/*
 *  This file is part of RawTherapee.
 *
 *  RawTherapee is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 * 
 *  RawTherapee 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 General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with RawTherapee.  If not, see <http://www.gnu.org/licenses/>.
 *
 *  2010 Ilya Popov <ilia_popov@rambler.ru>
 *  2012 Emil Martinec <ejmartin@uchicago.edu>
 */

#ifndef CPLX_WAVELET_DEC_H_INCLUDED
#define CPLX_WAVELET_DEC_H_INCLUDED

#include <cstddef>
#include <math.h>

#include "cplx_wavelet_level.h"
#include "cplx_wavelet_filter_coeffs.h"

namespace rtengine {

	class wavelet_decomposition
	{
	public:

		typedef float internal_type;
		float *coeff0;
		bool memoryAllocationFailed;

	private:

		static const int maxlevels = 10;//should be greater than any conceivable order of decimation

		int lvltot, subsamp;
		int numThreads;
		int m_w, m_h;//dimensions

		int wavfilt_len, wavfilt_offset;
		float *wavfilt_anal;
		float *wavfilt_synth;


		wavelet_level<internal_type> * wavelet_decomp[maxlevels];

	public:

		template<typename E>
		wavelet_decomposition(E * src, int width, int height, int maxlvl, int subsampling, int skipcrop = 1, int numThreads = 1, int Daub4Len = 6);

		~wavelet_decomposition();

		internal_type ** level_coeffs(int level) const
		{
			return wavelet_decomp[level]->subbands();
		}

		int level_W(int level) const
		{
			return wavelet_decomp[level]->width();
		}

		int level_H(int level) const
		{
			return wavelet_decomp[level]->height();
		}

		int level_stride(int level) const
		{
			return wavelet_decomp[level]->stride();
		}

		int maxlevel() const
		{
			return lvltot+1;
		}

		int subsample() const
		{
			return subsamp;
		}
		template<typename E>
		void reconstruct(E * dst, const float blend = 1.f);
	};

	template<typename E>
	wavelet_decomposition::wavelet_decomposition(E * src, int width, int height, int maxlvl, int subsampling, int skipcrop, int numThreads, int Daub4Len)
	: coeff0(NULL), memoryAllocationFailed(false), lvltot(0), subsamp(subsampling), numThreads(numThreads), m_w(width), m_h(height)
	{

		//initialize wavelet filters
		wavfilt_len = Daub4Len;
		wavfilt_offset = Daub4_offset;
		wavfilt_anal = new float[2*wavfilt_len];
		wavfilt_synth = new float[2*wavfilt_len];

		if(wavfilt_len==6) {
			for (int n=0; n<2; n++) {
				for (int i=0; i<wavfilt_len; i++) {
					wavfilt_anal[wavfilt_len*(n)+i]  = Daub4_anal[n][i];
					wavfilt_synth[wavfilt_len*(n)+i] = Daub4_anal[n][wavfilt_len-1-i];
					//n=0 lopass, n=1 hipass
				}
			}
		} else if(wavfilt_len==8) {
			for (int n=0; n<2; n++) {
				for (int i=0; i<wavfilt_len; i++) {
					wavfilt_anal[wavfilt_len*(n)+i]  = Daub4_anal8[n][i];
					wavfilt_synth[wavfilt_len*(n)+i] = Daub4_anal8[n][wavfilt_len-1-i];
					//n=0 lopass, n=1 hipass
				}
			}
		}	
		else if(wavfilt_len==12) {
			for (int n=0; n<2; n++) {
				for (int i=0; i<wavfilt_len; i++) {
					wavfilt_anal[wavfilt_len*(n)+i]  = Daub4_anal12[n][i];
					wavfilt_synth[wavfilt_len*(n)+i] = Daub4_anal12[n][wavfilt_len-1-i];
					//n=0 lopass, n=1 hipass
				}
			}
		}	
		else if(wavfilt_len==16) {
			for (int n=0; n<2; n++) {
				for (int i=0; i<wavfilt_len; i++) {
					wavfilt_anal[wavfilt_len*(n)+i]  = Daub4_anal16[n][i];
					wavfilt_synth[wavfilt_len*(n)+i] = Daub4_anal16[n][wavfilt_len-1-i];
					//n=0 lopass, n=1 hipass
				}
			}
		}	
		else if(wavfilt_len==4) {
			for (int n=0; n<2; n++) {
				for (int i=0; i<wavfilt_len; i++) {
					wavfilt_anal[wavfilt_len*(n)+i]  = Daub4_anal0[n][i];
					wavfilt_synth[wavfilt_len*(n)+i] = Daub4_anal0[n][wavfilt_len-1-i];
					//n=0 lopass, n=1 hipass
				}
			}
		}
		// after coefficient rotation, data structure is:
		// wavelet_decomp[scale][channel={lo,hi1,hi2,hi3}][pixel_array]

		lvltot=0;
		E *buffer[2];
		buffer[0] = new (std::nothrow) E[(m_w/2+1)*(m_h/2+1)];
		if(buffer[0] == NULL) {
			memoryAllocationFailed = true;
			return;
		}
		buffer[1] = new (std::nothrow) E[(m_w/2+1)*(m_h/2+1)];
		if(buffer[1] == NULL) {
			memoryAllocationFailed = true;
			delete[] buffer[0];
			buffer[0] = NULL;
			return;
		}
		int bufferindex = 0;

		wavelet_decomp[lvltot] = new wavelet_level<internal_type>(src, buffer[bufferindex^1], lvltot/*level*/, subsamp, m_w, m_h, \
																  wavfilt_anal, wavfilt_anal, wavfilt_len, wavfilt_offset, skipcrop, numThreads);
		if(wavelet_decomp[lvltot]->memoryAllocationFailed)
			memoryAllocationFailed = true;
		while(lvltot < maxlvl-1) {
			lvltot++;
			bufferindex ^= 1;
			wavelet_decomp[lvltot] = new wavelet_level<internal_type>(buffer[bufferindex], buffer[bufferindex^1]/*lopass*/, lvltot/*level*/, subsamp, \
																	  wavelet_decomp[lvltot-1]->width(), wavelet_decomp[lvltot-1]->height(), \
																	  wavfilt_anal, wavfilt_anal, wavfilt_len, wavfilt_offset, skipcrop, numThreads);
			if(wavelet_decomp[lvltot]->memoryAllocationFailed)
				memoryAllocationFailed = true;
		}
		coeff0 = buffer[bufferindex^1];
		delete[] buffer[bufferindex];
	}
	
	template<typename E>
	void wavelet_decomposition::reconstruct(E * dst, const float blend) { 

		if(memoryAllocationFailed)
			return;
		// data structure is wavcoeffs[scale][channel={lo,hi1,hi2,hi3}][pixel_array]

		if(lvltot >= 1) {
			int width = wavelet_decomp[1]->m_w;
			int height = wavelet_decomp[1]->m_h;

			E *tmpHi = new (std::nothrow) E[width*height];
			if(tmpHi == NULL) {
				memoryAllocationFailed = true;
				return;
			}

			for (int lvl=lvltot; lvl>0; lvl--) {
				E *tmpLo = wavelet_decomp[lvl]->wavcoeffs[2]; // we can use this as buffer
				wavelet_decomp[lvl]->reconstruct_level(tmpLo, tmpHi, coeff0, coeff0, wavfilt_synth, wavfilt_synth, wavfilt_len, wavfilt_offset);
				delete wavelet_decomp[lvl];
				wavelet_decomp[lvl] = NULL;
			}
			delete[] tmpHi;
		}

		int width = wavelet_decomp[0]->m_w;
		int height = wavelet_decomp[0]->m_h2;
		E *tmpLo;
		if(wavelet_decomp[0]->bigBlockOfMemoryUsed()) // bigBlockOfMemoryUsed means that wavcoeffs[2] points to a block of memory big enough to hold the data
			tmpLo = wavelet_decomp[0]->wavcoeffs[2];
		else {										  // allocate new block of memory
			tmpLo = new (std::nothrow) E[width*height];
			if(tmpLo == NULL) {
				memoryAllocationFailed = true;
				return;
			}
		}
		E *tmpHi = new (std::nothrow) E[width*height];
		if(tmpHi == NULL) {
			memoryAllocationFailed = true;
			if(!wavelet_decomp[0]->bigBlockOfMemoryUsed())
				delete[] tmpLo;
			return;
		}


		wavelet_decomp[0]->reconstruct_level(tmpLo, tmpHi, coeff0, dst, wavfilt_synth, wavfilt_synth, wavfilt_len, wavfilt_offset, blend);
		if(!wavelet_decomp[0]->bigBlockOfMemoryUsed())
			delete[] tmpLo;
		delete[] tmpHi;
		delete wavelet_decomp[0];
		wavelet_decomp[0] = NULL;
		delete[] coeff0;
		coeff0 = NULL;
	}

};

#endif