import struct
import ctypes
from time import sleep

from serial import Serial


LEDCOUNT = 30
BAUDRATE = 115200

data = ctypes.create_string_buffer(6)
# magic word + led number + checksum which are recognized as valid by my adalight
struct.pack_into(">3s", data, 0, "Ada")
struct.pack_into(">H", data, 3, LEDCOUNT)
HEADER = bytearray(data)
HEADER[5] = HEADER[3] ^ HEADER[4] ^ 0x55

# special header to set all leds to the same color (saves serial bandwidth)
# requires special handling in the sketch
ALLHEADER = ['A', 'd', 'a', 0xff, 0xff, 0x55]

arduino = Serial('COM6', BAUDRATE)

LEDBYTES = LEDCOUNT * 3  # r,g,b bytes
LEDBUF = [0] * LEDBYTES  # buffer


def setLedColor(num, r, g, b):
    idx = num * 3
    LEDBUF[idx] = chr(r)
    LEDBUF[idx + 1] = chr(g)
    LEDBUF[idx + 2] = chr(b)


def setAllLedsFast(r, g, b):
    arduino.write(ALLHEADER)
    arduino.write(chr(r))
    arduino.write(chr(g))
    arduino.write(chr(b))
    arduino.flushOutput()


def setAllLeds(r, g, b):
    for idx in range(0, LEDCOUNT):
        setLedColor(idx, r, g, b)
    display()


def display():
    arduino.write(HEADER)
    arduino.write(LEDBUF)
    arduino.flushOutput()


def setStripColor(c):
    if (c <= 255):
        r = 255 - c
        g = c
        b = 0
    elif (c <= 511):
        r = 0
        g = 255 - (c - 256)
        b = c - 256
    else:
        r = c - 512
        g = 0
        b = 255 - (c - 512)
    setAllLedsFast(r, g, b)
    sleep(0.01)


def checkColors():
    for c in range(0, 768):
        setStripColor(c)
    for c in range(0, 768):
        setStripColor(768 - c - 1)


while 1:
    sleep(2)  # wait for Arduiono initialization after reset
    setAllLeds(0x00, 0x00, 0x00)
    sleep(1)
    setAllLeds(0xff, 0x00, 0x00)
    sleep(1)
    setAllLedsFast(0x00, 0xff, 0x00)
    sleep(1)
    setAllLedsFast(0x00, 0x00, 0xff)
    sleep(1)
    checkColors()

    for i in range(0, 4):
        setAllLedsFast(0x00, 0x00, 0x00)
        LEDBUF = [0] * LEDBYTES
        sleep(1)
        for n in range(0, LEDCOUNT):
            if i % 2 == 0:
                LEDBUF = [0] * LEDBYTES
                if i % 4 == 0:
                    setLedColor(n, 0xff, 0xff, 0xff)
                else:
                    setLedColor(LEDCOUNT - n - 1, 0xff, 0xff, 0xff)
            else:
                setLedColor(n, 0x00, 0x00, 0xff)

            display()
            sleep(0.02)