/************************************************************************
    FAUST Architecture File
    Copyright (C) 2003-2016 GRAME, Centre National de Creation Musicale
    ---------------------------------------------------------------------
    This Architecture section 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.

    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, see <http://www.gnu.org/licenses/>.

    EXCEPTION : As a special exception, you may create a larger work
    that contains this FAUST architecture section and distribute
    that work under terms of your choice, so long as this FAUST
    architecture section is not modified.

 ************************************************************************
 ************************************************************************/

#ifndef __timed_dsp__
#define __timed_dsp__

#include "faust/dsp/dsp.h" 
#include "faust/gui/GUI.h" 
#include "faust/gui/ring-buffer.h"

#include <set>
#include <float.h>
#include <assert.h>

namespace {
    
#if __APPLE__
#if TARGET_OS_IPHONE
    //inline double GetCurrentTimeInUsec() { return double(CAHostTimeBase::GetCurrentTimeInNanos()) / 1000.; }
    // TODO
    inline double GetCurrentTimeInUsec() { return 0.0; }
#else
    #include <CoreAudio/HostTime.h>
    inline double GetCurrentTimeInUsec() { return double(AudioConvertHostTimeToNanos(AudioGetCurrentHostTime())) / 1000.; }
#endif
#endif

#if __linux__
#include <sys/time.h>
inline double GetCurrentTimeInUsec() 
{
    struct timeval tv;
    (void)gettimeofday(&tv, (struct timezone *)NULL);
    return double((tv.tv_sec * 1000000) + tv.tv_usec);
}
#endif

#if _WIN32
#include <Windows.h>
inline double GetCurrentTimeInUsec(void)
{
    LARGE_INTEGER time;
    LARGE_INTEGER frequency;
    QueryPerformanceFrequency(&frequency);
    QueryPerformanceCounter(&time);
    return double(time.QuadPart) / double(frequency.QuadPart) * 1000000.0;
}
#endif
    
}

/**
 * ZoneUI : this class collect zones in a set.
 */

struct ZoneUI : public UI
{
    
    std::set<FAUSTFLOAT*> fZoneSet;
    
    ZoneUI() {};
    virtual ~ZoneUI() {};
    
    void insertZone(FAUSTFLOAT* zone) 
    { 
        if (GUI::gTimedZoneMap.find(zone) != GUI::gTimedZoneMap.end()) {
            fZoneSet.insert(zone);
        } 
    }
    
    // -- widget's layouts
    void openTabBox(const char* label)
    {}
    void openHorizontalBox(const char* label)
    {}
    void openVerticalBox(const char* label)
    {}
    void closeBox()
    {}
    
    // -- active widgets
    void addButton(const char* label, FAUSTFLOAT* zone)
    {
        insertZone(zone);
    }
    void addCheckButton(const char* label, FAUSTFLOAT* zone)
    {
        insertZone(zone);
    }
    void addVerticalSlider(const char* label, FAUSTFLOAT* zone, FAUSTFLOAT init, FAUSTFLOAT fmin, FAUSTFLOAT fmax, FAUSTFLOAT step)
    {
        insertZone(zone);
    }
    void addHorizontalSlider(const char* label, FAUSTFLOAT* zone, FAUSTFLOAT init, FAUSTFLOAT fmin, FAUSTFLOAT fmax, FAUSTFLOAT step)
    {
        insertZone(zone);
    }
    void addNumEntry(const char* label, FAUSTFLOAT* zone, FAUSTFLOAT init, FAUSTFLOAT fmin, FAUSTFLOAT fmax, FAUSTFLOAT step)
    {
        insertZone(zone);
    }
    
    // -- passive widgets
    void addHorizontalBargraph(const char* label, FAUSTFLOAT* zone, FAUSTFLOAT fmin, FAUSTFLOAT fmax)
    {
       insertZone(zone);
    }
    void addVerticalBargraph(const char* label, FAUSTFLOAT* zone, FAUSTFLOAT fmin, FAUSTFLOAT fmax)
    {
        insertZone(zone);
    }
    
    // -- metadata declarations
    void declare(FAUSTFLOAT* zone, const char* key, const char* val)
    {}

};

/**
 * Timed signal processor that allows to handle the decorated DSP by 'slices'
 * that is, calling the 'compute' method several times and changing control
 * parameters between slices.
 */

class timed_dsp : public decorator_dsp {

    protected:
        
        double fDateUsec;       // Compute call date in usec
        double fOffsetUsec;     // Compute call offset in usec
        bool fFirstCallback;
        ZoneUI fZoneUI;
        
        void computeSlice(int offset, int slice, FAUSTFLOAT** inputs, FAUSTFLOAT** outputs) 
        {
            if (slice > 0) {
                FAUSTFLOAT** inputs_slice = (FAUSTFLOAT**)alloca(fDSP->getNumInputs() * sizeof(FAUSTFLOAT*));
                for (int chan = 0; chan < fDSP->getNumInputs(); chan++) {
                    inputs_slice[chan] = &(inputs[chan][offset]);
                }
                
                FAUSTFLOAT** outputs_slice = (FAUSTFLOAT**)alloca(fDSP->getNumOutputs() * sizeof(FAUSTFLOAT*));
                for (int chan = 0; chan < fDSP->getNumOutputs(); chan++) {
                    outputs_slice[chan] = &(outputs[chan][offset]);
                }
                
                fDSP->compute(slice, inputs_slice, outputs_slice);
            } 
        }
        
        double convertUsecToSample(double usec)
        {
            return std::max(0., (double(getSampleRate()) * (usec - fDateUsec)) / 1000000.);
        }
        
        ztimedmap::iterator getNextControl(DatedControl& res, bool convert_ts)
        {
            DatedControl date1(DBL_MAX, 0);
            ztimedmap::iterator it1, it2 = GUI::gTimedZoneMap.end();
            std::set<FAUSTFLOAT*>::iterator it3;
              
            // Find date of next audio slice to compute
            for (it3 = fZoneUI.fZoneSet.begin(); it3 != fZoneUI.fZoneSet.end(); it3++) {
                // If value list is not empty, get the date and keep the minimal one
                it1 = GUI::gTimedZoneMap.find(*it3);
                if (it1 != GUI::gTimedZoneMap.end()) { // Check if zone still in global GUI::gTimedZoneMap (since MidiUI may have been desallocated)
                    DatedControl date2;
                    if (ringbuffer_peek((*it1).second, (char*)&date2, sizeof(DatedControl)) == sizeof(DatedControl) 
                        && date2.fDate < date1.fDate) {
                        it2 = it1;
                        date1 = date2;
                    }
                }
            }
            
            // If needed, convert date1 in samples from begining of the buffer, possible moving to 0 (if negative)
            if (convert_ts) {
                date1.fDate = convertUsecToSample(date1.fDate);
            }
                
            res = date1;
            return it2;
        }
        
        virtual void computeAux(int count, FAUSTFLOAT** inputs, FAUSTFLOAT** outputs, bool convert_ts)
        {
            int slice, offset = 0;
            ztimedmap::iterator it;
            DatedControl next_control;
             
            // Do audio computation "slice" by "slice"
            while ((it = getNextControl(next_control, convert_ts)) != GUI::gTimedZoneMap.end()) {
                     
                // Compute audio slice
                slice = int(next_control.fDate) - offset;
                computeSlice(offset, slice, inputs, outputs);
                offset += slice;
               
                // Update control
                ringbuffer_t* control_values = (*it).second;
                *((*it).first) = next_control.fValue;
                
                // Move ringbuffer pointer
                ringbuffer_read_advance(control_values, sizeof(DatedControl));
            } 
            
            // Compute last audio slice
            slice = count - offset;
            computeSlice(offset, slice, inputs, outputs);
        }

    public:

        timed_dsp(dsp* dsp):decorator_dsp(dsp), fDateUsec(0),fOffsetUsec(0), fFirstCallback(true)
        {}
        virtual ~timed_dsp() 
        {}
        
        virtual void init(int samplingRate)
        {
            fDSP->init(samplingRate);
        }
        
        virtual void buildUserInterface(UI* ui_interface)   
        { 
            fDSP->buildUserInterface(ui_interface); 
            // Only keep zones that are in GUI::gTimedZoneMap
            fDSP->buildUserInterface(&fZoneUI);
        }
    
        virtual timed_dsp* clone()
        {
            return new timed_dsp(fDSP->clone());
        }
    
        // Default method take a timestamp at 'compute' call time
        virtual void compute(int count, FAUSTFLOAT** inputs, FAUSTFLOAT** outputs)
        {
            compute(::GetCurrentTimeInUsec(), count, inputs, outputs);
        }    
        
        virtual void compute(double date_usec, int count, FAUSTFLOAT** inputs, FAUSTFLOAT** outputs)
        {
            if (date_usec == -1) {
                // JACK mode : timestamp is already in frames
                computeAux(count, inputs, outputs, false);
            } else {
                // Save the timestamp offset in the first callback
                if (fFirstCallback) {
                    fOffsetUsec = ::GetCurrentTimeInUsec() - date_usec;
                    fDateUsec = date_usec + fOffsetUsec;
                    fFirstCallback = false;
                }
                
                // RtMidi mode : timestamp must be converted in frames
                computeAux(count, inputs, outputs, true);
                
                // Keep call date 
                fDateUsec = date_usec + fOffsetUsec;
            }
        }
        
};

#endif
