# DieHard 3 
# Collect exactly 4 liters

import time
from machine import Pin

# --------------------------------------------------------------------------
# Functions
# --------------------------------------------------------------------------
# Fill entirely
def fillBoard(diodes):
  for d in diodes:
    d.value(1)
  if len(diodes) == 5:
    status = [1,1,1,1,1]
  if len(diodes) == 3:
    status = [1,1,1]
  return status

# Empty entirely
def emptyBoard(diodes):
  for d in diodes:
    d.value(0)
  if len(diodes) == 5:
    status = [0,0,0,0,0]
  if len(diodes) == 3:
    status = [0,0,0]
  return status

# Update specific state
def updateDiodes(diodes, status):
  for i in range(len(diodes)):
    diodes[i].value(status[i])

# Transfer from one side to the other
def transferContent(diodesSrc, diodesDst):
  global status5, status3
  # Identify source & destination
  if len(diodesSrc) == 5:
    statusSrc = status5
    statusDst = status3
  else:
    statusSrc = status3
    statusDst = status5
  # Identify available pools
  availableToSend = sum(statusSrc)
  availableToReceive = len(statusDst)-sum(statusDst)
  # Transfer content theoretically
  while (availableToSend > 0) and (availableToReceive > 0):
    statusDst = statusDst[1:] + [1]
    statusSrc = [0] + statusSrc[:-1]
    availableToSend -= 1
    availableToReceive -= 1
  # Transfer content practically
  updateDiodes(diodesSrc, statusSrc)
  updateDiodes(diodesDst, statusDst)
  # Memorize new states
  if len(diodesSrc) == 5:
    status5 = statusSrc
    status3 = statusDst
  else:
    status3 = statusSrc
    status5 = statusDst


# --------------------------------------------------------------------------
# Correct solution
# --------------------------------------------------------------------------
S = [0,1,1,1,1]  

# --------------------------------------------------------------------------
# Items description
# --------------------------------------------------------------------------
# LED boards
D5 = [Pin(6, Pin.OUT), Pin(5, Pin.OUT), Pin(4, Pin.OUT), Pin(3, Pin.OUT), Pin(2, Pin.OUT)]
status5 = [0,0,0,0,0] # idx 0 is top level
D3 = [Pin(19, Pin.OUT), Pin(20, Pin.OUT), Pin(21, Pin.OUT)]
status3 = [0,0,0] # idx 0 is top level

# Pushbuttons
push_button_left_fill = Pin(28, Pin.IN, Pin.PULL_DOWN)
push_button_left_empty = Pin(27, Pin.IN, Pin.PULL_DOWN)
push_button_transfer_left = Pin(22, Pin.IN, Pin.PULL_DOWN)
push_button_transfer_right = Pin(26, Pin.IN, Pin.PULL_DOWN)
push_button_right_fill = Pin(17, Pin.IN, Pin.PULL_DOWN)
push_button_right_empty = Pin(16, Pin.IN, Pin.PULL_DOWN)

# Check status diodes
diode_OK = Pin(15, Pin.OUT)
diode_KO = Pin(12, Pin.OUT)

# --------------------------------------------------------------------------
# Main loop
# --------------------------------------------------------------------------
while True:
  # Callbacks
  if push_button_left_fill.value():
    status5 = fillBoard(D5)
  if push_button_left_empty.value():
    status5 = emptyBoard(D5)
  if push_button_right_fill.value():
    status3 = fillBoard(D3)
  if push_button_right_empty.value():
    status3 = emptyBoard(D3)
  if push_button_transfer_left.value():
    transferContent(D3, D5)
  if push_button_transfer_right.value():
    transferContent(D5, D3)
  # Check result
  if status5 == S:
    diode_OK.value(1)
    diode_KO.value(0)
    break
  else:
    diode_OK.value(0)
    diode_KO.value(1)

# --------------------------------------------------------------------------
# Finish puzzle
# --------------------------------------------------------------------------
print('***Congrats on solving the puzzle!***')