import { useLayoutEffect } from "react";
import { gsap } from "gsap";
import { ScrollTrigger } from "gsap/ScrollTrigger";

let pluginsRegistered = false;

const registerGsap = () => {
  if (!pluginsRegistered) {
    gsap.registerPlugin(ScrollTrigger);
    pluginsRegistered = true;
  }
};

const createRevealLines = (element) => {
  if (!element) {
    return [];
  }

  if (element.dataset.revealPrepared === "true") {
    return Array.from(element.querySelectorAll(".reveal-line"));
  }

  const originalHtml = element.innerHTML;
  const segments = originalHtml
    .split(/<br\s*\/?>/i)
    .map((segment) => segment.trim())
    .filter(Boolean);

  if (segments.length === 0) {
    return [];
  }

  element.dataset.revealPrepared = "true";
  element.dataset.revealOriginalHtml = originalHtml;
  element.innerHTML = segments
    .map(
      (segment) =>
        `<span class="reveal-line-mask"><span class="reveal-line">${segment}</span></span>`
    )
    .join("");

  return Array.from(element.querySelectorAll(".reveal-line"));
};

const restoreRevealLines = (element) => {
  if (!element || element.dataset.revealPrepared !== "true") {
    return;
  }

  const originalHtml = element.dataset.revealOriginalHtml;

  if (originalHtml) {
    element.innerHTML = originalHtml;
  }

  delete element.dataset.revealPrepared;
  delete element.dataset.revealOriginalHtml;
};

function useScrollTextReveal(scopeRef, dependencyKey = "") {
  useLayoutEffect(() => {
    const scope = scopeRef.current;

    if (!scope || typeof window === "undefined") {
      return undefined;
    }

    if (window.matchMedia("(prefers-reduced-motion: reduce)").matches) {
      return undefined;
    }

    registerGsap();

    const preparedElements = [];
    const ctx = gsap.context(() => {
      const groups = gsap.utils.toArray("[data-reveal-group]");

      groups.forEach((group) => {
        const items = Array.from(group.querySelectorAll("[data-reveal]")).filter(
          (item) => item.closest("[data-reveal-group]") === group
        );

        if (items.length === 0) {
          return;
        }

        items.forEach((item) => {
          if (item.dataset.reveal === "lines") {
            gsap.set(item, { autoAlpha: 0 });
            return;
          }

          gsap.set(item, {
            y: 36,
            autoAlpha: 0,
            force3D: true,
          });
        });

        ScrollTrigger.create({
          trigger: group,
          start: group.dataset.revealStart || "top 86%",
          once: true,
          onEnter: () => {
            const timeline = gsap.timeline();

            items.forEach((item, index) => {
              const position = index === 0 ? 0 : "<0.16";

              if (item.dataset.reveal === "lines") {
                const lines = createRevealLines(item);

                if (lines.length === 0) {
                  return;
                }

                preparedElements.push(item);
                gsap.set(item, { autoAlpha: 1 });
                gsap.set(lines, {
                  yPercent: 115,
                  rotate: 2.2,
                  transformOrigin: "0% 100%",
                  force3D: true,
                });

                timeline.to(
                  lines,
                  {
                    yPercent: 0,
                    rotate: 0,
                    duration: 1.18,
                    stagger: 0.1,
                    ease: "power4.out",
                    clearProps: "transform",
                  },
                  position
                );

                return;
              }

              timeline.to(
                item,
                {
                  y: 0,
                  autoAlpha: 1,
                  duration: 1.02,
                  ease: "power4.out",
                  clearProps: "transform,opacity,visibility",
                },
                position
              );
            });
          },
        });
      });

      ScrollTrigger.refresh();
    }, scope);

    return () => {
      ctx.revert();
      preparedElements.forEach((element) => restoreRevealLines(element));
    };
  }, [scopeRef, dependencyKey]);
}

export default useScrollTextReveal;