/***************************************************************************
 *   Copyright (c) 2019 Jean-Marie Verdun         jmverdun3@gmail.com      *
 *                                                                         *
 *   This file is part of the FreeCAD CAx development system.              *
 *                                                                         *
 *   This library is free software; you can redistribute it and/or         *
 *   modify it under the terms of the GNU Library General Public           *
 *   License as published by the Free Software Foundation; either          *
 *   version 2 of the License, or (at your option) any later version.      *
 *                                                                         *
 *   This library  is distributed in the hope that it will be useful,      *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
 *   GNU Library General Public License for more details.                  *
 *                                                                         *
 *   You should have received a copy of the GNU Library General Public     *
 *   License along with this library; see the file COPYING.LIB. If not,    *
 *   write to the Free Software Foundation, Inc., 59 Temple Place,         *
 *   Suite 330, Boston, MA  02111-1307, USA                                *
 *                                                                         *
 ***************************************************************************/

#include <App/Document.h>

#include <Base/Base64.h>
#include <Base/Interpreter.h>
#include <Base/Reader.h>
#include <Base/Writer.h>

#include <xercesc/framework/MemBufInputSource.hpp>
#include <xercesc/framework/XMLPScanToken.hpp>
#include <xercesc/parsers/XercesDOMParser.hpp>
#include <xercesc/dom/DOM.hpp>
#include <xercesc/sax/HandlerBase.hpp>
#include <xercesc/sax2/Attributes.hpp>
#include <xercesc/sax2/DefaultHandler.hpp>


XERCES_CPP_NAMESPACE_BEGIN
    class DOMNode;
    class DOMText;
XERCES_CPP_NAMESPACE_END

namespace Cloud {

struct AmzData {
	std::string digest;
	char dateFormatted[256];
	char ContentType[256];
	char Host[256];
	char *MD5;
};

struct AmzDatav4 {
        std::string digest;
        char dateFormattedS[256];
        char dateFormattedD[256];
        char ContentType[256];
        char Host[256];
	std::string Region;
        char *MD5;
	char *SHA256Sum;
};

std::string getHexValue(unsigned char *input, unsigned int HMACLength);
void eraseSubStr(std::string & Str, const std::string & toErase);
size_t CurlWrite_CallbackFunc_StdString(void *contents, size_t size, size_t nmemb, std::string *s);
struct AmzData *ComputeDigestAmzS3v2(char *operation, char *data_type, const char *target, const char *Secret, const char *ptr, long size);
struct AmzDatav4 *ComputeDigestAmzS3v4(char *operation, const char *server, char *data_type, const char *target, const char *Secret, const char *ptr, long size, char *parameters, std::string Region);
struct curl_slist *BuildHeaderAmzS3v2(const char *URL, const char *TCPPort, const char *PublicKey, struct AmzData *Data);
struct curl_slist *BuildHeaderAmzS3v4(const char *URL, const char *PublicKey, struct AmzDatav4 *Data);
char *MD5Sum(const char *ptr, long size);
char *SHA256Sum(const char *ptr, long size);

class CloudAppExport CloudReader
{
public:
    CloudReader(const char* URL, const char* AccessKey, const char* SecretKey, const char* TCPPort, const char* Bucket,std::string ProtocolVersion, std::string Region);
    virtual ~CloudReader();
    int file=0;
    int continuation=0;
    int truncated=0;

    struct FileEntry
    {
        char FileName[1024];
        std::stringstream FileStream;
        int touch=0;
    };
    void checkText(XERCES_CPP_NAMESPACE_QUALIFIER DOMText* text);
    void checkXML(XERCES_CPP_NAMESPACE_QUALIFIER DOMNode* node);
    void checkElement(XERCES_CPP_NAMESPACE_QUALIFIER DOMElement* element);
    void addFile(struct Cloud::CloudReader::FileEntry *new_entry);
    struct FileEntry *GetEntry(std::string FileName);
    void DownloadFile(Cloud::CloudReader::FileEntry *entry);
    int isTouched(std::string FileName);
protected:
    std::list<Cloud::CloudReader::FileEntry*> FileList;
    char* NextFileName;
    const char* URL;
    const char* TCPPort;
    const char* TokenAuth;
    const char* TokenSecret;
    const char* Bucket;
    std::string ProtocolVersion;
    std::string Region;
};

class Module : public Py::ExtensionModule<Module>
{
public:
    Module() : Py::ExtensionModule<Module>("Cloud")
    {
	add_varargs_method("URL",&Module::sCloudURL,
            "URL(string) -- Connect to a Cloud Storage service."
        );

	add_varargs_method("TokenAuth",&Module::sCloudTokenAuth,
            "TokenAuth(string) -- Token Authorization string."
        );

	add_varargs_method("TokenSecret",&Module::sCloudTokenSecret,
            "TokenSecret(string) -- Token Secret string."
        );
	
	add_varargs_method("TCPPort",&Module::sCloudTCPPort,
            "TCPPort(string) -- Port number."
        );

	add_varargs_method("Save",&Module::sCloudSave,
            "Save(string) -- Save the active document to the Cloud."
        );

        add_varargs_method("Restore",&Module::sCloudRestore,
            "Restore(string) -- Restore to the active document from the Cloud."
        );

	add_varargs_method("ProtocolVersion",&Module::sCloudProtocolVersion,
            "ProtocolVersion(string) -- Specify Amazon s3 protocol version (2 or 4)"
        );
	add_varargs_method("Region",&Module::sCloudRegion,
            "Region(string) -- Specify Amazon s3 Region"
        );

        initialize("This module is the Cloud module."); // register with Python
    }

    virtual ~Module() {}

    App::PropertyString URL;
    App::PropertyString TCPPort;
    App::PropertyString TokenAuth;
    App::PropertyString TokenSecret;
    App::PropertyString ProtocolVersion;
    App::PropertyString Region;
    bool cloudSave(const char* BucketName);
    bool cloudRestore(const char* BucketName);
    void LinkXSetValue(std::string filename);

private:
    Py::Object sCloudURL  (const Py::Tuple& args);
    Py::Object sCloudTokenAuth  (const Py::Tuple& args);
    Py::Object sCloudTokenSecret  (const Py::Tuple& args);
    Py::Object sCloudTCPPort  (const Py::Tuple& args);
    Py::Object sCloudSave  (const Py::Tuple& args);
    Py::Object sCloudRestore  (const Py::Tuple& args);
    Py::Object sCloudProtocolVersion  (const Py::Tuple& args);
    Py::Object sCloudRegion  (const Py::Tuple& args);


};

PyObject* initModule()
{
    return Base::Interpreter().addModule(new Module);
}


// This class is writing files to an S3 cloud storage class

class CloudAppExport CloudWriter : public Base::Writer
{
public:
    int print=0;
    char errorCode[1024]="";
    CloudWriter(const char* URL, const char* TokenAuth, const char* TokenSecret, const char* TCPPort, const char* Bucket, std::string ProtocolVersion, std::string Region);
    virtual ~CloudWriter();
    void pushCloud(const char *FileName, const char *data, long size);
    void putNextEntry(const char* file);
    void createBucket();
    virtual void writeFiles(void);

    virtual std::ostream &Stream(void){return FileStream;}
    virtual bool shouldWrite(const std::string& name, const Base::Persistence *Object) const;
    void checkText(XERCES_CPP_NAMESPACE_QUALIFIER DOMText* text);
    void checkXML(XERCES_CPP_NAMESPACE_QUALIFIER DOMNode* node);
    void checkElement(XERCES_CPP_NAMESPACE_QUALIFIER DOMElement* element);

protected:
    std::string FileName;
    const char* URL;
    const char* TCPPort;
    const char* TokenAuth;
    const char* TokenSecret;
    const char* Bucket;
    std::string ProtocolVersion;
    std::string Region;
    std::stringstream FileStream;
};


}

void readFiles(Cloud::CloudReader reader, Base::XMLReader *xmlreader);