#pragma once

#include <math.h>

typedef struct {

// Bus compressor state

float envelope_L;

float envelope_R;

float gain_reduction;

float attack_coeff;

float release_coeff;

int sample_rate;

} BusCompressor;

typedef struct {

float osc_gain[4];

float master;

float master_pan; // Stereo panning for master (-1.0 left to +1.0 right, 0.0 center)

float master_width; // Stereo width for master (0.0 mono to 2.0 max)

// Bus compressor

BusCompressor compressor;

// Compressor parameters

float comp_threshold; // dB

float comp_ratio; // ratio (1:1 to 20:1)

float comp_attack; // seconds

float comp_release; // seconds

float comp_makeup_gain; // dB

int comp_enabled;

// Mastering parameters

int dc_filter_enabled; // DC offset filter enabled

float dc_filter_freq; // DC filter cutoff frequency (Hz)

int soft_clip_enabled; // Soft clipping enabled

float soft_clip_threshold; // Soft clipping threshold (dB)

float soft_clip_ratio; // Soft clipping ratio (knee softness)

int auto_gain_enabled; // Auto gain control enabled

float auto_gain_target; // Target level for auto gain (dB)

float peak_level; // Current peak level (for display)

float rms_level; // Current RMS level (for display)

// Auto gain mastering state

float auto_gain_gain;

float gain_smoothing_coeff;

float dc_filter_state_L;

float dc_filter_state_R;

} Mixer;

void mixer_init(Mixer *mixer);

void mixer_apply(Mixer *mixer, float *stereo, int frames);

void mixer_set_param(Mixer *mixer, const char *param, float value);

void mixer_set_sample_rate(Mixer *mixer, int sample_rate);

// Mastering functions

float dc_filter_process(float input, float *state, float cutoff_freq, float sample_rate);

float soft_clip_process(float input, float threshold_db, float ratio);

void update_level_meters(float *stereo, int frames, float *peak_level, float *rms_level);

// Utility functions

float db_to_linear(float db);

float linear_to_db(float linear);