from typing import Tuple, TypedDict

from snanosm.mealy import Machine

class Context(TypedDict):
    result: str
    n_chars: int

def add_to_result(context: Context, c: str) -> None:
    context["result"] += c
    context["n_chars"] += 1

def inverter(input_string: str) -> Tuple[str, int]:
    context: Context = {
        "result": "",
        "n_chars": 0
    }
    m = Machine(context)
    m.add_state("S", True, False)
    m.add_transition("0", "S", "S", lambda ctx: add_to_result(ctx, "1"))
    m.add_transition("1", "S", "S", lambda ctx: add_to_result(ctx, "0"))
    for c in input_string:
        m.process_input(c)
    return context["result"], context["n_chars"]

if __name__ == '__main__':
    print(inverter("000011110010"))