/******************************************************************************
 *
 * Project:  OpenGIS Simple Features Reference Implementation
 * Purpose:  IO Redirection via VSI services for shp/dbf io.
 * Author:   Frank Warmerdam, warmerdam@pobox.com
 *
 ******************************************************************************
 * Copyright (c) 2007,  Frank Warmerdam
 * Copyright (c) 2009-2013, Even Rouault <even dot rouault at spatialys.com>
 *
 * SPDX-License-Identifier: MIT
 ****************************************************************************/

#include "shp_vsi.h"
#include "cpl_error.h"
#include "cpl_conv.h"
#include "cpl_vsi_error.h"
#include <limits.h>

#include "shapefil_private.h"

typedef struct
{
    VSILFILE *fp;
    char *pszFilename;
    int bEnforce2GBLimit;
    int bHasWarned2GB;
    SAOffset nCurOffset;
} OGRSHPDBFFile;

/************************************************************************/
/*                         VSI_SHP_OpenInternal()                       */
/************************************************************************/

static SAFile VSI_SHP_OpenInternal(const char *pszFilename,
                                   const char *pszAccess, int bEnforce2GBLimit)

{
    OGRSHPDBFFile *pFile;
    VSILFILE *fp = VSIFOpenExL(pszFilename, pszAccess, TRUE);
    if (fp == SHPLIB_NULLPTR)
        return SHPLIB_NULLPTR;
    pFile = static_cast<OGRSHPDBFFile *>(CPLCalloc(1, sizeof(OGRSHPDBFFile)));
    pFile->fp = fp;
    pFile->pszFilename = CPLStrdup(pszFilename);
    pFile->bEnforce2GBLimit = bEnforce2GBLimit;
    pFile->nCurOffset = 0;
    return reinterpret_cast<SAFile>(pFile);
}

/************************************************************************/
/*                            VSI_SHP_Open()                            */
/************************************************************************/

static SAFile VSI_SHP_Open(const char *pszFilename, const char *pszAccess,
                           void *userData)

{
    (void)userData;
    return VSI_SHP_OpenInternal(pszFilename, pszAccess, FALSE);
}

/************************************************************************/
/*                            VSI_SHP_Read()                            */
/************************************************************************/

static SAOffset VSI_SHP_Read(void *p, SAOffset size, SAOffset nmemb,
                             SAFile file)

{
    OGRSHPDBFFile *pFile = reinterpret_cast<OGRSHPDBFFile *>(file);
    SAOffset ret = static_cast<SAOffset>(VSIFReadL(
        p, static_cast<size_t>(size), static_cast<size_t>(nmemb), pFile->fp));
    pFile->nCurOffset += ret * size;
    return ret;
}

/************************************************************************/
/*                      VSI_SHP_WriteMoreDataOK()                       */
/************************************************************************/

int VSI_SHP_WriteMoreDataOK(SAFile file, SAOffset nExtraBytes)
{
    OGRSHPDBFFile *pFile = reinterpret_cast<OGRSHPDBFFile *>(file);
    if (pFile->nCurOffset + nExtraBytes > INT_MAX)
    {
        if (pFile->bEnforce2GBLimit)
        {
            CPLError(CE_Failure, CPLE_AppDefined,
                     "2GB file size limit reached for %s", pFile->pszFilename);
            return FALSE;
        }
        else if (!pFile->bHasWarned2GB)
        {
            pFile->bHasWarned2GB = TRUE;
            CPLError(CE_Warning, CPLE_AppDefined,
                     "2GB file size limit reached for %s. "
                     "Going on, but might cause compatibility issues with "
                     "third party software",
                     pFile->pszFilename);
        }
    }

    return TRUE;
}

/************************************************************************/
/*                           VSI_SHP_Write()                            */
/************************************************************************/

static SAOffset VSI_SHP_Write(const void *p, SAOffset size, SAOffset nmemb,
                              SAFile file)

{
    OGRSHPDBFFile *pFile = reinterpret_cast<OGRSHPDBFFile *>(file);
    SAOffset ret;
    if (!VSI_SHP_WriteMoreDataOK(file, size * nmemb))
        return 0;
    ret = static_cast<SAOffset>(VSIFWriteL(
        p, static_cast<size_t>(size), static_cast<size_t>(nmemb), pFile->fp));
    pFile->nCurOffset += ret * size;
    return ret;
}

/************************************************************************/
/*                            VSI_SHP_Seek()                            */
/************************************************************************/

static SAOffset VSI_SHP_Seek(SAFile file, SAOffset offset, int whence)

{
    OGRSHPDBFFile *pFile = reinterpret_cast<OGRSHPDBFFile *>(file);
    int ret = VSIFSeekL(pFile->fp, static_cast<vsi_l_offset>(offset), whence);
    if (whence == 0 && ret == 0)
        pFile->nCurOffset = offset;
    else
        pFile->nCurOffset = static_cast<SAOffset>(VSIFTellL(pFile->fp));
    return ret;
}

/************************************************************************/
/*                            VSI_SHP_Tell()                            */
/************************************************************************/

static SAOffset VSI_SHP_Tell(SAFile file)

{
    OGRSHPDBFFile *pFile = reinterpret_cast<OGRSHPDBFFile *>(file);
    return static_cast<SAOffset>(pFile->nCurOffset);
}

/************************************************************************/
/*                           VSI_SHP_Flush()                            */
/************************************************************************/

static int VSI_SHP_Flush(SAFile file)

{
    OGRSHPDBFFile *pFile = reinterpret_cast<OGRSHPDBFFile *>(file);
    return VSIFFlushL(pFile->fp);
}

/************************************************************************/
/*                           VSI_SHP_Close()                            */
/************************************************************************/

static int VSI_SHP_Close(SAFile file)

{
    OGRSHPDBFFile *pFile = reinterpret_cast<OGRSHPDBFFile *>(file);
    int ret = VSIFCloseL(pFile->fp);
    CPLFree(pFile->pszFilename);
    CPLFree(pFile);
    return ret;
}

/************************************************************************/
/*                              SADError()                              */
/************************************************************************/

static void VSI_SHP_Error(const char *message)

{
    CPLError(CE_Failure, CPLE_AppDefined, "%s", message);
}

/************************************************************************/
/*                           VSI_SHP_Remove()                           */
/************************************************************************/

static int VSI_SHP_Remove(const char *pszFilename, void *userData)

{
    (void)userData;
    return VSIUnlink(pszFilename);
}

/************************************************************************/
/*                        SASetupDefaultHooks()                         */
/************************************************************************/

void SASetupDefaultHooks(SAHooks *psHooks)

{
    psHooks->FOpen = VSI_SHP_Open;
    psHooks->FRead = VSI_SHP_Read;
    psHooks->FWrite = VSI_SHP_Write;
    psHooks->FSeek = VSI_SHP_Seek;
    psHooks->FTell = VSI_SHP_Tell;
    psHooks->FFlush = VSI_SHP_Flush;
    psHooks->FClose = VSI_SHP_Close;
    psHooks->Remove = VSI_SHP_Remove;

    psHooks->Error = VSI_SHP_Error;
    psHooks->Atof = CPLAtof;
    psHooks->pvUserData = SHPLIB_NULLPTR;
}

#ifndef SHP_VSI_ONLY_SETUP_HOOKS

/************************************************************************/
/*                         VSI_SHP_GetVSIL()                            */
/************************************************************************/

VSILFILE *VSI_SHP_GetVSIL(SAFile file)
{
    OGRSHPDBFFile *pFile = reinterpret_cast<OGRSHPDBFFile *>(file);
    return pFile->fp;
}

/************************************************************************/
/*                        VSI_SHP_GetFilename()                         */
/************************************************************************/

const char *VSI_SHP_GetFilename(SAFile file)
{
    OGRSHPDBFFile *pFile = reinterpret_cast<OGRSHPDBFFile *>(file);
    return pFile->pszFilename;
}

/************************************************************************/
/*                        VSI_SHP_Open2GBLimit()                        */
/************************************************************************/

static SAFile VSI_SHP_Open2GBLimit(const char *pszFilename,
                                   const char *pszAccess, void *userData)

{
    (void)userData;
    return VSI_SHP_OpenInternal(pszFilename, pszAccess, TRUE);
}

/************************************************************************/
/*                         VSI_SHP_GetHook()                            */
/************************************************************************/

static const SAHooks sOGRHook = {VSI_SHP_Open,  VSI_SHP_Read,   VSI_SHP_Write,
                                 VSI_SHP_Seek,  VSI_SHP_Tell,   VSI_SHP_Flush,
                                 VSI_SHP_Close, VSI_SHP_Remove, VSI_SHP_Error,
                                 CPLAtof,       nullptr};

static const SAHooks sOGRHook2GBLimit = {
    VSI_SHP_Open2GBLimit, VSI_SHP_Read,  VSI_SHP_Write, VSI_SHP_Seek,
    VSI_SHP_Tell,         VSI_SHP_Flush, VSI_SHP_Close, VSI_SHP_Remove,
    VSI_SHP_Error,        CPLAtof,       nullptr};

const SAHooks *VSI_SHP_GetHook(int b2GBLimit)
{
    return (b2GBLimit) ? &sOGRHook2GBLimit : &sOGRHook;
}

#endif