from machine import Pin, I2C
from neopixel import NeoPixel
from time import sleep
from random import randint
from pico_i2c_lcd import I2cLcd

i2c = I2C(0, sda=Pin(20), scl=Pin(21), freq=100000)
I2C_ADDR = i2c.scan()[0]
lcd = I2cLcd(i2c, I2C_ADDR, 2, 16)

score = 0

def pressUp(event):
    global dir
    dir = 'n'

def pressDown(event):
    global dir
    dir = 's'

def pressLeft(event):
    global dir
    dir = 'w'

def pressRight(event):
    global dir
    dir = 'e'

def c(x, y):
    return 8*y + x

def newApple():
    global apX, apY
    while posInSnake(apX, apY):
        apX = randint(0, 7)
        apY = randint(0, 7)
    np[c(apX,apY)] = (200, 0, 0)

def posInSnake(x, y, begin=0):
    global snakelst
    end = len(snakelst)-begin
    isit = False
    for glied in snakelst[:end]:
        if glied[0]==x and glied[1]==y:
            isit = True
    return isit

def snakeMove(dir):
    global kopfX, kopfY, snakelst, lenght, apX, apY, score
    if dir == 'n':
        kopfY -= 1
    elif dir == 's':
        kopfY += 1
    elif dir == 'e':
        kopfX += 1
    elif dir == 'w':
        kopfX -= 1
    np[c(kopfX,kopfY)] = (0, 0, 255)
    if dir != '':
        snakelst += [ (kopfX, kopfY) ]
        if len(snakelst) > lenght:
            end = snakelst.pop(0)
            clsPix(end[0], end[1])
    if kopfX==apX and kopfY==apY:
        lenght += 1
        score += 1
        lcd.clear()
        lcd.putstr("Score:" + str(score))
        newApple()
    if not(0<=kopfX<=7 and 0<=kopfY<=7) or posInSnake(kopfX, kopfY, 1):
        for i in range(0, 64):
            np[i] = (0, 0, 0)
        for i in range(0, 8):
            np[c(i, i)] = (200, 0, 0)
            np[c(i, 7-i)] = (200, 0, 0)
        np.write()
        sleep(1)
        newGame()

def clsPix(x, y):
    if (x+y)%2==0:
        np[c(x,y)] = (50, 100, 50)
    else:
        np[c(x,y)] = (50, 100, 00)

def newGame():
    global kopfX, kopfY, apX, apY, snakelst, score, lenght, dir
    for x in range(0, 8):
        for y in range(0, 8):
            clsPix(x, y)
    kopfX = randint(-1, 6)
    kopfY = randint(0, 7)

    score = 0
    lcd.clear()
    lcd.putstr("Score:" + str(score))

    snakelst = [ (kopfX, kopfY) ]
    lenght = 1
    dir = ''
    apX = randint(0, 7)
    apY = randint(0, 7)
    snakeMove('e')
    newApple()
    np.write()

######### main ##################
Up = Pin(18, Pin.IN, Pin.PULL_DOWN)
Up.irq(trigger=Pin.IRQ_RISING, handler=pressUp)
Down = Pin(17, Pin.IN, Pin.PULL_DOWN)
Down.irq(trigger=Pin.IRQ_RISING, handler=pressDown)
Left = Pin(16, Pin.IN, Pin.PULL_DOWN)
Left.irq(trigger=Pin.IRQ_RISING, handler=pressLeft)
Right = Pin(19, Pin.IN, Pin.PULL_DOWN)
Right.irq(trigger=Pin.IRQ_RISING, handler=pressRight)
pin = Pin(0, Pin.OUT)
np = NeoPixel(pin, 64)

newGame()
while True:
    snakeMove(dir)
    np.write()
    sleep(.5)