from typing import List, Optional

from .key_processor import KeyPress

__all__ = [
    "EmacsState",
]


class EmacsState:
    """
    Mutable class to hold Emacs specific state.
    """

    def __init__(self) -> None:
        # Simple macro recording. (Like Readline does.)
        # (For Emacs mode.)
        self.macro: Optional[List[KeyPress]] = []
        self.current_recording: Optional[List[KeyPress]] = None

    def reset(self) -> None:
        self.current_recording = None

    @property
    def is_recording(self) -> bool:
        "Tell whether we are recording a macro."
        return self.current_recording is not None

    def start_macro(self) -> None:
        "Start recording macro."
        self.current_recording = []

    def end_macro(self) -> None:
        "End recording macro."
        self.macro = self.current_recording
        self.current_recording = None