/***************************************************************************
 *                                                                         *
 *   LinuxSampler - modular, streaming capable sampler                     *
 *                                                                         *
 *   Copyright (C) 2003, 2004 by Benno Senoner and Christian Schoenebeck   *
 *   Copyright (C) 2005 Christian Schoenebeck                              *
 *                                                                         *
 *   This program 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 2 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 General Public License for more details.                          *
 *                                                                         *
 *   You should have received a copy of the GNU General Public License     *
 *   along with this program; if not, write to the Free Software           *
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston,                 *
 *   MA  02111-1307  USA                                                   *
 ***************************************************************************/

#ifndef __LS_GIG_SYNTHESIZER_H__
#define __LS_GIG_SYNTHESIZER_H__

#include "../../common/global.h"
#include "../../common/RTMath.h"
#include "../common/Resampler.h"
#include "../common/BiquadFilter.h"
#include "Filter.h"
#include "SynthesisParam.h"

#define SYNTHESIS_MODE_SET_INTERPOLATE(iMode,bVal)      if (bVal) iMode |= 0x01; else iMode &= ~0x01   /* (un)set mode bit 0 */
#define SYNTHESIS_MODE_SET_FILTER(iMode,bVal)           if (bVal) iMode |= 0x02; else iMode &= ~0x02   /* (un)set mode bit 1 */
#define SYNTHESIS_MODE_SET_LOOP(iMode,bVal)             if (bVal) iMode |= 0x04; else iMode &= ~0x04   /* (un)set mode bit 2 */
#define SYNTHESIS_MODE_SET_CHANNELS(iMode,bVal)         if (bVal) iMode |= 0x08; else iMode &= ~0x08   /* (un)set mode bit 3 */
#define SYNTHESIS_MODE_SET_IMPLEMENTATION(iMode,bVal)   if (bVal) iMode |= 0x10; else iMode &= ~0x10   /* (un)set mode bit 4 */
#define SYNTHESIS_MODE_SET_PROFILING(iMode,bVal)        if (bVal) iMode |= 0x20; else iMode &= ~0x20   /* (un)set mode bit 5 */

#define SYNTHESIS_MODE_GET_INTERPOLATE(iMode)           iMode & 0x01
#define SYNTHESIS_MODE_GET_FILTER(iMode)                iMode & 0x02
#define SYNTHESIS_MODE_GET_LOOP(iMode)                  iMode & 0x04
#define SYNTHESIS_MODE_GET_CHANNELS(iMode)              iMode & 0x08
#define SYNTHESIS_MODE_GET_IMPLEMENTATION(iMode)        iMode & 0x10

namespace LinuxSampler { namespace gig {

    typedef void SynthesizeFragment_Fn(SynthesisParam* pFinalParam, Loop* pLoop);

    void* GetSynthesisFunction(const int SynthesisMode);
    void RunSynthesisFunction(const int SynthesisMode, SynthesisParam* pFinalParam, Loop* pLoop);

    enum channels_t {
        MONO,
        STEREO
    };

    /** @brief Main Synthesis algorithms for the gig::Engine
     *
     * Implementation of the main synthesis algorithms of the Gigasampler
     * format capable sampler engine. This means resampling / interpolation
     * for pitching the audio signal, looping, filter and amplification.
     */
    template<channels_t CHANNELS, bool DOLOOP, bool USEFILTER, bool INTERPOLATE>
    class Synthesizer : public __RTMath<CPP>, public LinuxSampler::Resampler<INTERPOLATE> {

            // declarations of derived functions (see "Name lookup,
            // templates, and accessing members of base classes" in
            // the gcc manual for an explanation of why this is
            // needed).
            using __RTMath<CPP>::Mul;
            using __RTMath<CPP>::Float;
            //using LinuxSampler::Resampler<INTERPOLATE>::GetNextSampleMonoCPP;
            //using LinuxSampler::Resampler<INTERPOLATE>::GetNextSampleStereoCPP;
            using LinuxSampler::Resampler<INTERPOLATE>::Interpolate1StepMonoCPP;
            using LinuxSampler::Resampler<INTERPOLATE>::Interpolate1StepStereoCPP;

        public:
        //protected:

            static void SynthesizeSubFragment(SynthesisParam* pFinalParam, Loop* pLoop) {
                if (DOLOOP) {
                    const float fLoopEnd   = Float(pLoop->uiEnd);
                    const float fLoopStart = Float(pLoop->uiStart);
                    const float fLoopSize  = Float(pLoop->uiSize);
                    if (pLoop->uiTotalCycles) {
                        // render loop (loop count limited)
                        for (; pFinalParam->uiToGo > 0 && pLoop->uiCyclesLeft; pLoop->uiCyclesLeft -= WrapLoop(fLoopStart, fLoopSize, fLoopEnd, &pFinalParam->dPos)) {
                            const uint uiToGo = Min(pFinalParam->uiToGo, DiffToLoopEnd(fLoopEnd, &pFinalParam->dPos, pFinalParam->fFinalPitch) + 1); //TODO: instead of +1 we could also round up
                            SynthesizeSubSubFragment(pFinalParam, uiToGo);
                        }
                        // render on without loop
                        SynthesizeSubSubFragment(pFinalParam, pFinalParam->uiToGo);
                    } else { // render loop (endless loop)
                        for (; pFinalParam->uiToGo > 0; WrapLoop(fLoopStart, fLoopSize, fLoopEnd, &pFinalParam->dPos)) {
                            const uint uiToGo = Min(pFinalParam->uiToGo, DiffToLoopEnd(fLoopEnd, &pFinalParam->dPos, pFinalParam->fFinalPitch) + 1); //TODO: instead of +1 we could also round up
                            SynthesizeSubSubFragment(pFinalParam, uiToGo);
                        }
                    }
                } else { // no looping
                    SynthesizeSubSubFragment(pFinalParam, pFinalParam->uiToGo);
                }
            }

            /**
             * Returns the difference to the sample's loop end.
             */
            inline static int DiffToLoopEnd(const float& LoopEnd, const void* Pos, const float& Pitch) {
                return uint((LoopEnd - *((double *)Pos)) / Pitch);
            }

#if 0
            //TODO: this method is not in use yet, it's intended to be used for pitch=x.0f where we could use integer instead of float as playback position variable
            inline static int WrapLoop(const int& LoopStart, const int& LoopSize, const int& LoopEnd, int& Pos) {
                //TODO: we can easily eliminate the branch here
                if (Pos < LoopEnd) return 0;
                Pos = (Pos - LoopEnd) % LoopSize + LoopStart;
                return 1;
            }
#endif

            /**
             * This method handles looping of the RAM playback part of the
             * sample, thus repositioning the playback position once the
             * loop limit was reached. Note: looping of the disk streaming
             * part is handled by libgig (ReadAndLoop() method which will
             * be called by the DiskThread).
             */
            inline static int WrapLoop(const float& LoopStart, const float& LoopSize, const float& LoopEnd, void* vPos) {
                double * Pos = (double *)vPos;
                if (*Pos < LoopEnd) return 0;
                *Pos = fmod(*Pos - LoopEnd, LoopSize) + LoopStart;
                return 1;
            }

            static void SynthesizeSubSubFragment(SynthesisParam* pFinalParam, uint uiToGo) {
                switch (CHANNELS) {
                    case MONO: {
                        if (INTERPOLATE) {
                            if (USEFILTER) {
                                Filter filterL = pFinalParam->filterLeft;
                                sample_t* pSrc = pFinalParam->pSrc;
                                double dPos    = pFinalParam->dPos;
                                float fPitch   = pFinalParam->fFinalPitch;
                                float* pOutL   = pFinalParam->pOutLeft;
                                float* pOutR   = pFinalParam->pOutRight;
                                float fVolumeL = pFinalParam->fFinalVolumeLeft;
                                float fVolumeR = pFinalParam->fFinalVolumeRight;
                                float samplePoint;
                                for (int i = 0; i < uiToGo; ++i) {
                                    samplePoint = Interpolate1StepMonoCPP(pSrc, &dPos, fPitch);
                                    samplePoint = filterL.Apply(samplePoint);
                                    pOutL[i] += samplePoint * fVolumeL;
                                    pOutR[i] += samplePoint * fVolumeR;
                                }
                                pFinalParam->dPos = dPos;
                            } else { // no filter needed
                                sample_t* pSrc = pFinalParam->pSrc;
                                double dPos    = pFinalParam->dPos;
                                float fPitch   = pFinalParam->fFinalPitch;
                                float* pOutL   = pFinalParam->pOutLeft;
                                float* pOutR   = pFinalParam->pOutRight;
                                float fVolumeL = pFinalParam->fFinalVolumeLeft;
                                float fVolumeR = pFinalParam->fFinalVolumeRight;
                                float samplePoint;
                                for (int i = 0; i < uiToGo; ++i) {
                                    samplePoint = Interpolate1StepMonoCPP(pSrc, &dPos, fPitch);
                                    pOutL[i] += samplePoint * fVolumeL;
                                    pOutR[i] += samplePoint * fVolumeR;
                                }
                                pFinalParam->dPos = dPos;
                            }
                        } else { // no interpolation
                            if (USEFILTER) {
                                Filter filterL = pFinalParam->filterLeft;
                                sample_t* pSrc  = pFinalParam->pSrc;
                                float* pOutL   = pFinalParam->pOutLeft;
                                float* pOutR   = pFinalParam->pOutRight;
                                float fVolumeL = pFinalParam->fFinalVolumeLeft;
                                float fVolumeR = pFinalParam->fFinalVolumeRight;
                                int pos_offset = (int) pFinalParam->dPos;
                                float samplePoint;
                                for (int i = 0; i < uiToGo; ++i) {
                                    samplePoint = pSrc[i + pos_offset];
                                    samplePoint = filterL.Apply(samplePoint);
                                    pOutL[i] += samplePoint * fVolumeL;
                                    pOutR[i] += samplePoint * fVolumeR;
                                }
                                pFinalParam->dPos += uiToGo;
                            } else { // no filter needed
                                sample_t* pSrc  = pFinalParam->pSrc;
                                float* pOutL   = pFinalParam->pOutLeft;
                                float* pOutR   = pFinalParam->pOutRight;
                                float fVolumeL = pFinalParam->fFinalVolumeLeft;
                                float fVolumeR = pFinalParam->fFinalVolumeRight;
                                int pos_offset = (int) pFinalParam->dPos;
                                float samplePoint;
                                for (int i = 0; i < uiToGo; ++i) {
                                    samplePoint = pSrc[i + pos_offset];
                                    pOutL[i] += samplePoint * fVolumeL;
                                    pOutR[i] += samplePoint * fVolumeR;
                                }
                                pFinalParam->dPos += uiToGo;
                            }
                        }
                        break;
                    }
                    case STEREO: {
                        if (INTERPOLATE) {
                            if (USEFILTER) {
                                Filter filterL = pFinalParam->filterLeft;
                                Filter filterR = pFinalParam->filterRight;
                                sample_t* pSrc = pFinalParam->pSrc;
                                double dPos    = pFinalParam->dPos;
                                float fPitch   = pFinalParam->fFinalPitch;
                                float* pOutL   = pFinalParam->pOutLeft;
                                float* pOutR   = pFinalParam->pOutRight;
                                float fVolumeL = pFinalParam->fFinalVolumeLeft;
                                float fVolumeR = pFinalParam->fFinalVolumeRight;
                                stereo_sample_t samplePoint;
                                for (int i = 0; i < uiToGo; ++i) {
                                    samplePoint = Interpolate1StepStereoCPP(pSrc, &dPos, fPitch);
                                    samplePoint.left  = filterL.Apply(samplePoint.left);
                                    samplePoint.right = filterR.Apply(samplePoint.right);
                                    pOutL[i] += samplePoint.left  * fVolumeL;
                                    pOutR[i] += samplePoint.right * fVolumeR;
                                }
                                pFinalParam->dPos = dPos;
                            } else { // no filter needed
                                sample_t* pSrc = pFinalParam->pSrc;
                                double dPos    = pFinalParam->dPos;
                                float fPitch   = pFinalParam->fFinalPitch;
                                float* pOutL   = pFinalParam->pOutLeft;
                                float* pOutR   = pFinalParam->pOutRight;
                                float fVolumeL = pFinalParam->fFinalVolumeLeft;
                                float fVolumeR = pFinalParam->fFinalVolumeRight;
                                stereo_sample_t samplePoint;
                                for (int i = 0; i < uiToGo; ++i) {
                                    samplePoint = Interpolate1StepStereoCPP(pSrc, &dPos, fPitch);
                                    pOutL[i] += samplePoint.left  * fVolumeL;
                                    pOutR[i] += samplePoint.right * fVolumeR;
                                }
                                pFinalParam->dPos = dPos;
                            }
                        } else { // no interpolation
                            if (USEFILTER) {
                                Filter filterL = pFinalParam->filterLeft;
                                Filter filterR = pFinalParam->filterRight;
                                sample_t* pSrc  = pFinalParam->pSrc;
                                float* pOutL   = pFinalParam->pOutLeft;
                                float* pOutR   = pFinalParam->pOutRight;
                                float fVolumeL = pFinalParam->fFinalVolumeLeft;
                                float fVolumeR = pFinalParam->fFinalVolumeRight;
                                int pos_offset = ((int) pFinalParam->dPos) << 1;
                                stereo_sample_t samplePoint;
                                for (int i = 0, ii = 0; i < uiToGo; ++i, ii+=2) {
                                    samplePoint.left  = pSrc[ii + pos_offset];
                                    samplePoint.right = pSrc[ii + pos_offset + 1];
                                    samplePoint.left  = filterL.Apply(samplePoint.left);
                                    samplePoint.right = filterR.Apply(samplePoint.right);
                                    pOutL[i] += samplePoint.left  * fVolumeL;
                                    pOutR[i] += samplePoint.right * fVolumeR;
                                }
                                pFinalParam->dPos += uiToGo;
                            } else { // no filter needed
                                sample_t* pSrc  = pFinalParam->pSrc;
                                float* pOutL   = pFinalParam->pOutLeft;
                                float* pOutR   = pFinalParam->pOutRight;
                                float fVolumeL = pFinalParam->fFinalVolumeLeft;
                                float fVolumeR = pFinalParam->fFinalVolumeRight;
                                int pos_offset = ((int) pFinalParam->dPos) << 1;
                                stereo_sample_t samplePoint;
                                for (int i = 0, ii = 0; i < uiToGo; ++i, ii+=2) {
                                    samplePoint.left  = pSrc[ii + pos_offset];
                                    samplePoint.right = pSrc[ii + pos_offset + 1];
                                    pOutL[i] += samplePoint.left  * fVolumeL;
                                    pOutR[i] += samplePoint.right * fVolumeR;
                                }
                                pFinalParam->dPos += uiToGo;
                            }
                        }
                        break;
                    }
                }
                pFinalParam->pOutRight += uiToGo;
                pFinalParam->pOutLeft  += uiToGo;
                pFinalParam->uiToGo    -= uiToGo;
            }
    };

}} // namespace LinuxSampler::gig

#endif // __LS_GIG_SYNTHESIZER_H__