import { useEffect, useRef, useState } from 'react';
import { isTypingTarget } from '@/lib/keyboard';

interface UseTapGestureOptions {
  /** Detected against KeyboardEvent.key. */
  targetKey: string;
  /** Optional KeyboardEvent.code fallback (e.g. 'Backquote'). */
  targetCode?: string;
  /** Taps required before `satisfied` flips true. Defaults to 1. */
  taps?: number;
  /** Fires on each counted tap, with the new running count. */
  onTap?: (count: number) => void;
}

/**
 * Counts discrete taps of a single key, ignoring auto-repeat. Used both for the
 * one-tap audio/video toggle and the two-tap start/stop demonstration.
 */
export function useTapGesture({
  targetKey,
  targetCode,
  taps = 1,
  onTap,
}: UseTapGestureOptions) {
  const [count, setCount] = useState(0);

  const onTapRef = useRef(onTap);
  useEffect(() => {
    onTapRef.current = onTap;
  });

  useEffect(() => {
    const matches = (e: KeyboardEvent) =>
      e.key === targetKey || (targetCode != null && e.code === targetCode);

    const handleKeyDown = (e: KeyboardEvent) => {
      if (e.repeat || isTypingTarget(e) || !matches(e)) return;
      e.preventDefault();
      setCount((prev) => {
        if (prev >= taps) return prev;
        const next = prev + 1;
        onTapRef.current?.(next);
        return next;
      });
    };

    window.addEventListener('keydown', handleKeyDown);
    return () => window.removeEventListener('keydown', handleKeyDown);
  }, [targetKey, targetCode, taps]);

  return { taps: count, satisfied: count >= taps };
}