from __future__ import annotations

HOTKEY_MODIFIERS = {
    "shift",
    "ctrl",
    "control",
    "alt",
    "mod1",
    "super",
    "mod4",
    "cmd",
    "command",
}


def split_hotkey(hotkey: str) -> tuple[list[str], str]:
    parts = [p.strip() for p in hotkey.split("+") if p.strip()]
    modifiers: list[str] = []
    key_part = ""
    for part in parts:
        low = part.lower()
        if low in HOTKEY_MODIFIERS:
            modifiers.append(low)
            continue
        if key_part:
            raise ValueError("must include exactly one non-modifier key")
        key_part = part
    if not key_part:
        raise ValueError("missing key")
    return modifiers, key_part