// Created on: 1995-02-23
// Created by: Remi LEQUETTE
// Copyright (c) 1995-1999 Matra Datavision
// Copyright (c) 1999-2014 OPEN CASCADE SAS
//
// This file is part of Open CASCADE Technology software library.
//
// This library is free software; you can redistribute it and/or modify it under
// the terms of the GNU Lesser General Public License version 2.1 as published
// by the Free Software Foundation, with special exception defined in the file
// OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
// distribution for complete text of the license and disclaimer of any warranty.
//
// Alternatively, this file may be used under the terms of Open CASCADE
// commercial license or contractual agreement.

#include <Draw_Interpretor.hxx>

#include <Draw_Appli.hxx>
#include <Message.hxx>
#include <Message_PrinterOStream.hxx>
#include <OSD.hxx>
#include <OSD_Path.hxx>
#include <Standard_SStream.hxx>
#include <Standard_ErrorHandler.hxx>
#include <Standard_Macro.hxx>
#include <TCollection_AsciiString.hxx>
#include <TCollection_ExtendedString.hxx>

#include <cstring>
#include <tcl.h>
#include <fcntl.h>
#ifndef _WIN32
  #include <unistd.h>
#endif

// for capturing of cout and cerr (dup(), dup2())
#ifdef _WIN32
  #include <io.h>
  #include <sys/stat.h>
#endif

#if !defined(STDOUT_FILENO)
  #define STDOUT_FILENO fileno(stdout)
#endif
#if !defined(STDERR_FILENO)
  #define STDERR_FILENO fileno(stderr)
#endif

#if ((TCL_MAJOR_VERSION > 8) || ((TCL_MAJOR_VERSION == 8) && (TCL_MINOR_VERSION >= 1)))
  #define TCL_USES_UTF8
#endif

// logging helpers
namespace
{
void dumpArgs(Standard_OStream& os, int argc, const char* argv[])
{
  for (int i = 0; i < argc; i++)
  {
    os << argv[i] << " ";
  }
  os << '\n';
}

void flush_standard_streams()
{
  fflush(stderr);
  fflush(stdout);
  std::cerr << std::flush;
  std::cout << std::flush;
}

int capture_start(int theFDStd, int theFDLog)
{
  Standard_ASSERT_RETURN(theFDLog >= 0, "Invalid descriptor of log file", -1);

  // Duplicate a file descriptor of the standard stream to be able to restore output to it later
  int aFDSave = dup(theFDStd);
  if (aFDSave < 0)
  {
    perror("Error capturing standard stream to log: dup() returned");
    return -1;
  }

  // Redirect the stream to the log file
  if (dup2(theFDLog, theFDStd) < 0)
  {
    close(aFDSave);
    perror("Error capturing standard stream to log: dup2() returned");
    return -1;
  }

  // remember saved file descriptor of standard stream
  return aFDSave;
}

void capture_end(int theFDStd, int& theFDSave)
{
  if (theFDSave < 0)
  {
    return;
  }

  // restore normal descriptors of console stream
  if (dup2(theFDSave, theFDStd) < 0)
  {
    perror("Error returning capturing standard stream to log: dup2() returned");
    return;
  }

  // close saved file descriptor
  close(theFDSave);
  theFDSave = -1;
}

} // anonymous namespace

static int CommandCmd(ClientData theClientData, Tcl_Interp* interp, int argc, const char* argv[])
{
  int                             code      = TCL_OK;
  Draw_Interpretor::CallBackData* aCallback = (Draw_Interpretor::CallBackData*)theClientData;
  Draw_Interpretor&               di        = *(aCallback->myDI);

  // log command execution, except commands manipulating log itself and echo
  bool isLogManipulation = (strcmp(argv[0], "dlog") == 0 || strcmp(argv[0], "decho") == 0);
  bool doLog             = (di.GetDoLog() && !isLogManipulation);
  bool doEcho            = (di.GetDoEcho() && !isLogManipulation);

  // flush cerr and cout
  flush_standard_streams();

  // capture cout and cerr to log
  int aFDstdout   = STDOUT_FILENO;
  int aFDstderr   = STDERR_FILENO;
  int aFDerr_save = -1;
  int aFDout_save = -1;
  if (doLog)
  {
    aFDout_save = capture_start(aFDstdout, di.GetLogFileDescriptor());
    aFDerr_save = capture_start(aFDstderr, di.GetLogFileDescriptor());
  }

  if (doEcho || doLog)
  {
    dumpArgs(std::cout, argc, argv);
  }

  // run command
  try
  {
    OCC_CATCH_SIGNALS

    // get exception if control-break has been pressed
    OSD::ControlBreak();

    int fres = aCallback->Invoke(di, argc, argv /*anArgs.GetArgv()*/);
    if (fres != 0)
    {
      code = TCL_ERROR;
    }
  }
  catch (Standard_Failure const& anException)
  {
    // fail if Draw_ExitOnCatch is set
    const char* toExitOnCatch = Tcl_GetVar(interp, "Draw_ExitOnCatch", TCL_GLOBAL_ONLY);
    if (toExitOnCatch != nullptr && Draw::Atoi(toExitOnCatch))
    {
      Message::SendFail() << "An exception was caught " << anException;
#ifdef _WIN32
      Tcl_Exit(0);
#else
      Tcl_Eval(interp, "exit");
#endif
    }

    Standard_SStream ss;
    ss << "An exception was caught " << anException << std::ends;
    Tcl_SetResult(interp, (char*)(ss.str().c_str()), TCL_VOLATILE);
    code = TCL_ERROR;
  }
  catch (std::exception const& theStdException)
  {
    const char* toExitOnCatch = Tcl_GetVar(interp, "Draw_ExitOnCatch", TCL_GLOBAL_ONLY);
    if (toExitOnCatch != nullptr && Draw::Atoi(toExitOnCatch))
    {
      Message::SendFail() << "An exception was caught " << theStdException.what() << " ["
                          << typeid(theStdException).name() << "]";
#ifdef _WIN32
      Tcl_Exit(0);
#else
      Tcl_Eval(interp, "exit");
#endif
    }

    Standard_SStream ss;
    ss << "An exception was caught " << theStdException.what() << " ["
       << typeid(theStdException).name() << "]" << std::ends;
    Tcl_SetResult(interp, (char*)(ss.str().c_str()), TCL_VOLATILE);
    code = TCL_ERROR;
  }
  catch (...)
  {
    const char* toExitOnCatch = Tcl_GetVar(interp, "Draw_ExitOnCatch", TCL_GLOBAL_ONLY);
    if (toExitOnCatch != nullptr && Draw::Atoi(toExitOnCatch))
    {
      Message::SendFail() << "UNKNOWN exception was caught ";
#ifdef _WIN32
      Tcl_Exit(0);
#else
      Tcl_Eval(interp, "exit");
#endif
    }

    Standard_SStream ss;
    ss << "UNKNOWN exception was caught " << std::ends;
    Tcl_SetResult(interp, (char*)(ss.str().c_str()), TCL_VOLATILE);
    code = TCL_ERROR;
  }

  // log command result
  if (doLog || doEcho)
  {
    const char* aResultStr = Tcl_GetStringResult(interp);
    if (aResultStr != nullptr && aResultStr[0] != '\0')
    {
      std::cout << aResultStr << '\n';
    }
  }

  // flush streams
  flush_standard_streams();

  // end capturing cout and cerr
  if (doLog)
  {
    capture_end(aFDstderr, aFDerr_save);
    capture_end(aFDstdout, aFDout_save);
  }

  return code;
}

static void CommandDelete(ClientData theClientData)
{
  Draw_Interpretor::CallBackData* aCallback = (Draw_Interpretor::CallBackData*)theClientData;
  delete aCallback;
}

//=================================================================================================

Draw_Interpretor::Draw_Interpretor()
    : // the tcl interpreter is not created immediately as it is kept
      // by a global variable and created and deleted before the main()
      myInterp(nullptr),
      isAllocated(false),
      myDoLog(false),
      myDoEcho(false),
      myToColorize(true),
      myFDLog(-1)
{
}

//=================================================================================================

Draw_Interpretor::Draw_Interpretor(const Draw_PInterp& theInterp)
    : myInterp(theInterp),
      isAllocated(false),
      myDoLog(false),
      myDoEcho(false),
      myToColorize(true),
      myFDLog(-1)
{
}

//=======================================================================
// function : Init
// purpose  : It is necessary to call this function
//=======================================================================

void Draw_Interpretor::Init()
{
  if (isAllocated)
  {
    Tcl_DeleteInterp(myInterp);
  }
  isAllocated = true;
  myInterp    = Tcl_CreateInterp();
}

//=================================================================================================

void Draw_Interpretor::SetToColorize(bool theToColorize)
{
  myToColorize = theToColorize;
  for (NCollection_Sequence<occ::handle<Message_Printer>>::Iterator aPrinterIter(
         Message::DefaultMessenger()->Printers());
       aPrinterIter.More();
       aPrinterIter.Next())
  {
    if (occ::handle<Message_PrinterOStream> aPrinter =
          occ::down_cast<Message_PrinterOStream>(aPrinterIter.Value()))
    {
      aPrinter->SetToColorize(theToColorize);
    }
  }
}

//=================================================================================================

void Draw_Interpretor::add(const char* const               theCommandName,
                           const char* const               theHelp,
                           const char* const               theFileName,
                           Draw_Interpretor::CallBackData* theCallback,
                           const char* const               theGroup)
{
  Standard_ASSERT_RAISE(myInterp != nullptr, "Attempt to add command to Null interpreter");

  Tcl_CreateCommand(myInterp, theCommandName, CommandCmd, (ClientData)theCallback, CommandDelete);

  // add the help
  Tcl_SetVar2(myInterp, "Draw_Helps", theCommandName, theHelp, TCL_GLOBAL_ONLY);
  Tcl_SetVar2(myInterp,
              "Draw_Groups",
              theGroup,
              theCommandName,
              TCL_GLOBAL_ONLY | TCL_APPEND_VALUE | TCL_LIST_ELEMENT);

  // add path to source file (keep not more than two last subdirectories)
  if (theFileName == nullptr || *theFileName == '\0')
  {
    return;
  }

  OSD_Path aPath(theFileName);
  int      nbTrek = aPath.TrekLength();
  for (int i = 4; i < nbTrek; ++i)
  {
    aPath.RemoveATrek(1);
  }
  aPath.SetDisk("");
  aPath.SetNode("");
  TCollection_AsciiString aSrcPath;
  aPath.SystemName(aSrcPath);
  if (aSrcPath.Value(1) == '/')
  {
    aSrcPath.Remove(1);
  }
  Tcl_SetVar2(myInterp, "Draw_Files", theCommandName, aSrcPath.ToCString(), TCL_GLOBAL_ONLY);
}

//=================================================================================================

bool Draw_Interpretor::Remove(const char* const n)
{
  Standard_PCharacter pN;
  //
  pN = (Standard_PCharacter)n;

  int result = Tcl_DeleteCommand(myInterp, pN);
  return result == 0;
}

//=================================================================================================

const char* Draw_Interpretor::Result() const
{
#if ((TCL_MAJOR_VERSION > 8) || ((TCL_MAJOR_VERSION == 8) && (TCL_MINOR_VERSION >= 5)))
  return Tcl_GetStringResult(myInterp);
#else
  return myInterp->result;
#endif
}

//=================================================================================================

void Draw_Interpretor::Reset()
{
  Tcl_ResetResult(myInterp);
}

//=================================================================================================

Draw_Interpretor& Draw_Interpretor::Append(const char* const s)
{
  Tcl_AppendResult(myInterp, s, (const char*)nullptr);
  return *this;
}

//=================================================================================================

Draw_Interpretor& Draw_Interpretor::Append(const TCollection_AsciiString& s)
{
  return Append(s.ToCString());
}

//=================================================================================================

Draw_Interpretor& Draw_Interpretor::Append(const TCollection_ExtendedString& theString)
{
#ifdef TCL_USES_UTF8
  // Convert string to UTF-8 format for Tcl
  char* str = new char[theString.LengthOfCString() + 1];
  theString.ToUTF8CString(str);
  Tcl_AppendResult(myInterp, str, (const char*)nullptr);
  delete[] str;
#else
  // put as ascii string, replacing non-ascii characters by '?'
  TCollection_AsciiString str(theString, '?');
  Tcl_AppendResult(myInterp, str.ToCString(), (const char*)0);
#endif
  return *this;
}

//=================================================================================================

Draw_Interpretor& Draw_Interpretor::Append(const int i)
{
  char c[100];
  Sprintf(c, "%d", i);
  Tcl_AppendResult(myInterp, c, (const char*)nullptr);
  return *this;
}

//=================================================================================================

Draw_Interpretor& Draw_Interpretor::Append(const size_t theResult)
{
  char c[100];
  Sprintf(c, "%zu", theResult);
  Tcl_AppendResult(myInterp, c, (const char*)nullptr);
  return *this;
}

//=================================================================================================

Draw_Interpretor& Draw_Interpretor::Append(const double r)
{
  char s[100];
  Sprintf(s, "%.17g", r);
  Tcl_AppendResult(myInterp, s, (const char*)nullptr);
  return *this;
}

//=================================================================================================

Draw_Interpretor& Draw_Interpretor::Append(const Standard_SStream& s)
{
  return Append(s.str().c_str());
}

//=================================================================================================

void Draw_Interpretor::AppendElement(const char* const s)
{
  Tcl_AppendElement(myInterp, s);
}

//=================================================================================================

int Draw_Interpretor::Eval(const char* const line)
{
  return Tcl_Eval(myInterp, line);
}

//=================================================================================================

int Draw_Interpretor::RecordAndEval(const char* const line, const int flags)
{
  return Tcl_RecordAndEval(myInterp, line, flags);
}

//=================================================================================================

int Draw_Interpretor::EvalFile(const char* const fname)
{
  return Tcl_EvalFile(myInterp, fname);
}

//=================================================================================================

int Draw_Interpretor::PrintHelp(const char* const theCommandName)
{
  TCollection_AsciiString aCmd     = TCollection_AsciiString("help ") + theCommandName;
  Standard_PCharacter     aLinePtr = (Standard_PCharacter)aCmd.ToCString();
  return Tcl_Eval(myInterp, aLinePtr);
}

//=================================================================================================

bool Draw_Interpretor::Complete(const char* const line)
{
  Standard_PCharacter pLine;
  //
  pLine = (Standard_PCharacter)line;
  return Tcl_CommandComplete(pLine) != 0;
}

//=================================================================================================

Draw_Interpretor::~Draw_Interpretor()
{
  SetDoLog(false);
  if (myFDLog >= 0)
  {
    close(myFDLog);
    myFDLog = 0;
  }

  // MKV 01.02.05
#if ((TCL_MAJOR_VERSION > 8) || ((TCL_MAJOR_VERSION == 8) && (TCL_MINOR_VERSION >= 4)))
  try
  {
    OCC_CATCH_SIGNALS
    Tcl_Exit(0);
  }
  catch (Standard_Failure const&)
  {
  #ifdef OCCT_DEBUG
    std::cout << "Tcl_Exit have an exception" << std::endl;
  #endif
  }
#else
  #ifdef _WIN32
  Tcl_Exit(0);
  #endif
#endif
}

//=================================================================================================

Draw_PInterp Draw_Interpretor::Interp() const
{
  Standard_DomainError_Raise_if(myInterp == nullptr, "No call for  Draw_Interpretor::Init()");
  return myInterp;
}

void Draw_Interpretor::Set(const Draw_PInterp& PIntrp)
{
  if (isAllocated)
  {
    Tcl_DeleteInterp(myInterp);
  }
  isAllocated = false;
  myInterp    = PIntrp;
}

//=================================================================================================

void Draw_Interpretor::SetDoLog(bool doLog)
{
  if (myDoLog == doLog)
  {
    return;
  }

  // create log file if not opened yet
  if (doLog && myFDLog < 0)
  {
#ifdef _WIN32
    char tmpfile[L_tmpnam + 1];
    tmpnam(tmpfile);
    myFDLog = open(tmpfile, O_RDWR | O_CREAT | O_EXCL | O_TEMPORARY, S_IREAD | S_IWRITE);
#else
    // according to Linux Filesystem Hierarchy Standard, 3.17,
    // /tmp/ is the right directory for temporary files
    char tmpfile[256] = "/tmp/occt_draw_XXXXXX";
    myFDLog           = mkstemp(tmpfile);
    if (myFDLog >= 0)
    {
      //      printf ("Tmp file: %s\n", tmpfile);
      unlink(tmpfile); // make sure the file will be deleted on close
    }
#endif
    if (myFDLog < 0)
    {
      perror("Error creating temporary file for capturing console output");
      printf("path: %s\n", tmpfile);
      return;
    }
  }

  myDoLog = doLog;
}

void Draw_Interpretor::SetDoEcho(bool doEcho)
{
  myDoEcho = doEcho;
}

bool Draw_Interpretor::GetDoLog() const
{
  return myDoLog;
}

bool Draw_Interpretor::GetDoEcho() const
{
  return myDoEcho;
}

void Draw_Interpretor::ResetLog()
{
  if (myFDLog < 0)
  {
    return;
  }

  // flush cerr and cout, for the case if they are bound to the log
  flush_standard_streams();

  lseek(myFDLog, 0, SEEK_SET);

#ifdef _WIN32
  if (_chsize_s(myFDLog, 0) != 0)
#else
  if (ftruncate(myFDLog, 0) != 0)
#endif
  {
    perror("Error truncating the console log");
  }
}

void Draw_Interpretor::AddLog(const char* const theStr)
{
  if (myFDLog < 0 || !theStr || !theStr[0])
  {
    return;
  }

  // flush cerr and cout, for the case if they are bound to the log
  flush_standard_streams();

  // write as plain bytes
  if (write(myFDLog, theStr, (unsigned int)strlen(theStr)) < 0)
  {
    perror("Error writing to console log");
  }
}

TCollection_AsciiString Draw_Interpretor::GetLog()
{
  TCollection_AsciiString aLog;
  if (myFDLog < 0)
  {
    return aLog;
  }

  // flush cerr and cout
  flush_standard_streams();

  // rewind the file to its start
  lseek(myFDLog, 0, SEEK_SET);

  // read the whole log to string; this implementation
  // is not optimized but should be sufficient
  const int BUFSIZE = 4096;
  char      buffer[BUFSIZE + 1];
  for (;;)
  {
    int nbRead = (int)read(myFDLog, buffer, BUFSIZE);
    if (nbRead <= 0)
    {
      break;
    }
    buffer[nbRead] = '\0';
    aLog.AssignCat(buffer);
  }

  return aLog;
}
