# MicroPython - Wokwi CrossFit Buzzer (single line) simulator
# Hardware (Wokwi diagram.json matches these pins):
# - TM1637 4-digit display: CLK=GPIO18, DIO=GPIO19
# - BUZZ button (athlete): GPIO15 to GND (internal PULL_UP)
# - GO button (master sim): GPIO5 to GND (internal PULL_UP)
# - LED (status): GPIO4
# - Piezo buzzer: GPIO2 (active-high)
#
# Usage on Wokwi:
# - Click the "GO" button to start the local chronometer.
# - Click the "BUZZ" button to freeze the time (simulates athlete finishing).
# - Press GO again to re-arm (RESET) when in BUZZED state.
#
# States: IDLE -> RUNNING -> BUZZED
# - IDLE   : display 00:00, waiting for GO
# - RUNNING: chronometer running
# - BUZZED : display frozen until GO (reset) is pressed

import time
from machine import Pin
import tm1637

# Pins
PIN_CLK = 18
PIN_DIO = 19
PIN_BUZZ_BTN = 15
PIN_GO_BTN = 5
PIN_LED = 4
PIN_PIEZO = 2

# Display init
tm = tm1637.TM1637(clk=Pin(PIN_CLK), dio=Pin(PIN_DIO))
tm.brightness(7)
tm.show('0000')
tm.show_doublepoint(False)

# IO init
btn_buzz = Pin(PIN_BUZZ_BTN, Pin.IN, Pin.PULL_UP)
btn_go = Pin(PIN_GO_BTN, Pin.IN, Pin.PULL_UP)
led = Pin(PIN_LED, Pin.OUT)
piezo = Pin(PIN_PIEZO, Pin.OUT)

# Helpers
def beep(n=1, dur=60, gap=60):
    for _ in range(n):
        piezo.on(); time.sleep_ms(dur)
        piezo.off(); time.sleep_ms(gap)

def mmss_from_ms(ms):
    if ms < 0:
        ms = 0
    total_sec = ms // 1000
    m = total_sec // 60
    s = total_sec % 60
    m = m % 100  # clamp to 99:59 for 4-digit display
    return (m, s)

def show_mmss(m, s, running=False):
    # e.g. m=1,s=23 -> "0123" with blinking colon if running
    digits = f"{m:02d}{s:02d}"
    tm.show(digits)
    tm.show_doublepoint(running)

# Debounce
last_buzz = 1
last_go = 1
db_ms = 120
last_buzz_ts = 0
last_go_ts = 0

# State
state = "IDLE"
t0 = 0
frozen_ms = 0

def reset_to_idle():
    global state, frozen_ms
    state = "IDLE"
    frozen_ms = 0
    led.on()
    show_mmss(0, 0, running=False)

reset_to_idle()

def handle_buttons():
    global last_buzz, last_go, last_buzz_ts, last_go_ts
    now = time.ticks_ms()
    v_buzz = btn_buzz.value()
    v_go = btn_go.value()

    buzz_pressed = (v_buzz == 0 and last_buzz == 1 and time.ticks_diff(now, last_buzz_ts) > db_ms)
    go_pressed = (v_go == 0 and last_go == 1 and time.ticks_diff(now, last_go_ts) > db_ms)

    if buzz_pressed:
        last_buzz_ts = now
    if go_pressed:
        last_go_ts = now

    last_buzz = v_buzz
    last_go = v_go
    return buzz_pressed, go_pressed

def loop():
    global state, t0, frozen_ms
    while True:
        buzz_pressed, go_pressed = handle_buttons()

        if state == "IDLE":
            if go_pressed:
                # GO: start running
                t0 = time.ticks_ms()
                state = "RUNNING"
                led.off()
                beep(1, 100, 50)

        elif state == "RUNNING":
            # Update display
            elapsed = time.ticks_diff(time.ticks_ms(), t0)
            m, s = mmss_from_ms(elapsed)
            show_mmss(m, s, running=True)

            if buzz_pressed:
                # Freeze
                frozen_ms = elapsed
                m, s = mmss_from_ms(frozen_ms)
                show_mmss(m, s, running=False)
                state = "BUZZED"
                beep(2, 60, 40)

        elif state == "BUZZED":
            # Wait for GO as RESET to go back to IDLE
            if go_pressed:
                reset_to_idle()
                beep(1, 50, 50)

        time.sleep_ms(10)

loop()