from machine import Pin, I2C, ADC
import time
from ssd1306 import SSD1306_I2C

# ── Composants ──────────────────────────────────────────
led = Pin(13, Pin.OUT)          # LED indicateur (GP13)
bouton = Pin(3, Pin.IN, Pin.PULL_UP)

i2c = I2C(0, scl=Pin(1), sda=Pin(0))
oled = SSD1306_I2C(128, 64, i2c)

pot = ADC(27)

# ── État du chronomètre ──────────────────────────────────
running = False          # en cours / arrêté
start_ms = 0             # ticks_ms au dernier démarrage
elapsed_ms = 0           # millisecondes accumulées

was_pressed = False      # anti-rebond bouton
was_max = False          # anti-rebond potentiomètre (réinit.)

# ── Fonctions utilitaires ────────────────────────────────
def format_time(ms):
    """Retourne (mm, ss, cs) depuis ms."""
    total_s = ms // 1000
    minutes = total_s // 60
    seconds = total_s % 60
    centisec = (ms % 1000) // 10
    return minutes, seconds, centisec

def display(minutes, seconds, centisec, running, reset_msg=False):
    oled.fill(0)
    oled.text("Chronometre", 10, 0)
    oled.text("-" * 16, 0, 10)

    time_str = "{:02d}:{:02d}.{:02d}".format(minutes, seconds, centisec)
    oled.text(time_str, 24, 28)

    if reset_msg:
        oled.text("REINITIALISE", 8, 50)
    else:
        status = "En cours..." if running else "Arrete"
        oled.text(status, 0, 50)

    oled.show()

# ── Boucle principale ────────────────────────────────────
while True:
    now = time.ticks_ms()

    # 1. Lecture bouton (bascule démarrage/arrêt)
    pressed = bouton.value() == 0
    if pressed and not was_pressed:
        if running:
            # Arrêt : on fige le temps accumulé
            elapsed_ms += time.ticks_diff(now, start_ms)
            running = False
        else:
            # Démarrage
            start_ms = now
            running = True
    was_pressed = pressed

    # 2. Lecture potentiomètre (réinitialisation si max)
    pot_val = pot.read_u16()
    reset_msg = False
    if pot_val >= 65000 and not was_max:
        elapsed_ms = 0
        running = False
        start_ms = 0
        was_max = True
        reset_msg = True
    elif pot_val < 65000:
        was_max = False

    # 3. Calcul du temps courant
    if running:
        current_ms = elapsed_ms + time.ticks_diff(now, start_ms)
    else:
        current_ms = elapsed_ms

    # 4. LED : allumée si running
    led.value(1 if running else 0)

    # 5. Affichage OLED
    m, s, cs = format_time(current_ms)
    display(m, s, cs, running, reset_msg)

    time.sleep_ms(30)