/*=========================================================================

  Program:   Visualization Toolkit
  Module:    vtkPythonProgrammableFilter.cxx

  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
  All rights reserved.
  See Copyright.txt or http://www.kitware.com/Copyright.htm for details.

     This software is distributed WITHOUT ANY WARRANTY; without even
     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
     PURPOSE.  See the above copyright notice for more information.

=========================================================================*/
#include "vtkPythonProgrammableFilter.h"

#include "vtkCommand.h"
#include "vtkDataObject.h"
#include "vtkDataObjectTypes.h"
#include "vtkDataSet.h"
#include "vtkInformation.h"
#include "vtkInformationVector.h"
#include "vtkObjectFactory.h"
#include "vtkPVOptions.h"
#include "vtkProcessModule.h"
#include "vtkPythonInterpreter.h"
#include "vtkStreamingDemandDrivenPipeline.h"

#include <algorithm>
#include <map>
#include <sstream>
#include <string>
#include <vtksys/SystemTools.hxx>

vtkStandardNewMacro(vtkPythonProgrammableFilter);

//----------------------------------------------------------------------------

typedef std::map<std::string, std::string> ParametersT;
typedef std::map<std::string, std::vector<std::string> > RepeatableParametersT;

class vtkPythonProgrammableFilterImplementation
{
public:
  // Stores name-value parameters that will be passed to running scripts
  ParametersT Parameters;

  RepeatableParametersT RepeatableParameters;
};

//----------------------------------------------------------------------------
vtkPythonProgrammableFilter::vtkPythonProgrammableFilter()
  : Implementation(new vtkPythonProgrammableFilterImplementation())
{
  this->Script = nullptr;
  this->InformationScript = nullptr;
  this->UpdateExtentScript = nullptr;
  this->CheckNeedsUpdateScript = nullptr;
  this->PythonPath = nullptr;
  this->SetExecuteMethod(vtkPythonProgrammableFilter::ExecuteScript, this);
  this->OutputDataSetType = VTK_POLY_DATA;
  this->NeedsUpdate = false;
  this->Request = nullptr;
}

//----------------------------------------------------------------------------
vtkPythonProgrammableFilter::~vtkPythonProgrammableFilter()
{
  this->SetScript(nullptr);
  this->SetInformationScript(nullptr);
  this->SetUpdateExtentScript(nullptr);
  this->SetPythonPath(nullptr);

  delete this->Implementation;
}

//----------------------------------------------------------------------------
int vtkPythonProgrammableFilter::RequestDataObject(vtkInformation* vtkNotUsed(request),
  vtkInformationVector** inputVector, vtkInformationVector* outputVector)
{
  if (this->OutputDataSetType == VTK_DATA_SET)
  {
    // Output type is same as input
    vtkInformation* inInfo = inputVector[0]->GetInformationObject(0);
    if (!inInfo)
    {
      return 0;
    }
    vtkDataObject* input = inInfo->Get(vtkDataObject::DATA_OBJECT());
    if (input)
    {
      // for each output
      for (int i = 0; i < this->GetNumberOfOutputPorts(); ++i)
      {
        vtkInformation* info = outputVector->GetInformationObject(i);
        vtkDataObject* output = info->Get(vtkDataObject::DATA_OBJECT());

        if (!output || !output->IsA(input->GetClassName()))
        {
          vtkDataObject* newOutput = input->NewInstance();
          info->Set(vtkDataObject::DATA_OBJECT(), newOutput);
          newOutput->Delete();
          this->GetOutputPortInformation(0)->Set(
            vtkDataObject::DATA_EXTENT_TYPE(), newOutput->GetExtentType());
        }
      }
      return 1;
    }
    return 0;
  }

  const char* outTypeStr = vtkDataObjectTypes::GetClassNameFromTypeId(this->OutputDataSetType);

  // for each output
  for (int i = 0; i < this->GetNumberOfOutputPorts(); ++i)
  {
    vtkInformation* info = outputVector->GetInformationObject(i);
    vtkDataObject* output = info->Get(vtkDataObject::DATA_OBJECT());
    if (!output || !output->IsA(outTypeStr))
    {
      vtkDataObject* newOutput = vtkDataObjectTypes::NewDataObject(this->OutputDataSetType);
      if (!newOutput)
      {
        vtkErrorMacro("Could not create chosen output data type: " << outTypeStr);
        return 0;
      }
      info->Set(vtkDataObject::DATA_OBJECT(), newOutput);
      this->GetOutputPortInformation(0)->Set(
        vtkDataObject::DATA_EXTENT_TYPE(), newOutput->GetExtentType());
      newOutput->Delete();
    }
  }

  return 1;
}

//----------------------------------------------------------------------------
int vtkPythonProgrammableFilter::RequestInformation(
  vtkInformation*, vtkInformationVector**, vtkInformationVector*)
{
  if (this->InformationScript)
  {
    this->Exec(this->InformationScript, "RequestInformation");
  }
  return 1;
}

//----------------------------------------------------------------------------
int vtkPythonProgrammableFilter::RequestUpdateExtent(
  vtkInformation* request, vtkInformationVector** inputVector, vtkInformationVector* outputVector)
{
  if (this->UpdateExtentScript)
  {
    this->Exec(this->UpdateExtentScript, "RequestUpdateExtent");
    return 1;
  }

  return this->Superclass::RequestUpdateExtent(request, inputVector, outputVector);
}

//----------------------------------------------------------------------------
int vtkPythonProgrammableFilter::ProcessRequest(
  vtkInformation* request, vtkInformationVector** inputVector, vtkInformationVector* outputVector)
{
  this->Request = request;
  int retVal = this->Superclass::ProcessRequest(request, inputVector, outputVector);
  this->Request = nullptr;
  return retVal;
}
//----------------------------------------------------------------------------
void vtkPythonProgrammableFilter::SetParameterInternal(const char* raw_name, const char* raw_value)
{
  const std::string name = raw_name ? raw_name : "";
  const std::string value = raw_value ? raw_value : "";

  if (name.empty())
  {
    vtkErrorMacro(<< "cannot set parameter with empty name");
    return;
  }

  this->Implementation->Parameters[name] = value;
  this->Modified();
}

//----------------------------------------------------------------------------
void vtkPythonProgrammableFilter::SetParameter(const char* raw_name, int value)
{
  std::ostringstream buf;
  buf << value;
  this->SetParameterInternal(raw_name, buf.str().c_str());
}

//----------------------------------------------------------------------------
void vtkPythonProgrammableFilter::SetParameter(const char* raw_name, double value)
{
  std::ostringstream buf;
  buf << value;
  this->SetParameterInternal(raw_name, buf.str().c_str());
}

//----------------------------------------------------------------------------
void vtkPythonProgrammableFilter::SetParameter(const char* raw_name, const char* value)
{
  std::ostringstream buf;
  buf << "r'" << value << "'";
  this->SetParameterInternal(raw_name, buf.str().c_str());
}

//----------------------------------------------------------------------------
void vtkPythonProgrammableFilter::SetParameter(
  const char* raw_name, double value1, double value2, double value3)
{
  std::ostringstream buf;
  buf << "[" << value1 << ", " << value2 << ", " << value3 << "]";
  this->SetParameterInternal(raw_name, buf.str().c_str());
}

//----------------------------------------------------------------------------
void vtkPythonProgrammableFilter::SetParameter(const char* raw_name, double value1, double value2)
{
  std::ostringstream buf;
  buf << "[" << value1 << ", " << value2 << "]";
  this->SetParameterInternal(raw_name, buf.str().c_str());
}

//----------------------------------------------------------------------------
void vtkPythonProgrammableFilter::ClearParameters()
{
  this->Implementation->Parameters.clear();
  this->Implementation->RepeatableParameters.clear();
  this->Modified();
}

//----------------------------------------------------------------------------
void vtkPythonProgrammableFilter::AddParameter(const char* name, const char* value)
{
  if (!name || !name[0])
  {
    vtkErrorMacro(<< "cannot set parameter with empty name");
    return;
  }
  std::ostringstream buf;
  buf << "r'" << (value ? value : "") << "'";
  this->Implementation->RepeatableParameters[name].push_back(buf.str());
  this->Modified();
}

//----------------------------------------------------------------------------
void vtkPythonProgrammableFilter::ClearParameter(const char* name)
{
  if (!name || !name[0])
  {
    vtkErrorMacro(<< "cannot clear parameter with empty name");
    return;
  }
  RepeatableParametersT::iterator iter = this->Implementation->RepeatableParameters.find(name);
  if (iter != this->Implementation->RepeatableParameters.end())
  {
    this->Implementation->RepeatableParameters.erase(iter);
    this->Modified();
  }
}

//----------------------------------------------------------------------------
void vtkPythonProgrammableFilter::ExecuteScript(void* arg)
{
  vtkPythonProgrammableFilter* self = static_cast<vtkPythonProgrammableFilter*>(arg);
  if (self)
  {
    self->NeedsUpdate = false;
    self->Exec(self->GetScript(), "RequestData");
  }
}

//----------------------------------------------------------------------------
void vtkPythonProgrammableFilter::Exec(const char* script, const char* funcname)
{
  if (!script || !strlen(script))
  {
    return;
  }

  // initialize Python is not already.
  vtkPythonInterpreter::Initialize();

  // Prepend the paths defined in PythonPath to sys.path
  if (this->PythonPath)
  {
    std::string pathscript;
    pathscript += "import sys\n";
    std::vector<std::string> paths = vtksys::SystemTools::SplitString(this->PythonPath, ';');
    for (unsigned int cc = 0; cc < static_cast<unsigned int>(paths.size()); cc++)
    {
      if (!paths[cc].empty())
      {
        std::string path = paths[cc];

        // Remove any quotes from the path
        path.erase(std::remove(path.begin(), path.end(), '"'), path.end());
        path.erase(std::remove(path.begin(), path.end(), '\''), path.end());

        // Re-add qoutes
        path = std::string("\"").append(path).append("\"");

        pathscript += std::string("if not ").append(path).append(" in sys.path:\n");
        pathscript += std::string("  sys.path.insert(0, ").append(path).append(")\n");

        vtkPythonInterpreter::RunSimpleString(pathscript.c_str());
      }
    }
  }

  // Remove the function if it already exists
  std::string cleanupScript = "try: del " + std::string(funcname) + "\n"
                                                                    "except NameError: pass\n";
  vtkPythonInterpreter::RunSimpleString(cleanupScript.c_str());

  // Construct a script that defines a function
  std::string fscript;
  fscript = "def ";
  fscript += funcname;

  // Set the parameters defined by user.
  fscript += "(self, inputs = None, output = None, request = None):\n";
  for (ParametersT::const_iterator parameter = this->Implementation->Parameters.begin();
       parameter != this->Implementation->Parameters.end(); ++parameter)
  {
    fscript += "  " + parameter->first + " = " + parameter->second + "\n";
  }

  for (RepeatableParametersT::const_iterator rparameter =
         this->Implementation->RepeatableParameters.begin();
       rparameter != this->Implementation->RepeatableParameters.end(); ++rparameter)
  {
    fscript += "  " + rparameter->first + " = [\\\n";

    for (std::vector<std::string>::const_iterator parameter = rparameter->second.begin();
         parameter != rparameter->second.end(); ++parameter)
    {
      fscript += "    " + (*parameter) + ",\n";
    }
    fscript += "]\n";
  }

  // Indent user script
  fscript += "  ";

  // Replace tabs with two spaces
  std::string orgscript;
  size_t len = strlen(script);
  for (size_t i = 0; i < len; i++)
  {
    if (script[i] == '\t')
    {
      orgscript += "  ";
    }
    else
    {
      orgscript.push_back(script[i]);
    }
  }
  // Remove DOS line endings. They confuse the indentation code below.
  orgscript.erase(std::remove(orgscript.begin(), orgscript.end(), '\r'), orgscript.end());

  std::string::iterator it = orgscript.begin();
  for (; it != orgscript.end(); it++)
  {
    fscript += *it;
    // indent new lines
    if (*it == '\n')
    {
      fscript += "  ";
    }
  }
  fscript += "\n";
  vtkPythonInterpreter::RunSimpleString(fscript.c_str());

  std::string runscript;

  runscript += "from paraview import vtk\n";
  runscript +=
    "from paraview.modules.vtkPVVTKExtensionsFiltersPython import vtkPythonProgrammableFilter\n";
  runscript += "hasnumpy = True\n";
  runscript += "try:\n";
  runscript += "  from numpy import *\n";
  runscript += "except ImportError:\n";
  runscript += "  hasnumpy = False\n";
  runscript += "if hasnumpy:\n";
  runscript += "  from paraview.vtk.numpy_interface import dataset_adapter\n";
  runscript += "  from paraview.vtk.numpy_interface.algorithms import *\n";

  // Set self to point to this
  char addrofthis[1024];
  sprintf(addrofthis, "%p", this);
  char* aplusthis = addrofthis;
  if ((addrofthis[0] == '0') && ((addrofthis[1] == 'x') || addrofthis[1] == 'X'))
  {
    aplusthis += 2; // skip over "0x"
  }

  // Call the function
  runscript += "myarg = ";
  runscript += "vtkPythonProgrammableFilter('";
  runscript += aplusthis;
  runscript += "')\n";

  // pass in the request, but do some error checking first.
  runscript += "request = ";
  if (this->Request)
  {
    // Set pointer to request
    char addrofrequest[1024];
    sprintf(addrofrequest, "%p", this->Request);
    char* aplusrequest = addrofrequest;
    if ((addrofrequest[0] == '0') && ((addrofrequest[1] == 'x') || addrofrequest[1] == 'X'))
    {
      aplusrequest += 2; // skip over "0x"
    }
    runscript += "vtk.vtkInformation('";
    runscript += aplusrequest;
    runscript += "')\n";
  }
  else
  {
    vtkWarningMacro("Request is not set.");
    runscript += "None\n";
  }
  runscript += "if hasnumpy:\n";
  runscript += "  inputs = []\n";
  runscript += "  index = 0\n";
  int numinps = this->GetNumberOfInputConnections(0);
  for (int i = 0; i < numinps; i++)
  {
    runscript +=
      "  inputs.append(dataset_adapter.WrapDataObject(myarg.GetInputDataObject(0, index)))\n";
    runscript += "  index += 1\n";
  }
  runscript += "  output = dataset_adapter.WrapDataObject(myarg.GetOutputDataObject(0))\n";
  runscript += "else:\n";
  runscript += "  inputs = None\n";
  runscript += "  output = None\n";

  // Call the function
  runscript += funcname;
  runscript += "(myarg, inputs, output, request)\n";
  runscript += "del inputs\n";
  runscript += "del output\n";
  runscript += "del myarg\n";
  runscript += "del request\n";
  runscript += "import gc\n";
  runscript += "gc.collect()\n";

  vtkPythonInterpreter::RunSimpleString(runscript.c_str());
}

//----------------------------------------------------------------------------
int vtkPythonProgrammableFilter::FillOutputPortInformation(
  int vtkNotUsed(port), vtkInformation* info)
{
  // now add our info
  info->Set(vtkDataObject::DATA_TYPE_NAME(), "vtkDataObject");
  return 1;
}

//----------------------------------------------------------------------------
int vtkPythonProgrammableFilter::FillInputPortInformation(int port, vtkInformation* info)
{
  if (!this->Superclass::FillInputPortInformation(port, info))
  {
    return 0;
  }
  if (port == 0)
  {
    info->Set(vtkAlgorithm::INPUT_REQUIRED_DATA_TYPE(), "vtkDataObject");
    info->Set(vtkAlgorithm::INPUT_IS_REPEATABLE(), 1);
    info->Set(vtkAlgorithm::INPUT_IS_OPTIONAL(), 1);
  }
  return 1;
}

//----------------------------------------------------------------------------
bool vtkPythonProgrammableFilter::GetNeedsUpdate()
{
  if (this->CheckNeedsUpdateScript && this->CheckNeedsUpdateScript[0] != '\0')
  {
    this->Exec(this->CheckNeedsUpdateScript, "CheckNeedsUpdate");
  }
  return this->NeedsUpdate;
}

//----------------------------------------------------------------------------
void vtkPythonProgrammableFilter::PrintSelf(ostream& os, vtkIndent indent)
{
  this->Superclass::PrintSelf(os, indent);
  os << indent << "OutputDataSetType: " << this->OutputDataSetType << endl;
  os << indent << "PythonPath: " << (this->PythonPath ? this->PythonPath : "(none)") << endl;
  if (this->Request)
  {
    os << indent << "Request: " << this->Request << endl;
  }
  else
  {
    os << indent << "Request: (None)" << endl;
  }
  os << indent << "NeedsUpdate: " << this->NeedsUpdate << endl;
}
