const statusEl = document.getElementById("status");
const btnSelection = document.getElementById("translateSelection");
const btnPage = document.getElementById("translatePage");
const btnRestore = document.getElementById("restorePage");
const btnOptions = document.getElementById("openOptions");

function setStatus(text, type = "info") {
  statusEl.textContent = text || "";
  statusEl.dataset.type = type;
}

function setButtonBusy(button, busy, busyText) {
  if (!button) {
    return;
  }
  if (!button.dataset.label) {
    button.dataset.label = button.textContent;
  }
  button.disabled = busy;
  button.textContent = busy ? busyText : button.dataset.label;
}

function setAllButtonsDisabled(disabled) {
  btnSelection.disabled = disabled;
  btnPage.disabled = disabled;
  btnRestore.disabled = disabled;
  btnOptions.disabled = disabled;
}

async function getActiveTabId() {
  const [tab] = await chrome.tabs.query({ active: true, currentWindow: true });
  if (!tab?.id) {
    throw new Error("未找到当前标签页");
  }
  return tab.id;
}

async function sendAction(action) {
  const tabId = await getActiveTabId();
  return new Promise((resolve, reject) => {
    chrome.tabs.sendMessage(tabId, { action }, (response) => {
      if (chrome.runtime.lastError) {
        reject(new Error("当前页面不支持此操作"));
        return;
      }
      if (response?.ok === false) {
        reject(new Error(response.error || "操作失败"));
        return;
      }
      resolve();
    });
  });
}

async function translateSelectionInTab() {
  const tabId = await getActiveTabId();
  return new Promise((resolve, reject) => {
    chrome.runtime.sendMessage({ action: "translateSelectionInTab", tabId }, (response) => {
      if (chrome.runtime.lastError) {
        reject(new Error(chrome.runtime.lastError.message));
        return;
      }
      if (!response?.ok) {
        reject(new Error(response?.error || "翻译失败"));
        return;
      }
      resolve({
        text: response.text || "",
        shown: !!response.shown
      });
    });
  });
}

async function runAction(button, busyText, action) {
  setStatus("");
  setAllButtonsDisabled(true);
  setButtonBusy(button, true, busyText);

  try {
    const result = await action();
    return result;
  } finally {
    setButtonBusy(button, false, busyText);
    setAllButtonsDisabled(false);
  }
}

btnOptions.addEventListener("click", () => {
  chrome.runtime.openOptionsPage();
  window.close();
});

btnSelection.addEventListener("click", async () => {
  try {
    const result = await runAction(btnSelection, "翻译中...", translateSelectionInTab);
    if (!result.shown && result.text) {
      alert(result.text);
    }
    setStatus("翻译完成", "success");
    setTimeout(() => window.close(), 120);
  } catch (err) {
    setStatus(err.message || "翻译失败", "error");
  }
});

btnPage.addEventListener("click", async () => {
  try {
    await runAction(btnPage, "启动中...", () => sendAction("translatePage"));
    setStatus("已开启随滚动翻译", "success");
    setTimeout(() => window.close(), 120);
  } catch (err) {
    setStatus(err.message || "操作失败", "error");
  }
});

btnRestore.addEventListener("click", async () => {
  try {
    await runAction(btnRestore, "恢复中...", () => sendAction("restorePage"));
    setStatus("已恢复原文", "success");
    setTimeout(() => window.close(), 120);
  } catch (err) {
    setStatus(err.message || "操作失败", "error");
  }
});