const $ = sel => document.querySelector(sel);

const inputEl = $("#input");
const outputEl = $("#output");
const schemeEl = $("#scheme");
const dialectEl = $("#dialect");
const untVersionEl = $("#unt-version");
const btnDerive = $("#btn-derive");
const btnCopy = $("#btn-copy");
let lastScheme = schemeEl.value;
let lastDialect = dialectEl.value;

function setBusy(busy) {
  btnDerive.disabled = busy;
  btnCopy.disabled = busy;
  schemeEl.disabled = busy;
  dialectEl.disabled = busy;
  untVersionEl.disabled = busy;
}

function syncSchemeUI() {
  // 选择了方言推导时，隐藏 unt 过往版本选项
  if (dialectEl.value) {
    untVersionEl.style.display = "none";
    return;
  }
  // 只有 unt_legacy 需要版本选项
  if (schemeEl.value === "unt_legacy") {
    untVersionEl.style.display = "";
  } else {
    untVersionEl.style.display = "none";
  }
}

schemeEl.addEventListener("change", syncSchemeUI);
dialectEl.addEventListener("change", syncSchemeUI);
syncSchemeUI();

function buildOptionsForScheme() {
  if (dialectEl.value) return undefined;
  if (schemeEl.value !== "unt_legacy") return undefined;
  // 这些字符串需要与 tshet-uinh-examples/unt_legacy 方案里「版本」选项的文案匹配
  const v = untVersionEl.value;
  const 版本 =
    v === "2020J"
      ? "2020：切韻擬音 J（原版）"
      : v === "2023P"
        ? "2023：切韻通俗擬音"
        : "2022：切韻擬音 L";
  return { 版本 };
}

// 如果用户直接用文件方式打开（file://），API 将不可用
if (location.protocol === "file:") {
  setBusy(true);
  outputEl.textContent = "检测到你是直接打开了 HTML 文件（file://）。请用后端服务启动后访问 http://127.0.0.1:8000/ 再推导。";
}

function escapeHtml(str) {
  return str
    .replaceAll("&", "&")
    .replaceAll("<", "&lt;")
    .replaceAll(">", "&gt;")
    .replaceAll('"', "&quot;")
    .replaceAll("'", "&#039;");
}

function renderTokens(tokens) {
  const parts = [];
  for (const t of tokens) {
    if (t.type === "raw") {
      parts.push(escapeHtml(t.text || ""));
    } else if (t.type === "annotated") {
      const ch = escapeHtml(t.ch || "");
      const rt = escapeHtml(t.pron || "");
      if (lastScheme === "tupa_high_tang") {
        // 对照模式：贴近原站“字(切韵拼音 /IPA/)”的展示风格
        parts.push(`${ch}(${rt})`);
      } else {
        parts.push(`<ruby><rb>${ch}</rb><rt>${rt}</rt></ruby>`);
      }
    }
  }
  outputEl.innerHTML = parts.join("");
}

function romanizationText(tokens) {
  // 导出：单方案输出拼音序列；对照模式输出与屏幕一致的“字(… )”文本
  if (lastScheme === "tupa_high_tang") {
    let out = "";
    for (const t of tokens) {
      if (t.type === "raw") out += t.text || "";
      else if (t.type === "annotated") out += `${t.ch || ""}(${t.pron || ""})`;
    }
    return out;
  }

  let out = "";
  for (const t of tokens) {
    if (t.type === "raw") {
      out += (t.text || "").replace(/[^\n]+/g, m => m.replaceAll(/[^\n]/g, "")); // 仅保留换行
    } else if (t.type === "annotated") {
      const s = (t.pron || "").trim();
      if (!s) continue;
      if (out && !out.endsWith("\n") && !out.endsWith(" ")) out += " ";
      out += s;
    }
  }
  return out.trim();
}

let lastTokens = [];

btnDerive.addEventListener("click", async () => {
  setBusy(true);
  outputEl.textContent = "推导中…";
  try {
    lastScheme = schemeEl.value;
    lastDialect = dialectEl.value;
    const resp = await fetch("/api/derive", {
      method: "POST",
      headers: { "Content-Type": "application/json" },
      body: JSON.stringify({
        text: inputEl.value,
        scheme: dialectEl.value || schemeEl.value,
        options: buildOptionsForScheme(),
      }),
    });
    if (!resp.ok) throw new Error(await resp.text());
    const data = await resp.json();
    lastTokens = data.tokens || [];
    renderTokens(lastTokens);
  } catch (e) {
    outputEl.textContent = "推导失败：" + (e?.message || String(e));
  } finally {
    setBusy(false);
  }
});

btnCopy.addEventListener("click", async () => {
  try {
    const text = romanizationText(lastTokens);
    await navigator.clipboard.writeText(text);
    btnCopy.textContent = "已复制";
    setTimeout(() => (btnCopy.textContent = "复制所有结果"), 800);
  } catch (e) {
    alert("复制失败：" + (e?.message || String(e)));
  }
});

// 预置示例（截取自原站示例文章开头）
inputEl.value =
  "風煙俱淨，天山共色。";