from machine import Pin
import time

btn_start = Pin(18,Pin.IN,Pin.PULL_DOWN)
btn_stop = Pin(19,Pin.IN,Pin.PULL_DOWN)
btn_reset = Pin(20,Pin.IN,Pin.PULL_DOWN)
sw_fault = Pin(21,Pin.IN,Pin.PULL_DOWN)

STATE_STOPPED = 0
STATE_RUNNING = 1
STATE_FAULT = 2

current_state = STATE_STOPPED



motor_relay = Pin(16,Pin.OUT)

print("System Ready : Press START to run.")

while True:
    if sw_fault.value() == 1:
        current_state = STATE_FAULT

    if current_state == STATE_FAULT:
        motor_relay.value(0)
        print("Fault Detected : Motor Locked")

        if sw_fault.value() == 0 and btn_reset() == 1:
            current_state = STATE_STOPPED
            print("System Reset : Ready to Start")
            time.sleep(0.5)

    elif current_state == STATE_STOPPED:
        motor_relay.value(0)
        if btn_start.value() == 1:
            current_state = STATE_RUNNING
            print("Motor Started (State : Running)")
            time.sleep(0.3)

    elif current_state == STATE_RUNNING:
        motor_relay.value(1)
        if btn_stop.value() == 1:
            current_state = STATE_STOPPED
            print("Motor Stopped (State : Stopped)")
            time.sleep(0.3)
    time.sleep(0.1)