#pragma once
// Pure state machine: no ESP-IDF dependencies, can be compiled and tested on a PC.
#include <stdbool.h>
#include <stdint.h>

typedef enum { DET_IDLE = 0, DET_TRIGGERED, DET_COOLDOWN } det_state_t;

typedef struct {
    uint32_t win_n;         // window length in frames (clamped to 1..32)
    uint32_t win_m;         // matches required (clamped to 1..win_n)
    uint32_t cooldown_ms;
} detector_cfg_t;

typedef struct {
    det_state_t state;
    uint32_t hist;          // bit 0 = newest frame, 1 = matched
    uint32_t cooldown_start_ms;
    uint32_t triggers;
} detector_t;

void detector_init(detector_t *d);
void detector_reset(detector_t *d);     // back to IDLE with empty history

// Loudness gate AND score >= threshold.
bool detector_is_match(float rms, float score, float min_rms, float threshold);

// Feed one frame. Returns true exactly once per trigger (IDLE -> TRIGGERED).
// TRIGGERED lasts one frame, then COOLDOWN until cooldown_ms elapsed, then IDLE
// with a cleared history (the buzzer's tail cannot re-trigger).
bool detector_update(detector_t *d, bool match, uint32_t now_ms, const detector_cfg_t *cfg);
const char *detector_state_name(det_state_t s);