/************************** BEGIN audio.h **************************/
/************************************************************************
 FAUST Architecture File
 Copyright (C) 2003-2017 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 __audio__
#define __audio__

#include <set>
#include <utility>

class dsp;

typedef void (* shutdown_callback)(const char* message, void* arg);

typedef void (* compute_callback)(void* arg);

class audio {
    
    protected:
    
        shutdown_callback fShutdown;    // Shutdown callback
        void* fShutdownArg;             // Shutdown callback data
    
        std::set<std::pair<compute_callback, void*> > fComputeCallbackList;
    
    public:
    
        audio():fShutdown(nullptr), fShutdownArg(nullptr) {}
        virtual ~audio() {}

        /**
         * Init the DSP.
         * @param name - the DSP name to be given to the audio driven
         * (could appear as a JACK client for instance)
         * @param dsp - the dsp that will be initialized with the driver sample rate
         *
         * @return true is sucessful, false in case of driver failure.
         **/
        virtual bool init(const char* name, dsp* dsp) = 0;
    
        /**
         * Start audio processing.
         * @return true is sucessful, false if case of driver failure.
         **/
        virtual bool start() = 0;
    
        /**
         * Stop audio processing.
         **/
        virtual void stop() = 0;
    
        void setShutdownCallback(shutdown_callback cb, void* arg)
        {
            fShutdown = cb;
            fShutdownArg = arg;
        }
    
        void addControlCallback(compute_callback cb, void* arg)
        {
            fComputeCallbackList.insert(std::make_pair(cb, arg));
        }
    
        bool removeControlCallback(compute_callback cb, void* arg)
        {
            return (fComputeCallbackList.erase(std::make_pair(cb, arg)) == 1);
        }
    
        void runControlCallbacks()
        {
            for (const auto& it : fComputeCallbackList) {
                it.first(it.second);
            }
        }
    
        // Return buffer size in frames.
        virtual int getBufferSize() = 0;
    
        // Return the driver sample rate in Hz.
        virtual int getSampleRate() = 0;

        // Return the driver hardware inputs number.
        virtual int getNumInputs() = 0;
    
        // Return the driver hardware outputs number.
        virtual int getNumOutputs() = 0;
    
        /**
         * @return Returns the average proportion of available CPU
         * being spent inside the audio callbacks (between 0.0 and 1.0).
         **/
        virtual float getCPULoad() { return 0.f; }
};
					
#endif
/**************************  END  audio.h **************************/
