import { useEffect, useRef, useState } from 'react';

interface UseScrollRevealOptions {
  threshold?: number;
  rootMargin?: string;
  triggerOnce?: boolean;
}

export function useScrollReveal({
  threshold = 0.1,
  rootMargin = '0px',
  triggerOnce = true,
}: UseScrollRevealOptions = {}) {
  const ref = useRef<HTMLElement>(null);
  const [isVisible, setIsVisible] = useState(false);

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

    const observer = new IntersectionObserver(
      ([entry]) => {
        if (entry.isIntersecting) {
          setIsVisible(true);
          if (triggerOnce) {
            observer.unobserve(element);
          }
        } else if (!triggerOnce) {
          setIsVisible(false);
        }
      },
      { threshold, rootMargin }
    );

    observer.observe(element);

    return () => observer.disconnect();
  }, [threshold, rootMargin, triggerOnce]);

  return { ref, isVisible };
}

interface UseScrollProgressOptions {
  threshold?: number;
}

export function useScrollProgress({ threshold = 0 }: UseScrollProgressOptions = {}) {
  const [progress, setProgress] = useState(0);

  useEffect(() => {
    const handleScroll = () => {
      const scrollTop = window.pageYOffset;
      const docHeight = document.documentElement.scrollHeight - window.innerHeight;
      const scrollProgress = scrollTop / docHeight;
      setProgress(Math.min(1, Math.max(0, scrollProgress)));
    };

    window.addEventListener('scroll', handleScroll, { passive: true });
    handleScroll();

    return () => window.removeEventListener('scroll', handleScroll);
  }, []);

  return progress;
}

interface UseParallaxOptions {
  speed?: number;
}

export function useParallax({ speed = 0.5 }: UseParallaxOptions = {}) {
  const ref = useRef<HTMLElement>(null);
  const [offset, setOffset] = useState(0);

  useEffect(() => {
    const handleScroll = () => {
      if (!ref.current) return;
      
      const rect = ref.current.getBoundingClientRect();
      const scrolled = window.pageYOffset;
      const elementTop = rect.top + scrolled;
      const parallaxOffset = (scrolled - elementTop) * speed;
      
      setOffset(parallaxOffset);
    };

    window.addEventListener('scroll', handleScroll, { passive: true });
    handleScroll();

    return () => window.removeEventListener('scroll', handleScroll);
  }, [speed]);

  return { ref, offset };
}