background.js

chrome.runtime.onInstalled.addListener(async () => {
  await chrome.sidePanel.setPanelBehavior({ openPanelOnActionClick: true });
});

function isLeetCodeProblemUrl(url) {
  if (!url) return false;
  try {
    const u = new URL(url);
    return (
      (u.hostname === "leetcode.com" || u.hostname === "www.leetcode.com") &&
      u.pathname.startsWith("/problems/")
    );
  } catch {
    return false;
  }
}

function normalizeTitle(tabTitle) {
  if (!tabTitle) return "Untitled";
  return tabTitle.replace(" - LeetCode", "").trim();
}

async function broadcast(type, payload) {
  // Persist so side panel can load it anytime
  if (type === "LC_META") await chrome.storage.local.set({ lastLcMeta: payload });
  if (type === "LC_PROBLEM_TEXT") await chrome.storage.local.set({ lastLcProblemText: payload });

  // Best-effort push to any open views (side panel). If none are open, no problem.
  try {
    chrome.runtime.sendMessage({ type, payload });
  } catch {
    // ignore
  }
}

// Fallback detection from tab URL/title (works even if content script fails)
chrome.tabs.onUpdated.addListener(async (tabId, changeInfo, tab) => {
  if (changeInfo.status !== "complete" && !changeInfo.url) return;

  const url = tab.url || changeInfo.url;
  if (!isLeetCodeProblemUrl(url)) return;

  const meta = { title: normalizeTitle(tab.title), url };
  await broadcast("LC_META", meta);
});

// Content script messages (for description/constraints)
chrome.runtime.onMessage.addListener((msg) => {
  if (msg?.type === "LC_META") broadcast("LC_META", msg.payload);
  if (msg?.type === "LC_PROBLEM_TEXT") broadcast("LC_PROBLEM_TEXT", msg.payload);
});