/******************************************************************************
 *
 * Project:  GDAL Rasterlite driver
 * Purpose:  Implement GDAL Rasterlite support using OGR SQLite driver
 * Author:   Even Rouault, <even dot rouault at spatialys.com>
 *
 **********************************************************************
 * Copyright (c) 2009-2012, Even Rouault <even dot rouault at spatialys.com>
 *
 * SPDX-License-Identifier: MIT
 ****************************************************************************/

#include "cpl_string.h"
#include "ogr_api.h"
#include "ogr_srs_api.h"
#include "memdataset.h"

#include "rasterlitedataset.h"

/************************************************************************/
/*                         ReloadOverviews()                            */
/************************************************************************/

CPLErr RasterliteDataset::ReloadOverviews()
{
    if (nLevel != 0)
        return CE_Failure;

    /* -------------------------------------------------------------------- */
    /*      Fetch resolutions                                               */
    /* -------------------------------------------------------------------- */

    CPLString osSQL;
    OGRLayerH hRasterPyramidsLyr =
        GDALDatasetGetLayerByName(hDS, "raster_pyramids");
    if (hRasterPyramidsLyr)
    {
        osSQL.Printf("SELECT pixel_x_size, pixel_y_size "
                     "FROM raster_pyramids WHERE table_prefix = '%s' "
                     "ORDER BY pixel_x_size ASC",
                     osTableName.c_str());
    }
    else
    {
        osSQL.Printf("SELECT DISTINCT(pixel_x_size), pixel_y_size "
                     "FROM \"%s_metadata\" WHERE pixel_x_size != 0  "
                     "ORDER BY pixel_x_size ASC",
                     osTableName.c_str());
    }

    OGRLayerH hSQLLyr =
        GDALDatasetExecuteSQL(hDS, osSQL.c_str(), nullptr, nullptr);
    if (hSQLLyr == nullptr)
    {
        if (hRasterPyramidsLyr == nullptr)
            return CE_Failure;

        osSQL.Printf("SELECT DISTINCT(pixel_x_size), pixel_y_size "
                     "FROM \"%s_metadata\" WHERE pixel_x_size != 0  "
                     "ORDER BY pixel_x_size ASC",
                     osTableName.c_str());

        hSQLLyr = GDALDatasetExecuteSQL(hDS, osSQL.c_str(), nullptr, nullptr);
        if (hSQLLyr == nullptr)
            return CE_Failure;
    }

    /* -------------------------------------------------------------------- */
    /*      Cleanup                                                         */
    /* -------------------------------------------------------------------- */
    for (int i = 1; i < nResolutions; i++)
        delete papoOverviews[i - 1];
    CPLFree(papoOverviews);
    papoOverviews = nullptr;
    CPLFree(padfXResolutions);
    padfXResolutions = nullptr;
    CPLFree(padfYResolutions);
    padfYResolutions = nullptr;

    /* -------------------------------------------------------------------- */
    /*      Rebuild arrays                                                  */
    /* -------------------------------------------------------------------- */

    nResolutions = static_cast<int>(OGR_L_GetFeatureCount(hSQLLyr, TRUE));

    padfXResolutions =
        reinterpret_cast<double *>(CPLMalloc(sizeof(double) * nResolutions));
    padfYResolutions =
        reinterpret_cast<double *>(CPLMalloc(sizeof(double) * nResolutions));

    {
        // Exstra scope for i.
        int i = 0;
        OGRFeatureH hFeat;
        while ((hFeat = OGR_L_GetNextFeature(hSQLLyr)) != nullptr)
        {
            padfXResolutions[i] = OGR_F_GetFieldAsDouble(hFeat, 0);
            padfYResolutions[i] = OGR_F_GetFieldAsDouble(hFeat, 1);

            OGR_F_Destroy(hFeat);

            i++;
        }
    }

    GDALDatasetReleaseResultSet(hDS, hSQLLyr);
    hSQLLyr = nullptr;

    /* -------------------------------------------------------------------- */
    /*      Add overview levels as internal datasets                        */
    /* -------------------------------------------------------------------- */
    if (nResolutions > 1)
    {
        CPLString osRasterTableName = osTableName;
        osRasterTableName += "_rasters";

        OGRLayerH hRasterLyr =
            GDALDatasetGetLayerByName(hDS, osRasterTableName.c_str());

        papoOverviews = reinterpret_cast<RasterliteDataset **>(
            CPLCalloc(nResolutions - 1, sizeof(RasterliteDataset *)));
        for (int nLev = 1; nLev < nResolutions; nLev++)
        {
            int nOvrBands;
            GDALDataType eOvrDataType;
            int nBlockXSize, nBlockYSize;
            if (GetBlockParams(hRasterLyr, nLev, &nOvrBands, &eOvrDataType,
                               &nBlockXSize, &nBlockYSize))
            {
                if (eOvrDataType == GDT_Byte && nOvrBands == 1 && nBands == 3)
                    nOvrBands = 3;

                papoOverviews[nLev - 1] = new RasterliteDataset(this, nLev);

                for (int iBand = 0; iBand < nBands; iBand++)
                {
                    papoOverviews[nLev - 1]->SetBand(
                        iBand + 1, new RasterliteBand(
                                       papoOverviews[nLev - 1], iBand + 1,
                                       eOvrDataType, nBlockXSize, nBlockYSize));
                }
            }
            else
            {
                CPLError(CE_Failure, CPLE_AppDefined,
                         "Cannot find block characteristics for overview %d",
                         nLev);
                papoOverviews[nLev - 1] = nullptr;
            }
        }
    }

    return CE_None;
}

/************************************************************************/
/*                          CleanOverviews()                            */
/************************************************************************/

CPLErr RasterliteDataset::CleanOverviews()
{
    if (nLevel != 0)
        return CE_Failure;

    CPLString osSQL("BEGIN");
    GDALDatasetExecuteSQL(hDS, osSQL.c_str(), nullptr, nullptr);

    const CPLString osResolutionCond =
        "NOT " +
        RasterliteGetPixelSizeCond(padfXResolutions[0], padfYResolutions[0]);

    osSQL.Printf("DELETE FROM \"%s_rasters\" WHERE id "
                 "IN(SELECT id FROM \"%s_metadata\" WHERE %s)",
                 osTableName.c_str(), osTableName.c_str(),
                 osResolutionCond.c_str());
    GDALDatasetExecuteSQL(hDS, osSQL.c_str(), nullptr, nullptr);

    osSQL.Printf("DELETE FROM \"%s_metadata\" WHERE %s", osTableName.c_str(),
                 osResolutionCond.c_str());
    GDALDatasetExecuteSQL(hDS, osSQL.c_str(), nullptr, nullptr);

    OGRLayerH hRasterPyramidsLyr =
        GDALDatasetGetLayerByName(hDS, "raster_pyramids");
    if (hRasterPyramidsLyr)
    {
        osSQL.Printf(
            "DELETE FROM raster_pyramids WHERE table_prefix = '%s' AND %s",
            osTableName.c_str(), osResolutionCond.c_str());
        GDALDatasetExecuteSQL(hDS, osSQL.c_str(), nullptr, nullptr);
    }

    osSQL = "COMMIT";
    GDALDatasetExecuteSQL(hDS, osSQL.c_str(), nullptr, nullptr);

    for (int i = 1; i < nResolutions; i++)
        delete papoOverviews[i - 1];
    CPLFree(papoOverviews);
    papoOverviews = nullptr;
    nResolutions = 1;

    return CE_None;
}

/************************************************************************/
/*                       CleanOverviewLevel()                           */
/************************************************************************/

CPLErr RasterliteDataset::CleanOverviewLevel(int nOvrFactor)
{
    if (nLevel != 0)
        return CE_Failure;

    /* -------------------------------------------------------------------- */
    /*      Find the index of the overview matching the overview factor     */
    /* -------------------------------------------------------------------- */
    int iLev = 1;
    for (; iLev < nResolutions; iLev++)
    {
        if (fabs(padfXResolutions[0] * nOvrFactor - padfXResolutions[iLev]) <
                1e-15 &&
            fabs(padfYResolutions[0] * nOvrFactor - padfYResolutions[iLev]) <
                1e-15)
            break;
    }

    if (iLev == nResolutions)
        return CE_None;

    /* -------------------------------------------------------------------- */
    /*      Now clean existing overviews at that resolution                 */
    /* -------------------------------------------------------------------- */

    CPLString osSQL("BEGIN");
    GDALDatasetExecuteSQL(hDS, osSQL.c_str(), nullptr, nullptr);

    CPLString osResolutionCond = RasterliteGetPixelSizeCond(
        padfXResolutions[iLev], padfYResolutions[iLev]);

    osSQL.Printf("DELETE FROM \"%s_rasters\" WHERE id "
                 "IN(SELECT id FROM \"%s_metadata\" WHERE %s)",
                 osTableName.c_str(), osTableName.c_str(),
                 osResolutionCond.c_str());
    GDALDatasetExecuteSQL(hDS, osSQL.c_str(), nullptr, nullptr);

    osSQL.Printf("DELETE FROM \"%s_metadata\" WHERE %s", osTableName.c_str(),
                 osResolutionCond.c_str());
    GDALDatasetExecuteSQL(hDS, osSQL.c_str(), nullptr, nullptr);

    OGRLayerH hRasterPyramidsLyr =
        GDALDatasetGetLayerByName(hDS, "raster_pyramids");
    if (hRasterPyramidsLyr)
    {
        osSQL.Printf(
            "DELETE FROM raster_pyramids WHERE table_prefix = '%s' AND %s",
            osTableName.c_str(), osResolutionCond.c_str());
        GDALDatasetExecuteSQL(hDS, osSQL.c_str(), nullptr, nullptr);
    }

    osSQL = "COMMIT";
    GDALDatasetExecuteSQL(hDS, osSQL.c_str(), nullptr, nullptr);

    return CE_None;
}

/************************************************************************/
/*                       CleanOverviewLevel()                           */
/************************************************************************/

CPLErr RasterliteDataset::CreateOverviewLevel(const char *pszResampling,
                                              int nOvrFactor,
                                              CSLConstList papszOptions,
                                              GDALProgressFunc pfnProgress,
                                              void *pProgressData)
{
    const int nOvrXSize = nRasterXSize / nOvrFactor;
    const int nOvrYSize = nRasterYSize / nOvrFactor;

    if (nOvrXSize == 0 || nOvrYSize == 0)
        return CE_Failure;

    const bool bTiled =
        CPLTestBool(CSLFetchNameValueDef(papszOptions, "TILED", "YES"));
    int nBlockXSize, nBlockYSize;
    if (bTiled)
    {
        nBlockXSize =
            atoi(CSLFetchNameValueDef(papszOptions, "BLOCKXSIZE", "256"));
        nBlockYSize =
            atoi(CSLFetchNameValueDef(papszOptions, "BLOCKYSIZE", "256"));
        if (nBlockXSize < 64)
            nBlockXSize = 64;
        else if (nBlockXSize > 4096)
            nBlockXSize = 4096;
        if (nBlockYSize < 64)
            nBlockYSize = 64;
        else if (nBlockYSize > 4096)
            nBlockYSize = 4096;
    }
    else
    {
        nBlockXSize = nOvrXSize;
        nBlockYSize = nOvrYSize;
    }

    const char *pszDriverName =
        CSLFetchNameValueDef(papszOptions, "DRIVER", "GTiff");
    if (EQUAL(pszDriverName, "MEM") || EQUAL(pszDriverName, "VRT"))
    {
        CPLError(CE_Failure, CPLE_AppDefined,
                 "GDAL %s driver cannot be used as underlying driver",
                 pszDriverName);
        return CE_Failure;
    }
    GDALDriverH hTileDriver = GDALGetDriverByName(pszDriverName);
    if (hTileDriver == nullptr)
    {
        CPLError(CE_Failure, CPLE_AppDefined, "Cannot load GDAL %s driver",
                 pszDriverName);
        return CE_Failure;
    }

    GDALDriverH hMemDriver = GDALGetDriverByName("MEM");
    if (hMemDriver == nullptr)
    {
        CPLError(CE_Failure, CPLE_AppDefined, "Cannot load GDAL MEM driver");
        return CE_Failure;
    }

    const GDALDataType eDataType = GetRasterBand(1)->GetRasterDataType();
    int nDataTypeSize = GDALGetDataTypeSize(eDataType) / 8;
    GByte *pabyMEMDSBuffer = reinterpret_cast<GByte *>(VSIMalloc3(
        nBlockXSize, nBlockYSize, cpl::fits_on<int>(nBands * nDataTypeSize)));
    if (pabyMEMDSBuffer == nullptr)
    {
        return CE_Failure;
    }

    const CPLString osTempFileName(
        VSIMemGenerateHiddenFilename("rasterlite_tile"));

    int nTileId = 0;
    int nBlocks = 0;

    const int nXBlocks = (nOvrXSize + nBlockXSize - 1) / nBlockXSize;
    const int nYBlocks = (nOvrYSize + nBlockYSize - 1) / nBlockYSize;
    int nTotalBlocks = nXBlocks * nYBlocks;

    CPLString osRasterLayer;
    osRasterLayer.Printf("%s_rasters", osTableName.c_str());

    CPLString osMetatadataLayer;
    osMetatadataLayer.Printf("%s_metadata", osTableName.c_str());

    OGRLayerH hRasterLayer =
        GDALDatasetGetLayerByName(hDS, osRasterLayer.c_str());
    OGRLayerH hMetadataLayer =
        GDALDatasetGetLayerByName(hDS, osMetatadataLayer.c_str());

    CPLString osSourceName = "unknown";

    const double dfXResolution = padfXResolutions[0] * nOvrFactor;
    const double dfYResolution = padfXResolutions[0] * nOvrFactor;

    CPLString osSQL;
    osSQL.Printf(
        "SELECT source_name FROM \"%s\" WHERE "
        "%s LIMIT 1",
        osMetatadataLayer.c_str(),
        RasterliteGetPixelSizeCond(padfXResolutions[0], padfYResolutions[0])
            .c_str());
    OGRLayerH hSQLLyr =
        GDALDatasetExecuteSQL(hDS, osSQL.c_str(), nullptr, nullptr);
    if (hSQLLyr)
    {
        OGRFeatureH hFeat = OGR_L_GetNextFeature(hSQLLyr);
        if (hFeat)
        {
            const char *pszVal = OGR_F_GetFieldAsString(hFeat, 0);
            if (pszVal)
                osSourceName = pszVal;
            OGR_F_Destroy(hFeat);
        }
        GDALDatasetReleaseResultSet(hDS, hSQLLyr);
    }

    /* -------------------------------------------------------------------- */
    /*      Compute up to which existing overview level we can use for      */
    /*      computing the requested overview                                */
    /* -------------------------------------------------------------------- */
    nLimitOvrCount = 0;
    int iLev = 1;
    for (; iLev < nResolutions; iLev++)
    {
        if (!(padfXResolutions[iLev] < dfXResolution - 1e-10 &&
              padfYResolutions[iLev] < dfYResolution - 1e-10))
        {
            break;
        }
        nLimitOvrCount++;
    }
    /* -------------------------------------------------------------------- */
    /*      Allocate buffer for tile of previous overview level             */
    /* -------------------------------------------------------------------- */

    GDALDataset *poPrevOvrLevel =
        (papoOverviews != nullptr && iLev >= 2 && iLev <= nResolutions &&
         papoOverviews[iLev - 2])
            ? papoOverviews[iLev - 2]
            : this;
    const double dfRatioPrevOvr =
        static_cast<double>(poPrevOvrLevel->GetRasterBand(1)->GetXSize()) /
        nOvrXSize;
    const int nPrevOvrBlockXSize =
        static_cast<int>(nBlockXSize * dfRatioPrevOvr + 0.5);
    const int nPrevOvrBlockYSize =
        static_cast<int>(nBlockYSize * dfRatioPrevOvr + 0.5);
    GByte *pabyPrevOvrMEMDSBuffer = nullptr;

    if (!STARTS_WITH_CI(pszResampling, "NEAR"))
    {
        pabyPrevOvrMEMDSBuffer = reinterpret_cast<GByte *>(
            VSIMalloc3(nPrevOvrBlockXSize, nPrevOvrBlockYSize,
                       cpl::fits_on<int>(nBands * nDataTypeSize)));
        if (pabyPrevOvrMEMDSBuffer == nullptr)
        {
            VSIFree(pabyMEMDSBuffer);
            return CE_Failure;
        }
    }

    /* -------------------------------------------------------------------- */
    /*      Iterate over blocks to add data into raster and metadata tables */
    /* -------------------------------------------------------------------- */

    char **papszTileDriverOptions =
        RasterliteGetTileDriverOptions(papszOptions);

    GDALDatasetExecuteSQL(hDS, "BEGIN", nullptr, nullptr);

    CPLErr eErr = CE_None;
    for (int nBlockYOff = 0; eErr == CE_None && nBlockYOff < nYBlocks;
         nBlockYOff++)
    {
        for (int nBlockXOff = 0; eErr == CE_None && nBlockXOff < nXBlocks;
             nBlockXOff++)
        {
            std::unique_ptr<MEMDataset> poPrevOvrMemDS;

            /* --------------------------------------------------------------------
             */
            /*      Create in-memory tile */
            /* --------------------------------------------------------------------
             */
            int nReqXSize = nBlockXSize;
            int nReqYSize = nBlockYSize;
            if ((nBlockXOff + 1) * nBlockXSize > nOvrXSize)
                nReqXSize = nOvrXSize - nBlockXOff * nBlockXSize;
            if ((nBlockYOff + 1) * nBlockYSize > nOvrYSize)
                nReqYSize = nOvrYSize - nBlockYOff * nBlockYSize;

            if (pabyPrevOvrMEMDSBuffer != nullptr)
            {
                int nPrevOvrReqXSize =
                    static_cast<int>(nReqXSize * dfRatioPrevOvr + 0.5);
                int nPrevOvrReqYSize =
                    static_cast<int>(nReqYSize * dfRatioPrevOvr + 0.5);

                eErr = RasterIO(GF_Read, nBlockXOff * nBlockXSize * nOvrFactor,
                                nBlockYOff * nBlockYSize * nOvrFactor,
                                nReqXSize * nOvrFactor, nReqYSize * nOvrFactor,
                                pabyPrevOvrMEMDSBuffer, nPrevOvrReqXSize,
                                nPrevOvrReqYSize, eDataType, nBands, nullptr, 0,
                                0, 0, nullptr);

                if (eErr != CE_None)
                {
                    break;
                }

                poPrevOvrMemDS.reset(MEMDataset::Create("", nPrevOvrReqXSize,
                                                        nPrevOvrReqYSize, 0,
                                                        eDataType, nullptr));

                for (int iBand = 0; iBand < nBands; iBand++)
                {
                    auto hBand = MEMCreateRasterBandEx(
                        poPrevOvrMemDS.get(), iBand + 1,
                        pabyPrevOvrMEMDSBuffer + iBand * nDataTypeSize *
                                                     nPrevOvrReqXSize *
                                                     nPrevOvrReqYSize,
                        eDataType, 0, 0, false);
                    poPrevOvrMemDS->AddMEMBand(hBand);
                }
            }
            else
            {
                eErr = RasterIO(GF_Read, nBlockXOff * nBlockXSize * nOvrFactor,
                                nBlockYOff * nBlockYSize * nOvrFactor,
                                nReqXSize * nOvrFactor, nReqYSize * nOvrFactor,
                                pabyMEMDSBuffer, nReqXSize, nReqYSize,
                                eDataType, nBands, nullptr, 0, 0, 0, nullptr);
                if (eErr != CE_None)
                {
                    break;
                }
            }

            auto poMemDS = std::unique_ptr<MEMDataset>(MEMDataset::Create(
                "", nReqXSize, nReqYSize, 0, eDataType, nullptr));
            for (int iBand = 0; iBand < nBands; iBand++)
            {
                auto hBand = MEMCreateRasterBandEx(
                    poMemDS.get(), iBand + 1,
                    pabyMEMDSBuffer +
                        iBand * nDataTypeSize * nReqXSize * nReqYSize,
                    eDataType, 0, 0, false);
                poMemDS->AddMEMBand(hBand);
            }

            auto hMemDS = GDALDataset::ToHandle(poMemDS.get());
            if (poPrevOvrMemDS != nullptr)
            {
                for (int iBand = 0; iBand < nBands; iBand++)
                {
                    GDALRasterBandH hDstOvrBand =
                        GDALGetRasterBand(hMemDS, iBand + 1);

                    auto hPrevOvrMEMDS =
                        GDALDataset::ToHandle(poPrevOvrMemDS.get());
                    eErr = GDALRegenerateOverviews(
                        GDALGetRasterBand(hPrevOvrMEMDS, iBand + 1), 1,
                        &hDstOvrBand, pszResampling, nullptr, nullptr);
                    if (eErr != CE_None)
                        break;
                }

                poPrevOvrMemDS.reset();
            }

            GDALDatasetH hOutDS =
                GDALCreateCopy(hTileDriver, osTempFileName.c_str(), hMemDS,
                               FALSE, papszTileDriverOptions, nullptr, nullptr);

            poMemDS.reset();
            if (!hOutDS)
            {
                eErr = CE_Failure;
                break;
            }

            GDALClose(hOutDS);

            /* --------------------------------------------------------------------
             */
            /*      Insert new entry into raster table */
            /* --------------------------------------------------------------------
             */

            vsi_l_offset nDataLength;
            GByte *pabyData = VSIGetMemFileBuffer(osTempFileName.c_str(),
                                                  &nDataLength, FALSE);

            OGRFeatureH hFeat = OGR_F_Create(OGR_L_GetLayerDefn(hRasterLayer));
            OGR_F_SetFieldBinary(hFeat, 0, static_cast<int>(nDataLength),
                                 pabyData);

            if (OGR_L_CreateFeature(hRasterLayer, hFeat) != OGRERR_NONE)
                eErr = CE_Failure;
            /* Query raster ID to set it as the ID of the associated metadata */
            const int nRasterID = static_cast<int>(OGR_F_GetFID(hFeat));

            OGR_F_Destroy(hFeat);

            VSIUnlink(osTempFileName.c_str());
            if (eErr == CE_Failure)
                break;

            /* --------------------------------------------------------------------
             */
            /*      Insert new entry into metadata table */
            /* --------------------------------------------------------------------
             */

            hFeat = OGR_F_Create(OGR_L_GetLayerDefn(hMetadataLayer));
            OGR_F_SetFID(hFeat, nRasterID);
            OGR_F_SetFieldString(hFeat, 0, osSourceName);
            OGR_F_SetFieldInteger(hFeat, 1, nTileId++);
            OGR_F_SetFieldInteger(hFeat, 2, nReqXSize);
            OGR_F_SetFieldInteger(hFeat, 3, nReqYSize);
            OGR_F_SetFieldDouble(hFeat, 4, dfXResolution);
            OGR_F_SetFieldDouble(hFeat, 5, dfYResolution);

            const double minx =
                adfGeoTransform[0] + (nBlockXSize * nBlockXOff) * dfXResolution;
            const double maxx =
                adfGeoTransform[0] +
                (nBlockXSize * nBlockXOff + nReqXSize) * dfXResolution;
            const double maxy = adfGeoTransform[3] +
                                (nBlockYSize * nBlockYOff) * (-dfYResolution);
            const double miny =
                adfGeoTransform[3] +
                (nBlockYSize * nBlockYOff + nReqYSize) * (-dfYResolution);

            OGRGeometryH hRectangle = OGR_G_CreateGeometry(wkbPolygon);
            OGRGeometryH hLinearRing = OGR_G_CreateGeometry(wkbLinearRing);
            OGR_G_AddPoint_2D(hLinearRing, minx, miny);
            OGR_G_AddPoint_2D(hLinearRing, minx, maxy);
            OGR_G_AddPoint_2D(hLinearRing, maxx, maxy);
            OGR_G_AddPoint_2D(hLinearRing, maxx, miny);
            OGR_G_AddPoint_2D(hLinearRing, minx, miny);
            OGR_G_AddGeometryDirectly(hRectangle, hLinearRing);

            OGR_F_SetGeometryDirectly(hFeat, hRectangle);

            if (OGR_L_CreateFeature(hMetadataLayer, hFeat) != OGRERR_NONE)
                eErr = CE_Failure;
            OGR_F_Destroy(hFeat);

            nBlocks++;
            if (pfnProgress && !pfnProgress(1.0 * nBlocks / nTotalBlocks,
                                            nullptr, pProgressData))
                eErr = CE_Failure;
        }
    }

    nLimitOvrCount = -1;

    VSIUnlink(osTempFileName);
    VSIUnlink((osTempFileName + ".aux.xml").c_str());

    if (eErr == CE_None)
        GDALDatasetExecuteSQL(hDS, "COMMIT", nullptr, nullptr);
    else
        GDALDatasetExecuteSQL(hDS, "ROLLBACK", nullptr, nullptr);

    VSIFree(pabyMEMDSBuffer);
    VSIFree(pabyPrevOvrMEMDSBuffer);

    CSLDestroy(papszTileDriverOptions);
    papszTileDriverOptions = nullptr;

    /* -------------------------------------------------------------------- */
    /*      Update raster_pyramids table                                    */
    /* -------------------------------------------------------------------- */
    if (eErr != CE_None)
        return eErr;

    OGRLayerH hRasterPyramidsLyr =
        GDALDatasetGetLayerByName(hDS, "raster_pyramids");
    if (hRasterPyramidsLyr == nullptr)
    {
        osSQL.Printf("CREATE TABLE raster_pyramids ("
                     "table_prefix TEXT NOT NULL,"
                     "pixel_x_size DOUBLE NOT NULL,"
                     "pixel_y_size DOUBLE NOT NULL,"
                     "tile_count INTEGER NOT NULL)");
        GDALDatasetExecuteSQL(hDS, osSQL.c_str(), nullptr, nullptr);

        /* Re-open the DB to take into account the new tables*/
        GDALClose(hDS);

        hDS = RasterliteOpenSQLiteDB(osFileName.c_str(), GA_Update);

        hRasterPyramidsLyr = GDALDatasetGetLayerByName(hDS, "raster_pyramids");
        if (hRasterPyramidsLyr == nullptr)
            return CE_Failure;
    }
    OGRFeatureDefnH hFDefn = OGR_L_GetLayerDefn(hRasterPyramidsLyr);

    /* Insert base resolution into raster_pyramids if not already done */
    bool bHasBaseResolution = false;
    osSQL.Printf(
        "SELECT * FROM raster_pyramids WHERE "
        "table_prefix = '%s' AND %s",
        osTableName.c_str(),
        RasterliteGetPixelSizeCond(padfXResolutions[0], padfYResolutions[0])
            .c_str());
    hSQLLyr = GDALDatasetExecuteSQL(hDS, osSQL.c_str(), nullptr, nullptr);
    if (hSQLLyr)
    {
        OGRFeatureH hFeat = OGR_L_GetNextFeature(hSQLLyr);
        if (hFeat)
        {
            bHasBaseResolution = true;
            OGR_F_Destroy(hFeat);
        }
        GDALDatasetReleaseResultSet(hDS, hSQLLyr);
    }

    if (!bHasBaseResolution)
    {
        osSQL.Printf(
            "SELECT COUNT(*) FROM \"%s\" WHERE %s", osMetatadataLayer.c_str(),
            RasterliteGetPixelSizeCond(padfXResolutions[0], padfYResolutions[0])
                .c_str());

        int nBlocksMainRes = 0;

        hSQLLyr = GDALDatasetExecuteSQL(hDS, osSQL.c_str(), nullptr, nullptr);
        if (hSQLLyr)
        {
            OGRFeatureH hFeat = OGR_L_GetNextFeature(hSQLLyr);
            if (hFeat)
            {
                nBlocksMainRes = OGR_F_GetFieldAsInteger(hFeat, 0);
                OGR_F_Destroy(hFeat);
            }
            GDALDatasetReleaseResultSet(hDS, hSQLLyr);
        }

        OGRFeatureH hFeat = OGR_F_Create(hFDefn);
        OGR_F_SetFieldString(hFeat,
                             OGR_FD_GetFieldIndex(hFDefn, "table_prefix"),
                             osTableName.c_str());
        OGR_F_SetFieldDouble(hFeat,
                             OGR_FD_GetFieldIndex(hFDefn, "pixel_x_size"),
                             padfXResolutions[0]);
        OGR_F_SetFieldDouble(hFeat,
                             OGR_FD_GetFieldIndex(hFDefn, "pixel_y_size"),
                             padfYResolutions[0]);
        OGR_F_SetFieldInteger(hFeat, OGR_FD_GetFieldIndex(hFDefn, "tile_count"),
                              nBlocksMainRes);
        if (OGR_L_CreateFeature(hRasterPyramidsLyr, hFeat) != OGRERR_NONE)
            eErr = CE_Failure;
        OGR_F_Destroy(hFeat);
    }

    OGRFeatureH hFeat = OGR_F_Create(hFDefn);
    OGR_F_SetFieldString(hFeat, OGR_FD_GetFieldIndex(hFDefn, "table_prefix"),
                         osTableName.c_str());
    OGR_F_SetFieldDouble(hFeat, OGR_FD_GetFieldIndex(hFDefn, "pixel_x_size"),
                         dfXResolution);
    OGR_F_SetFieldDouble(hFeat, OGR_FD_GetFieldIndex(hFDefn, "pixel_y_size"),
                         dfYResolution);
    OGR_F_SetFieldInteger(hFeat, OGR_FD_GetFieldIndex(hFDefn, "tile_count"),
                          nTotalBlocks);
    if (OGR_L_CreateFeature(hRasterPyramidsLyr, hFeat) != OGRERR_NONE)
        eErr = CE_Failure;
    OGR_F_Destroy(hFeat);

    return eErr;
}

/************************************************************************/
/*                          IBuildOverviews()                           */
/************************************************************************/

CPLErr RasterliteDataset::IBuildOverviews(
    const char *pszResampling, int nOverviews, const int *panOverviewList,
    int nBandsIn, const int *panBandList, GDALProgressFunc pfnProgress,
    void *pProgressData, CSLConstList papszOptions)
{
    if (nLevel != 0)
    {
        CPLError(CE_Failure, CPLE_AppDefined,
                 "Overviews can only be computed on the base dataset");
        return CE_Failure;
    }

    if (osTableName.empty())
        return CE_Failure;

    /* -------------------------------------------------------------------- */
    /*      If we don't have read access, then create the overviews         */
    /*      externally.                                                     */
    /* -------------------------------------------------------------------- */
    if (GetAccess() != GA_Update)
    {
        CPLDebug("Rasterlite", "File open for read-only accessing, "
                               "creating overviews externally.");

        if (nResolutions != 1)
        {
            CPLError(CE_Failure, CPLE_NotSupported,
                     "Cannot add external overviews to a "
                     "dataset with internal overviews");
            return CE_Failure;
        }

        bCheckForExistingOverview = FALSE;
        CPLErr eErr = GDALDataset::IBuildOverviews(
            pszResampling, nOverviews, panOverviewList, nBandsIn, panBandList,
            pfnProgress, pProgressData, papszOptions);
        bCheckForExistingOverview = TRUE;
        return eErr;
    }

    /* -------------------------------------------------------------------- */
    /*      If zero overviews were requested, we need to clear all          */
    /*      existing overviews.                                             */
    /* -------------------------------------------------------------------- */
    if (nOverviews == 0)
    {
        return CleanOverviews();
    }

    if (nBandsIn != GetRasterCount())
    {
        CPLError(CE_Failure, CPLE_NotSupported,
                 "Generation of overviews in RASTERLITE only"
                 " supported when operating on all bands.\n"
                 "Operation failed.\n");
        return CE_Failure;
    }

    const char *pszOvrOptions =
        CPLGetConfigOption("RASTERLITE_OVR_OPTIONS", nullptr);
    const CPLStringList aosCreationOptions(
        pszOvrOptions ? CSLTokenizeString2(pszOvrOptions, ",", 0) : nullptr);
    GDALValidateCreationOptions(GetDriver(), aosCreationOptions.List());

    CPLErr eErr = CE_None;
    for (int i = 0; i < nOverviews && eErr == CE_None; i++)
    {
        if (panOverviewList[i] <= 1)
            continue;

        eErr = CleanOverviewLevel(panOverviewList[i]);
        if (eErr == CE_None)
            eErr = CreateOverviewLevel(pszResampling, panOverviewList[i],
                                       aosCreationOptions.List(), pfnProgress,
                                       pProgressData);

        ReloadOverviews();
    }

    return eErr;
}