#include "stdfx.h"
#include "tfxparam.h"

namespace
{
template <typename T, typename PIXEL>
void prepare_lut(int levels, std::vector<T> &lut)
{
	int i, j;
	int valuestep = PIXEL::maxChannelValue / (levels - 1);
	int step = PIXEL::maxChannelValue / levels;
	for (j = 0; j < levels; j++)
		for (i = 0; i <= step; i++)
			lut[i + j * step] = j * valuestep;
}
}

//===================================================================

class PosterizeFx : public TStandardRasterFx
{
	FX_PLUGIN_DECLARATION(PosterizeFx)

	TRasterFxPort m_input;
	TDoubleParamP m_levels;

public:
	PosterizeFx()
		: m_levels(7.0)
	{
		bindParam(this, "levels", m_levels);
		addInputPort("Source", m_input);
		m_levels->setValueRange(2.0, 10.0);
	}

	~PosterizeFx(){};

	bool doGetBBox(double frame, TRectD &bBox, const TRenderSettings &info)
	{
		if (m_input.isConnected()) {
			bool ret = m_input->doGetBBox(frame, bBox, info);
			return ret;
		} else {
			bBox = TRectD();
			return false;
		}
	}

	void doCompute(TTile &tile, double frame, const TRenderSettings &ri);

	bool canHandle(const TRenderSettings &info, double frame) { return true; }
};

//-------------------------------------------------------------------

template <typename PIXEL, typename CHANNEL_TYPE>
void doPosterize(TRasterPT<PIXEL> ras, int levels)
{
	std::vector<CHANNEL_TYPE> solarize_lut(PIXEL::maxChannelValue + 1);

	prepare_lut<CHANNEL_TYPE, PIXEL>(levels, solarize_lut);
	int j;
	ras->lock();
	for (j = 0; j < ras->getLy(); j++) {
		PIXEL *pix = ras->pixels(j);
		PIXEL *endPix = pix + ras->getLx();
		while (pix < endPix) {
			pix->r = (CHANNEL_TYPE)(solarize_lut[(int)(pix->r)]);
			pix->g = (CHANNEL_TYPE)(solarize_lut[(int)(pix->g)]);
			pix->b = (CHANNEL_TYPE)(solarize_lut[(int)(pix->b)]);
			*pix++;
		}
	}
	ras->unlock();
}
//-------------------------------------------------------------------

void PosterizeFx::doCompute(TTile &tile, double frame, const TRenderSettings &ri)
{
	if (!m_input.isConnected())
		return;

	m_input->compute(tile, frame, ri);

	int levels = (int)m_levels->getValue(frame);
	TRaster32P raster32 = tile.getRaster();
	if (raster32)
		doPosterize<TPixel32, UCHAR>(raster32, levels);
	else {
		TRaster64P raster64 = tile.getRaster();
		if (raster64)
			doPosterize<TPixel64, USHORT>(raster64, levels);
		else
			throw TException("Brightness&Contrast: unsupported Pixel Type");
	}
}

FX_PLUGIN_IDENTIFIER(PosterizeFx, "posterizeFx");