type ExtractArgs<T extends object> = T[keyof T] extends (...args: infer A) => any ? A : any[];
type EventState<T extends object, Args extends unknown[] = ExtractArgs<T>> = T & {
    (key?: keyof T, fun?: T[keyof T]): EventState<T, Args>;
    (target?: Partial<T>): EventState<T, Args>;
};

interface KeyState<El extends Element = Element> {
    target: El | Window;
    pressedKey: string;
    code: string;
    event: KeyboardEvent;
    key(e: KeyState): void;
    keydown(e: KeyboardEvent): void;
    mount(el: El): void;
    clean(el: null): void;
    ref(el: Element | null): void;
}
type KeyArg<El extends Element = Element> = Partial<KeyState<El>> | KeyState<El>['key'];

declare const keyEvent: <El extends Element = Element>(state?: Partial<KeyState<El>>) => EventState<KeyState<El>>;

export { type KeyArg, type KeyState, keyEvent };