/******************************************************************************

 *

 * Project:  CPL - Common Portability Library

 * Purpose:  Implement VSI large file api for Alibaba Object Storage Service

 * Author:   Even Rouault, even.rouault at spatialys.com

 *

 ******************************************************************************

 * Copyright (c) 2017-2018, Even Rouault <even.rouault at spatialys.com>

 *

 * SPDX-License-Identifier: MIT

 ****************************************************************************/

#include "cpl_port.h"

#include "cpl_http.h"

#include "cpl_minixml.h"

#include "cpl_vsil_curl_priv.h"

#include "cpl_vsil_curl_class.h"

#include <errno.h>

#include <algorithm>

#include <set>

#include <map>

#include <memory>

#include "cpl_alibaba_oss.h"

#ifndef HAVE_CURL

void VSIInstallOSSFileHandler(void)

{

    // Not supported

}

#else

//! @cond Doxygen_Suppress

#ifndef DOXYGEN_SKIP

#define ENABLE_DEBUG 0

namespace cpl

{

/************************************************************************/

/*                         VSIOSSFSHandler                              */

/************************************************************************/

class VSIOSSFSHandler final : public IVSIS3LikeFSHandlerWithMultipartUpload

{

    CPL_DISALLOW_COPY_ASSIGN(VSIOSSFSHandler)

  protected:

    VSICurlHandle *CreateFileHandle(const char *pszFilename) override;

    std::string

    GetURLFromFilename(const std::string &osFilename) const override;

    const char *GetDebugKey() const override

    {

        return "OSS";

    }

    IVSIS3LikeHandleHelper *CreateHandleHelper(const char *pszURI,

                                               bool bAllowNoObject) override;

    std::string GetFSPrefix() const override

    {

        return "/vsioss/";

    }

    void ClearCache() override;

    VSIVirtualHandleUniquePtr

    CreateWriteHandle(const char *pszFilename,

                      CSLConstList papszOptions) override;

  public:

    VSIOSSFSHandler() = default;

    ~VSIOSSFSHandler() override;

    const char *GetOptions() override;

    char *GetSignedURL(const char *pszFilename,

                       CSLConstList papszOptions) override;

    std::string

    GetStreamingFilename(const std::string &osFilename) const override

    {

        return osFilename;

    }

    bool SupportsMultipartAbort() const override

    {

        return true;

    }

};

/************************************************************************/

/*                            VSIOSSHandle                              */

/************************************************************************/

class VSIOSSHandle final : public IVSIS3LikeHandle

{

    CPL_DISALLOW_COPY_ASSIGN(VSIOSSHandle)

    VSIOSSHandleHelper *m_poHandleHelper = nullptr;

  protected:

    struct curl_slist *

    GetCurlHeaders(const std::string &osVerb,

                   const struct curl_slist *psExistingHeaders) override;

    bool CanRestartOnError(const char *, const char *, bool) override;

  public:

    VSIOSSHandle(VSIOSSFSHandler *poFS, const char *pszFilename,

                 VSIOSSHandleHelper *poHandleHelper);

    ~VSIOSSHandle() override;

};

/************************************************************************/

/*                       ~VSIOSSFSHandler()                             */

/************************************************************************/

VSIOSSFSHandler::~VSIOSSFSHandler()

{

    VSIOSSFSHandler::ClearCache();

}

/************************************************************************/

/*                          CreateWriteHandle()                         */

/************************************************************************/

VSIVirtualHandleUniquePtr

VSIOSSFSHandler::CreateWriteHandle(const char *pszFilename,

                                   CSLConstList papszOptions)

{

    auto poHandleHelper =

        CreateHandleHelper(pszFilename + GetFSPrefix().size(), false);

    if (poHandleHelper == nullptr)

        return nullptr;

    auto poHandle = std::make_unique<VSIMultipartWriteHandle>(

        this, pszFilename, poHandleHelper, papszOptions);

    if (!poHandle->IsOK())

    {

        return nullptr;

    }

    return VSIVirtualHandleUniquePtr(poHandle.release());

}

/************************************************************************/

/*                            ClearCache()                              */

/************************************************************************/

void VSIOSSFSHandler::ClearCache()

{

    VSICurlFilesystemHandlerBase::ClearCache();

    VSIOSSUpdateParams::ClearCache();

}

/************************************************************************/

/*                           GetOptions()                               */

/************************************************************************/

const char *VSIOSSFSHandler::GetOptions()

{

    static std::string osOptions(

        std::string("<Options>") +

        "  <Option name='OSS_SECRET_ACCESS_KEY' type='string' "

        "description='Secret access key. To use with OSS_ACCESS_KEY_ID'/>"

        "  <Option name='OSS_ACCESS_KEY_ID' type='string' "

        "description='Access key id'/>"

        "  <Option name='OSS_ENDPOINT' type='string' "

        "description='Default endpoint' default='oss-us-east-1.aliyuncs.com'/>"

        "  <Option name='VSIOSS_CHUNK_SIZE' type='int' "

        "description='Size in MB for chunks of files that are uploaded. The"

        "default value of 50 MB allows for files up to 500 GB each' "

        "default='50' min='1' max='1000'/>" +

        VSICurlFilesystemHandlerBase::GetOptionsStatic() + "</Options>");

    return osOptions.c_str();

}

/************************************************************************/

/*                           GetSignedURL()                             */

/************************************************************************/

char *VSIOSSFSHandler::GetSignedURL(const char *pszFilename,

                                    CSLConstList papszOptions)

{

    if (!STARTS_WITH_CI(pszFilename, GetFSPrefix().c_str()))

        return nullptr;

    VSIOSSHandleHelper *poHandleHelper = VSIOSSHandleHelper::BuildFromURI(

        pszFilename + GetFSPrefix().size(), GetFSPrefix().c_str(), false,

        papszOptions);

    if (poHandleHelper == nullptr)

    {

        return nullptr;

    }

    std::string osRet(poHandleHelper->GetSignedURL(papszOptions));

    delete poHandleHelper;

    return CPLStrdup(osRet.c_str());

}

/************************************************************************/

/*                          CreateFileHandle()                          */

/************************************************************************/

VSICurlHandle *VSIOSSFSHandler::CreateFileHandle(const char *pszFilename)

{

    VSIOSSHandleHelper *poHandleHelper = VSIOSSHandleHelper::BuildFromURI(

        pszFilename + GetFSPrefix().size(), GetFSPrefix().c_str(), false);

    if (poHandleHelper)

    {

        return new VSIOSSHandle(this, pszFilename, poHandleHelper);

    }

    return nullptr;

}

/************************************************************************/

/*                          GetURLFromFilename()                        */

/************************************************************************/

std::string

VSIOSSFSHandler::GetURLFromFilename(const std::string &osFilename) const

{

    const std::string osFilenameWithoutPrefix =

        osFilename.substr(GetFSPrefix().size());

    auto poHandleHelper =

        std::unique_ptr<VSIOSSHandleHelper>(VSIOSSHandleHelper::BuildFromURI(

            osFilenameWithoutPrefix.c_str(), GetFSPrefix().c_str(), true));

    if (!poHandleHelper)

    {

        return std::string();

    }

    std::string osBaseURL(poHandleHelper->GetURL());

    if (!osBaseURL.empty() && osBaseURL.back() == '/')

        osBaseURL.pop_back();

    return osBaseURL;

}

/************************************************************************/

/*                          CreateHandleHelper()                        */

/************************************************************************/

IVSIS3LikeHandleHelper *VSIOSSFSHandler::CreateHandleHelper(const char *pszURI,

                                                            bool bAllowNoObject)

{

    return VSIOSSHandleHelper::BuildFromURI(pszURI, GetFSPrefix().c_str(),

                                            bAllowNoObject);

}

/************************************************************************/

/*                            VSIOSSHandle()                            */

/************************************************************************/

VSIOSSHandle::VSIOSSHandle(VSIOSSFSHandler *poFSIn, const char *pszFilename,

                           VSIOSSHandleHelper *poHandleHelper)

    : IVSIS3LikeHandle(poFSIn, pszFilename, poHandleHelper->GetURL().c_str()),

      m_poHandleHelper(poHandleHelper)

{

}

/************************************************************************/

/*                            ~VSIOSSHandle()                           */

/************************************************************************/

VSIOSSHandle::~VSIOSSHandle()

{

    delete m_poHandleHelper;

}

/************************************************************************/

/*                           GetCurlHeaders()                           */

/************************************************************************/

struct curl_slist *

VSIOSSHandle::GetCurlHeaders(const std::string &osVerb,

                             const struct curl_slist *psExistingHeaders)

{

    return m_poHandleHelper->GetCurlHeaders(osVerb, psExistingHeaders);

}

/************************************************************************/

/*                          CanRestartOnError()                         */

/************************************************************************/

bool VSIOSSHandle::CanRestartOnError(const char *pszErrorMsg,

                                     const char *pszHeaders, bool bSetError)

{

    if (m_poHandleHelper->CanRestartOnError(pszErrorMsg, pszHeaders, bSetError))

    {

        SetURL(m_poHandleHelper->GetURL().c_str());

        return true;

    }

    return false;

}

} /* end of namespace cpl */

#endif  // DOXYGEN_SKIP

//! @endcond

/************************************************************************/

/*                      VSIInstallOSSFileHandler()                      */

/************************************************************************/

/*!

 \brief Install /vsioss/ Alibaba Cloud Object Storage Service (OSS) file

 system handler (requires libcurl)

 \verbatim embed:rst

 See :ref:`/vsioss/ documentation <vsioss>`

 \endverbatim

 @since GDAL 2.3

 */

void VSIInstallOSSFileHandler(void)

{

    VSIFileManager::InstallHandler("/vsioss/", new cpl::VSIOSSFSHandler);

}

#endif /* HAVE_CURL */