import { t, setLanguage, getLanguage, initI18n, onLanguageChange, faqMarkdown } from "./js/i18n.js";
import { state, clearUserState } from "./js/state.js";
import { toast } from "./js/dom.js";
import {
  handleAuthError,
  renderWelcome,
  renderPhasePill,
  renderCounts,
  renderMySuggestions,
  renderAllSuggestions,
  renderVotes,
  syncVoteScores,
  renderResults,
  renderPhaseTitles,
  updatePhaseNav,
  configureUiRuntime,
} from "./js/ui.js";
import {
  loadSuggestData,
  loadVoteData,
  refreshPhaseData,
} from "./js/data.js";
import { setupAuthHandlers } from "./js/app-auth-handlers.js";
import { setupAdminHandlers } from "./js/app-admin-handlers.js";
import { setupVoteNavigationHandlers } from "./js/app-vote-nav-handlers.js";

const REFRESH_INTERVAL_MS = 4000;
let refreshInFlight = null;
let refreshTimerId = null;
let refreshSchedulerStarted = false;

async function runSerializedRefresh() {
  if (refreshInFlight) return refreshInFlight;
  refreshInFlight = refreshPhaseData().finally(() => {
    refreshInFlight = null;
  });
  return refreshInFlight;
}

async function refreshWithUiErrorHandling() {
  try {
    await runSerializedRefresh();
  } catch (err) {
    if (!handleAuthError(err, clearUserState)) toast(err.message, true);
  }
}

function scheduleNextRefresh() {
  refreshTimerId = window.setTimeout(async () => {
    if (!document.hidden && !state.adminStatusSelectActive) {
      await refreshWithUiErrorHandling();
    }
    scheduleNextRefresh();
  }, REFRESH_INTERVAL_MS);
}

function startRefreshScheduler() {
  if (refreshSchedulerStarted) return;
  refreshSchedulerStarted = true;

  document.addEventListener("visibilitychange", () => {
    if (!document.hidden && !state.adminStatusSelectActive) {
      refreshWithUiErrorHandling();
    }
  });

  if (refreshTimerId !== null) {
    window.clearTimeout(refreshTimerId);
  }
  scheduleNextRefresh();
}

configureUiRuntime({
  refreshPhaseData: runSerializedRefresh,
  loadSuggestData,
  loadVoteData,
  handleAuthError: (err) => handleAuthError(err, clearUserState),
});

function setupHandlers() {
  setupAuthHandlers({ runSerializedRefresh });
  setupAdminHandlers({ runSerializedRefresh });
  setupVoteNavigationHandlers({ runSerializedRefresh });
  setupLanguageSwitchers();

  onLanguageChange(() => {
    updateLanguageButtons();
    renderWelcome();
    renderPhasePill();
    renderCounts();
    renderPhaseTitles();
    renderMySuggestions();
    renderAllSuggestions();
    if (state.phase === "Vote") {
      renderVotes();
      state.votesRendered = true;
      syncVoteScores();
    }
    if (state.phase === "Results") {
      renderResults();
    }
    updatePhaseNav();
  });

  document.querySelectorAll(".help-chip").forEach((chip) => {
    chip.addEventListener("click", () => openFaqModal());
  });
}

async function main() {
  await initI18n();
  setupHandlers();
  await refreshWithUiErrorHandling();
  startRefreshScheduler();
}

main();

function updateLanguageButtons() {
  document.querySelectorAll(".lang-button").forEach((btn) => {
    btn.textContent = "🌐";
    btn.title = t("lang.label");
    btn.setAttribute("aria-label", t("lang.label"));
  });
}

function setupLanguageSwitchers() {
  const switches = document.querySelectorAll(".lang-switch");
  const closeAll = () =>
    switches.forEach((wrap) => wrap.querySelector(".lang-menu")?.classList.add("hidden"));

  switches.forEach((wrap) => {
    const btn = wrap.querySelector(".lang-button");
    const menu = wrap.querySelector(".lang-menu");
    if (!btn || !menu) return;
    btn.addEventListener("click", (e) => {
      e.preventDefault();
      const isHidden = menu.classList.contains("hidden");
      closeAll();
      if (isHidden) menu.classList.remove("hidden");
    });
    menu.querySelectorAll("[data-lang]").forEach((item) =>
      item.addEventListener("click", () => {
        const lang = item.dataset.lang;
        if (lang) setLanguage(lang);
        closeAll();
      }),
    );
  });

  document.addEventListener("click", (e) => {
    if (!e.target.closest(".lang-switch")) closeAll();
  });

  updateLanguageButtons();
}

function markdownToHtml(md) {
  const lines = md.trim().split(/\r?\n/);
  const html = [];
  let inList = false;
  let inParagraph = false;

  const escapeHtml = (text) =>
    text
      .replace(/&/g, "&")
      .replace(/</g, "&lt;")
      .replace(/>/g, "&gt;");

  const formatInline = (text) =>
    escapeHtml(text)
      .replace(/\*\*(.+?)\*\*/g, "<strong>$1</strong>")
      .replace(/`([^`]+)`/g, "<code>$1</code>");

  const closeParagraph = () => {
    if (inParagraph) {
      html.push("</p>");
      inParagraph = false;
    }
  };

  const closeList = () => {
    if (inList) {
      html.push("</ul>");
      inList = false;
    }
  };

  lines.forEach((rawLine) => {
    const line = rawLine.trimEnd();
    const trimmed = line.trim();
    if (!trimmed) {
      closeParagraph();
      closeList();
      return;
    }

    if (/^-{5,}$/.test(trimmed)) {
      closeParagraph();
      closeList();
      html.push('<hr class="faq-divider" />');
      return;
    }

    const heading = trimmed.match(/^(#{1,3})\s+(.*)$/);
    if (heading) {
      closeParagraph();
      closeList();
      const level = heading[1].length;
      const tag = level === 1 ? "h2" : level === 2 ? "h3" : "h4";
      html.push(`<${tag}>${formatInline(heading[2].trim())}</${tag}>`);
      return;
    }

    if (/^[*-]\s+/.test(trimmed)) {
      closeParagraph();
      if (!inList) {
        html.push("<ul>");
        inList = true;
      }
      const text = trimmed.replace(/^[*-]\s+/, "");
      html.push(`<li>${formatInline(text)}</li>`);
      return;
    }

    if (!inParagraph) {
      html.push("<p>");
      inParagraph = true;
    }
    html.push(formatInline(trimmed));
  });

  closeParagraph();
  closeList();
  return html.join("\n");
}

function openFaqModal() {
  const overlay = document.createElement("div");
  overlay.className = "edit-modal";
  const panel = document.createElement("div");
  panel.className = "edit-panel faq-panel";
  panel.innerHTML = `
    <div class="edit-header">
      <h3>${t("help.title")}</h3>
      <button class="lightbox-close" aria-label="${t("modal.close")}">x</button>
    </div>
    <div class="edit-body">
      <div class="faq-list faq-content"></div>
    </div>
  `;

  const list = panel.querySelector(".faq-list");
  const lang = getLanguage();
  const md = faqMarkdown[lang] ?? faqMarkdown.en;
  list.innerHTML = markdownToHtml(md);

  const close = () => overlay.remove();
  overlay.addEventListener("click", (e) => {
    if (e.target.classList.contains("edit-modal") || e.target.classList.contains("lightbox-close")) close();
  });

  overlay.appendChild(panel);
  document.body.appendChild(overlay);
}