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#ifndef CORE_AUDIO_H
#define CORE_AUDIO_H

/*
 * Sound out (SDL3). Everything is made up on the fly - noise, tones, filters,
 * envelopes - no sound files. Short voices (a step, a chop, a clink) play
 * once; steady beds (wind, rain, a fire, ...) run all the time and are only
 * turned up and down. The game sets what plays; the audio thread mixes it.
 * Without a sound device everything here quietly does nothing.
 */

#include <stdbool.h>

typedef enum {
    WAVE_NOISE,   /* white noise (shaped by the filters) */
    WAVE_SINE,    /* a tone, gliding from freq to freq_end */
    WAVE_SAW,     /* a buzzing tone */
    WAVE_CRACKLE  /* sparse clicks (gravel, glass, twigs): freq = clicks a second */
} Wave;

typedef struct {
    Wave  wave;
    float freq, freq_end; /* Hz (freq_end 0: stays at freq) */
    float low, high;      /* filters: lowpass and highpass cutoff (Hz, 0: none) */
    float attack, decay;  /* s: up in attack, then dying away (decay: down to a third) */
    float length;         /* s: cut off after this (0: when it's died away) */
    float gain;           /* 0..1 */
    float pan;            /* -1 left .. +1 right */
    float delay;          /* s before it starts */
} Voice;

typedef enum {
    BED_WIND,     /* param: 0..1 how strong (brighter, gustier) */
    BED_RAIN,     /* param: 0 out in it .. 1 heard through a tent (dull, drumming) */
    BED_FIRE,     /* param: 0..1 how big */
    BED_SAW,      /* param: 0 idling .. 1 cutting (a chainsaw) */
    BED_ENGINE,   /* param: 0..1 how fast (the car) */
    BED_CRICKETS, /* param: unused */
    BED_HOSE,     /* param: unused */
    BED_FLOOR,    /* a floor's music (BED_FLOOR + 0..3: rock, psytrance, hand drums, techno); param: 0 near .. 1 far off (muffled) */
    BED_COUNT = BED_FLOOR + 4
} Bed;

/* Opens the sound device (false: none - the game goes on silent). */
bool Audio_init(void);
void Audio_shutdown(void);
/* One short sound. */
void Audio_play(const Voice *voice);
/* A bed this loud (0: off), from this side, its param (eased over a moment). */
void Audio_bed(Bed bed, float gain, float pan, float param);
/* All quiet (M), or not; and everything paused (menus: the beds go quiet). */
void Audio_mute(bool mute);
bool Audio_muted(void);
void Audio_pause(bool paused);

#endif /* CORE_AUDIO_H */