import json
import pathlib

import gnuradio.gr
import numpy


class MessageGeneratorBlock(gnuradio.gr.basic_block):
    def __init__(self):
        gnuradio.gr.basic_block.__init__(
            self, name="Message Generator", in_sig=None, out_sig=[numpy.uint8]
        )
        # __file__ is not available
        self._messages = json.loads(
            pathlib.Path().resolve().parent.joinpath("messages.json").read_text()
        )

    def general_work(self, input_items, output_items) -> int:
        # pylint: disable=unused-argument
        message = self._messages["ON0"] + [0] * 128
        if len(output_items[0]) < len(message):
            print("output buffer too short", len(output_items[0]))
            output_items[0][:] = 0
            return len(output_items[0])
        output_items[0][: len(message)] = message
        return len(message)