import machine
import utime

# LED related
led_onboard = machine.Pin(25, machine.Pin.OUT)
led_0 = machine.Pin(0, machine.Pin.OUT)
led_1 = machine.Pin(1, machine.Pin.OUT)
led_2 = machine.Pin(2, machine.Pin.OUT)
led_3 = machine.Pin(3, machine.Pin.OUT)
led_4 = machine.Pin(4, machine.Pin.OUT)
led_5 = machine.Pin(5, machine.Pin.OUT)
led_6 = machine.Pin(6, machine.Pin.OUT)
led_7 = machine.Pin(7, machine.Pin.OUT)
LEDS = (led_0, led_1, led_2, led_3, led_4, led_5, led_6, led_7)

LED_mask = 0
LED_state = 0
top_to_down = True
move_LEDS = False

# button related
big_blue_button = machine.Pin(8, machine.Pin.IN, machine.Pin.PULL_UP)
big_red_button = machine.Pin(9, machine.Pin.IN, machine.Pin.PULL_UP)

button_state = 0
button_pressed_released = False
last_time = 0 # the last time the button is pressed
debounce_time = 30 #ms

# FSM related
FSM_state = 0

# callback functions for the timers
def sense_ISR(timer):
    check_button()

def compute_ISR(timer):
    FSM()

def actuate_ISR(time):
    led_move_one_step()
    move_lights()

# define the timers
timer_sense = machine.Timer()
timer_compute = machine.Timer()
timer_actuate = machine.Timer()

# freq in Hz, period in ms, mode= PERIODIC, ONE_SHOT, callback --> tic(timer)
timer_sense.init(period = 50, mode = machine.Timer.PERIODIC, callback = sense_ISR)
timer_compute.init(period = 100, mode = machine.Timer.PERIODIC, callback = compute_ISR)
timer_actuate.init(period = 300, mode = machine.Timer.PERIODIC, callback = actuate_ISR)

# function definitions
def check_button():
  global button_state, button_pressed_released, last_time
  if button_state == 0:
    if big_blue_button.value() == 0:
      new_time = utime.ticks_ms()
      if (new_time - last_time > debounce_time):
        last_time = new_time
        button_state = 1
  elif button_state == 1:
    if big_blue_button.value() == 1:
      new_time = utime.ticks_ms()
      if (new_time - last_time > debounce_time):
        last_time = new_time
        button_state = 0
        button_pressed_released = True

def FSM():
  global FSM_state, move_LEDS, button_pressed_released
  if FSM_state == 0:
    FSM_state = 1
    initialize_game()
  elif FSM_state == 1:
    if button_pressed_released:
      FSM_state = 2
      move_LEDS = True
      button_pressed_released = False
  elif FSM_state == 2:
    if button_pressed_released:
      FSM_state = 3
      move_LEDS = False
      button_pressed_released = False
  else: # FSM_state = 3
    if button_pressed_released:
      FSM_state = 0
      button_pressed_released = False

def initialize_game():
  global LED_state, LED_mask, top_to_down
  LED_state = 0
  LED_mask = 0
  top_to_down = True

def led_move_one_step():
  global LED_mask, top_to_down, move_LEDS
  if move_LEDS:
    if top_to_down:
      if LED_mask == 0:
        LED_mask = 0b10000000
        return
      if LED_mask != 0b00000001:
          LED_mask = LED_mask >> 1
      else:
          LED_mask = LED_mask << 1
          top_to_down = False
    else:
      if LED_mask != 0b10000000:
          LED_mask = LED_mask << 1
      else:
          LED_mask = LED_mask >> 1
          top_to_down = True

def move_lights():
  global LED_state
  LED_state = LED_mask

  LED_bit = 7
  for led in LEDS:
      led.value((LED_state >> LED_bit) & 1)
      LED_bit = LED_bit - 1

def clear_leds():
  LED_mask = 0
  move_lights()

# Main Loop
while big_red_button.value():
  pass

clear_leds()
timer_sense.deinit()
timer_actuate.deinit()
timer_compute.deinit()