/**
 * Stone of Orthanc
 * Copyright (C) 2012-2016 Sebastien Jodogne, Medical Physics
 * Department, University Hospital of Liege, Belgium
 * Copyright (C) 2017-2019 Osimis S.A., Belgium
 *
 * This program is free software: you can redistribute it and/or
 * modify it under the terms of the GNU Affero General Public License
 * as published by the Free Software Foundation, either version 3 of
 * the License, or (at your option) any later version.
 *
 * This program 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
 * Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 **/


#pragma once

#include "WorldSceneWidget.h"
#include "../Layers/IVolumeSlicer.h"
#include "../Toolbox/Extent2D.h"
#include "../../Framework/Messages/IObserver.h"

#include <map>

namespace OrthancStone
{
  class SliceViewerWidget :
    public WorldSceneWidget,
    public IObserver,
    public IObservable
  {
  public:
    typedef OriginMessage<MessageType_Widget_GeometryChanged, SliceViewerWidget> GeometryChangedMessage;
    typedef OriginMessage<MessageType_Widget_ContentChanged, SliceViewerWidget> ContentChangedMessage;

    // TODO - Use this message in ReferenceLineSource
    class DisplayedSliceMessage : public OriginMessage<MessageType_SliceViewerWidget_DisplayedSlice, SliceViewerWidget>
    {
    private:
      const Slice& slice_;

    public:
      DisplayedSliceMessage(SliceViewerWidget& origin,
                            const Slice& slice) :
        OriginMessage(origin),
        slice_(slice)
      {
      }

      const Slice& GetSlice() const
      {
        return slice_;
      }
    };

  private:
    class Scene;
    
    typedef std::map<const IVolumeSlicer*, size_t>  LayersIndex;

    bool                         started_;
    LayersIndex                  layersIndex_;
    std::vector<IVolumeSlicer*>  layers_;
    std::vector<RenderStyle>     styles_;
    CoordinateSystem3D           plane_;
    std::auto_ptr<Scene>         currentScene_;
    std::auto_ptr<Scene>         pendingScene_;
    std::vector<bool>            changedLayers_;

    bool LookupLayer(size_t& index /* out */,
                     const IVolumeSlicer& layer) const;

    void GetLayerExtent(Extent2D& extent,
                        IVolumeSlicer& source) const;

    void OnGeometryReady(const IVolumeSlicer::GeometryReadyMessage& message);

    virtual void OnContentChanged(const IVolumeSlicer::ContentChangedMessage& message);

    virtual void OnSliceChanged(const IVolumeSlicer::SliceContentChangedMessage& message);

    virtual void OnLayerReady(const IVolumeSlicer::LayerReadyMessage& message);

    virtual void OnLayerError(const IVolumeSlicer::LayerErrorMessage& message);

    void ObserveLayer(IVolumeSlicer& source);

    void ResetChangedLayers();

  public:
    SliceViewerWidget(MessageBroker& broker, 
                      const std::string& name);

    virtual Extent2D GetSceneExtent();

  protected:
    virtual bool RenderScene(CairoContext& context,
                             const ViewportGeometry& view);

    void ResetPendingScene();

    void UpdateLayer(size_t index,
                     ILayerRenderer* renderer,
                     const CoordinateSystem3D& plane);

    void InvalidateAllLayers();

    void InvalidateLayer(size_t layer);
    
  public:
    virtual ~SliceViewerWidget();

    size_t AddLayer(IVolumeSlicer* layer);  // Takes ownership

    void ReplaceLayer(size_t layerIndex, IVolumeSlicer* layer); // Takes ownership

    void RemoveLayer(size_t layerIndex);

    size_t GetLayerCount() const
    {
      return layers_.size();
    }

    const RenderStyle& GetLayerStyle(size_t layer) const;

    void SetLayerStyle(size_t layer,
                       const RenderStyle& style);

    void SetSlice(const CoordinateSystem3D& plane);

    const CoordinateSystem3D& GetSlice() const
    {
      return plane_;
    }

    virtual bool HasAnimation() const
    {
      return true;
    }

    virtual void DoAnimation();
  };
}