/*//////////////////////////////////////////////////////////////////////////////
// CMT Cosmic Muon Tomography project //////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////

  Copyright (c) 2014, Universita' degli Studi di Padova, INFN sez. di Padova
  All rights reserved

  Authors: Andrea Rigoni Garola < andrea.rigoni@pd.infn.it >

  ------------------------------------------------------------------
  This library is free software;  you  can  redistribute  it  and/or
  modify it  under the  terms  of  the  GNU  Lesser  General  Public
  License as published  by  the  Free  Software  Foundation;  either
  version 3.0 of the License, or (at your option) any later version.

  This library is  distributed in  the hope that it will  be useful,
  but  WITHOUT ANY WARRANTY;  without  even  the implied warranty of
  MERCHANTABILITY  or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  Lesser General Public License for more details.

  You should have received a copy of  the GNU Lesser General  Public
  License along with this library.

//////////////////////////////////////////////////////////////////////////////*/

#include "vtkGeantEvent.h"

#include <vtkPolyData.h>
#include <vtkPoints.h>
#include <vtkCellArray.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkSmartPointer.h>

namespace uLib {
namespace Vtk {

GeantEvent::GeantEvent(Content *content)
    : m_MuonPath(vtkActor::New()), m_Content(content) {
  this->InstallPipe();
  this->Update();
}

GeantEvent::~GeantEvent() {
  m_MuonPath->Delete();
}

vtkPolyData *GeantEvent::GetPolyData() const {
  if (!m_MuonPath || !m_MuonPath->GetMapper())
    return NULL;
  return vtkPolyData::SafeDownCast(m_MuonPath->GetMapper()->GetInput());
}

void GeantEvent::Update() {
  if (!m_Content)
    return;

  vtkSmartPointer<vtkPoints> points = vtkSmartPointer<vtkPoints>::New();
  vtkSmartPointer<vtkCellArray> lines = vtkSmartPointer<vtkCellArray>::New();

  const HLine3f &gen = m_Content->GenVector();
  const Vector<Geant::GeantEvent::Delta> &path = m_Content->Path();

  // Start point from generation vector
  Vector3f currentPos(gen.origin(0), gen.origin(1), gen.origin(2));
  points->InsertNextPoint(currentPos(0), currentPos(1), currentPos(2));

  for (size_t i = 0; i < path.size(); ++i) {
    const Geant::GeantEvent::Delta &delta = path[i];
    
    // P_{i+1} = P_i + Length * Direction
    // Note: HVector3f is stored as (x,y,z,0) in HPoint3f template
    Vector3f dir(delta.Direction()(0), delta.Direction()(1), delta.Direction()(2));
    currentPos += delta.GetLength() * dir;
    
    points->InsertNextPoint(currentPos(0), currentPos(1), currentPos(2));

    vtkIdType line[2] = {static_cast<vtkIdType>(i),
                          static_cast<vtkIdType>(i + 1)};
    lines->InsertNextCell(2, line);
  }

  vtkPolyData *polyData = GetPolyData();
  if (polyData) {
    polyData->SetPoints(points);
    polyData->SetLines(lines);
    polyData->Modified();
  }
}

void GeantEvent::InstallPipe() {
  vtkSmartPointer<vtkPolyData> polyData = vtkSmartPointer<vtkPolyData>::New();
  vtkSmartPointer<vtkPolyDataMapper> mapper =
      vtkSmartPointer<vtkPolyDataMapper>::New();
  mapper->SetInputData(polyData);

  m_MuonPath->SetMapper(mapper);
  
  // Set default look: Red line
  m_MuonPath->GetProperty()->SetColor(1.0, 1.0, 1.0);
  m_MuonPath->GetProperty()->SetLineWidth(1.0);
  m_MuonPath->GetProperty()->SetAmbient(1.0);

  this->SetProp(m_MuonPath);
}

} // namespace Vtk
} // namespace uLib