/******************************************************************************
 *
 * Project:  WCS Client Driver
 * Purpose:  Implementation of RasterBand classes for WCS.
 * Author:   Frank Warmerdam, warmerdam@pobox.com
 *
 ******************************************************************************
 * Copyright (c) 2006, Frank Warmerdam
 * Copyright (c) 2008-2013, Even Rouault <even dot rouault at spatialys.com>
 *
 * SPDX-License-Identifier: MIT
 ****************************************************************************/

#include "cpl_http.h"
#include "gdal_pam.h"

#include <algorithm>

#include "wcsdataset.h"
#include "wcsrasterband.h"

/************************************************************************/
/*                           WCSRasterBand()                            */
/************************************************************************/

WCSRasterBand::WCSRasterBand(WCSDataset *poDSIn, int nBandIn, int iOverviewIn)
    : iOverview(iOverviewIn),
      nResFactor(1 << (iOverviewIn + 1)),  // iOverview == -1 is base layer
      poODS(poDSIn), nOverviewCount(0), papoOverviews(nullptr)
{
    poDS = poDSIn;
    nBand = nBandIn;

    eDataType = GDALGetDataTypeByName(
        CPLGetXMLValue(poDSIn->psService, "BandType", "Byte"));

    /* -------------------------------------------------------------------- */
    /*      Establish resolution reduction for this overview level.         */
    /* -------------------------------------------------------------------- */

    /* -------------------------------------------------------------------- */
    /*      Establish block size.                                           */
    /* -------------------------------------------------------------------- */
    nRasterXSize = poDS->GetRasterXSize() / nResFactor;
    nRasterYSize = poDS->GetRasterYSize() / nResFactor;

    nBlockXSize = atoi(CPLGetXMLValue(poDSIn->psService, "BlockXSize", "0"));
    nBlockYSize = atoi(CPLGetXMLValue(poDSIn->psService, "BlockYSize", "0"));

    if (nBlockXSize < 1)
    {
        if (nRasterXSize > 1800)
            nBlockXSize = 1024;
        else
            nBlockXSize = nRasterXSize;
    }

    if (nBlockYSize < 1)
    {
        if (nRasterYSize > 900)
            nBlockYSize = 512;
        else
            nBlockYSize = nRasterYSize;
    }

    /* -------------------------------------------------------------------- */
    /*      If this is the base layer, create the overview layers.          */
    /* -------------------------------------------------------------------- */
    if (iOverview == -1)
    {
        nOverviewCount =
            atoi(CPLGetXMLValue(poODS->psService, "OverviewCount", "-1"));
        if (nOverviewCount < 0)
        {
            for (nOverviewCount = 0; (std::max(nRasterXSize, nRasterYSize) /
                                      (1 << nOverviewCount)) > 900;
                 nOverviewCount++)
            {
            }
        }
        else if (nOverviewCount > 30)
        {
            /* There's no reason to have more than 30 overviews, because */
            /* 2^(30+1) overflows a int32 */
            nOverviewCount = 30;
        }

        papoOverviews =
            (WCSRasterBand **)CPLCalloc(nOverviewCount, sizeof(void *));

        for (int i = 0; i < nOverviewCount; i++)
            papoOverviews[i] = new WCSRasterBand(poODS, nBand, i);
    }
}

/************************************************************************/
/*                           ~WCSRasterBand()                           */
/************************************************************************/

WCSRasterBand::~WCSRasterBand()

{
    FlushCache(true);

    if (nOverviewCount > 0)
    {
        for (int i = 0; i < nOverviewCount; i++)
            delete papoOverviews[i];

        CPLFree(papoOverviews);
    }
}

/************************************************************************/
/*                             IReadBlock()                             */
/************************************************************************/

CPLErr WCSRasterBand::IReadBlock(int nBlockXOff, int nBlockYOff, void *pImage)

{
    CPLErr eErr;
    CPLHTTPResult *psResult = nullptr;

    // if INTERLEAVE is set to PIXEL, then we'll request all bands.
    // That is necessary at least with MapServer, which seems to often
    // return all bands instead of requested.
    // todo: in 2.0.1 the band list in this dataset may be user-defined

    int band_count = 1;
    if (EQUAL(CPLGetXMLValue(poODS->psService, "INTERLEAVE", ""), "PIXEL"))
    {
        band_count = 0;
    }

    eErr = poODS->GetCoverage(
        nBlockXOff * nBlockXSize * nResFactor,
        nBlockYOff * nBlockYSize * nResFactor, nBlockXSize * nResFactor,
        nBlockYSize * nResFactor, nBlockXSize, nBlockYSize, band_count, &nBand,
        nullptr, &psResult);
    if (eErr != CE_None)
        return eErr;

    /* -------------------------------------------------------------------- */
    /*      Try and open result as a dataset.                               */
    /* -------------------------------------------------------------------- */
    GDALDataset *poTileDS = poODS->GDALOpenResult(psResult);

    if (poTileDS == nullptr)
        return CE_Failure;

    /* -------------------------------------------------------------------- */
    /*      Verify configuration.                                           */
    /* -------------------------------------------------------------------- */
    if (poTileDS->GetRasterXSize() != nBlockXSize ||
        poTileDS->GetRasterYSize() != nBlockYSize)
    {
        CPLError(CE_Failure, CPLE_AppDefined,
                 "Returned tile does not match expected configuration.\n"
                 "Got %dx%d instead of %dx%d.",
                 poTileDS->GetRasterXSize(), poTileDS->GetRasterYSize(),
                 nBlockXSize, nBlockYSize);
        delete poTileDS;
        return CE_Failure;
    }

    if (band_count == 1 &&
        ((!poODS->osBandIdentifier.empty() &&
          poTileDS->GetRasterCount() != 1) ||
         (poODS->osBandIdentifier.empty() &&
          poTileDS->GetRasterCount() != poODS->GetRasterCount())))
    {
        CPLString msg;
        if (!poODS->osBandIdentifier.empty() && poTileDS->GetRasterCount() != 1)
        {
            msg.Printf("Got %d bands instead of one although the coverage has "
                       "band range type.\n",
                       poTileDS->GetRasterCount());
        }
        else
        {
            msg.Printf(
                "Response has %d bands while this dataset has %d bands.\n",
                poTileDS->GetRasterCount(), poODS->GetRasterCount());
        }
        CPLError(
            CE_Failure, CPLE_AppDefined,
            "Returned tile does not match expected band configuration.\n%s",
            msg.c_str());
        delete poTileDS;
        return CE_Failure;
    }

    /* -------------------------------------------------------------------- */
    /*      Process all bands of memory result, copying into pBuffer, or    */
    /*      pushing into cache for other bands.                             */
    /* -------------------------------------------------------------------- */
    int iBand;
    eErr = CE_None;

    for (iBand = 0; iBand < poTileDS->GetRasterCount() && eErr == CE_None;
         iBand++)
    {
        GDALRasterBand *poTileBand = poTileDS->GetRasterBand(iBand + 1);

        if (iBand + 1 == GetBand() ||
            (band_count == 1 && !poODS->osBandIdentifier.empty()))
        {
            eErr = poTileBand->RasterIO(GF_Read, 0, 0, nBlockXSize, nBlockYSize,
                                        pImage, nBlockXSize, nBlockYSize,
                                        eDataType, 0, 0, nullptr);
        }
        else
        {
            GDALRasterBand *poTargBand = poODS->GetRasterBand(iBand + 1);

            if (iOverview != -1)
                poTargBand = poTargBand->GetOverview(iOverview);

            GDALRasterBlock *poBlock =
                poTargBand->GetLockedBlockRef(nBlockXOff, nBlockYOff, TRUE);

            if (poBlock != nullptr)
            {
                eErr = poTileBand->RasterIO(GF_Read, 0, 0, nBlockXSize,
                                            nBlockYSize, poBlock->GetDataRef(),
                                            nBlockXSize, nBlockYSize, eDataType,
                                            0, 0, nullptr);
                poBlock->DropLock();
            }
            else
                eErr = CE_Failure;
        }
    }

    /* -------------------------------------------------------------------- */
    /*      Cleanup                                                         */
    /* -------------------------------------------------------------------- */
    delete poTileDS;

    poODS->FlushMemoryResult();

    return eErr;
}

/************************************************************************/
/*                             IRasterIO()                              */
/************************************************************************/

CPLErr WCSRasterBand::IRasterIO(GDALRWFlag eRWFlag, int nXOff, int nYOff,
                                int nXSize, int nYSize, void *pData,
                                int nBufXSize, int nBufYSize,
                                GDALDataType eBufType, GSpacing nPixelSpace,
                                GSpacing nLineSpace,
                                GDALRasterIOExtraArg *psExtraArg)

{
    if ((poODS->nMaxCols > 0 && poODS->nMaxCols < nBufXSize) ||
        (poODS->nMaxRows > 0 && poODS->nMaxRows < nBufYSize))
        return CE_Failure;

    if (poODS->TestUseBlockIO(nXOff, nYOff, nXSize, nYSize, nBufXSize,
                              nBufYSize))
        return GDALPamRasterBand::IRasterIO(
            eRWFlag, nXOff, nYOff, nXSize, nYSize, pData, nBufXSize, nBufYSize,
            eBufType, nPixelSpace, nLineSpace, psExtraArg);
    else
        return poODS->DirectRasterIO(eRWFlag, nXOff * nResFactor,
                                     nYOff * nResFactor, nXSize * nResFactor,
                                     nYSize * nResFactor, pData, nBufXSize,
                                     nBufYSize, eBufType, 1, &nBand,
                                     nPixelSpace, nLineSpace, 0, psExtraArg);
}

/************************************************************************/
/*                           GetNoDataValue()                           */
/************************************************************************/

double WCSRasterBand::GetNoDataValue(int *pbSuccess)

{
    const char *pszSV =
        CPLGetXMLValue(poODS->psService, "NoDataValue", nullptr);

    if (pszSV == nullptr)
        return GDALPamRasterBand::GetNoDataValue(pbSuccess);
    else
    {
        if (pbSuccess)
            *pbSuccess = TRUE;
        return CPLAtof(pszSV);
    }
}

/************************************************************************/
/*                          GetOverviewCount()                          */
/************************************************************************/

int WCSRasterBand::GetOverviewCount()

{
    return nOverviewCount;
}

/************************************************************************/
/*                            GetOverview()                             */
/************************************************************************/

GDALRasterBand *WCSRasterBand::GetOverview(int iOverviewIn)

{
    if (iOverviewIn < 0 || iOverviewIn >= nOverviewCount)
        return nullptr;
    else
        return papoOverviews[iOverviewIn];
}
