/******************************************************************************
 *
 * Project:  MSSQL Spatial driver
 * Purpose:  Implements OGRMSSQLSpatialDataSource class..
 * Author:   Tamas Szekeres, szekerest at gmail.com
 *
 ******************************************************************************
 * Copyright (c) 2010, Tamas Szekeres
 * Copyright (c) 2010-2013, Even Rouault <even dot rouault at spatialys.com>
 *
 * SPDX-License-Identifier: MIT
 ****************************************************************************/

#include "ogr_mssqlspatial.h"

/************************************************************************/
/*                          OGRMSSQLSpatialDataSource()                 */
/************************************************************************/

OGRMSSQLSpatialDataSource::OGRMSSQLSpatialDataSource() : bDSUpdate(false)
{
    pszCatalog = nullptr;
    papoLayers = nullptr;
    nLayers = 0;

    poLayerInCopyMode = nullptr;

    nGeometryFormat = MSSQLGEOMETRY_NATIVE;
    pszConnection = nullptr;

    sMSSQLVersion.nMajor = 0;
    sMSSQLVersion.nMinor = 0;
    sMSSQLVersion.nBuild = 0;
    sMSSQLVersion.nRevision = 0;

    bUseGeometryColumns = CPLTestBool(
        CPLGetConfigOption("MSSQLSPATIAL_USE_GEOMETRY_COLUMNS", "YES"));
    bAlwaysOutputFid =
        CPLTestBool(CPLGetConfigOption("MSSQLSPATIAL_ALWAYS_OUTPUT_FID", "NO"));
    bListAllTables =
        CPLTestBool(CPLGetConfigOption("MSSQLSPATIAL_LIST_ALL_TABLES", "NO"));

    const char *nBCPSizeParam =
        CPLGetConfigOption("MSSQLSPATIAL_BCP_SIZE", nullptr);
    if (nBCPSizeParam != nullptr)
        nBCPSize = atoi(nBCPSizeParam);
    else
        nBCPSize = 1000;
#ifdef MSSQL_BCP_SUPPORTED
    bUseCopy = CPLTestBool(CPLGetConfigOption("MSSQLSPATIAL_USE_BCP", "TRUE"));
#else
    bUseCopy = FALSE;
#endif
    CPLDebug("MSSQLSpatial", "Use COPY/BCP: %d", bUseCopy);
}

/************************************************************************/
/*                         ~OGRMSSQLSpatialDataSource()                 */
/************************************************************************/

OGRMSSQLSpatialDataSource::~OGRMSSQLSpatialDataSource()

{
    for (int i = 0; i < nLayers; i++)
        delete papoLayers[i];

    CPLFree(papoLayers);

    CPLFree(pszCatalog);

    CPLFree(pszConnection);
}

/************************************************************************/
/*                      OGRMSSQLDecodeVersionString()                   */
/************************************************************************/

void OGRMSSQLSpatialDataSource::OGRMSSQLDecodeVersionString(MSSQLVer *psVersion,
                                                            const char *pszVer)
{
    while (*pszVer == ' ')
        pszVer++;

    const char *ptr = pszVer;
    // get Version string
    while (*ptr && *ptr != ' ')
        ptr++;
    GUInt32 iLen = static_cast<int>(ptr - pszVer);
    char szVer[20] = {};
    if (iLen > sizeof(szVer) - 1)
        iLen = sizeof(szVer) - 1;
    strncpy(szVer, pszVer, iLen);
    szVer[iLen] = '\0';

    ptr = pszVer = szVer;

    // get Major number
    while (*ptr && *ptr != '.')
        ptr++;
    iLen = static_cast<int>(ptr - pszVer);
    char szNum[20] = {};
    if (iLen > sizeof(szNum) - 1)
        iLen = sizeof(szNum) - 1;
    strncpy(szNum, pszVer, iLen);
    szNum[iLen] = '\0';
    psVersion->nMajor = atoi(szNum);

    if (*ptr == 0)
        return;
    pszVer = ++ptr;

    // get Minor number
    while (*ptr && *ptr != '.')
        ptr++;
    iLen = static_cast<int>(ptr - pszVer);
    if (iLen > sizeof(szNum) - 1)
        iLen = sizeof(szNum) - 1;
    strncpy(szNum, pszVer, iLen);
    szNum[iLen] = '\0';
    psVersion->nMinor = atoi(szNum);

    if (*ptr == 0)
        return;
    pszVer = ++ptr;

    // get Build number
    while (*ptr && *ptr != '.')
        ptr++;
    iLen = static_cast<int>(ptr - pszVer);
    if (iLen > sizeof(szNum) - 1)
        iLen = sizeof(szNum) - 1;
    strncpy(szNum, pszVer, iLen);
    szNum[iLen] = '\0';
    psVersion->nBuild = atoi(szNum);

    if (*ptr == 0)
        return;
    pszVer = ++ptr;

    // get Revision number
    while (*ptr && *ptr != '.')
        ptr++;
    iLen = static_cast<int>(ptr - pszVer);
    if (iLen > sizeof(szNum) - 1)
        iLen = sizeof(szNum) - 1;
    strncpy(szNum, pszVer, iLen);
    szNum[iLen] = '\0';
    psVersion->nRevision = atoi(szNum);
}

/************************************************************************/
/*                           TestCapability()                           */
/************************************************************************/

int OGRMSSQLSpatialDataSource::TestCapability(const char *pszCap)

{
#if (ODBCVER >= 0x0300)
    if (EQUAL(pszCap, ODsCTransactions))
        return TRUE;
#endif
    if (EQUAL(pszCap, ODsCCreateLayer) || EQUAL(pszCap, ODsCDeleteLayer))
        return TRUE;
    if (EQUAL(pszCap, ODsCRandomLayerWrite))
        return TRUE;
    if (EQUAL(pszCap, OLCFastGetExtent))
        return TRUE;
    else if (EQUAL(pszCap, ODsCCurveGeometries))
        return TRUE;
    else if (EQUAL(pszCap, ODsCMeasuredGeometries))
        return TRUE;
    else if (EQUAL(pszCap, ODsCZGeometries))
        return TRUE;
    else
        return FALSE;
}

/************************************************************************/
/*                              GetLayer()                              */
/************************************************************************/

OGRLayer *OGRMSSQLSpatialDataSource::GetLayer(int iLayer)

{
    if (iLayer < 0 || iLayer >= nLayers)
        return nullptr;
    else
        return papoLayers[iLayer];
}

/************************************************************************/
/*                           GetLayerByName()                           */
/************************************************************************/

OGRLayer *OGRMSSQLSpatialDataSource::GetLayerByName(const char *pszLayerName)

{
    if (!pszLayerName)
        return nullptr;

    char *pszTableName = nullptr;
    char *pszSchemaName = nullptr;

    const char *pszDotPos = strstr(pszLayerName, ".");
    if (pszDotPos != nullptr)
    {
        int length = static_cast<int>(pszDotPos - pszLayerName);
        pszSchemaName = (char *)CPLMalloc(length + 1);
        strncpy(pszSchemaName, pszLayerName, length);
        pszSchemaName[length] = '\0';
        pszTableName = CPLStrdup(pszDotPos + 1);  // skip "."
    }
    else
    {
        pszSchemaName = CPLStrdup("dbo");
        pszTableName = CPLStrdup(pszLayerName);
    }

    for (int iLayer = 0; iLayer < nLayers; iLayer++)
    {
        if (EQUAL(pszTableName, papoLayers[iLayer]->GetTableName()) &&
            EQUAL(pszSchemaName, papoLayers[iLayer]->GetSchemaName()))
        {
            CPLFree(pszSchemaName);
            CPLFree(pszTableName);
            return papoLayers[iLayer];
        }
    }

    CPLFree(pszSchemaName);
    CPLFree(pszTableName);

    return nullptr;
}

/************************************************************************/
/*                            DeleteLayer()                             */
/************************************************************************/

OGRErr OGRMSSQLSpatialDataSource::DeleteLayer(int iLayer)

{
    if (iLayer < 0 || iLayer >= nLayers)
        return OGRERR_FAILURE;

    EndCopy();

    /* -------------------------------------------------------------------- */
    /*      Blow away our OGR structures related to the layer.  This is     */
    /*      pretty dangerous if anything has a reference to this layer!     */
    /* -------------------------------------------------------------------- */
    const char *pszTableName = papoLayers[iLayer]->GetTableName();
    const char *pszSchemaName = papoLayers[iLayer]->GetSchemaName();

    CPLODBCStatement oStmt(&oSession);
    if (bUseGeometryColumns)
        oStmt.Appendf("DELETE FROM geometry_columns WHERE f_table_schema = "
                      "'%s' AND f_table_name = '%s'\n",
                      pszSchemaName, pszTableName);
    oStmt.Appendf("DROP TABLE [%s].[%s]", pszSchemaName, pszTableName);

    CPLDebug("MSSQLSpatial", "DeleteLayer(%s)", pszTableName);

    papoLayers[iLayer]->SetSpatialIndexFlag(FALSE);

    delete papoLayers[iLayer];
    memmove(papoLayers + iLayer, papoLayers + iLayer + 1,
            sizeof(void *) * (nLayers - iLayer - 1));
    nLayers--;

    /* -------------------------------------------------------------------- */
    /*      Remove from the database.                                       */
    /* -------------------------------------------------------------------- */

    int bInTransaction = oSession.IsInTransaction();
    if (!bInTransaction)
        oSession.BeginTransaction();

    if (!oStmt.ExecuteSQL())
    {
        CPLError(CE_Failure, CPLE_AppDefined, "Error deleting layer: %s",
                 GetSession()->GetLastError());

        if (!bInTransaction)
            oSession.RollbackTransaction();

        return OGRERR_FAILURE;
    }

    if (!bInTransaction)
        oSession.CommitTransaction();

    return OGRERR_NONE;
}

/************************************************************************/
/*                            CreateLayer()                             */
/************************************************************************/

OGRLayer *
OGRMSSQLSpatialDataSource::ICreateLayer(const char *pszLayerName,
                                        const OGRGeomFieldDefn *poGeomFieldDefn,
                                        CSLConstList papszOptions)

{
    char *pszTableName = nullptr;
    char *pszSchemaName = nullptr;
    const char *pszGeomType = nullptr;
    const char *pszGeomColumn = nullptr;
    int nCoordDimension = 3;
    char *pszFIDColumnName = nullptr;

    const auto eType = poGeomFieldDefn ? poGeomFieldDefn->GetType() : wkbNone;
    const auto poSRS =
        poGeomFieldDefn ? poGeomFieldDefn->GetSpatialRef() : nullptr;

    EndCopy();

    /* determine the dimension */
    if (eType == wkbFlatten(eType))
        nCoordDimension = 2;

    if (CSLFetchNameValue(papszOptions, "DIM") != nullptr)
        nCoordDimension = atoi(CSLFetchNameValue(papszOptions, "DIM"));

    int bExtractSchemaFromLayerName = CPLTestBool(CSLFetchNameValueDef(
        papszOptions, "EXTRACT_SCHEMA_FROM_LAYER_NAME", "YES"));

    /* MSSQL Schema handling:
       Extract schema name from input layer name or passed with -lco SCHEMA.
       Set layer name to "schema.table" or to "table" if schema is not
       specified
    */
    const char *pszDotPos = strstr(pszLayerName, ".");
    if (pszDotPos != nullptr && bExtractSchemaFromLayerName)
    {
        int length = static_cast<int>(pszDotPos - pszLayerName);
        pszSchemaName = (char *)CPLMalloc(length + 1);
        CPLAssert(pszSchemaName !=
                  nullptr); /* to make Coverity happy and not believe a
                               REVERSE_INULL is possible */
        strncpy(pszSchemaName, pszLayerName, length);
        pszSchemaName[length] = '\0';

        if (CPLFetchBool(papszOptions, "LAUNDER", true))
            pszTableName = LaunderName(pszDotPos + 1);  // skip "."
        else
            pszTableName = CPLStrdup(pszDotPos + 1);  // skip "."
    }
    else
    {
        if (CPLFetchBool(papszOptions, "LAUNDER", TRUE))
            pszTableName = LaunderName(pszLayerName);  // skip "."
        else
            pszTableName = CPLStrdup(pszLayerName);  // skip "."
    }

    if (CSLFetchNameValue(papszOptions, "SCHEMA") != nullptr)
    {
        CPLFree(pszSchemaName);
        pszSchemaName = CPLStrdup(CSLFetchNameValue(papszOptions, "SCHEMA"));
    }

    if (pszSchemaName == nullptr)
        pszSchemaName = CPLStrdup("dbo");

    /* -------------------------------------------------------------------- */
    /*      Do we already have this layer?  If so, should we blow it        */
    /*      away?                                                           */
    /* -------------------------------------------------------------------- */
    int iLayer;

    for (iLayer = 0; iLayer < nLayers; iLayer++)
    {
        if (EQUAL(pszTableName, papoLayers[iLayer]->GetTableName()) &&
            EQUAL(pszSchemaName, papoLayers[iLayer]->GetSchemaName()))
        {
            if (CSLFetchNameValue(papszOptions, "OVERWRITE") != nullptr &&
                !EQUAL(CSLFetchNameValue(papszOptions, "OVERWRITE"), "NO"))
            {
                CPLFree(pszSchemaName);
                pszSchemaName = CPLStrdup(papoLayers[iLayer]->GetSchemaName());

                DeleteLayer(iLayer);
            }
            else
            {
                CPLError(CE_Failure, CPLE_AppDefined,
                         "Layer %s already exists, CreateLayer failed.\n"
                         "Use the layer creation option OVERWRITE=YES to "
                         "replace it.",
                         pszLayerName);

                CPLFree(pszSchemaName);
                CPLFree(pszTableName);
                return nullptr;
            }
        }
    }

    /* -------------------------------------------------------------------- */
    /*      Handle the GEOM_TYPE option.                                    */
    /* -------------------------------------------------------------------- */
    if (eType != wkbNone)
    {
        pszGeomType = CSLFetchNameValue(papszOptions, "GEOM_TYPE");

        if (!pszGeomType)
            pszGeomType = "geometry";

        if (!EQUAL(pszGeomType, "geometry") && !EQUAL(pszGeomType, "geography"))
        {
            CPLError(CE_Failure, CPLE_AppDefined,
                     "FORMAT=%s not recognised or supported.", pszGeomType);

            CPLFree(pszSchemaName);
            CPLFree(pszTableName);
            return nullptr;
        }

        /* determine the geometry column name */
        pszGeomColumn = CSLFetchNameValue(papszOptions, "GEOMETRY_NAME");
        if (!pszGeomColumn)
            pszGeomColumn = CSLFetchNameValue(papszOptions, "GEOM_NAME");
        if (!pszGeomColumn)
            pszGeomColumn = "ogr_geometry";
    }
    const bool bGeomNullable =
        CPLFetchBool(papszOptions, "GEOMETRY_NULLABLE", true);

    /* -------------------------------------------------------------------- */
    /*      Initialize the metadata tables                                  */
    /* -------------------------------------------------------------------- */

    if (InitializeMetadataTables() != OGRERR_NONE)
    {
        CPLFree(pszSchemaName);
        CPLFree(pszTableName);
        return nullptr;
    }

    /* -------------------------------------------------------------------- */
    /*      Try to get the SRS Id of this spatial reference system,         */
    /*      adding to the srs table if needed.                              */
    /* -------------------------------------------------------------------- */
    int nSRSId = 0;

    if (CSLFetchNameValue(papszOptions, "SRID") != nullptr)
        nSRSId = atoi(CSLFetchNameValue(papszOptions, "SRID"));

    if (nSRSId == 0 && poSRS != nullptr)
        nSRSId = FetchSRSId(poSRS);

    /* -------------------------------------------------------------------- */
    /*      Create a new table and create a new entry in the geometry,      */
    /*      geometry_columns metadata table.                                */
    /* -------------------------------------------------------------------- */

    CPLODBCStatement oStmt(&oSession);

    if (eType != wkbNone && bUseGeometryColumns)
    {
        const char *pszGeometryType = OGRToOGCGeomType(eType);

        oStmt.Appendf(
            "DELETE FROM geometry_columns WHERE f_table_schema = '%s' "
            "AND f_table_name = '%s'\n",
            pszSchemaName, pszTableName);

        oStmt.Appendf("INSERT INTO [geometry_columns] ([f_table_catalog], "
                      "[f_table_schema] ,[f_table_name], "
                      "[f_geometry_column],[coord_dimension],[srid],[geometry_"
                      "type]) VALUES ('%s', '%s', '%s', '%s', %d, %d, '%s')\n",
                      pszCatalog, pszSchemaName, pszTableName, pszGeomColumn,
                      nCoordDimension, nSRSId, pszGeometryType);
    }

    if (!EQUAL(pszSchemaName, "dbo"))
    {
        // creating the schema if not exists
        oStmt.Appendf("IF NOT EXISTS (SELECT name from sys.schemas WHERE name "
                      "= '%s') EXEC sp_executesql N'CREATE SCHEMA [%s]'\n",
                      pszSchemaName, pszSchemaName);
    }

    /* determine the FID column name */
    const char *pszFIDColumnNameIn =
        CSLFetchNameValueDef(papszOptions, "FID", "ogr_fid");
    if (CPLFetchBool(papszOptions, "LAUNDER", TRUE))
        pszFIDColumnName = LaunderName(pszFIDColumnNameIn);
    else
        pszFIDColumnName = CPLStrdup(pszFIDColumnNameIn);

    const bool bFID64 = CPLFetchBool(papszOptions, "FID64", FALSE);
    const char *pszFIDType = bFID64 ? "bigint" : "int";

    if (eType == wkbNone)
    {
        oStmt.Appendf(
            "CREATE TABLE [%s].[%s] ([%s] [%s] IDENTITY(1,1) NOT NULL, "
            "CONSTRAINT [PK_%s] PRIMARY KEY CLUSTERED ([%s] ASC))",
            pszSchemaName, pszTableName, pszFIDColumnName, pszFIDType,
            pszTableName, pszFIDColumnName);
    }
    else
    {
        oStmt.Appendf(
            "CREATE TABLE [%s].[%s] ([%s] [%s] IDENTITY(1,1) NOT NULL, "
            "[%s] [%s] %s, CONSTRAINT [PK_%s] PRIMARY KEY CLUSTERED ([%s] "
            "ASC))",
            pszSchemaName, pszTableName, pszFIDColumnName, pszFIDType,
            pszGeomColumn, pszGeomType, bGeomNullable ? "NULL" : "NOT NULL",
            pszTableName, pszFIDColumnName);
    }

    CPLFree(pszFIDColumnName);

    int bInTransaction = oSession.IsInTransaction();
    if (!bInTransaction)
        oSession.BeginTransaction();

    if (!oStmt.ExecuteSQL())
    {
        CPLError(CE_Failure, CPLE_AppDefined,
                 "Error creating layer: %s When using the overwrite option and "
                 "the layer doesn't contain geometry column, you might require "
                 "to use the MSSQLSPATIAL_LIST_ALL_TABLES config option to get "
                 "the previous layer deleted before creating the new one.",
                 GetSession()->GetLastError());

        if (!bInTransaction)
            oSession.RollbackTransaction();

        return nullptr;
    }

    if (!bInTransaction)
        oSession.CommitTransaction();

    /* -------------------------------------------------------------------- */
    /*      Create the layer object.                                        */
    /* -------------------------------------------------------------------- */
    OGRMSSQLSpatialTableLayer *poLayer;

    poLayer = new OGRMSSQLSpatialTableLayer(this);

    if (bInTransaction)
        poLayer->SetLayerStatus(MSSQLLAYERSTATUS_INITIAL);
    else
        poLayer->SetLayerStatus(MSSQLLAYERSTATUS_CREATED);

    poLayer->SetLaunderFlag(CPLFetchBool(papszOptions, "LAUNDER", true));
    poLayer->SetPrecisionFlag(CPLFetchBool(papszOptions, "PRECISION", true));

    if (bUseCopy)
        poLayer->SetUseCopy(nBCPSize);

    const char *pszSI = CSLFetchNameValue(papszOptions, "SPATIAL_INDEX");
    int bCreateSpatialIndex = (pszSI == nullptr || CPLTestBool(pszSI));
    if (pszGeomColumn == nullptr)
        bCreateSpatialIndex = FALSE;

    poLayer->SetSpatialIndexFlag(bCreateSpatialIndex);

    const char *pszUploadGeometryFormat =
        CSLFetchNameValue(papszOptions, "UPLOAD_GEOM_FORMAT");
    if (pszUploadGeometryFormat)
    {
        if (STARTS_WITH_CI(pszUploadGeometryFormat, "wkb"))
            poLayer->SetUploadGeometryFormat(MSSQLGEOMETRY_WKB);
        else if (STARTS_WITH_CI(pszUploadGeometryFormat, "wkt"))
            poLayer->SetUploadGeometryFormat(MSSQLGEOMETRY_WKT);
    }

    char *pszWKT = nullptr;
    if (poSRS && poSRS->exportToWkt(&pszWKT) != OGRERR_NONE)
    {
        CPLFree(pszWKT);
        pszWKT = nullptr;
    }

    if (bFID64)
        poLayer->SetMetadataItem(OLMD_FID64, "YES");

    if (poLayer->Initialize(pszSchemaName, pszTableName, pszGeomColumn,
                            nCoordDimension, nSRSId, pszWKT,
                            eType) == CE_Failure)
    {
        CPLFree(pszSchemaName);
        CPLFree(pszTableName);
        CPLFree(pszWKT);
        return nullptr;
    }

    CPLFree(pszSchemaName);
    CPLFree(pszTableName);
    CPLFree(pszWKT);

    /* -------------------------------------------------------------------- */
    /*      Add layer to data source layer list.                            */
    /* -------------------------------------------------------------------- */
    papoLayers = (OGRMSSQLSpatialTableLayer **)CPLRealloc(
        papoLayers, sizeof(OGRMSSQLSpatialTableLayer *) * (nLayers + 1));

    papoLayers[nLayers++] = poLayer;

    return poLayer;
}

/************************************************************************/
/*                             OpenTable()                              */
/************************************************************************/

int OGRMSSQLSpatialDataSource::OpenTable(const char *pszSchemaName,
                                         const char *pszTableName,
                                         const char *pszGeomCol,
                                         int nCoordDimension, int nSRID,
                                         const char *pszSRText,
                                         OGRwkbGeometryType eType, bool bUpdate)
{
    /* -------------------------------------------------------------------- */
    /*      Create the layer object.                                        */
    /* -------------------------------------------------------------------- */
    OGRMSSQLSpatialTableLayer *poLayer = new OGRMSSQLSpatialTableLayer(this);

    if (poLayer->Initialize(pszSchemaName, pszTableName, pszGeomCol,
                            nCoordDimension, nSRID, pszSRText, eType))
    {
        delete poLayer;
        return FALSE;
    }
    poLayer->SetUpdate(bUpdate);

    if (bUseCopy)
        poLayer->SetUseCopy(nBCPSize);

    /* -------------------------------------------------------------------- */
    /*      Add layer to data source layer list.                            */
    /* -------------------------------------------------------------------- */
    papoLayers = (OGRMSSQLSpatialTableLayer **)CPLRealloc(
        papoLayers, sizeof(OGRMSSQLSpatialTableLayer *) * (nLayers + 1));
    papoLayers[nLayers++] = poLayer;

    return TRUE;
}

/************************************************************************/
/*                       GetLayerCount()                                */
/************************************************************************/

int OGRMSSQLSpatialDataSource::GetLayerCount()
{
    return nLayers;
}

/************************************************************************/
/*                       ParseValue()                                   */
/************************************************************************/

int OGRMSSQLSpatialDataSource::ParseValue(char **pszValue, char *pszSource,
                                          const char *pszKey, int nStart,
                                          int nNext, int nTerm, int bRemove)
{
    int nLen = static_cast<int>(strlen(pszKey));
    if ((*pszValue) == nullptr && nStart + nLen < nNext &&
        EQUALN(pszSource + nStart, pszKey, nLen))
    {
        *pszValue =
            (char *)CPLMalloc(sizeof(char) * (nNext - nStart - nLen + 1));
        strncpy(*pszValue, pszSource + nStart + nLen, nNext - nStart - nLen);
        (*pszValue)[nNext - nStart - nLen] = 0;

        if (bRemove)
        {
            // remove the value from the source string
            if (pszSource[nNext] == ';')
                memmove(pszSource + nStart, pszSource + nNext + 1,
                        nTerm - nNext);
            else
                memmove(pszSource + nStart, pszSource + nNext,
                        nTerm - nNext + 1);
        }
        return TRUE;
    }
    return FALSE;
}

/************************************************************************/
/*                                Open()                                */
/************************************************************************/

int OGRMSSQLSpatialDataSource::Open(const char *pszNewName, bool bUpdate,
                                    int bTestOpen)

{
    CPLAssert(nLayers == 0);

    if (!STARTS_WITH_CI(pszNewName, "MSSQL:"))
    {
        if (!bTestOpen)
            CPLError(CE_Failure, CPLE_AppDefined,
                     "%s does not conform to MSSSQLSpatial naming convention,"
                     " MSSQL:*\n",
                     pszNewName);
        return FALSE;
    }

    /* Determine if the connection string contains specific values */
    char *pszTableSpec = nullptr;
    char *pszGeometryFormat = nullptr;
    char *pszConnectionName = CPLStrdup(pszNewName + 6);
    char *pszDriver = nullptr;
    char *pszUID = nullptr;
    char *pszPWD = nullptr;
    int nCurrent, nNext, nTerm;
    nCurrent = nNext = nTerm = static_cast<int>(strlen(pszConnectionName));

    while (nCurrent > 0)
    {
        --nCurrent;
        if (pszConnectionName[nCurrent] == ';')
        {
            nNext = nCurrent;
            continue;
        }

        if (ParseValue(&pszCatalog, pszConnectionName, "database=", nCurrent,
                       nNext, nTerm, FALSE))
            continue;

        if (ParseValue(&pszTableSpec, pszConnectionName, "tables=", nCurrent,
                       nNext, nTerm, TRUE))
            continue;

        if (ParseValue(&pszDriver, pszConnectionName, "driver=", nCurrent,
                       nNext, nTerm, FALSE))
            continue;

        if (ParseValue(&pszUID, pszConnectionName, "uid=", nCurrent, nNext,
                       nTerm, FALSE))
            continue;

        if (ParseValue(&pszPWD, pszConnectionName, "pwd=", nCurrent, nNext,
                       nTerm, FALSE))
            continue;

        if (ParseValue(&pszGeometryFormat, pszConnectionName,
                       "geometryformat=", nCurrent, nNext, nTerm, TRUE))
        {
            if (STARTS_WITH_CI(pszGeometryFormat, "wkbzm"))
                nGeometryFormat = MSSQLGEOMETRY_WKBZM;
            else if (STARTS_WITH_CI(pszGeometryFormat, "wkb"))
                nGeometryFormat = MSSQLGEOMETRY_WKB;
            else if (STARTS_WITH_CI(pszGeometryFormat, "wkt"))
                nGeometryFormat = MSSQLGEOMETRY_WKT;
            else if (STARTS_WITH_CI(pszGeometryFormat, "native"))
                nGeometryFormat = MSSQLGEOMETRY_NATIVE;
            else
            {
                CPLError(CE_Failure, CPLE_AppDefined,
                         "Invalid geometry type specified: %s,"
                         " MSSQL:*\n",
                         pszGeometryFormat);

                CPLFree(pszTableSpec);
                CPLFree(pszGeometryFormat);
                CPLFree(pszConnectionName);
                CPLFree(pszDriver);
                CPLFree(pszUID);
                CPLFree(pszPWD);
                return FALSE;
            }

            CPLFree(pszGeometryFormat);
            pszGeometryFormat = nullptr;
            continue;
        }
    }

    /* Determine if the connection string contains the catalog portion */
    if (pszCatalog == nullptr)
    {
        CPLError(CE_Failure, CPLE_AppDefined,
                 "'%s' does not contain the 'database' portion\n", pszNewName);

        CPLFree(pszTableSpec);
        CPLFree(pszGeometryFormat);
        CPLFree(pszConnectionName);
        CPLFree(pszDriver);
        CPLFree(pszUID);
        CPLFree(pszPWD);
        return FALSE;
    }

    char **papszTableNames = nullptr;
    char **papszSchemaNames = nullptr;
    char **papszGeomColumnNames = nullptr;
    char **papszCoordDimensions = nullptr;
    char **papszSRIds = nullptr;
    char **papszSRTexts = nullptr;

    /* Determine if the connection string contains the TABLES portion */
    if (pszTableSpec != nullptr)
    {
        char **papszTableList;
        int i;

        papszTableList = CSLTokenizeString2(pszTableSpec, ",", 0);

        for (i = 0; i < CSLCount(papszTableList); i++)
        {
            char **papszQualifiedParts;

            // Get schema and table name
            papszQualifiedParts = CSLTokenizeString2(papszTableList[i], ".", 0);

            /* Find the geometry column name if specified */
            if (CSLCount(papszQualifiedParts) >= 1)
            {
                char *pszGeomColumnName = nullptr;
                char *pos = strchr(
                    papszQualifiedParts[CSLCount(papszQualifiedParts) - 1],
                    '(');
                if (pos != nullptr)
                {
                    *pos = '\0';
                    pszGeomColumnName = pos + 1;
                    int len = static_cast<int>(strlen(pszGeomColumnName));
                    if (len > 0)
                        pszGeomColumnName[len - 1] = '\0';
                }
                papszGeomColumnNames =
                    CSLAddString(papszGeomColumnNames,
                                 pszGeomColumnName ? pszGeomColumnName : "");
            }

            if (CSLCount(papszQualifiedParts) == 2)
            {
                papszSchemaNames =
                    CSLAddString(papszSchemaNames, papszQualifiedParts[0]);
                papszTableNames =
                    CSLAddString(papszTableNames, papszQualifiedParts[1]);
            }
            else if (CSLCount(papszQualifiedParts) == 1)
            {
                papszSchemaNames = CSLAddString(papszSchemaNames, "dbo");
                papszTableNames =
                    CSLAddString(papszTableNames, papszQualifiedParts[0]);
            }

            CSLDestroy(papszQualifiedParts);
        }

        CSLDestroy(papszTableList);
    }

    CPLFree(pszTableSpec);

    if (pszDriver == nullptr)
    {
        char *pszConnectionName2 = pszConnectionName;
#if SQLNCLI_VERSION == 11
        pszDriver = CPLStrdup("{SQL Server Native Client 11.0}");
#elif SQLNCLI_VERSION == 10
        pszDriver = CPLStrdup("{SQL Server Native Client 10.0}");
#elif MSODBCSQL_VERSION == 13
        pszDriver = CPLStrdup("{ODBC Driver 13 for SQL Server}");
#elif MSODBCSQL_VERSION == 17
        pszDriver = CPLStrdup("{ODBC Driver 17 for SQL Server}");
#elif MSODBCSQL_VERSION == 18
        pszDriver = CPLStrdup("{ODBC Driver 18 for SQL Server}");
#else
        pszDriver = CPLStrdup("{SQL Server}");
#endif
        pszConnectionName = CPLStrdup(
            CPLSPrintf("DRIVER=%s;%s", pszDriver, pszConnectionName2));
        CPLFree(pszConnectionName2);
    }

    CPLFree(pszDriver);

    if (pszUID == nullptr)
    {
        const char *pszUIDConst =
            CPLGetConfigOption("MSSQLSPATIAL_UID", nullptr);
        if (pszUIDConst)
            pszUID = CPLStrdup(pszUIDConst);
    }
    if (pszUID != nullptr)
    {
        char *pszConnectionName2 = pszConnectionName;
        pszConnectionName =
            CPLStrdup(CPLSPrintf("%s;UID=%s", pszConnectionName2, pszUID));
        CPLFree(pszConnectionName2);
    }
    if (pszPWD == nullptr)
    {
        const char *pszPWDConst =
            CPLGetConfigOption("MSSQLSPATIAL_PWD", nullptr);
        if (pszPWDConst)
            pszPWD = CPLStrdup(pszPWDConst);
    }
    if (pszPWD != nullptr)
    {
        char *pszConnectionName2 = pszConnectionName;
        pszConnectionName =
            CPLStrdup(CPLSPrintf("%s;PWD=%s", pszConnectionName2, pszPWD));
        CPLFree(pszConnectionName2);
    }

    CPLFree(pszUID);
    CPLFree(pszPWD);

    /* Initialize the SQL Server connection. */
    if (!oSession.EstablishSession(pszConnectionName, "", ""))
    {
        /* Get a list of the available drivers */
        HENV hEnv;
        if (SQL_SUCCEEDED(SQLAllocEnv(&hEnv)))
        {
            CPLString osDriverList;
            SQLUSMALLINT direction = SQL_FETCH_FIRST;
            SQLSMALLINT driver_ret;
            SQLSMALLINT attr_ret;
            SQLCHAR attr[256];
            SQLCHAR driver[256];
            while (SQL_SUCCEEDED(SQLDrivers(hEnv, direction, driver,
                                            sizeof(driver), &driver_ret, attr,
                                            sizeof(attr), &attr_ret)))
            {
                direction = SQL_FETCH_NEXT;
                osDriverList += CPLSPrintf("%s\n", driver);
            }

            CPLError(CE_Failure, CPLE_AppDefined,
                     "Unable to initialize connection to the server for %s,\n"
                     "%s\n"
                     "Try specifying the driver in the connection string from "
                     "the list of available drivers:\n"
                     "%s",
                     pszNewName, oSession.GetLastError(), osDriverList.c_str());
        }
        else
        {
            CPLError(CE_Failure, CPLE_AppDefined,
                     "Unable to initialize connection to the server for %s,\n"
                     "%s\n",
                     pszNewName, oSession.GetLastError());
        }

        if (hEnv != nullptr)
            SQLFreeEnv(hEnv);

        CSLDestroy(papszTableNames);
        CSLDestroy(papszSchemaNames);
        CSLDestroy(papszGeomColumnNames);
        CSLDestroy(papszCoordDimensions);
        CSLDestroy(papszSRIds);
        CSLDestroy(papszSRTexts);
        CPLFree(pszGeometryFormat);
        CPLFree(pszConnectionName);
        return FALSE;
    }

    /* -------------------------------------------------------------------- */
    /*      Find out SQLServer version                                      */
    /* -------------------------------------------------------------------- */
    if (true)
    {
        sMSSQLVersion.nMajor = -1;
        sMSSQLVersion.nMinor = -1;
        sMSSQLVersion.nBuild = -1;
        sMSSQLVersion.nRevision = -1;

        CPLODBCStatement oStmt(&oSession);

        /* Use join to make sure the existence of the referred column/table */
        oStmt.Append(
            "SELECT SERVERPROPERTY('ProductVersion') AS ProductVersion;");

        if (oStmt.ExecuteSQL())
        {
            while (oStmt.Fetch())
            {
                OGRMSSQLDecodeVersionString(&sMSSQLVersion,
                                            oStmt.GetColData(0));
            }
        }
    }

    char **papszTypes = nullptr;

    /* read metadata for the specified tables */
    if (papszTableNames != nullptr && bUseGeometryColumns)
    {
        for (int iTable = 0; papszTableNames[iTable] != nullptr; iTable++)
        {
            CPLODBCStatement oStmt(&oSession);

            /* Use join to make sure the existence of the referred column/table
             */
            oStmt.Appendf(
                "SELECT f_geometry_column, coord_dimension, g.srid, srtext, "
                "geometry_type FROM dbo.geometry_columns g JOIN "
                "INFORMATION_SCHEMA.COLUMNS ON f_table_schema = TABLE_SCHEMA "
                "and f_table_name = TABLE_NAME and f_geometry_column = "
                "COLUMN_NAME left outer join dbo.spatial_ref_sys s on g.srid = "
                "s.srid WHERE f_table_schema = '%s' AND f_table_name = '%s'",
                papszSchemaNames[iTable], papszTableNames[iTable]);

            if (oStmt.ExecuteSQL())
            {
                while (oStmt.Fetch())
                {
                    if (papszGeomColumnNames == nullptr)
                        papszGeomColumnNames = CSLAddString(
                            papszGeomColumnNames, oStmt.GetColData(0));
                    else if (*papszGeomColumnNames[iTable] == 0)
                    {
                        CPLFree(papszGeomColumnNames[iTable]);
                        papszGeomColumnNames[iTable] =
                            CPLStrdup(oStmt.GetColData(0));
                    }

                    papszCoordDimensions = CSLAddString(
                        papszCoordDimensions, oStmt.GetColData(1, "2"));
                    papszSRIds =
                        CSLAddString(papszSRIds, oStmt.GetColData(2, "0"));
                    papszSRTexts =
                        CSLAddString(papszSRTexts, oStmt.GetColData(3, ""));
                    papszTypes = CSLAddString(papszTypes,
                                              oStmt.GetColData(4, "GEOMETRY"));
                }
            }
            else
            {
                /* probably the table is missing at all */
                InitializeMetadataTables();
            }
        }
    }

    /* if requesting all user database table then this takes priority */
    if (papszTableNames == nullptr && bListAllTables)
    {
        CPLODBCStatement oStmt(&oSession);

        oStmt.Append(
            "select sys.schemas.name, sys.schemas.name + '.' + "
            "sys.objects.name, sys.columns.name from sys.columns join "
            "sys.types on sys.columns.system_type_id = "
            "sys.types.system_type_id and sys.columns.user_type_id = "
            "sys.types.user_type_id join sys.objects on sys.objects.object_id "
            "= sys.columns.object_id join sys.schemas on sys.objects.schema_id "
            "= sys.schemas.schema_id where (sys.types.name = 'geometry' or "
            "sys.types.name = 'geography') and (sys.objects.type = 'U' or "
            "sys.objects.type = 'V') union all select sys.schemas.name, "
            "sys.schemas.name + '.' + sys.objects.name, '' from sys.objects "
            "join sys.schemas on sys.objects.schema_id = sys.schemas.schema_id "
            "where not exists (select * from sys.columns sc1 join sys.types on "
            "sc1.system_type_id = sys.types.system_type_id where "
            "(sys.types.name = 'geometry' or sys.types.name = 'geography') and "
            "sys.objects.object_id = sc1.object_id) and (sys.objects.type = "
            "'U' or sys.objects.type = 'V')");

        if (oStmt.ExecuteSQL())
        {
            while (oStmt.Fetch())
            {
                papszSchemaNames =
                    CSLAddString(papszSchemaNames, oStmt.GetColData(0));
                papszTableNames =
                    CSLAddString(papszTableNames, oStmt.GetColData(1));
                papszGeomColumnNames =
                    CSLAddString(papszGeomColumnNames, oStmt.GetColData(2));
            }
        }
    }

    /* Determine the available tables if not specified. */
    if (papszTableNames == nullptr && bUseGeometryColumns)
    {
        CPLODBCStatement oStmt(&oSession);

        /* Use join to make sure the existence of the referred column/table */
        oStmt.Append("SELECT f_table_schema, f_table_name, f_geometry_column, "
                     "coord_dimension, g.srid, srtext, geometry_type FROM "
                     "dbo.geometry_columns g JOIN INFORMATION_SCHEMA.COLUMNS "
                     "ON f_table_schema = TABLE_SCHEMA and f_table_name = "
                     "TABLE_NAME and f_geometry_column = COLUMN_NAME left "
                     "outer join dbo.spatial_ref_sys s on g.srid = s.srid");

        if (oStmt.ExecuteSQL())
        {
            while (oStmt.Fetch())
            {
                papszSchemaNames =
                    CSLAddString(papszSchemaNames, oStmt.GetColData(0, "dbo"));
                papszTableNames =
                    CSLAddString(papszTableNames, oStmt.GetColData(1));
                papszGeomColumnNames =
                    CSLAddString(papszGeomColumnNames, oStmt.GetColData(2));
                papszCoordDimensions = CSLAddString(papszCoordDimensions,
                                                    oStmt.GetColData(3, "2"));
                papszSRIds = CSLAddString(papszSRIds, oStmt.GetColData(4, "0"));
                papszSRTexts =
                    CSLAddString(papszSRTexts, oStmt.GetColData(5, ""));
                papszTypes =
                    CSLAddString(papszTypes, oStmt.GetColData(6, "GEOMETRY"));
            }
        }
        else
        {
            /* probably the table is missing at all */
            InitializeMetadataTables();
        }
    }

    /* Query catalog for tables having geometry columns */
    if (papszTableNames == nullptr)
    {
        CPLODBCStatement oStmt(&oSession);

        oStmt.Append(
            "SELECT sys.schemas.name, sys.schemas.name + '.' + "
            "sys.objects.name, sys.columns.name from sys.columns join "
            "sys.types on sys.columns.system_type_id = "
            "sys.types.system_type_id and sys.columns.user_type_id = "
            "sys.types.user_type_id join sys.objects on sys.objects.object_id "
            "= sys.columns.object_id join sys.schemas on sys.objects.schema_id "
            "= sys.schemas.schema_id where (sys.types.name = 'geometry' or "
            "sys.types.name = 'geography') and (sys.objects.type = 'U' or "
            "sys.objects.type = 'V')");

        if (oStmt.ExecuteSQL())
        {
            while (oStmt.Fetch())
            {
                papszSchemaNames =
                    CSLAddString(papszSchemaNames, oStmt.GetColData(0));
                papszTableNames =
                    CSLAddString(papszTableNames, oStmt.GetColData(1));
                papszGeomColumnNames =
                    CSLAddString(papszGeomColumnNames, oStmt.GetColData(2));
            }
        }
    }

    int nSRId, nCoordDimension;
    OGRwkbGeometryType eType;

    for (int iTable = 0;
         papszTableNames != nullptr && papszTableNames[iTable] != nullptr;
         iTable++)
    {
        if (papszSRIds != nullptr)
            nSRId = atoi(papszSRIds[iTable]);
        else
            nSRId = 0;

        if (papszCoordDimensions != nullptr)
            nCoordDimension = atoi(papszCoordDimensions[iTable]);
        else
            nCoordDimension = 2;

        if (papszTypes != nullptr)
            eType = OGRFromOGCGeomType(papszTypes[iTable]);
        else
            eType = wkbUnknown;

        CPLAssert(papszGeomColumnNames && papszGeomColumnNames[iTable]);
        if (strlen(papszGeomColumnNames[iTable]) > 0)
            OpenTable(papszSchemaNames[iTable], papszTableNames[iTable],
                      papszGeomColumnNames[iTable], nCoordDimension, nSRId,
                      papszSRTexts ? papszSRTexts[iTable] : nullptr, eType,
                      bUpdate);
        else
            OpenTable(papszSchemaNames[iTable], papszTableNames[iTable],
                      nullptr, nCoordDimension, nSRId,
                      papszSRTexts ? papszSRTexts[iTable] : nullptr, wkbNone,
                      bUpdate);
    }

    CSLDestroy(papszTableNames);
    CSLDestroy(papszSchemaNames);
    CSLDestroy(papszGeomColumnNames);
    CSLDestroy(papszCoordDimensions);
    CSLDestroy(papszSRIds);
    CSLDestroy(papszSRTexts);
    CSLDestroy(papszTypes);

    CPLFree(pszGeometryFormat);

    CPLFree(pszConnection);
    pszConnection = pszConnectionName;

    bDSUpdate = bUpdate;

    return TRUE;
}

/************************************************************************/
/*                             ExecuteSQL()                             */
/************************************************************************/

OGRLayer *OGRMSSQLSpatialDataSource::ExecuteSQL(const char *pszSQLCommand,
                                                OGRGeometry *poSpatialFilter,
                                                const char *pszDialect)

{
    /* -------------------------------------------------------------------- */
    /*      Use generic implementation for recognized dialects              */
    /* -------------------------------------------------------------------- */
    if (IsGenericSQLDialect(pszDialect))
        return GDALDataset::ExecuteSQL(pszSQLCommand, poSpatialFilter,
                                       pszDialect);

    /* -------------------------------------------------------------------- */
    /*      Special case DELLAYER: command.                                 */
    /* -------------------------------------------------------------------- */
    if (STARTS_WITH_CI(pszSQLCommand, "DELLAYER:"))
    {
        const char *pszLayerName = pszSQLCommand + 9;

        while (*pszLayerName == ' ')
            pszLayerName++;

        OGRLayer *poLayer = GetLayerByName(pszLayerName);

        for (int iLayer = 0; iLayer < nLayers; iLayer++)
        {
            if (papoLayers[iLayer] == poLayer)
            {
                DeleteLayer(iLayer);
                break;
            }
        }
        return nullptr;
    }

    CPLDebug("MSSQLSpatial", "ExecuteSQL(%s) called.", pszSQLCommand);

    if (STARTS_WITH_CI(pszSQLCommand, "DROP SPATIAL INDEX ON "))
    {
        /* Handle command to drop a spatial index. */
        OGRMSSQLSpatialTableLayer *poLayer =
            new OGRMSSQLSpatialTableLayer(this);

        if (poLayer)
        {
            if (poLayer->Initialize(nullptr, pszSQLCommand + 22, nullptr, 0, 0,
                                    nullptr, wkbUnknown) != CE_None)
            {
                CPLError(CE_Failure, CPLE_AppDefined,
                         "Failed to initialize layer '%s'", pszSQLCommand + 22);
            }
            poLayer->DropSpatialIndex();
            delete poLayer;
        }
        return nullptr;
    }
    else if (STARTS_WITH_CI(pszSQLCommand, "CREATE SPATIAL INDEX ON "))
    {
        /* Handle command to create a spatial index. */
        OGRMSSQLSpatialTableLayer *poLayer =
            new OGRMSSQLSpatialTableLayer(this);

        if (poLayer)
        {
            if (poLayer->Initialize(nullptr, pszSQLCommand + 24, nullptr, 0, 0,
                                    nullptr, wkbUnknown) != CE_None)
            {
                CPLError(CE_Failure, CPLE_AppDefined,
                         "Failed to initialize layer '%s'", pszSQLCommand + 24);
            }
            poLayer->CreateSpatialIndex();
            delete poLayer;
        }
        return nullptr;
    }

    /* Execute the command natively */
    CPLODBCStatement *poStmt = new CPLODBCStatement(&oSession);
    poStmt->Append(pszSQLCommand);

    if (!poStmt->ExecuteSQL())
    {
        CPLError(CE_Failure, CPLE_AppDefined, "%s", oSession.GetLastError());
        delete poStmt;
        return nullptr;
    }

    /* -------------------------------------------------------------------- */
    /*      Are there result columns for this statement?                    */
    /* -------------------------------------------------------------------- */
    if (poStmt->GetColCount() == 0)
    {
        delete poStmt;
        CPLErrorReset();
        return nullptr;
    }

    /* -------------------------------------------------------------------- */
    /*      Create a results layer.  It will take ownership of the          */
    /*      statement.                                                      */
    /* -------------------------------------------------------------------- */

    OGRMSSQLSpatialSelectLayer *poLayer =
        new OGRMSSQLSpatialSelectLayer(this, poStmt);

    if (poSpatialFilter != nullptr)
        poLayer->SetSpatialFilter(poSpatialFilter);

    return poLayer;
}

/************************************************************************/
/*                          ReleaseResultSet()                          */
/************************************************************************/

void OGRMSSQLSpatialDataSource::ReleaseResultSet(OGRLayer *poLayer)

{
    delete poLayer;
}

/************************************************************************/
/*                            LaunderName()                             */
/************************************************************************/

char *OGRMSSQLSpatialDataSource::LaunderName(const char *pszSrcName)

{
    char *pszSafeName = CPLStrdup(pszSrcName);
    int i;

    for (i = 0; pszSafeName[i] != '\0'; i++)
    {
        pszSafeName[i] =
            (char)CPLTolower(static_cast<unsigned char>(pszSafeName[i]));
        if (pszSafeName[i] == '-' || pszSafeName[i] == '#')
            pszSafeName[i] = '_';
    }

    return pszSafeName;
}

/************************************************************************/
/*                      InitializeMetadataTables()                      */
/*                                                                      */
/*      Create the metadata tables (SPATIAL_REF_SYS and                 */
/*      GEOMETRY_COLUMNS).                                              */
/************************************************************************/

OGRErr OGRMSSQLSpatialDataSource::InitializeMetadataTables()

{
    if (bUseGeometryColumns)
    {
        CPLODBCStatement oStmt(&oSession);

        oStmt.Append(
            "IF OBJECT_ID(N'[geometry_columns]', N'U') IS NULL "
            "CREATE TABLE geometry_columns (f_table_catalog varchar(128) not "
            "null, "
            "f_table_schema varchar(128) not null, f_table_name varchar(256) "
            "not null, "
            "f_geometry_column varchar(256) not null, coord_dimension integer "
            "not null, "
            "srid integer not null, geometry_type varchar(30) not null, "
            "CONSTRAINT geometry_columns_pk PRIMARY KEY (f_table_catalog, "
            "f_table_schema, f_table_name, f_geometry_column));\n");

        oStmt.Append("IF OBJECT_ID(N'[spatial_ref_sys]', N'U') IS NULL "
                     "CREATE TABLE spatial_ref_sys (srid integer not null "
                     "PRIMARY KEY, auth_name varchar(256), auth_srid integer, "
                     "srtext varchar(2048), proj4text varchar(2048))");

        int bInTransaction = oSession.IsInTransaction();
        if (!bInTransaction)
            oSession.BeginTransaction();

        if (!oStmt.ExecuteSQL())
        {
            CPLError(CE_Failure, CPLE_AppDefined,
                     "Error initializing the metadata tables : %s",
                     GetSession()->GetLastError());

            if (!bInTransaction)
                oSession.RollbackTransaction();

            return OGRERR_FAILURE;
        }

        if (!bInTransaction)
            oSession.CommitTransaction();
    }

    return OGRERR_NONE;
}

/************************************************************************/
/*                              FetchSRS()                              */
/*                                                                      */
/*      Return a SRS corresponding to a particular id.  Note that       */
/*      reference counting should be honoured on the returned           */
/*      OGRSpatialReference, as handles may be cached.                  */
/************************************************************************/

OGRSpatialReference *OGRMSSQLSpatialDataSource::FetchSRS(int nId)

{
    if (nId <= 0)
        return nullptr;

    /* -------------------------------------------------------------------- */
    /*      First, we look through our SRID cache, is it there?             */
    /* -------------------------------------------------------------------- */
    auto oIter = m_oSRSCache.find(nId);
    if (oIter != m_oSRSCache.end())
    {
        return oIter->second.get();
    }

    EndCopy();

    /* -------------------------------------------------------------------- */
    /*      Try looking up in spatial_ref_sys table                         */
    /* -------------------------------------------------------------------- */
    if (bUseGeometryColumns)
    {
        CPLODBCStatement oStmt(GetSession());
        oStmt.Appendf("SELECT srtext FROM spatial_ref_sys WHERE srid = %d",
                      nId);

        if (oStmt.ExecuteSQL() && oStmt.Fetch())
        {
            if (oStmt.GetColData(0))
            {
                auto poSRS = std::unique_ptr<OGRSpatialReference,
                                             OGRSpatialReferenceReleaser>(
                    new OGRSpatialReference());
                poSRS->SetAxisMappingStrategy(OAMS_TRADITIONAL_GIS_ORDER);
                const char *pszWKT = oStmt.GetColData(0);
                if (poSRS->importFromWkt(pszWKT) == OGRERR_NONE)
                {
                    const char *pszAuthorityName =
                        poSRS->GetAuthorityName(nullptr);
                    const char *pszAuthorityCode =
                        poSRS->GetAuthorityCode(nullptr);
                    if (pszAuthorityName && pszAuthorityCode &&
                        EQUAL(pszAuthorityName, "EPSG"))
                    {
                        const int nCode = atoi(pszAuthorityCode);
                        poSRS->Clear();
                        poSRS->importFromEPSG(nCode);
                    }

                    return AddSRIDToCache(nId, std::move(poSRS));
                }
            }
        }
    }

    /* -------------------------------------------------------------------- */
    /*      Try looking up the EPSG list                                    */
    /* -------------------------------------------------------------------- */
    auto poSRS =
        std::unique_ptr<OGRSpatialReference, OGRSpatialReferenceReleaser>(
            new OGRSpatialReference());
    poSRS->SetAxisMappingStrategy(OAMS_TRADITIONAL_GIS_ORDER);
    if (poSRS->importFromEPSG(nId) == OGRERR_NONE)
    {
        return AddSRIDToCache(nId, std::move(poSRS));
    }

    return nullptr;
}

/************************************************************************/
/*                         AddSRIDToCache()                             */
/*                                                                      */
/*      Note: this will not add a reference on the poSRS object. Make   */
/*      sure it is freshly created, or add a reference yourself if not. */
/************************************************************************/

OGRSpatialReference *OGRMSSQLSpatialDataSource::AddSRIDToCache(
    int nId,
    std::unique_ptr<OGRSpatialReference, OGRSpatialReferenceReleaser> &&poSRS)
{
    /* -------------------------------------------------------------------- */
    /*      Add to the cache.                                               */
    /* -------------------------------------------------------------------- */
    auto oIter = m_oSRSCache.emplace(nId, std::move(poSRS)).first;
    return oIter->second.get();
}

/************************************************************************/
/*                             FetchSRSId()                             */
/*                                                                      */
/*      Fetch the id corresponding to an SRS, and if not found, add     */
/*      it to the table.                                                */
/************************************************************************/

int OGRMSSQLSpatialDataSource::FetchSRSId(const OGRSpatialReference *poSRS)

{
    char *pszWKT = nullptr;
    int nSRSId = 0;
    const char *pszAuthorityName;

    if (poSRS == nullptr)
        return 0;
    /* -------------------------------------------------------------------- */
    /*      First, we look through our SRID cache, is it there?             */
    /* -------------------------------------------------------------------- */
    for (const auto &pair : m_oSRSCache)
    {
        if (pair.second.get() == poSRS)
            return pair.first;
    }
    for (const auto &pair : m_oSRSCache)
    {
        if (pair.second != nullptr && pair.second->IsSame(poSRS))
            return pair.first;
    }

    OGRSpatialReference oSRS(*poSRS);
    // cppcheck-suppress uselessAssignmentPtrArg
    poSRS = nullptr;

    pszAuthorityName = oSRS.GetAuthorityName(nullptr);

    if (pszAuthorityName == nullptr || strlen(pszAuthorityName) == 0)
    {
        /* --------------------------------------------------------------------
         */
        /*      Try to identify an EPSG code */
        /* --------------------------------------------------------------------
         */
        oSRS.AutoIdentifyEPSG();

        pszAuthorityName = oSRS.GetAuthorityName(nullptr);
        if (pszAuthorityName != nullptr && EQUAL(pszAuthorityName, "EPSG"))
        {
            const char *pszAuthorityCode = oSRS.GetAuthorityCode(nullptr);
            if (pszAuthorityCode != nullptr && strlen(pszAuthorityCode) > 0)
            {
                /* Import 'clean' SRS */
                oSRS.importFromEPSG(atoi(pszAuthorityCode));

                pszAuthorityName = oSRS.GetAuthorityName(nullptr);
            }
        }
    }
    /* -------------------------------------------------------------------- */
    /*      Check whether the EPSG authority code is already mapped to a    */
    /*      SRS ID.                                                         */
    /* -------------------------------------------------------------------- */
    int nAuthorityCode = 0;
    if (pszAuthorityName != nullptr && EQUAL(pszAuthorityName, "EPSG"))
    {
        /* For the root authority name 'EPSG', the authority code
         * should always be integral
         */
        nAuthorityCode = atoi(oSRS.GetAuthorityCode(nullptr));

        CPLODBCStatement oStmt(&oSession);
        oStmt.Appendf("SELECT srid FROM spatial_ref_sys WHERE "
                      "auth_name = '%s' AND auth_srid = %d",
                      pszAuthorityName, nAuthorityCode);

        if (oStmt.ExecuteSQL() && oStmt.Fetch() && oStmt.GetColData(0))
        {
            nSRSId = atoi(oStmt.GetColData(0));
            if (nSRSId != 0)
            {
                std::unique_ptr<OGRSpatialReference,
                                OGRSpatialReferenceReleaser>
                    poCachedSRS(new OGRSpatialReference(oSRS));
                poCachedSRS->SetAxisMappingStrategy(OAMS_TRADITIONAL_GIS_ORDER);
                AddSRIDToCache(nSRSId, std::move(poCachedSRS));
            }
            return nSRSId;
        }
    }

    /* -------------------------------------------------------------------- */
    /*      Translate SRS to WKT.                                           */
    /* -------------------------------------------------------------------- */
    if (oSRS.exportToWkt(&pszWKT) != OGRERR_NONE)
    {
        CPLFree(pszWKT);
        return 0;
    }

    /* -------------------------------------------------------------------- */
    /*      Try to find in the existing table.                              */
    /* -------------------------------------------------------------------- */
    CPLODBCStatement oStmt(&oSession);

    oStmt.Append("SELECT srid FROM spatial_ref_sys WHERE srtext = ");
    OGRMSSQLAppendEscaped(&oStmt, pszWKT);

    /* -------------------------------------------------------------------- */
    /*      We got it!  Return it.                                          */
    /* -------------------------------------------------------------------- */
    if (oStmt.ExecuteSQL())
    {
        if (oStmt.Fetch() && oStmt.GetColData(0))
        {
            nSRSId = atoi(oStmt.GetColData(0));
            CPLFree(pszWKT);
            return nSRSId;
        }
    }
    else
    {
        /* probably the table is missing at all */
        if (InitializeMetadataTables() != OGRERR_NONE)
        {
            CPLFree(pszWKT);
            return 0;
        }
    }

    /* -------------------------------------------------------------------- */
    /*      Try adding the SRS to the SRS table.                            */
    /* -------------------------------------------------------------------- */
    char *pszProj4 = nullptr;
    if (oSRS.exportToProj4(&pszProj4) != OGRERR_NONE)
    {
        CPLFree(pszProj4);
        CPLFree(pszWKT);
        return 0;
    }

    /* -------------------------------------------------------------------- */
    /*      Check whether the auth_code can be used as srid.                */
    /* -------------------------------------------------------------------- */
    nSRSId = nAuthorityCode;

    oStmt.Clear();

    int bInTransaction = oSession.IsInTransaction();
    if (!bInTransaction)
        oSession.BeginTransaction();

    if (nAuthorityCode > 0)
    {
        oStmt.Appendf("SELECT srid FROM spatial_ref_sys where srid = %d",
                      nAuthorityCode);
        if (oStmt.ExecuteSQL() && oStmt.Fetch())
        {
            nSRSId = 0;
        }
    }

    /* -------------------------------------------------------------------- */
    /*      Get the current maximum srid in the srs table.                  */
    /* -------------------------------------------------------------------- */

    if (nSRSId == 0)
    {
        oStmt.Clear();
        oStmt.Append("SELECT COALESCE(MAX(srid) + 1, 32768) FROM "
                     "spatial_ref_sys where srid between 32768 and 65536");

        if (oStmt.ExecuteSQL() && oStmt.Fetch() && oStmt.GetColData(0))
        {
            nSRSId = atoi(oStmt.GetColData(0));
        }
    }

    if (nSRSId == 0)
    {
        /* unable to allocate srid */
        if (!bInTransaction)
            oSession.RollbackTransaction();
        CPLFree(pszProj4);
        CPLFree(pszWKT);
        return 0;
    }

    oStmt.Clear();
    if (nAuthorityCode > 0)
    {
        oStmt.Appendf("INSERT INTO spatial_ref_sys (srid, auth_srid, "
                      "auth_name, srtext, proj4text) "
                      "VALUES (%d, %d, ",
                      nSRSId, nAuthorityCode);
        OGRMSSQLAppendEscaped(&oStmt, pszAuthorityName);
        oStmt.Append(", ");
        OGRMSSQLAppendEscaped(&oStmt, pszWKT);
        oStmt.Append(", ");
        OGRMSSQLAppendEscaped(&oStmt, pszProj4);
        oStmt.Append(")");
    }
    else
    {
        oStmt.Appendf(
            "INSERT INTO spatial_ref_sys (srid,srtext,proj4text) VALUES (%d, ",
            nSRSId);
        OGRMSSQLAppendEscaped(&oStmt, pszWKT);
        oStmt.Append(", ");
        OGRMSSQLAppendEscaped(&oStmt, pszProj4);
        oStmt.Append(")");
    }

    /* Free everything that was allocated. */
    CPLFree(pszProj4);
    CPLFree(pszWKT);

    if (oStmt.ExecuteSQL())
    {
        if (!bInTransaction)
            oSession.CommitTransaction();
    }
    else
    {
        if (!bInTransaction)
            oSession.RollbackTransaction();
    }

    return nSRSId;
}

/************************************************************************/
/*                         StartTransaction()                           */
/*                                                                      */
/* Should only be called by user code. Not driver internals.            */
/************************************************************************/

OGRErr OGRMSSQLSpatialDataSource::StartTransaction(CPL_UNUSED int bForce)
{
    if (!oSession.BeginTransaction())
    {
        CPLError(CE_Failure, CPLE_AppDefined, "Failed to start transaction: %s",
                 oSession.GetLastError());
        return OGRERR_FAILURE;
    }

    return OGRERR_NONE;
}

/************************************************************************/
/*                         CommitTransaction()                          */
/*                                                                      */
/* Should only be called by user code. Not driver internals.            */
/************************************************************************/

OGRErr OGRMSSQLSpatialDataSource::CommitTransaction()
{
    if (!oSession.CommitTransaction())
    {
        CPLError(CE_Failure, CPLE_AppDefined,
                 "Failed to commit transaction: %s", oSession.GetLastError());

        for (int iLayer = 0; iLayer < nLayers; iLayer++)
        {
            if (papoLayers[iLayer]->GetLayerStatus() ==
                MSSQLLAYERSTATUS_INITIAL)
                papoLayers[iLayer]->SetLayerStatus(MSSQLLAYERSTATUS_DISABLED);
        }
        return OGRERR_FAILURE;
    }

    /* set the status for the newly created layers */
    for (int iLayer = 0; iLayer < nLayers; iLayer++)
    {
        if (papoLayers[iLayer]->GetLayerStatus() == MSSQLLAYERSTATUS_INITIAL)
            papoLayers[iLayer]->SetLayerStatus(MSSQLLAYERSTATUS_CREATED);
    }

    return OGRERR_NONE;
}

/************************************************************************/
/*                        RollbackTransaction()                         */
/*                                                                      */
/* Should only be called by user code. Not driver internals.            */
/************************************************************************/

OGRErr OGRMSSQLSpatialDataSource::RollbackTransaction()
{
    /* set the status for the newly created layers */
    for (int iLayer = 0; iLayer < nLayers; iLayer++)
    {
        if (papoLayers[iLayer]->GetLayerStatus() == MSSQLLAYERSTATUS_INITIAL)
            papoLayers[iLayer]->SetLayerStatus(MSSQLLAYERSTATUS_DISABLED);
    }

    if (!oSession.RollbackTransaction())
    {
        CPLError(CE_Failure, CPLE_AppDefined,
                 "Failed to roll back transaction: %s",
                 oSession.GetLastError());
        return OGRERR_FAILURE;
    }

    return OGRERR_NONE;
}

/************************************************************************/
/*                             StartCopy()                              */
/************************************************************************/

void OGRMSSQLSpatialDataSource::StartCopy(
    OGRMSSQLSpatialTableLayer *poMSSQLSpatialLayer)
{
    if (poLayerInCopyMode == poMSSQLSpatialLayer)
        return;
    EndCopy();
    poLayerInCopyMode = poMSSQLSpatialLayer;
    poLayerInCopyMode->StartCopy();
}

/************************************************************************/
/*                              EndCopy()                               */
/************************************************************************/

OGRErr OGRMSSQLSpatialDataSource::EndCopy()
{
    if (poLayerInCopyMode != nullptr)
    {
        OGRErr result = poLayerInCopyMode->EndCopy();
        poLayerInCopyMode = nullptr;

        return result;
    }
    else
        return OGRERR_NONE;
}
