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

  Program:   Visualization Toolkit
  Module:    vtkLineWidget2.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 "vtkLineWidget2.h"
#include "vtkLineRepresentation.h"
#include "vtkPointHandleRepresentation3D.h"
#include "vtkHandleWidget.h"
#include "vtkCommand.h"
#include "vtkCallbackCommand.h"
#include "vtkRenderWindowInteractor.h"
#include "vtkObjectFactory.h"
#include "vtkWidgetEventTranslator.h"
#include "vtkWidgetCallbackMapper.h"
#include "vtkEvent.h"
#include "vtkWidgetEvent.h"
#include "vtkRenderWindow.h"


vtkStandardNewMacro(vtkLineWidget2);

//----------------------------------------------------------------------------
vtkLineWidget2::vtkLineWidget2()
{
  this->WidgetState = vtkLineWidget2::Start;
  this->ManagesCursor = 1;
  this->CurrentHandle = 0;

  // The widgets for moving the end points. They observe this widget (i.e.,
  // this widget is the parent to the handles).
  this->Point1Widget = vtkHandleWidget::New();
  this->Point1Widget->SetPriority(this->Priority-0.01);
  this->Point1Widget->SetParent(this);
  this->Point1Widget->ManagesCursorOff();

  this->Point2Widget = vtkHandleWidget::New();
  this->Point2Widget->SetPriority(this->Priority-0.01);
  this->Point2Widget->SetParent(this);
  this->Point2Widget->ManagesCursorOff();

  this->LineHandle = vtkHandleWidget::New();
  this->LineHandle->SetPriority(this->Priority-0.01);
  this->LineHandle->SetParent(this);
  this->LineHandle->ManagesCursorOff();

  // Define widget events
  this->CallbackMapper->SetCallbackMethod(vtkCommand::LeftButtonPressEvent,
                                          vtkWidgetEvent::Select,
                                          this, vtkLineWidget2::SelectAction);
  this->CallbackMapper->SetCallbackMethod(vtkCommand::LeftButtonReleaseEvent,
                                          vtkWidgetEvent::EndSelect,
                                          this, vtkLineWidget2::EndSelectAction);
  this->CallbackMapper->SetCallbackMethod(vtkCommand::MiddleButtonPressEvent,
                                          vtkWidgetEvent::Translate,
                                          this, vtkLineWidget2::TranslateAction);
  this->CallbackMapper->SetCallbackMethod(vtkCommand::MiddleButtonReleaseEvent,
                                          vtkWidgetEvent::EndTranslate,
                                          this, vtkLineWidget2::EndSelectAction);
  this->CallbackMapper->SetCallbackMethod(vtkCommand::RightButtonPressEvent,
                                          vtkWidgetEvent::Scale,
                                          this, vtkLineWidget2::ScaleAction);
  this->CallbackMapper->SetCallbackMethod(vtkCommand::RightButtonReleaseEvent,
                                          vtkWidgetEvent::EndScale,
                                          this, vtkLineWidget2::EndSelectAction);
  this->CallbackMapper->SetCallbackMethod(vtkCommand::MouseMoveEvent,
                                          vtkWidgetEvent::Move,
                                          this, vtkLineWidget2::MoveAction);

  this->ActiveKeyCode = 0;
  this->KeyEventCallbackCommand = vtkCallbackCommand::New();
  this->KeyEventCallbackCommand->SetClientData(this);
  this->KeyEventCallbackCommand->SetCallback(vtkLineWidget2::ProcessKeyEvents);
}

//----------------------------------------------------------------------------
vtkLineWidget2::~vtkLineWidget2()
{
  this->Point1Widget->Delete();
  this->Point2Widget->Delete();
  this->LineHandle->Delete();
  this->KeyEventCallbackCommand->Delete();
}

//----------------------------------------------------------------------
void vtkLineWidget2::SetEnabled(int enabling)
{
  int enabled = this->Enabled;

  // We do this step first because it sets the CurrentRenderer
  this->Superclass::SetEnabled(enabling);

  // We defer enabling the handles until the selection process begins
  if ( enabling && !enabled )
  {
    // Don't actually turn these on until cursor is near the end points or the line.
    this->CreateDefaultRepresentation();
    this->Point1Widget->SetRepresentation(reinterpret_cast<vtkLineRepresentation*>
                                          (this->WidgetRep)->GetPoint1Representation());
    this->Point1Widget->SetInteractor(this->Interactor);
    this->Point1Widget->GetRepresentation()->SetRenderer(this->CurrentRenderer);

    this->Point2Widget->SetRepresentation(reinterpret_cast<vtkLineRepresentation*>
                                          (this->WidgetRep)->GetPoint2Representation());
    this->Point2Widget->SetInteractor(this->Interactor);
    this->Point2Widget->GetRepresentation()->SetRenderer(this->CurrentRenderer);

    this->LineHandle->SetRepresentation(reinterpret_cast<vtkLineRepresentation*>
                                          (this->WidgetRep)->GetLineHandleRepresentation());
    this->LineHandle->SetInteractor(this->Interactor);
    this->LineHandle->GetRepresentation()->SetRenderer(this->CurrentRenderer);

    if (this->Parent)
    {
      this->Parent->AddObserver(vtkCommand::KeyPressEvent,
                                this->KeyEventCallbackCommand,
                                this->Priority);
      this->Parent->AddObserver(vtkCommand::KeyReleaseEvent,
                                this->KeyEventCallbackCommand,
                                this->Priority);
    }
    else
    {
      this->Interactor->AddObserver(vtkCommand::KeyPressEvent,
                                    this->KeyEventCallbackCommand,
                                    this->Priority);
      this->Interactor->AddObserver(vtkCommand::KeyReleaseEvent,
                                    this->KeyEventCallbackCommand,
                                    this->Priority);
    }
  }
  else if ( !enabling && enabled )
  {
    this->Point1Widget->SetEnabled(0);
    this->Point2Widget->SetEnabled(0);
    this->LineHandle->SetEnabled(0);

    if (this->Parent)
    {
      this->Parent->RemoveObserver(this->KeyEventCallbackCommand);
    }
    else
    {
      this->Interactor->RemoveObserver(this->KeyEventCallbackCommand);
    }
  }
}

//----------------------------------------------------------------------
void vtkLineWidget2::SelectAction(vtkAbstractWidget *w)
{
  vtkLineWidget2 *self = reinterpret_cast<vtkLineWidget2*>(w);
  if ( self->WidgetRep->GetInteractionState() == vtkLineRepresentation::Outside )
  {
    return;
  }

  // Get the event position
  int X = self->Interactor->GetEventPosition()[0];
  int Y = self->Interactor->GetEventPosition()[1];

  // We are definitely selected
  self->WidgetState = vtkLineWidget2::Active;
  self->GrabFocus(self->EventCallbackCommand);
  double e[2];
  e[0] = static_cast<double>(X);
  e[1] = static_cast<double>(Y);
  reinterpret_cast<vtkLineRepresentation*>(self->WidgetRep)->
    StartWidgetInteraction(e);
  self->InvokeEvent(vtkCommand::LeftButtonPressEvent,nullptr); //for the handles
  self->StartInteraction();
  self->InvokeEvent(vtkCommand::StartInteractionEvent,nullptr);
  self->EventCallbackCommand->SetAbortFlag(1);
}

//----------------------------------------------------------------------
void vtkLineWidget2::TranslateAction(vtkAbstractWidget *w)
{
  vtkLineWidget2 *self = reinterpret_cast<vtkLineWidget2*>(w);
  if ( self->WidgetRep->GetInteractionState() == vtkLineRepresentation::Outside )
  {
    return;
  }

  // Modify the state, we are selected
  int state = self->WidgetRep->GetInteractionState();
  if ( state == vtkLineRepresentation::OnP1 )
  {
    reinterpret_cast<vtkLineRepresentation*>(self->WidgetRep)->
      SetInteractionState(vtkLineRepresentation::TranslatingP1);
  }
  else if ( state == vtkLineRepresentation::OnP2 )
  {
    reinterpret_cast<vtkLineRepresentation*>(self->WidgetRep)->
      SetInteractionState(vtkLineRepresentation::TranslatingP2);
  }
  else
  {
    reinterpret_cast<vtkLineRepresentation*>(self->WidgetRep)->
      SetInteractionState(vtkLineRepresentation::OnLine);
  }

  // Get the event position
  int X = self->Interactor->GetEventPosition()[0];
  int Y = self->Interactor->GetEventPosition()[1];

  // We are definitely selected
  self->WidgetState = vtkLineWidget2::Active;
  self->GrabFocus(self->EventCallbackCommand);
  double eventPos[2];
  eventPos[0] = static_cast<double>(X);
  eventPos[1] = static_cast<double>(Y);
  reinterpret_cast<vtkLineRepresentation*>(self->WidgetRep)->
    StartWidgetInteraction(eventPos);
  self->InvokeEvent(vtkCommand::LeftButtonPressEvent,nullptr); //for the handles
  self->EventCallbackCommand->SetAbortFlag(1);
  self->StartInteraction();
  self->InvokeEvent(vtkCommand::StartInteractionEvent,nullptr);
}

//----------------------------------------------------------------------
void vtkLineWidget2::ScaleAction(vtkAbstractWidget *w)
{
  vtkLineWidget2 *self = reinterpret_cast<vtkLineWidget2*>(w);
  if ( self->WidgetRep->GetInteractionState() == vtkLineRepresentation::Outside )
  {
    return;
  }

  reinterpret_cast<vtkLineRepresentation*>(self->WidgetRep)->
    SetInteractionState(vtkLineRepresentation::Scaling);
  self->Interactor->Disable();
  self->LineHandle->SetEnabled(0);
  self->Interactor->Enable();

  // Get the event position
  int X = self->Interactor->GetEventPosition()[0];
  int Y = self->Interactor->GetEventPosition()[1];

  // We are definitely selected
  self->WidgetState = vtkLineWidget2::Active;
  self->GrabFocus(self->EventCallbackCommand);
  double eventPos[2];
  eventPos[0] = static_cast<double>(X);
  eventPos[1] = static_cast<double>(Y);
  reinterpret_cast<vtkLineRepresentation*>(self->WidgetRep)->
    StartWidgetInteraction(eventPos);
  self->EventCallbackCommand->SetAbortFlag(1);
  self->StartInteraction();
  self->InvokeEvent(vtkCommand::StartInteractionEvent,nullptr);
}

//----------------------------------------------------------------------
void vtkLineWidget2::MoveAction(vtkAbstractWidget *w)
{
  vtkLineWidget2 *self = reinterpret_cast<vtkLineWidget2*>(w);
  // compute some info we need for all cases
  int X = self->Interactor->GetEventPosition()[0];
  int Y = self->Interactor->GetEventPosition()[1];

  // See whether we're active
  if ( self->WidgetState == vtkLineWidget2::Start )
  {
    self->Interactor->Disable(); //avoid extra renders
    self->Point1Widget->SetEnabled(0);
    self->Point2Widget->SetEnabled(0);
    self->LineHandle->SetEnabled(0);

    int oldState = self->WidgetRep->GetInteractionState();
    int state = self->WidgetRep->ComputeInteractionState(X,Y);
    int changed;
    // Determine if we are near the end points or the line
    if ( state == vtkLineRepresentation::Outside )
    {
      changed = self->RequestCursorShape(VTK_CURSOR_DEFAULT);
    }
    else //must be near something
    {
      changed = self->RequestCursorShape(VTK_CURSOR_HAND);
      if ( state == vtkLineRepresentation::OnP1 )
      {
        self->Point1Widget->SetEnabled(1);
      }
      else if ( state == vtkLineRepresentation::OnP2 )
      {
        self->Point2Widget->SetEnabled(1);
      }
      else //if ( state == vtkLineRepresentation::OnLine )
      {
        self->LineHandle->SetEnabled(1);
        changed = 1; //movement along the line always needs render
      }
    }
    self->Interactor->Enable(); //avoid extra renders
    if ( changed || oldState != state )
    {
      self->Render();
    }
  }
  else //if ( self->WidgetState == vtkLineWidget2::Active )
  {
    // moving something
    double e[2];
    e[0] = static_cast<double>(X);
    e[1] = static_cast<double>(Y);
    self->InvokeEvent(vtkCommand::MouseMoveEvent,nullptr); //handles observe this
    reinterpret_cast<vtkLineRepresentation*>(self->WidgetRep)->
      WidgetInteraction(e);
    self->InvokeEvent(vtkCommand::InteractionEvent,nullptr);
    self->EventCallbackCommand->SetAbortFlag(1);
    self->Render();
  }
}

//----------------------------------------------------------------------
void vtkLineWidget2::EndSelectAction(vtkAbstractWidget *w)
{
  vtkLineWidget2 *self = reinterpret_cast<vtkLineWidget2*>(w);
  if ( self->WidgetState == vtkLineWidget2::Start )
  {
    return;
  }

  // Return state to not active
  self->WidgetState = vtkLineWidget2::Start;
  self->ReleaseFocus();
  self->InvokeEvent(vtkCommand::LeftButtonReleaseEvent,nullptr); //handles observe this
  self->EventCallbackCommand->SetAbortFlag(1);
  self->InvokeEvent(vtkCommand::EndInteractionEvent,nullptr);
  self->Superclass::EndInteraction();
  self->Render();
}

//----------------------------------------------------------------------
void vtkLineWidget2::CreateDefaultRepresentation()
{
  if ( ! this->WidgetRep )
  {
    this->WidgetRep = vtkLineRepresentation::New();
  }
}

//----------------------------------------------------------------------------
void vtkLineWidget2::SetProcessEvents(int pe)
{
  this->Superclass::SetProcessEvents(pe);

  this->Point1Widget->SetProcessEvents(pe);
  this->Point2Widget->SetProcessEvents(pe);
  this->LineHandle->SetProcessEvents(pe);
}

//----------------------------------------------------------------------------
void vtkLineWidget2::ProcessKeyEvents(vtkObject* , unsigned long event,
                                      void* clientdata, void* )
{
  vtkLineWidget2 *self = static_cast<vtkLineWidget2*>(clientdata);
  vtkRenderWindowInteractor *iren = self->GetInteractor();
  switch (event)
  {
    case vtkCommand::KeyPressEvent:
      if (self->ActiveKeyCode == 0)
      {
        self->ActiveKeyCode = iren->GetKeyCode();
      }
      break;
    case vtkCommand::KeyReleaseEvent:
      if (self->ActiveKeyCode == iren->GetKeyCode())
      {
        self->ActiveKeyCode = 0;
      }
      break;
    default:
      break;
  }

  vtkLineRepresentation *rep = vtkLineRepresentation::SafeDownCast(self->WidgetRep);
  switch (self->ActiveKeyCode)
  {
    case 'x':
    case 'X':
      rep->SetRestrictFlag(vtkLineRepresentation::RestrictToX);
      break;
    case 'y':
    case 'Y':
      rep->SetRestrictFlag(vtkLineRepresentation::RestrictToY);
      break;
    case 'z':
    case 'Z':
      rep->SetRestrictFlag(vtkLineRepresentation::RestrictToZ);
      break;
    default:
      rep->SetRestrictFlag(vtkLineRepresentation::RestrictNone);
      break;
  }
}

//----------------------------------------------------------------------------
void vtkLineWidget2::PrintSelf(ostream& os, vtkIndent indent)
{
  this->Superclass::PrintSelf(os,indent);

}