#!/usr/bin/env python3
"""Compiles themes for wasp-os"""

from argparse import ArgumentParser, RawTextHelpFormatter
from importlib import import_module
from typing import Tuple

class DefaultTheme():
    """This represents the default theme.

    Import this file and extend the Theme class, only changing the variables.
    Export the resulting class as 'Theme'.
    serialize() should NEVER be overriden!
    """
    BLE_COLOR = 0x7bef
    SCROLL_INDICATOR_COLOR = 0x7bef
    BATTERY_COLOR = 0x7bef
    SMALL_CLOCK_COLOR = 0xe73c
    NOTIFICATION_COLOR = 0x7bef
    ACCENT_MID = 0xb5b6
    ACCENT_LO = 0xbdb6
    ACCENT_HI = 0xffff
    SLIDER_DEFAULT_COLOR = 0x39ff

    def serialize(self) -> bytes:
        """Serializes the theme for use in wasp-os"""
        def split_bytes(x: int) -> Tuple[int, int]:
            return (x & 0xFF, (x >> 8) & 0xFF)
        theme_bytes = bytes([
            *split_bytes(self.BLE_COLOR),
            *split_bytes(self.SCROLL_INDICATOR_COLOR),
            *split_bytes(self.BATTERY_COLOR),
            *split_bytes(self.SMALL_CLOCK_COLOR),
            *split_bytes(self.NOTIFICATION_COLOR),
            *split_bytes(self.ACCENT_MID),
            *split_bytes(self.ACCENT_LO),
            *split_bytes(self.ACCENT_HI),
            *split_bytes(self.SLIDER_DEFAULT_COLOR),
        ])
        return theme_bytes


if __name__ == '__main__':
    parser = ArgumentParser(
        description='''Compiles themes into a format understood by wasp-os.
                       The resulting string should be put in main.py like this:

                           theme_string = THEME_STRING_GOES_HERE

                       for the theme to take effect.
                    ''',
        epilog=''' To create a theme,
               import this file and extend the DefaultTheme class, only changing the variables.
               Export the resulting class as 'Theme'.
               Example:
               --------
               theme.py:
                   from themer import DefaultTheme

                   class Theme(DefaultTheme):
                       BLE_ICON_COLOR = 0x041F

               shell:
                   $ ./themer.py theme # NOTE: do not include .py at end of file!
                   > b'\xef{\xef{\xef{<\xe7\xef{\xb6\xb5\xb6\xbd\xff\xff\xff9'

               main.py:
                   ...
                   wasp.system.set_theme(b'\xef{\xef{\xef{<\xe7\xef{\xb6\xb5\xb6\xbd\xff\xff\xff9')
                   ...
               ''',
        formatter_class=RawTextHelpFormatter
    )

    parser.add_argument('input_file', type=str, nargs=1)
    args = parser.parse_args()

    theme = DefaultTheme()
    theme = import_module(args.input_file[0]).Theme()
    print(theme.serialize())