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 *
 * Licensed to the Apache Software Foundation (ASF) under one
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 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
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#include "precompiled_sd.hxx"

#include "SlsLayeredDevice.hxx"

#include <vcl/window.hxx>
#include <vcl/virdev.hxx>

#include <boost/bind.hpp>
#include <boost/function.hpp>


namespace sd { namespace slidesorter { namespace view {

namespace {
static const sal_Int32 gnMaximumLayerCount = 8;

class LayerInvalidator : public ILayerInvalidator
{
public:
	LayerInvalidator (
		const ::boost::shared_ptr<LayeredDevice>& rpLayeredDevice,
		const SharedSdWindow& rpTargetWindow,
		const int nLayer)
		: mpLayeredDevice(rpLayeredDevice),
		  mpTargetWindow(rpTargetWindow),
		  mnLayer(nLayer)
	{
	}

	virtual void Invalidate (const Rectangle& rInvalidationBox)
	{
		mpLayeredDevice->Invalidate(rInvalidationBox, mnLayer);
		mpTargetWindow->Invalidate(rInvalidationBox);
	}

private:
	const ::boost::shared_ptr<LayeredDevice> mpLayeredDevice;
	SharedSdWindow mpTargetWindow;
	const int mnLayer;
};

void DeviceCopy (
	OutputDevice& rTargetDevice,
	OutputDevice& rSourceDevice,
	const Rectangle& rBox)
{
	rTargetDevice.DrawOutDev(
		rBox.TopLeft(),
		rBox.GetSize(),
		rBox.TopLeft(),
		rBox.GetSize(),
		rSourceDevice);
}


void ForAllRectangles (const Region& rRegion, ::boost::function<void(const Rectangle&)> aFunction)
{
	OSL_ASSERT(aFunction);
	RectangleVector aRectangles;
	rRegion.GetRegionRectangles(aRectangles);

	if(0 == aRectangles.size())
	{
		aFunction(Rectangle());
	}
	else
	{
		for(RectangleVector::const_iterator aRectIter(aRectangles.begin()); aRectIter != aRectangles.end(); aRectIter++)
		{
			aFunction(*aRectIter);
		}

		//Region aMutableRegionCopy (rRegion);
		//RegionHandle aHandle(aMutableRegionCopy.BeginEnumRects());
		//Rectangle aBox;
		//while (aMutableRegionCopy.GetEnumRects(aHandle, aBox))
		//	aFunction(aBox);
		//aMutableRegionCopy.EndEnumRects(aHandle);
	}
}

class Layer : private ::boost::noncopyable
{
public:
	Layer (void);
	~Layer (void);

	void Initialize (const SharedSdWindow& rpTargetWindow);
	void InvalidateRectangle (const Rectangle& rInvalidationBox);
	void InvalidateRegion (const Region& rInvalidationRegion);
	void Validate (const MapMode& rMapMode);
	void Repaint (
		OutputDevice& rTargetDevice,
		const Rectangle& rRepaintRectangle);
	void Resize (const Size& rSize);
	void AddPainter (const SharedILayerPainter& rpPainter);
	void RemovePainter (const SharedILayerPainter& rpPainter);
	bool HasPainter (void) const;
	void Dispose (void);

private:
	::boost::shared_ptr<VirtualDevice> mpLayerDevice;
	::std::vector<SharedILayerPainter> maPainters;
	Region maInvalidationRegion;

	void ValidateRectangle (const Rectangle& rBox);
};
typedef ::boost::shared_ptr<Layer> SharedLayer;


} // end of anonymous namespace


class LayeredDevice::LayerContainer : public ::std::vector<SharedLayer>
{
public:
	LayerContainer (void) {}
	~LayerContainer (void) {}
};




//===== LayeredDevice =========================================================

LayeredDevice::LayeredDevice (const SharedSdWindow& rpTargetWindow)
	: mpTargetWindow(rpTargetWindow),
	  mpLayers(new LayerContainer()),
	  mpBackBuffer(new VirtualDevice(*mpTargetWindow)),
	  maSavedMapMode(rpTargetWindow->GetMapMode())
{
	mpBackBuffer->SetOutputSizePixel(mpTargetWindow->GetSizePixel());
}




LayeredDevice::~LayeredDevice (void)
{
}




void LayeredDevice::Invalidate (
	const Rectangle& rInvalidationArea,
	const sal_Int32 nLayer)
{
	if (nLayer<0 || size_t(nLayer)>=mpLayers->size())
	{
		OSL_ASSERT(nLayer>=0 && size_t(nLayer)<mpLayers->size());
		return;
	}

	(*mpLayers)[nLayer]->InvalidateRectangle(rInvalidationArea);
}




void LayeredDevice::InvalidateAllLayers (const Rectangle& rInvalidationArea)
{
	for (sal_uInt32 nLayer=0; nLayer<mpLayers->size(); ++nLayer)
		(*mpLayers)[nLayer]->InvalidateRectangle(rInvalidationArea);
}




void LayeredDevice::InvalidateAllLayers (const Region& rInvalidationRegion)
{
	for (sal_uInt32 nLayer=0; nLayer<mpLayers->size(); ++nLayer)
		(*mpLayers)[nLayer]->InvalidateRegion(rInvalidationRegion);
}




void LayeredDevice::RegisterPainter (
	const SharedILayerPainter& rpPainter,
	const sal_Int32 nLayer)
{
	OSL_ASSERT(mpLayers);
	if ( ! rpPainter)
	{
		OSL_ASSERT(rpPainter);
		return;
	}
	if (nLayer<0 || nLayer>=gnMaximumLayerCount)
	{
		OSL_ASSERT(nLayer>=0 && nLayer<gnMaximumLayerCount);
		return;
	}

	// Provide the layers.
	if (sal_uInt32(nLayer) >= mpLayers->size())
	{
		const sal_Int32 nOldLayerCount (mpLayers->size());
		mpLayers->resize(nLayer+1);

		for (size_t nIndex=nOldLayerCount; nIndex<mpLayers->size(); ++nIndex)
			(*mpLayers)[nIndex].reset(new Layer());
	}

	(*mpLayers)[nLayer]->AddPainter(rpPainter);
	if (nLayer == 0)
		(*mpLayers)[nLayer]->Initialize(mpTargetWindow);

	rpPainter->SetLayerInvalidator(
		SharedILayerInvalidator(new LayerInvalidator(shared_from_this(),mpTargetWindow,nLayer)));
}




void LayeredDevice::RemovePainter (
	const SharedILayerPainter& rpPainter,
	const sal_Int32 nLayer)
{
	if ( ! rpPainter)
	{
		OSL_ASSERT(rpPainter);
		return;
	}
	if (nLayer<0 || size_t(nLayer)>=mpLayers->size())
	{
		OSL_ASSERT(nLayer>=0 && size_t(nLayer)<mpLayers->size());
		return;
	}

	rpPainter->SetLayerInvalidator(SharedILayerInvalidator());

	(*mpLayers)[nLayer]->RemovePainter(rpPainter);

	// Remove top most layers that do not contain any painters.
	while ( ! mpLayers->empty() && ! mpLayers->back()->HasPainter())
		mpLayers->erase(mpLayers->end()-1);
}




bool LayeredDevice::HasPainter (const sal_Int32 nLayer)
{
	return nLayer>=0
		&& sal_uInt32(nLayer)<mpLayers->size()
		&& (*mpLayers)[nLayer]->HasPainter();
}




void LayeredDevice::Repaint (const Region& rRepaintRegion)
{
	// Validate the contents of all layers (that have their own devices.)
	::std::for_each(
		mpLayers->begin(),
		mpLayers->end(),
		::boost::bind(&Layer::Validate, _1, mpTargetWindow->GetMapMode()));

	ForAllRectangles(rRepaintRegion, ::boost::bind(&LayeredDevice::RepaintRectangle, this, _1));
}




void LayeredDevice::RepaintRectangle (const Rectangle& rRepaintRectangle)
{
	if (mpLayers->size() == 0)
		return;
	else if (mpLayers->size() == 1)
	{
		// Just copy the main layer into the target device.
		(*mpLayers)[0]->Repaint(*mpTargetWindow, rRepaintRectangle);
	}
	else
	{
		// Paint all layers first into the back buffer (to avoid flickering
		// due to synchronous paints) and then copy that into the target
		// device.
		mpBackBuffer->SetMapMode(mpTargetWindow->GetMapMode());
		::std::for_each(
			mpLayers->begin(),
			mpLayers->end(),
			::boost::bind(&Layer::Repaint, _1, ::boost::ref(*mpBackBuffer), rRepaintRectangle));

		DeviceCopy(*mpTargetWindow, *mpBackBuffer, rRepaintRectangle);
	}
}




void LayeredDevice::Resize (void)
{
	const Size aSize (mpTargetWindow->GetSizePixel());
	mpBackBuffer->SetOutputSizePixel(aSize);
	::std::for_each(mpLayers->begin(), mpLayers->end(), ::boost::bind(&Layer::Resize, _1, aSize));
}




void LayeredDevice::Dispose (void)
{
	::std::for_each(mpLayers->begin(), mpLayers->end(), ::boost::bind(&Layer::Dispose, _1));
	mpLayers->clear();
}




bool LayeredDevice::HandleMapModeChange (void)
{
	const MapMode& rMapMode (mpTargetWindow->GetMapMode());
	if (maSavedMapMode == rMapMode)
		return false;

	const Rectangle aLogicWindowBox (
		mpTargetWindow->PixelToLogic(Rectangle(Point(0,0), mpTargetWindow->GetSizePixel())));
	if (maSavedMapMode.GetScaleX() != rMapMode.GetScaleX()
		|| maSavedMapMode.GetScaleY() != rMapMode.GetScaleY()
		|| maSavedMapMode.GetMapUnit() != rMapMode.GetMapUnit())
	{
		// When the scale has changed then we have to paint everything.
		InvalidateAllLayers(aLogicWindowBox);
	}
	else if (maSavedMapMode.GetOrigin() != rMapMode.GetOrigin())
	{
		// Window has been scrolled. Adapt contents of backbuffers and
		// layer devices.
		const Point aDelta (rMapMode.GetOrigin() - maSavedMapMode.GetOrigin());
		mpBackBuffer->CopyArea(
			aLogicWindowBox.TopLeft(),
			mpTargetWindow->PixelToLogic(Point(0,0), maSavedMapMode),
			aLogicWindowBox.GetSize());

		// Invalidate the area(s) that have been exposed.
		const Rectangle aWindowBox (Point(0,0), mpTargetWindow->GetSizePixel());
		if (aDelta.Y() < 0)
			InvalidateAllLayers(mpTargetWindow->PixelToLogic(Rectangle(
				aWindowBox.Left(),
				aWindowBox.Bottom()+aDelta.Y(),
				aWindowBox.Right(),
				aWindowBox.Bottom())));
		else if (aDelta.Y() > 0)
			InvalidateAllLayers(mpTargetWindow->PixelToLogic(Rectangle(
				aWindowBox.Left(),
				aWindowBox.Top(),
				aWindowBox.Right(),
				aWindowBox.Top()+aDelta.Y())));
		if (aDelta.X() < 0)
			InvalidateAllLayers(mpTargetWindow->PixelToLogic(Rectangle(
				aWindowBox.Right()+aDelta.X(),
				aWindowBox.Top(),
				aWindowBox.Right(),
				aWindowBox.Bottom())));
		else if (aDelta.X() > 0)
			InvalidateAllLayers(mpTargetWindow->PixelToLogic(Rectangle(
				aWindowBox.Left(),
				aWindowBox.Top(),
				aWindowBox.Left()+aDelta.X(),
				aWindowBox.Bottom())));
	}
	else
	{
		// Can this happen? Let's trigger a warning when it does.
		OSL_ASSERT(false);
	}

	maSavedMapMode = rMapMode;

	return true;
}




//===== Layer =================================================================

Layer::Layer (void)
	: mpLayerDevice(),
	  maPainters(),
	  maInvalidationRegion()
{
}




Layer::~Layer (void)
{
}




void Layer::Initialize (const SharedSdWindow& rpTargetWindow)
{
#if 0
	(void)rpTargetWindow;
#else
	if ( ! mpLayerDevice)
	{
		mpLayerDevice.reset(new VirtualDevice(*rpTargetWindow));
		mpLayerDevice->SetOutputSizePixel(rpTargetWindow->GetSizePixel());
	}
#endif
}




void Layer::InvalidateRectangle (const Rectangle& rInvalidationBox)
{
	maInvalidationRegion.Union(rInvalidationBox);
}




void Layer::InvalidateRegion (const Region& rInvalidationRegion)
{
	maInvalidationRegion.Union(rInvalidationRegion);
}




void Layer::Validate (const MapMode& rMapMode)
{
	if (mpLayerDevice && ! maInvalidationRegion.IsEmpty())
	{
		Region aRegion (maInvalidationRegion);
		maInvalidationRegion.SetEmpty();

		mpLayerDevice->SetMapMode(rMapMode);
		ForAllRectangles(
			aRegion,
			::boost::bind(&Layer::ValidateRectangle, this, _1));
	}
}




void Layer::ValidateRectangle (const Rectangle& rBox)
{
	if ( ! mpLayerDevice)
		return;
	const Region aSavedClipRegion (mpLayerDevice->GetClipRegion());
	mpLayerDevice->IntersectClipRegion(rBox);

	for (::std::vector<SharedILayerPainter>::const_iterator
			  iPainter(maPainters.begin()),
			  iEnd(maPainters.end());
		 iPainter!=iEnd;
		 ++iPainter)
	{
		(*iPainter)->Paint(*mpLayerDevice, rBox);
	}

	mpLayerDevice->SetClipRegion(aSavedClipRegion);
}




void Layer::Repaint (
	OutputDevice& rTargetDevice,
	const Rectangle& rRepaintRectangle)
{
	if (mpLayerDevice)
	{
		DeviceCopy(rTargetDevice, *mpLayerDevice, rRepaintRectangle);
	}
	else
	{
		::std::for_each(
			maPainters.begin(),
			maPainters.end(),
			::boost::bind(&ILayerPainter::Paint,
				_1,
				::boost::ref(rTargetDevice),
				rRepaintRectangle));
	}
}




void Layer::Resize (const Size& rSize)
{
	if (mpLayerDevice)
	{
		mpLayerDevice->SetOutputSizePixel(rSize);
		maInvalidationRegion = Rectangle(Point(0,0), rSize);
	}
}




void Layer::AddPainter (const SharedILayerPainter& rpPainter)
{
	OSL_ASSERT(::std::find(maPainters.begin(), maPainters.end(), rpPainter) == maPainters.end());

	maPainters.push_back(rpPainter);
}




void Layer::RemovePainter (const SharedILayerPainter& rpPainter)
{
	const ::std::vector<SharedILayerPainter>::iterator iPainter (
		::std::find(maPainters.begin(), maPainters.end(), rpPainter));
	if (iPainter != maPainters.end())
	{
		maPainters.erase(iPainter);
	}
	else
	{
		DBG_ASSERT(false,"LayeredDevice::RemovePainter called for painter that is not registered");
	}
}




bool Layer::HasPainter (void) const
{
	return !maPainters.empty();
}




void Layer::Dispose (void)
{
	maPainters.clear();
}


} } } // end of namespace ::sd::slidesorter::view