#ifndef AUDIO_EFFECT_SPECTRUM_ANALYZER_H
#define AUDIO_EFFECT_SPECTRUM_ANALYZER_H

#include "servers/audio/audio_effect.h"

class AudioEffectSpectrumAnalyzer;

class AudioEffectSpectrumAnalyzerInstance : public AudioEffectInstance {
	GDCLASS(AudioEffectSpectrumAnalyzerInstance, AudioEffectInstance)

public:
	enum MagnitudeMode {
		MAGNITUDE_AVERAGE,
		MAGNITUDE_MAX,
	};

private:
	friend class AudioEffectSpectrumAnalyzer;
	Ref<AudioEffectSpectrumAnalyzer> base;

	Vector<Vector<AudioFrame> > fft_history;
	Vector<float> temporal_fft;
	int temporal_fft_pos;
	int fft_size;
	int fft_count;
	int fft_pos;
	float mix_rate;
	uint64_t last_fft_time;

protected:
	static void _bind_methods();

public:
	virtual void process(const AudioFrame *p_src_frames, AudioFrame *p_dst_frames, int p_frame_count);
	Vector2 get_magnitude_for_frequency_range(float p_begin, float p_end, MagnitudeMode p_mode = MAGNITUDE_MAX) const;
};

VARIANT_ENUM_CAST(AudioEffectSpectrumAnalyzerInstance::MagnitudeMode)

class AudioEffectSpectrumAnalyzer : public AudioEffect {
	GDCLASS(AudioEffectSpectrumAnalyzer, AudioEffect)
public:
	enum FFT_Size {
		FFT_SIZE_256,
		FFT_SIZE_512,
		FFT_SIZE_1024,
		FFT_SIZE_2048,
		FFT_SIZE_4096,
		FFT_SIZE_MAX
	};

public:
	friend class AudioEffectSpectrumAnalyzerInstance;
	float buffer_length;
	float tapback_pos;
	FFT_Size fft_size;

protected:
	static void _bind_methods();

public:
	Ref<AudioEffectInstance> instance();
	void set_buffer_length(float p_seconds);
	float get_buffer_length() const;
	void set_tap_back_pos(float p_seconds);
	float get_tap_back_pos() const;

	void set_fft_size(FFT_Size);
	FFT_Size get_fft_size() const;

	AudioEffectSpectrumAnalyzer();
};

VARIANT_ENUM_CAST(AudioEffectSpectrumAnalyzer::FFT_Size);

#endif // AUDIO_EFFECT_SPECTRUM_ANALYZER_H