

        for( iBand = 0; iBand < nBands; iBand++ )
        {
            GDALRasterBand *poBand = 
                poParentDS->GetRasterBand( panBandList[iBand] );

            if( iBand == 0 )
                eDT = poBand->GetRasterDataType();
            else
            {
                if( eDT != poBand->GetRasterDataType() )
                {
                    CPLError( CE_Failure, CPLE_NotSupported, 
                              "HFAAuxBuildOverviews() doesn't support a mixture of band"
                              " data types." );
                    return CE_Failure;
                }
            }
        }

/* -------------------------------------------------------------------- */
/*      Create the HFA (.aux) file.  We create it with                  */
/*      COMPRESSED=YES so that no space will be allocated for the       */
/*      base band.                                                      */
/* -------------------------------------------------------------------- */
        GDALDriver *poHFADriver = (GDALDriver *) GDALGetDriverByName("HFA");
        char *apszOptions[3] = { "COMPRESSED=YES", 
                                 NULL, 
                                 NULL };
        
        CPLString osDepFileOpt = "DEPENDENT_FILE=";
        osDepFileOpt += CPLGetFilename(poParentDS->GetDescription());
        apszOptions[1] = (char *) osDepFileOpt.c_str();

        *ppoODS = 
            poHFADriver->Create( pszOvrFilename, 
                                 poParentDS->GetRasterXSize(), 
                                 poParentDS->GetRasterYSize(), 
                                 nBands, eDT, apszOptions );

        if( *ppoODS == NULL )
            return CE_Failure;
    }

/* ==================================================================== */
/*      Create the layers.  We depend on the normal buildoverviews      */
/*      support for HFA to do this.  But we disable the internal        */
/*      computation of the imagery for these layers.                    */
/*                                                                      */
/*      We avoid regenerating the new layers here, because if we did    */
/*      it would use the base layer from the .aux file as the source    */
/*      data, and that is fake (all invalid tiles).                     */
/* ==================================================================== */
    CPLString oAdjustedResampling = "NO_REGEN:";
    oAdjustedResampling += pszResampling;

    CPLErr eErr = 
        (*ppoODS)->BuildOverviews( oAdjustedResampling,
                                   nNewOverviews, panNewOverviewList,
                                   nBands, panBandList,
                                   pfnProgress, pProgressData );

    return eErr;
}