(function () {
  "use strict";

  const delay = ms => new Promise(resolve => setTimeout(resolve, ms));

  function freezeAnimations() {
    const style = document.createElement("style");
    style.id = "__web-to-ppt-freeze";
    style.textContent = `
      *, *::before, *::after {
        animation-play-state: paused !important;
        transition-duration: 0s !important;
        scroll-behavior: auto !important;
      }
      .slick-track,
      .swiper-wrapper {
        transition-duration: 0s !important;
      }
    `;
    document.documentElement.appendChild(style);

    for (const media of document.querySelectorAll("video, audio")) {
      try {
        media.pause();
      } catch {
        // Ignore media elements that cannot be controlled by content scripts.
      }
    }
  }

  function stabilizeCarousels() {
    try {
      if (window.jQuery) {
        window.jQuery(".slick-slider").each((_, element) => {
          try {
            window.jQuery(element).slick("slickPause");
            window.jQuery(element).slick("slickGoTo", 0, true);
          } catch {
            // Some pages expose slick classes without the jQuery plugin instance.
          }
        });
      }
    } catch {
      // Best effort only.
    }

    for (const element of document.querySelectorAll(".swiper, .swiper-container")) {
      try {
        if (element.swiper) {
          element.swiper.autoplay?.stop?.();
          element.swiper.slideToLoop?.(0, 0, false);
          element.swiper.slideTo?.(0, 0, false);
          element.swiper.update?.();
        }
      } catch {
        // Keep DOM capture running even if a carousel API rejects.
      }
    }

    for (const wrapper of document.querySelectorAll(".swiper-wrapper, .slick-track")) {
      wrapper.style.transitionDuration = "0s";
      wrapper.style.animationPlayState = "paused";
    }
  }

  async function waitForStableTopLayer(timeout = 2500) {
    const start = Date.now();
    const selector = [
      "header",
      "nav",
      "[role='navigation']",
      "[class*='header' i]",
      "[class*='nav' i]",
      "[class*='top' i]"
    ].join(",");

    while (Date.now() - start < timeout) {
      const candidates = Array.from(document.querySelectorAll(selector));
      const hasVisibleCandidate = candidates.some(element => {
        const rect = element.getBoundingClientRect();
        const style = window.getComputedStyle(element);
        return rect.width > 20 &&
          rect.height > 10 &&
          rect.bottom >= 0 &&
          rect.top < Math.max(160, window.innerHeight * 0.2) &&
          style.display !== "none" &&
          style.visibility !== "hidden" &&
          Number(style.opacity || 1) > 0;
      });
      if (hasVisibleCandidate || document.readyState === "complete") {
        await delay(300);
        return;
      }
      await delay(120);
    }
  }

  async function scrollToLoadLazyContent() {
    const maxScroll = Math.max(
      document.documentElement.scrollHeight,
      document.body.scrollHeight
    ) - window.innerHeight;

    if (maxScroll <= 0) return;

    const step = Math.max(480, Math.floor(window.innerHeight * 0.8));
    for (let y = 0; y <= maxScroll; y += step) {
      window.scrollTo(0, Math.min(y, maxScroll));
      await delay(160);
    }

    window.scrollTo(0, maxScroll);
    await delay(220);
    window.scrollTo(0, 0);
    await delay(220);
  }

  async function waitForImages(timeout = 3500) {
    const images = Array.from(document.images || []);
    await Promise.race([
      Promise.allSettled(images.map(image => {
        if (image.complete) return Promise.resolve();
        return new Promise(resolve => {
          image.addEventListener("load", resolve, { once: true });
          image.addEventListener("error", resolve, { once: true });
        });
      })),
      delay(timeout)
    ]);
  }

  async function waitForFonts(timeout = 3000) {
    if (!document.fonts?.ready) return;
    await Promise.race([document.fonts.ready, delay(timeout)]);
  }

  window.__webToPPTRunCapture = async function runCapture(options = {}) {
    if (!window.__webToPPTCapture) {
      throw new Error("采集引擎未加载");
    }

    freezeAnimations();
    stabilizeCarousels();
    await waitForStableTopLayer();
    stabilizeCarousels();
    await scrollToLoadLazyContent();
    stabilizeCarousels();
    await waitForImages();
    await waitForFonts();
    stabilizeCarousels();
    await delay(200);

    return window.__webToPPTCapture({
      useProxy: Boolean(options.useProxy),
      concurrency: options.concurrency || "8",
      captureMode: options.captureMode === "editable" ? "editable" : "mixed",
      captureWidth: options.captureWidth,
      selectionId: options.selectionId,
      selectionWidth: options.selectionWidth
    });
  };
})();