(function initSearchResultsPage() {
  const API_ENDPOINT = "https://app.litenews.cn/v1/app/search/special";
  const API_ORG_ID = "275";
  const API_PAGE_SIZE = 10;
  let activeRequestToken = 0;

  function escapeHtml(value) {
    return String(value)
      .replace(/&/g, "&")
      .replace(/</g, "&lt;")
      .replace(/>/g, "&gt;")
      .replace(/"/g, "&quot;")
      .replace(/'/g, "&#39;");
  }

  function escapeRegExp(value) {
    return value.replace(/[.*+?^${}()|[\]\\]/g, "\\$&");
  }

  function highlightText(text, keyword) {
    if (!keyword) {
      return escapeHtml(text);
    }

    const matcher = new RegExp(escapeRegExp(keyword), "gi");
    let cursor = 0;
    let output = "";
    let match;

    while ((match = matcher.exec(text)) !== null) {
      output += escapeHtml(text.slice(cursor, match.index));
      output += `<mark class="search-highlight">${escapeHtml(match[0])}</mark>`;
      cursor = match.index + match[0].length;
    }

    output += escapeHtml(text.slice(cursor));
    return output;
  }

  function getSearchState() {
    const url = new URL(window.location.href);
    const keyword = (url.searchParams.get("keyword") || "").trim();
    const page = Math.max(1, Number.parseInt(url.searchParams.get("page") || "1", 10) || 1);
    return { keyword, page };
  }

  function buildUrl(keyword, page) {
    const url = new URL(window.location.href);

    if (keyword) {
      url.searchParams.set("keyword", keyword);
      url.searchParams.set("page", String(page));
    } else {
      url.searchParams.delete("keyword");
      url.searchParams.delete("page");
    }

    return url;
  }

  function setLoadingState(isLoading) {
    const submit = document.querySelector(".search-results-submit");
    const input = document.querySelector("[data-search-input]");

    if (submit) {
      submit.disabled = isLoading;
      submit.textContent = isLoading ? "搜索中" : "搜索";
    }

    if (input) {
      input.disabled = isLoading;
    }
  }

  function createPaginationButton(label, options) {
    const button = document.createElement("button");
    button.type = "button";
    button.className = "search-results-page-btn";
    button.textContent = label;

    if (options.width === "wide") {
      button.style.minWidth = "3.9375rem";
    }

    if (options.disabled) {
      button.disabled = true;
      button.classList.add("is-disabled");
    }

    if (options.active) {
      button.classList.add("is-active");
      button.setAttribute("aria-current", "page");
    }

    if (typeof options.page === "number" && !options.disabled) {
      button.dataset.page = String(options.page);
    }

    return button;
  }

  function getVisiblePages(currentPage, pageCount) {
    const maxVisible = 6;

    if (pageCount <= maxVisible) {
      return Array.from({ length: pageCount }, (_, index) => index + 1);
    }

    let start = Math.max(1, currentPage - Math.floor(maxVisible / 2));
    let end = start + maxVisible - 1;

    if (end > pageCount) {
      end = pageCount;
      start = end - maxVisible + 1;
    }

    return Array.from({ length: end - start + 1 }, (_, index) => start + index);
  }

  function renderEmptyState() {
    const list = document.querySelector("[data-results-list]");
    const emptyState = document.querySelector("[data-empty-state]");
    const pagination = document.querySelector("[data-pagination]");

    if (list) {
      list.innerHTML = "";
    }

    if (emptyState) {
      emptyState.hidden = false;
    }

    if (pagination) {
      pagination.hidden = true;
      pagination.innerHTML = "";
    }
  }

  function renderResults(keyword, pageData) {
    const list = document.querySelector("[data-results-list]");
    const emptyState = document.querySelector("[data-empty-state]");
    const pagination = document.querySelector("[data-pagination]");

    if (!list || !emptyState || !pagination) {
      return;
    }

    const infos = Array.isArray(pageData.infos) ? pageData.infos : [];
    const total = Number(pageData.total) || 0;
    const pageCount = Math.max(1, Math.ceil(total / API_PAGE_SIZE));
    const currentPage = Math.max(1, Math.min(Number(pageData.page) || 1, pageCount));

    if (!infos.length) {
      renderEmptyState();
      return;
    }

    emptyState.hidden = true;
    list.innerHTML = infos.map((item) => {
      const title = item.title || "";
      const summary = item.desc || "";
      const date = item.publish_at || "";
      const url = item._url || item.link || item.url || "./news-detail.html";

      return `
        <article class="search-result-item">
          <a class="search-result-link" href="${escapeHtml(url)}" target="_self">
            <h2 class="search-result-title">${highlightText(title, keyword)}</h2>
            <p class="search-result-summary">${highlightText(summary, keyword)}</p>
            <time class="search-result-date" datetime="${escapeHtml(date)}">${escapeHtml(date)}</time>
          </a>
        </article>
      `;
    }).join("");

    pagination.hidden = pageCount <= 1;
    pagination.innerHTML = "";

    if (pageCount <= 1) {
      return;
    }

    const controls = [
      createPaginationButton("首页", { page: 1, width: "wide", disabled: currentPage === 1 }),
      createPaginationButton("上一页", { page: currentPage - 1, width: "wide", disabled: currentPage === 1 }),
    ];

    const visiblePages = getVisiblePages(currentPage, pageCount);

    for (const index of visiblePages) {
      controls.push(createPaginationButton(String(index), { page: index, active: index === currentPage }));
    }

    controls.push(
      createPaginationButton("下一页", { page: currentPage + 1, width: "wide", disabled: currentPage === pageCount }),
      createPaginationButton("末页", { page: pageCount, width: "wide", disabled: currentPage === pageCount }),
    );

    controls.forEach((button) => {
      pagination.appendChild(button);
    });
  }

  function requestSearch(keyword, page) {
    return new Promise((resolve, reject) => {
      const callbackName = `codexSearchJsonp_${Date.now()}_${Math.random().toString(16).slice(2)}`;
      const script = document.createElement("script");
      const timer = window.setTimeout(() => {
        cleanup();
        reject(new Error("Search request timed out"));
      }, 10000);

      function cleanup() {
        window.clearTimeout(timer);
        if (script.parentNode) {
          script.parentNode.removeChild(script);
        }
        try {
          delete window[callbackName];
        } catch (error) {
          window[callbackName] = undefined;
        }
      }

      window[callbackName] = (payload) => {
        cleanup();
        resolve(payload);
      };

      script.onerror = () => {
        cleanup();
        reject(new Error("Search request failed"));
      };

      const url = new URL(API_ENDPOINT);
      url.searchParams.set("_orgid_", API_ORG_ID);
      url.searchParams.set("keyword", keyword);
      url.searchParams.set("page", String(page));
      url.searchParams.set("cqcallback", callbackName);
      url.searchParams.set("_", String(Date.now()));
      script.src = url.toString();
      document.body.appendChild(script);
    });
  }

  async function render() {
    const input = document.querySelector("[data-search-input]");
    if (!input) {
      return;
    }

    const { keyword, page } = getSearchState();
    const requestToken = ++activeRequestToken;

    input.value = keyword;

    if (!keyword) {
      renderEmptyState();
      return;
    }

    setLoadingState(true);

    try {
      const response = await requestSearch(keyword, page);
      if (requestToken !== activeRequestToken) {
        return;
      }

      if (!response || Number(response.code) !== 1 || !response.data) {
        renderEmptyState();
        return;
      }

      renderResults(keyword, {
        infos: response.data.infos || [],
        total: response.data.total || 0,
        page,
      });
    } catch (error) {
      if (requestToken === activeRequestToken) {
        renderEmptyState();
      }
    } finally {
      if (requestToken === activeRequestToken) {
        setLoadingState(false);
      }
    }
  }

  function bindEvents() {
    const form = document.querySelector("[data-search-form]");
    const pagination = document.querySelector("[data-pagination]");

    if (!form || !pagination) {
      return;
    }

    form.addEventListener("submit", (event) => {
      event.preventDefault();
      const input = form.querySelector("[data-search-input]");
      const keyword = input ? input.value.trim() : "";
      const nextUrl = buildUrl(keyword, 1);

      window.history.replaceState({}, "", nextUrl);
      render();
    });

    pagination.addEventListener("click", (event) => {
      const trigger = event.target.closest("[data-page]");
      if (!trigger) {
        return;
      }

      const { keyword } = getSearchState();
      const page = Number.parseInt(trigger.dataset.page || "1", 10) || 1;
      const nextUrl = buildUrl(keyword, page);

      window.history.replaceState({}, "", nextUrl);
      render();
      // window.scrollTo({ top: 0, behavior: "smooth" });
    });
  }

  if (document.readyState === "loading") {
    document.addEventListener("DOMContentLoaded", () => {
      bindEvents();
      render();
    }, { once: true });
  } else {
    bindEvents();
    render();
  }
})();