#ifndef BOO_AUDIOVOICEENGINE_HPP
#define BOO_AUDIOVOICEENGINE_HPP

#include "boo/audiodev/IAudioVoiceEngine.hpp"
#include "LtRtProcessing.hpp"
#include "Common.hpp"
#include "AudioVoice.hpp"
#include "AudioSubmix.hpp"
#include <functional>
#include <mutex>

namespace boo
{

/** Base class for managing mixing and sample-rate-conversion amongst active voices */
class BaseAudioVoiceEngine : public IAudioVoiceEngine
{
protected:
    friend class AudioVoice;
    friend class AudioSubmix;
    friend class AudioVoiceMono;
    friend class AudioVoiceStereo;
    float m_totalVol = 1.f;
    AudioVoiceEngineMixInfo m_mixInfo;
    std::recursive_mutex m_dataMutex;
    AudioVoice* m_voiceHead = nullptr;
    AudioSubmix* m_submixHead = nullptr;
    size_t m_5msFrames = 0;
    IAudioVoiceEngineCallback* m_engineCallback = nullptr;

    /* Shared scratch buffers for accumulating audio data for resampling */
    std::vector<int16_t> m_scratchIn;
    std::vector<int16_t> m_scratch16Pre;
    std::vector<int32_t> m_scratch32Pre;
    std::vector<float> m_scratchFltPre;
    template <typename T> std::vector<T>& _getScratchPre();
    std::vector<int16_t> m_scratch16Post;
    std::vector<int32_t> m_scratch32Post;
    std::vector<float> m_scratchFltPost;
    template <typename T> std::vector<T>& _getScratchPost();

    /* LtRt processing if enabled */
    std::unique_ptr<LtRtProcessing> m_ltRtProcessing;
    std::vector<int16_t> m_ltRtIn16;
    std::vector<int32_t> m_ltRtIn32;
    std::vector<float> m_ltRtInFlt;
    template <typename T> std::vector<T>& _getLtRtIn();

    std::unique_ptr<AudioSubmix> m_mainSubmix;
    std::list<AudioSubmix*> m_linearizedSubmixes;
    bool m_submixesDirty = true;

    template <typename T>
    void _pumpAndMixVoices(size_t frames, T* dataOut);

public:
    BaseAudioVoiceEngine() : m_mainSubmix(std::make_unique<AudioSubmix>(*this, nullptr, -1, false)) {}
    ~BaseAudioVoiceEngine();
    ObjToken<IAudioVoice> allocateNewMonoVoice(double sampleRate,
                                               IAudioVoiceCallback* cb,
                                               bool dynamicPitch=false);

    ObjToken<IAudioVoice> allocateNewStereoVoice(double sampleRate,
                                                 IAudioVoiceCallback* cb,
                                                 bool dynamicPitch=false);

    ObjToken<IAudioSubmix> allocateNewSubmix(bool mainOut, IAudioSubmixCallback* cb, int busId);

    void setCallbackInterface(IAudioVoiceEngineCallback* cb);

    void setVolume(float vol);
    bool enableLtRt(bool enable);
    const AudioVoiceEngineMixInfo& mixInfo() const;
    const AudioVoiceEngineMixInfo& clientMixInfo() const;
    AudioChannelSet getAvailableSet() {return clientMixInfo().m_channels;}
    void pumpAndMixVoices() {}
    size_t get5MsFrames() const {return m_5msFrames;}
};

template <> inline std::vector<int16_t>& BaseAudioVoiceEngine::_getScratchPre<int16_t>() { return m_scratch16Pre; }
template <> inline std::vector<int32_t>& BaseAudioVoiceEngine::_getScratchPre<int32_t>() { return m_scratch32Pre; }
template <> inline std::vector<float>& BaseAudioVoiceEngine::_getScratchPre<float>() { return m_scratchFltPre; }

template <> inline std::vector<int16_t>& BaseAudioVoiceEngine::_getScratchPost<int16_t>() { return m_scratch16Post; }
template <> inline std::vector<int32_t>& BaseAudioVoiceEngine::_getScratchPost<int32_t>() { return m_scratch32Post; }
template <> inline std::vector<float>& BaseAudioVoiceEngine::_getScratchPost<float>() { return m_scratchFltPost; }

template <> inline std::vector<int16_t>& BaseAudioVoiceEngine::_getLtRtIn<int16_t>() { return m_ltRtIn16; }
template <> inline std::vector<int32_t>& BaseAudioVoiceEngine::_getLtRtIn<int32_t>() { return m_ltRtIn32; }
template <> inline std::vector<float>& BaseAudioVoiceEngine::_getLtRtIn<float>() { return m_ltRtInFlt; }

}

#endif // BOO_AUDIOVOICEENGINE_HPP