"use client";

import { useEffect, useRef, useState, type ElementType, type ReactNode } from "react";

export function Reveal({
  children,
  as: Tag = "div",
  delay = 0,
  className = "",
}: {
  children: ReactNode;
  as?: ElementType;
  delay?: number;
  className?: string;
}) {
  const ref = useRef<HTMLElement | null>(null);
  const [shown, setShown] = useState(false);

  useEffect(() => {
    const el = ref.current;
    if (!el) return;

    const io = new IntersectionObserver(
      (entries) => {
        for (const entry of entries) {
          if (entry.isIntersecting) {
            setShown(true);
            io.disconnect();
          }
        }
      },
      { rootMargin: "0px 0px -10% 0px", threshold: 0.15 },
    );
    io.observe(el);
    return () => io.disconnect();
  }, []);

  return (
    <Tag
      ref={ref}
      data-shown={shown ? "" : undefined}
      style={{ transitionDelay: `${delay}ms` }}
      className={`reveal ${className}`}
    >
      {children}
    </Tag>
  );
}