// $Id$
//-----------------------------------------------------------------------
//       The GSI Online Offline Object Oriented (Go4) Project
//         Experiment Data Processing at EE department, GSI
//-----------------------------------------------------------------------
// Copyright (C) 2000- GSI Helmholtzzentrum fuer Schwerionenforschung GmbH
//                     Planckstr. 1, 64291 Darmstadt, Germany
// Contact:            http://go4.gsi.de
//-----------------------------------------------------------------------
// This software can be used under the license agreements as stated
// in Go4License.txt file which is part of the distribution.
//-----------------------------------------------------------------------

#include "TGo4ObjClient.h"

#include <iostream>

#include "TROOT.h"
#include "TDirectory.h"
#include "TBuffer.h"

#include "TGo4Log.h"
#include "TGo4LockGuard.h"
#include "TGo4Socket.h"
#include "TGo4SocketSignalHandler.h"
#include "TGo4TaskHandler.h"
#include "TGo4AnalysisObjectNames.h"
#include "TGo4HistogramServer.h"

TGo4ObjClient::TGo4ObjClient() :
   TNamed(),
   fxServerName(),
   fxServerPass(),
   fxHostname(),
   fiPort(0),
   fxTransport(nullptr)
{
}

TGo4ObjClient::TGo4ObjClient(const char *name,
                                 const char *base,
                                 const char *passwd,
                                 const char *host,
                                 Int_t port) :
   TNamed(name, "This is a Go4 object client"),
   fxServerName(),
   fxServerPass(),
   fxHostname(),
   fiPort(0),
   fxTransport(nullptr)
{
   SetParms(base,passwd,host,port);
   fxTransport = new TGo4Socket(kTRUE);
}

TGo4ObjClient::~TGo4ObjClient()
{
   delete fxTransport;
}

void TGo4ObjClient::SetParms(const char *base,
               const char *passwd,
               const char *host,
               Int_t port)
{
   if(base) SetBase(base);
   if(passwd) SetPasswd(passwd);
   if(host) SetHost(host);
   if(port) SetPort(port);
}



TGo4AnalysisObjectNames *TGo4ObjClient::RequestNamesList(const char *base,
                                                         const char *passwd,
                                                         const char *host,
                                                         Int_t port)
{
   //
   TGo4AnalysisObjectNames *nameslist = nullptr;
   SetParms(base,passwd,host,port);
   if(ConnectServer() == 0)
   {
      // connection successful, go on
      SendCommand(TGo4HistogramServer::fgcCOMGETLIST); // send nameslist request
      TObject *obj=ReceiveObject(); // get incoming buffer and stream object
      if(obj && obj->InheritsFrom(TGo4AnalysisObjectNames::Class()))
      {
         nameslist=dynamic_cast<TGo4AnalysisObjectNames*>(obj);
      }
      else
      {
         TGo4Log::Error("error receiving nameslist !!!");
      }
   }
   else
   {
      TGo4Log::Error("error on connection in RequestNamesList");
      nameslist = nullptr;
   }
   DisconnectServer();
   return nameslist;
}


TObject *TGo4ObjClient::RequestObject(const char *objectname,
                                       const char *base,
                                       const char *passwd,
                                       const char *host,
                                       Int_t port)
{
   TObject *obj = nullptr;
   SetParms(base,passwd,host,port);
   if(ConnectServer() == 0)
   {
      // connection successful, go on
      SendCommand(objectname); // command is name of object to get
      obj=ReceiveObject(); // get incoming buffer and stream object
   }
   else
   {
      TGo4Log::Error("error on connection in RequestObject");
      obj = nullptr;
   }
   DisconnectServer();
   return obj;
}


TObject *TGo4ObjClient::ReceiveObject()
{
   TObject *obj = nullptr;
   // check for OK signal (object is existing on server)
   char *recvchar = fxTransport->RecvRaw("dummy");
   if(recvchar && !strcmp(recvchar,TGo4TaskHandler::Get_fgcOK()))
   {
      TBuffer *buffer=ReceiveBuffer();
      if(buffer)
      {
         // reconstruct object from buffer
         {
            TGo4LockGuard mainguard;
            // lock go4 main mutex for streaming
            TDirectory *savdir = gDirectory;
            gROOT->cd(); // be sure to be in the top directory when creating histo
            buffer->SetReadMode();
            buffer->Reset();
            obj = buffer->ReadObject(nullptr); // ReadObject(cl)
            if(obj) std::cout <<"read object of class"<<obj->ClassName() << std::endl;
            savdir->cd();
         } //  TGo4LockGuard
      }
      else
      {
         TGo4Log::Error("error receiving object");
      } // if(buffer)
   }
   else
   {
      TGo4Log::Error("Server did not send object, probably unknown!");
   } // if(!strcmp(recvchar,TGo4TaskHandler::Get_fgcOK()))
   fxTransport->Send(TGo4TaskHandler::Get_fgcOK()); // final OK
   return obj;
}

void TGo4ObjClient::SendCommand(const char *com)
{
   if (fxTransport) fxTransport->Send(com);
}


Int_t TGo4ObjClient::ConnectServer()
{
   char *recvchar = nullptr;
   Int_t openok = fxTransport->Open(GetHost(), GetPort());
   if (openok != 0)
      return 1;
   // send basename:
   fxTransport->Send(GetBase());
   recvchar = fxTransport->RecvRaw("dummy");
   if (!recvchar)
      return 1;
   if (strcmp(recvchar, TGo4TaskHandler::Get_fgcOK())) {
      TGo4Log::Debug(" Wrong basename for object server (host %s ,port %d)", GetHost(), GetPort());
      return 2;
   }
   // send password:
   fxTransport->Send(GetPasswd());
   recvchar = fxTransport->RecvRaw("dummy");
   if (!recvchar)
      return 1;
   if (strcmp(recvchar, TGo4TaskHandler::Get_fgcOK())) {
      TGo4Log::Debug(" Wrong password for object server (host %s ,port %d)", GetHost(), GetPort());
      return 4;
   }
   return 0;
}

Int_t TGo4ObjClient::DisconnectServer()
{
   fxTransport->Close();
   return 0;
}

TBuffer *TGo4ObjClient::ReceiveBuffer()
{
   TBuffer *rev = nullptr;
   Int_t state = fxTransport->ReceiveBuffer();
   if (state >= 0) {
      rev = const_cast<TBuffer *>(fxTransport->GetBuffer());
      // currently, we pass out the internal buffer of the TGo4Socket
      // maybe we have to put a queue of length 1 in between?
      // fxBufferQueue->AddBuffer(buf, kTRUE);
   }
   else {
      // error
      if (TGo4SocketSignalHandler::IsLastSignalWINCH()) {
         // TSocket error because of window resize, do not abort!
         TGo4Log::Debug(" %s: caught SIGWINCH ", GetName());
         TGo4SocketSignalHandler::SetLastSignal(0); // reset
         rev = nullptr;
      } else {
         TGo4Log::Debug(" !!!Receive Error in Object Client %s!!!", GetName());
         rev = nullptr; // here we might throw some exception later....
      }
   }
   return rev;
}