from machine import Pin, time_pulse_us
import time
import ujson


IR_PIN = 13
TRIG_PIN = 5
ECHO_PIN = 18
LED_PASSAGE_PIN = 2
LED_STOCK_OK_PIN = 15
LED_STOCK_LOW_PIN = 4

HAUTEUR_BAC_CM = 35.0
SEUIL_STOCK_FAIBLE_CM = 25.0

STOCK_INTERVAL_MS = 1000
IR_MIN_INTERVAL_MS = 800
LED_PASSAGE_DURATION_MS = 150

ir_sensor = Pin(IR_PIN, Pin.IN, Pin.PULL_UP)
trig = Pin(TRIG_PIN, Pin.OUT)
echo = Pin(ECHO_PIN, Pin.IN)
led_passage = Pin(LED_PASSAGE_PIN, Pin.OUT)
led_stock_ok = Pin(LED_STOCK_OK_PIN, Pin.OUT)
led_stock_low = Pin(LED_STOCK_LOW_PIN, Pin.OUT)

last_ir_state = 1
last_ir_event_ms = time.ticks_ms() - IR_MIN_INTERVAL_MS
last_passage_led_ms = 0
last_stock_measure_ms = time.ticks_ms() - STOCK_INTERVAL_MS
last_stock_state = None
passage_count = 0


def clamp(value, low, high):
    return max(low, min(high, value))


def read_distance_cm():
    trig.value(0)
    time.sleep_us(2)
    trig.value(1)
    time.sleep_us(10)
    trig.value(0)

    try:
        duration_us = time_pulse_us(echo, 1, 30000)
    except OSError:
        return None

    if duration_us <= 0:
        return None

    return duration_us * 0.0343 / 2.0


def print_json(payload):
    print(ujson.dumps(payload))


def handle_ir(now_ms):
    global last_ir_state, last_ir_event_ms, last_passage_led_ms, passage_count

    ir_state = ir_sensor.value()
    ir_detected = ir_state == 0

    if (
        ir_detected
        and last_ir_state == 1
        and time.ticks_diff(now_ms, last_ir_event_ms) >= IR_MIN_INTERVAL_MS
    ):
        last_ir_event_ms = now_ms
        last_passage_led_ms = now_ms
        passage_count += 1
        led_passage.value(1)

        print_json({
            "type": "ir_passage",
            "capteur_id": "IR_P1",
            "poste": "P1",
            "node_id": "WOKWI_PICO_IR_US",
            "ir": 1,
            "piece_increment": 1,
            "passage_count": passage_count,
        })

    last_ir_state = ir_state

    if led_passage.value() and time.ticks_diff(now_ms, last_passage_led_ms) >= LED_PASSAGE_DURATION_MS:
        led_passage.value(0)


def handle_stock(now_ms):
    global last_stock_measure_ms, last_stock_state

    if time.ticks_diff(now_ms, last_stock_measure_ms) < STOCK_INTERVAL_MS:
        return

    last_stock_measure_ms = now_ms
    distance_cm = read_distance_cm()

    if distance_cm is None:
        print_json({
            "type": "stock_ultrason_error",
            "capteur_id": "US_P1",
            "poste": "P1",
            "node_id": "WOKWI_PICO_IR_US",
            "etat": "ERREUR_MESURE",
        })
        return

    distance_cm = round(distance_cm, 1)
    distance_limited = clamp(distance_cm, 0.0, HAUTEUR_BAC_CM)
    niveau_estime_percent = round(100.0 * (1.0 - distance_limited / HAUTEUR_BAC_CM), 1)
    stock_faible = distance_cm >= SEUIL_STOCK_FAIBLE_CM
    etat_stock = "FAIBLE" if stock_faible else "OK"

    led_stock_ok.value(0 if stock_faible else 1)
    led_stock_low.value(1 if stock_faible else 0)

    payload = {
        "type": "stock_ultrason",
        "capteur_id": "US_P1",
        "poste": "P1",
        "node_id": "WOKWI_PICO_IR_US",
        "distance_cm": distance_cm,
        "niveau_estime_percent": niveau_estime_percent,
        "stock_faible": stock_faible,
        "etat_stock": etat_stock,
        "seuil_stock_faible_cm": SEUIL_STOCK_FAIBLE_CM,
        "hauteur_bac_cm": HAUTEUR_BAC_CM,
    }
    print_json(payload)

    if last_stock_state is not None and last_stock_state != etat_stock:
        alert_payload = dict(payload)
        alert_payload["type"] = "stock_alert"
        alert_payload["alerte"] = "STOCK_FAIBLE" if stock_faible else "STOCK_OK"
        print_json(alert_payload)

    last_stock_state = etat_stock


print("Simulation Wokwi Raspberry Pi Pico prete: IR + ultrason.")
print("Bouton IR: appui = passage piece. HC-SR04: distance_cm mesuree, stock estime par calcul.")

while True:
    now = time.ticks_ms()
    handle_ir(now)
    handle_stock(now)
    time.sleep_ms(10)