$#include "Audio.h"

/// %Audio subsystem.
class Audio : public Object
{
public:
    /// Initialize sound output with specified buffer length and output mode.
    bool SetMode(int bufferLengthMSec, int mixRate, bool stereo, bool interpolation = true);
    /// Run update on sound sources. Not required for continued playback, but frees unused sound sources & sounds and updates 3D positions.
    void Update(float timeStep);
    /// Restart sound output.
    bool Play();
    /// Suspend sound output.
    void Stop();
    /// Set master gain on a specific sound type such as sound effects, music or voice.
    void SetMasterGain(SoundType type, float gain);
    /// Set active sound listener for 3D sounds.
    void SetListener(SoundListener* listener);
    /// Stop any sound source playing a certain sound clip.
    void StopSound(Sound* sound);

    /// Return byte size of one sample.
    unsigned GetSampleSize() const { return sampleSize_; }
    /// Return mixing rate.
    int GetMixRate() const { return mixRate_; }
    /// Return whether output is interpolated.
    bool GetInterpolation() const { return interpolation_; }
    /// Return whether output is stereo.
    bool IsStereo() const { return stereo_; }
    /// Return whether audio is being output.
    bool IsPlaying() const { return playing_; }
    /// Return whether an audio stream has been reserved.
    bool IsInitialized() const { return deviceID_ != 0; }
    /// Return master gain for a specific sound source type.
    float GetMasterGain(SoundType type) const;
    /// Return active sound listener.
    SoundListener* GetListener() const;
    
    /// Add a sound source to keep track of. Called by SoundSource.
    void AddSoundSource(SoundSource* soundSource);
    /// Remove a sound source. Called by SoundSource.
    void RemoveSoundSource(SoundSource* soundSource);
    
    /// Return sound type specific gain multiplied by master gain.
    float GetSoundSourceMasterGain(SoundType type) const { return masterGain_[SOUND_MASTER] * masterGain_[type]; }
};