bulb.py

#!/usr/bin/env python3
"""
bulb.py
~~~~~~~

This module is for communicating with the MagicHome LED bulb over TCP.

Wire protocol (bytes):

-------------------------------------
|header(1)|data(5-70)|0f|checksum(1)|
-------------------------------------

header (mode):
    31 color & white (standard color changing)
    41 camera (smoother color changing)
    51 custom (user-defined things)
    61 function (predefined functions)

color, white, camera (8 bytes):
    00-ff red
    00-ff green
    00-ff blue
    00-ff white
    mode:
        0f white
        f0 color

functions (5 bytes):
    25-38 modes
    1f-01 speed (decreasing)

custom (70 bytes):
    64 bytes of r, g, b, 0 (empty color is 0x01020300)
    1f-01 speed (decreasing)
    3a,3b,3c gradual, jumping, strobe
    ff tail

tail:
    0f
    checksum (sum of data fields)
"""
import socket
import sys

SUPPORTED_MODES = ['31', '41', '61']
SUPPORTED_FUNCTIONS = list(range(25, 39))
TAIL = '0f'

prepare_hex = lambda x: format(x, 'x').zfill(2)


class Bulb:
    """
    A class representing a single MagicHome LED Bulb.
    """

    def __init__(self, host):
        self.host = host

    def change_color(self, red=0, green=0, blue=0, white=0, brightness=100, mode='31', function=None, speed='1f'):
        """
        Provided RGB values, change the color of the
        bulb with a TCP socket.
        """
        if mode not in SUPPORTED_MODES:
            raise NotImplementedError

        if function:
            if num(function) not in SUPPORTED_FUNCTIONS:
                raise NotImplementedError
            data = bytearray.fromhex(mode + function + speed + TAIL)
        else:
            red = int(red * brightness / 100)
            green = int(green * brightness / 100)
            blue = int(blue * brightness / 100)
            white = int(white * brightness / 100)
            color_hex = (prepare_hex(red) + prepare_hex(green) + prepare_hex(blue)
                         + prepare_hex(white))
            if white:
                color_mode = '0f'
            else:
                color_mode = 'f0'
            # Build packet
            data = bytearray.fromhex(mode + color_hex
                                     + color_mode + TAIL)
        s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        try:
            # TCP port 5577
            s.connect((self.host, 5577))
            # Compute checksum
            data.append(sum(data) % 256)
            s.send(data)
        except Exception as e:
            print(str(e))


if __name__ == '__main__':
    if len(sys.argv) < 4:
        sys.exit('Nope')
    colors = list(map(lambda x: int(x), sys.argv[1:]))
    print(colors)
    b = Bulb()
    b.change_color(*colors)