text: /*=========================================================================
  
     Program: ParaView
     Module:    pqPythonShell.cxx
  
     Copyright (c) 2005-2008 Sandia Corporation, Kitware Inc.
     All rights reserved.
  
     ParaView is a free software; you can redistribute it and/or modify it
     under the terms of the ParaView license version 1.2. 
  
     See License_v1.2.txt for the full ParaView license.
     A copy of this license can be obtained by contacting
     Kitware Inc.
     28 Corporate Drive
     Clifton Park, NY 12065
     USA
  
  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR
  CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  
  =========================================================================*/
  #include "vtkPython.h" // python first
  #include "pqPythonShell.h"
  
  #include "pqApplicationCore.h"
  #include "pqConsoleWidget.h"
  #include "pqUndoStack.h"
  #include "vtkCommand.h"
  #include "vtkProcessModule.h"
  #include "vtkPVOptions.h"
  #include "vtkPythonInteractiveInterpreter.h"
  #include "vtkPythonInterpreter.h"
  #include "vtkStdString.h"
  #include "vtkWeakPointer.h"
  
  #include <QAbstractItemView>
  #include <QInputDialog>
  #include <QStringListModel>
  #include <QTextCharFormat>
  #include <QVBoxLayout>
  
  class pqPythonShellCompleter : public pqConsoleWidgetCompleter
  {
    vtkWeakPointer<vtkPythonInteractiveInterpreter> Interpreter;
  public:
    pqPythonShellCompleter(pqPythonShell& p,
      vtkPythonInteractiveInterpreter* interp)
      {
      this->Interpreter = interp;
      this->setParent(&p);
      }
  
    virtual void updateCompletionModel(const QString& completion)
      {
      // Start by clearing the model
      this->setModel(0);
  
      // Don't try to complete the empty string
      if (completion.isEmpty())
        {
        return;
        }
  
      // Search backward through the string for usable characters
      QString textToComplete;
      for (int i = completion.length()-1; i >= 0; --i)
        {
        QChar c = completion.at(i);
        if (c.isLetterOrNumber() || c == '.' || c == '_')
          {
          textToComplete.prepend(c);
          }
        else
          {
          break;
          }
        }
  
      // Split the string at the last dot, if one exists
      QString lookup;
      QString compareText = textToComplete;
      int dot = compareText.lastIndexOf('.');
      if (dot != -1)
        {
        lookup = compareText.mid(0, dot);
        compareText = compareText.mid(dot+1);
        }
  
      // Lookup python names
      QStringList attrs;
      if (!lookup.isEmpty() || !compareText.isEmpty())
        {
        attrs = this->getPythonAttributes(lookup);
        }
  
      // Initialize the completion model
      if (!attrs.isEmpty())
        {
        this->setCompletionMode(QCompleter::PopupCompletion);
        this->setModel(new QStringListModel(attrs, this));
        this->setCaseSensitivity(Qt::CaseInsensitive);
        this->setCompletionPrefix(compareText.toLower());
        this->popup()->setCurrentIndex(this->completionModel()->index(0, 0));
        }
      }
  
    /// Given a python variable name, lookup its attributes and return them in a
    /// string list.
    QStringList getPythonAttributes(const QString& pythonObjectName)
      {
      if (this->Interpreter == NULL ||
        this->Interpreter->GetInteractiveConsoleLocalsPyObject() == NULL)
        {
        return QStringList();
        }
  
      PyObject* object = reinterpret_cast<PyObject*>(
        this->Interpreter->GetInteractiveConsoleLocalsPyObject());
      Py_INCREF(object);
  
      if (!pythonObjectName.isEmpty())
        {
        QStringList tmpNames = pythonObjectName.split('.');
        for (int i = 0; i < tmpNames.size() && object; ++i)
          {
          QByteArray tmpName = tmpNames.at(i).toLatin1();
          PyObject* prevObj = object;
          if (PyDict_Check(object))
            {
            object = PyDict_GetItemString(object, tmpName.data());
            Py_XINCREF(object);
            }
          else
            {
            object = PyObject_GetAttrString(object, tmpName.data());
            }
          Py_DECREF(prevObj);
          }
        PyErr_Clear();
        }
  
      QStringList results;
      if (object)
        {
        PyObject* keys = NULL;
        bool is_dict = PyDict_Check(object);
        if (is_dict)
          {
          keys = PyDict_Keys(object); // returns *new* reference.
          }
        else
          {
          keys = PyObject_Dir(object); // returns *new* reference.
          }
        if (keys)
          {
          PyObject* key;
          PyObject* value;
          QString keystr;
          int nKeys = PyList_Size(keys);
          for (int i = 0; i < nKeys; ++i)
            {
            key = PyList_GetItem(keys, i);
            if (is_dict)
              {
              value = PyDict_GetItem(object, key); // Return value: Borrowed reference.
              Py_XINCREF(value); // so we can use Py_DECREF later.
              }
            else
              {
              value = PyObject_GetAttr(object, key); // Return value: New refernce.
              }
            if (!value)
              {
              continue;
              }
            results << PyString_AsString(key);
            Py_DECREF(value);
            }
          Py_DECREF(keys);
          }
        Py_DECREF(object);
        }
  
      return results;
      }
  };
  
  
  //-----------------------------------------------------------------------------
  pqPythonShell::pqPythonShell(QWidget* parentObject, Qt::WindowFlags _flags):
    Superclass(parentObject, _flags),
    ConsoleWidget(new pqConsoleWidget(this)),
    Interpreter(vtkPythonInteractiveInterpreter::New()),
    Prompt(pqPythonShell::PS1()),
    Prompted(false),
    Executing(false)
  {
    QObject::connect(this, SIGNAL(executing(bool)), this, SLOT(setExecuting(bool)));
  
    this->setObjectName("pythonShell");
  
    QVBoxLayout* vbox = new QVBoxLayout(this);
    vbox->setMargin(0);
    vbox->addWidget(this->ConsoleWidget);
  
    // Setup completer for the console widget.
    pqPythonShellCompleter* completer =
      new pqPythonShellCompleter(*this, this->Interpreter);
    this->ConsoleWidget->setCompleter(completer);
  
    // Accept user input from the console and push it into the Python interpreter.
    QObject::connect(
      this->ConsoleWidget, SIGNAL(executeCommand(const QString&)),
      this, SLOT(pushScript(const QString&)));
  
    this->Interpreter->AddObserver(vtkCommand::AnyEvent,
      this, &pqPythonShell::HandleInterpreterEvents);
  }
  
  //-----------------------------------------------------------------------------
  pqPythonShell::~pqPythonShell()
  {
    this->Interpreter->RemoveObservers(vtkCommand::AnyEvent);
    this->Interpreter->Delete();
    this->Interpreter = NULL;
  
    delete this->ConsoleWidget;
    this->ConsoleWidget = NULL;
  }
  
  //-----------------------------------------------------------------------------
  void pqPythonShell::setupInterpreter()
  {
    Q_ASSERT(vtkPythonInterpreter::IsInitialized());
  
    vtkPythonInterpreter::SetCaptureStdin(true);
  
    // Print the default Python interpreter greeting.
    this->printString(
      QString("Python %1 on %2\n").arg(Py_GetVersion()).arg(Py_GetPlatform()),
      OUTPUT);
    this->prompt();
    this->printString("from paraview.simple import *\n");
    this->pushScript("from paraview.simple import *");
    this->prompt();
  }
  
  //-----------------------------------------------------------------------------
  void pqPythonShell::reset()
  {
    this->Interpreter->Reset();
    this->printString("\n...resetting...\n", ERROR);
    this->setupInterpreter();
  }
  
  //-----------------------------------------------------------------------------
  void pqPythonShell::printString(const QString& text, pqPythonShell::PrintMode mode)
  {
    QString string = text;
    if (!string.isEmpty())
      {
      QTextCharFormat format = this->ConsoleWidget->getFormat();
      switch (mode)
        {
      case OUTPUT:
        format.setForeground(QColor(0, 150, 0));
        break;
  
      case ERROR:
        format.setForeground(QColor(255, 0, 0));
        break;
  
      case STATUS:
      default:
        format.setForeground(QColor(0, 0, 150));
        }
      this->ConsoleWidget->setFormat(format);
      this->ConsoleWidget->printString(string);
      format.setForeground(QColor(0, 0, 0));
      this->ConsoleWidget->setFormat(format);
  
      this->Prompted = false;
      
      // printString by itself should never affect the Prompt, just whether it
      // needs to be shown.
      }
  }
  
  //-----------------------------------------------------------------------------
  bool pqPythonShell::prompt(const QString &indent)
  {
    if (!this->Prompted)
      {
      this->Prompted = true;
      QTextCharFormat format = this->ConsoleWidget->getFormat();
      format.setForeground(QColor(0, 0, 0));
      this->ConsoleWidget->setFormat(format);
      this->ConsoleWidget->prompt(this->Prompt);
      this->ConsoleWidget->printCommand(indent);
      return true;
      }
  
    return false;
  }
  
  //-----------------------------------------------------------------------------
  void pqPythonShell::printMessage(const QString& text)
  {
    this->printString(text, STATUS);
    this->prompt();
  }
  
  //-----------------------------------------------------------------------------
  void pqPythonShell::clear()
  {
    this->ConsoleWidget->clear();
    this->Prompted = false;
    this->prompt();
  }
  
  //-----------------------------------------------------------------------------
  void pqPythonShell::executeScript(const QString& script)
  {
    emit this->executing(true);  
    this->Interpreter->RunStringWithConsoleLocals(script.toLatin1().data());
    emit this->executing(false);
    CLEAR_UNDO_STACK();
  
    this->prompt();
  }
  
  //-----------------------------------------------------------------------------
  void pqPythonShell::pushScript(const QString& script)
  {
    QString command = script;
    command.replace("\r\n", "\n");
    command.replace("\r", "\n");
    QStringList lines = command.split("\n");
  
    this->Prompted = false;
  
    emit this->executing(true);
    foreach (QString line, lines)
      {
      bool isMultilineStatement = this->Interpreter->Push(line.toLatin1().data());
      this->Prompt = isMultilineStatement ? pqPythonShell::PS2() : pqPythonShell::PS1();
      }
    emit this->executing(false);
  
    this->prompt();
    CLEAR_UNDO_STACK();
  }
  
  //-----------------------------------------------------------------------------
  void* pqPythonShell::consoleLocals()
  {
    return this->Interpreter->GetInteractiveConsoleLocalsPyObject();
  }
  
  //-----------------------------------------------------------------------------
  void pqPythonShell::HandleInterpreterEvents(
    vtkObject*, unsigned long eventid, void* calldata)
  {
    switch (eventid)
      {
    case vtkCommand::ErrorEvent:
        {
        this->repaint();
        }
      break;
  
    case vtkCommand::SetOutputEvent:
        {
        this->repaint();
        }
      break;
  
    case vtkCommand::UpdateEvent:
        {
        vtkStdString* data = reinterpret_cast<vtkStdString*>(calldata);
        bool ok;
        QString inputText = QInputDialog::getText(this,
          tr("Enter Input requested by Python"),
          tr("Input: "),
          QLineEdit::Normal,
          QString(),
          &ok);
        if (ok)
          {
          *data = inputText.toStdString();
          }
        }
      break;
      }
  }
  