// background.js — Service Worker: orchestration, state, tab management, message routing

importScripts('data/names.js');

const LOG_PREFIX = '[MultiPage:bg]';
const DUCK_AUTOFILL_URL = 'https://duckduckgo.com/email/settings/autofill';
const STOP_ERROR_MESSAGE = 'Flow stopped by user.';
const HUMAN_STEP_DELAY_MIN = 700;
const HUMAN_STEP_DELAY_MAX = 2200;

initializeSessionStorageAccess();

let automationWindowId = null;

async function ensureAutomationWindowId() {
  if (automationWindowId != null) {
    try {
      await chrome.windows.get(automationWindowId);
      return automationWindowId;
    } catch {
      automationWindowId = null;
    }
  }
  const registry = await getTabRegistry();
  for (const entry of Object.values(registry)) {
    if (entry && entry.tabId) {
      try {
        const tab = await chrome.tabs.get(entry.tabId);
        automationWindowId = tab.windowId;
        return automationWindowId;
      } catch {}
    }
  }
  const win = await chrome.windows.getLastFocused();
  automationWindowId = win.id;
  return automationWindowId;
}


// ============================================================
// State Management (chrome.storage.session + local for persistence)
// ============================================================

// Keys that should survive extension reload (saved to chrome.storage.local)
const PERSISTENT_KEYS = [
  'vpsUrl', 'customPassword', 'mailProvider',
  'tempApiUrl',
  'inbucketHost', 'inbucketMailbox', 'accounts',
  'seenCodes', 'seenInbucketMailIds',
  'duckToken',
];

const DEFAULT_STATE = {
  currentStep: 0,
  stepStatuses: {
    1: 'pending', 2: 'pending', 3: 'pending', 4: 'pending', 5: 'pending',
    6: 'pending', 7: 'pending', 8: 'pending', 9: 'pending',
  },
  oauthUrl: null,
  email: null,
  password: null,
  accounts: [], // { email, password, createdAt }
  lastEmailTimestamp: null,
  localhostUrl: null,
  flowStartTime: null,
  tabRegistry: {},
  logs: [],
  vpsUrl: '',
  customPassword: '',
  mailProvider: 'temp-api', // 'temp-api', 'qq', '163', or 'inbucket'
  tempApiUrl: '',
  inbucketHost: '',
  inbucketMailbox: '',
};

async function getState() {
  const state = await chrome.storage.session.get(null);
  return { ...DEFAULT_STATE, ...state };
}

async function initializeSessionStorageAccess() {
  try {
    if (chrome.storage?.session?.setAccessLevel) {
      await chrome.storage.session.setAccessLevel({
        accessLevel: 'TRUSTED_AND_UNTRUSTED_CONTEXTS',
      });
      console.log(LOG_PREFIX, 'Enabled storage.session for content scripts');
    }
  } catch (err) {
    console.warn(LOG_PREFIX, 'Failed to enable storage.session for content scripts:', err?.message || err);
  }

  // Restore persistent settings from chrome.storage.local into session
  try {
    const saved = await chrome.storage.local.get(PERSISTENT_KEYS);
    const toRestore = {};
    for (const key of PERSISTENT_KEYS) {
      if (saved[key] !== undefined) toRestore[key] = saved[key];
    }
    if (Object.keys(toRestore).length > 0) {
      await chrome.storage.session.set(toRestore);
      console.log(LOG_PREFIX, 'Restored persistent settings from local storage:', Object.keys(toRestore).join(', '));
    }
  } catch (err) {
    console.warn(LOG_PREFIX, 'Failed to restore persistent settings:', err?.message || err);
  }
}

async function setState(updates) {
  console.log(LOG_PREFIX, 'storage.set:', JSON.stringify(updates).slice(0, 200));
  await chrome.storage.session.set(updates);

  // Persist relevant keys to chrome.storage.local so they survive reload
  const toPersist = {};
  for (const key of PERSISTENT_KEYS) {
    if (key in updates) toPersist[key] = updates[key];
  }
  if (Object.keys(toPersist).length > 0) {
    await chrome.storage.local.set(toPersist);
  }
}

function broadcastDataUpdate(payload) {
  chrome.runtime.sendMessage({
    type: 'DATA_UPDATED',
    payload,
  }).catch(() => {});
}

async function setEmailState(email) {
  await setState({ email });
  broadcastDataUpdate({ email });
}

async function setPasswordState(password) {
  await setState({ password });
  broadcastDataUpdate({ password });
}

async function resetState() {
  console.log(LOG_PREFIX, 'Resetting all state');
  // Preserve settings and persistent data across resets
  const prev = await chrome.storage.session.get([
    'seenCodes',
    'seenInbucketMailIds',
    'accounts',
    'tabRegistry',
    'vpsUrl',
    'customPassword',
    'mailProvider',
    'inbucketHost',
    'inbucketMailbox',
  ]);

  // Also check chrome.storage.local in case session was empty (after reload)
  const local = await chrome.storage.local.get(PERSISTENT_KEYS);

  await chrome.storage.session.clear();
  await chrome.storage.session.set({
    ...DEFAULT_STATE,
    seenCodes: prev.seenCodes || local.seenCodes || [],
    seenInbucketMailIds: prev.seenInbucketMailIds || local.seenInbucketMailIds || [],
    accounts: prev.accounts || local.accounts || [],
    tabRegistry: prev.tabRegistry || {},
    vpsUrl: prev.vpsUrl || local.vpsUrl || '',
    customPassword: prev.customPassword || local.customPassword || '',
    mailProvider: prev.mailProvider || local.mailProvider || '163',
    inbucketHost: prev.inbucketHost || local.inbucketHost || '',
    inbucketMailbox: prev.inbucketMailbox || local.inbucketMailbox || '',
  });
}

/**
 * Generate a random password: 14 chars, mix of uppercase, lowercase, digits, symbols.
 */
function generatePassword() {
  const upper = 'ABCDEFGHJKLMNPQRSTUVWXYZ';
  const lower = 'abcdefghjkmnpqrstuvwxyz';
  const digits = '23456789';
  const symbols = '!@#$%&*?';
  const all = upper + lower + digits + symbols;

  // Ensure at least one of each type
  let pw = '';
  pw += upper[Math.floor(Math.random() * upper.length)];
  pw += lower[Math.floor(Math.random() * lower.length)];
  pw += digits[Math.floor(Math.random() * digits.length)];
  pw += symbols[Math.floor(Math.random() * symbols.length)];

  // Fill remaining 10 chars
  for (let i = 0; i < 10; i++) {
    pw += all[Math.floor(Math.random() * all.length)];
  }

  // Shuffle
  return pw.split('').sort(() => Math.random() - 0.5).join('');
}

// ============================================================
// Tab Registry
// ============================================================

async function getTabRegistry() {
  const state = await getState();
  return state.tabRegistry || {};
}

async function registerTab(source, tabId) {
  const registry = await getTabRegistry();
  registry[source] = { tabId, ready: true };
  await setState({ tabRegistry: registry });
  console.log(LOG_PREFIX, `Tab registered: ${source} -> ${tabId}`);
}

async function isTabAlive(source) {
  const registry = await getTabRegistry();
  const entry = registry[source];
  if (!entry) return false;
  try {
    await chrome.tabs.get(entry.tabId);
    return true;
  } catch {
    // Tab no longer exists — clean up registry
    registry[source] = null;
    await setState({ tabRegistry: registry });
    return false;
  }
}

async function getTabId(source) {
  const registry = await getTabRegistry();
  return registry[source]?.tabId || null;
}

// ============================================================
// Command Queue (for content scripts not yet ready)
// ============================================================

const pendingCommands = new Map(); // source -> { message, resolve, reject, timer }

function queueCommand(source, message, timeout = 15000) {
  return new Promise((resolve, reject) => {
    const timer = setTimeout(() => {
      pendingCommands.delete(source);
      const err = `Content script on ${source} did not respond in ${timeout / 1000}s. Try refreshing the tab and retry.`;
      console.error(LOG_PREFIX, err);
      reject(new Error(err));
    }, timeout);
    pendingCommands.set(source, { message, resolve, reject, timer });
    console.log(LOG_PREFIX, `Command queued for ${source} (waiting for ready)`);
  });
}

function flushCommand(source, tabId) {
  const pending = pendingCommands.get(source);
  if (pending) {
    clearTimeout(pending.timer);
    pendingCommands.delete(source);
    chrome.tabs.sendMessage(tabId, pending.message).then(pending.resolve).catch(pending.reject);
    console.log(LOG_PREFIX, `Flushed queued command to ${source} (tab ${tabId})`);
  }
}

function cancelPendingCommands(reason = STOP_ERROR_MESSAGE) {
  for (const [source, pending] of pendingCommands.entries()) {
    clearTimeout(pending.timer);
    pending.reject(new Error(reason));
    pendingCommands.delete(source);
    console.log(LOG_PREFIX, `Cancelled queued command for ${source}`);
  }
}

// ============================================================
// Reuse or create tab
// ============================================================

async function reuseOrCreateTab(source, url, options = {}) {
  const alive = await isTabAlive(source);
  if (alive) {
    const tabId = await getTabId(source);
    const currentTab = await chrome.tabs.get(tabId);
    const sameUrl = currentTab.url === url;
    const shouldReloadOnReuse = sameUrl && options.reloadIfSameUrl;

    const registry = await getTabRegistry();
    if (sameUrl) {
      await chrome.tabs.update(tabId, { active: true });
      console.log(LOG_PREFIX, `Reused tab ${source} (${tabId}) on same URL`);

      if (shouldReloadOnReuse) {
        if (registry[source]) registry[source].ready = false;
        await setState({ tabRegistry: registry });
        await chrome.tabs.reload(tabId);

        await new Promise((resolve) => {
          const timer = setTimeout(() => { chrome.tabs.onUpdated.removeListener(listener); resolve(); }, 30000);
          const listener = (tid, info) => {
            if (tid === tabId && info.status === 'complete') {
              chrome.tabs.onUpdated.removeListener(listener);
              clearTimeout(timer);
              resolve();
            }
          };
          chrome.tabs.onUpdated.addListener(listener);
        });
      }

      // For dynamically injected pages like the VPS panel, re-inject immediately.
      if (options.inject) {
        if (registry[source]) registry[source].ready = false;
        await setState({ tabRegistry: registry });
        if (options.injectSource) {
          await chrome.scripting.executeScript({
            target: { tabId },
            func: (injectedSource) => {
              window.__MULTIPAGE_SOURCE = injectedSource;
            },
            args: [options.injectSource],
          });
        }
        await chrome.scripting.executeScript({
          target: { tabId },
          files: options.inject,
        });
        await new Promise(r => setTimeout(r, 500));
      }

      return tabId;
    }

    // Mark as not ready BEFORE navigating — so READY signal from new page is captured correctly
    if (registry[source]) registry[source].ready = false;
    await setState({ tabRegistry: registry });

    // Navigate existing tab to new URL
    await chrome.tabs.update(tabId, { url, active: true });
    console.log(LOG_PREFIX, `Reused tab ${source} (${tabId}), navigated to ${url.slice(0, 60)}`);

    // Wait for page load complete (with 30s timeout)
    await new Promise((resolve) => {
      const timer = setTimeout(() => { chrome.tabs.onUpdated.removeListener(listener); resolve(); }, 30000);
      const listener = (tid, info) => {
        if (tid === tabId && info.status === 'complete') {
          chrome.tabs.onUpdated.removeListener(listener);
          clearTimeout(timer);
          resolve();
        }
      };
      chrome.tabs.onUpdated.addListener(listener);
    });

    // If dynamic injection needed (VPS panel), re-inject after navigation
    if (options.inject) {
      if (options.injectSource) {
        await chrome.scripting.executeScript({
          target: { tabId },
          func: (injectedSource) => {
            window.__MULTIPAGE_SOURCE = injectedSource;
          },
          args: [options.injectSource],
        });
      }
      await chrome.scripting.executeScript({
        target: { tabId },
        files: options.inject,
      });
    }

    // Wait a bit for content script to inject and send READY
    await new Promise(r => setTimeout(r, 500));

    return tabId;
  }

  // Create new tab in the automation window
  const wid = await ensureAutomationWindowId();
  const tab = await chrome.tabs.create({ url, active: true, windowId: wid });
  console.log(LOG_PREFIX, `Created new tab ${source} (${tab.id})`);

  // If dynamic injection needed (VPS panel), inject scripts after load
  if (options.inject) {
    await new Promise((resolve) => {
      const timer = setTimeout(() => { chrome.tabs.onUpdated.removeListener(listener); resolve(); }, 30000);
      const listener = (tabId, info) => {
        if (tabId === tab.id && info.status === 'complete') {
          chrome.tabs.onUpdated.removeListener(listener);
          clearTimeout(timer);
          resolve();
        }
      };
      chrome.tabs.onUpdated.addListener(listener);
    });
    if (options.injectSource) {
      await chrome.scripting.executeScript({
        target: { tabId: tab.id },
        func: (injectedSource) => {
          window.__MULTIPAGE_SOURCE = injectedSource;
        },
        args: [options.injectSource],
      });
    }
    await chrome.scripting.executeScript({
      target: { tabId: tab.id },
      files: options.inject,
    });
  }

  return tab.id;
}

// ============================================================
// Send command to content script (with readiness check)
// ============================================================

async function sendToContentScript(source, message) {
  const registry = await getTabRegistry();
  const entry = registry[source];

  if (!entry || !entry.ready) {
    console.log(LOG_PREFIX, `${source} not ready, queuing command`);
    return queueCommand(source, message);
  }

  // Verify tab is still alive
  const alive = await isTabAlive(source);
  if (!alive) {
    // Tab was closed — queue the command, it will be sent when tab is reopened
    console.log(LOG_PREFIX, `${source} tab was closed, queuing command`);
    return queueCommand(source, message);
  }

  console.log(LOG_PREFIX, `Sending to ${source} (tab ${entry.tabId}):`, message.type);
  try {
    return await chrome.tabs.sendMessage(entry.tabId, message);
  } catch (err) {
    // Handle bfcache / port closed errors by reloading the tab and retrying
    if (err?.message?.includes('back/forward cache') || err?.message?.includes('message channel is closed')) {
      console.log(LOG_PREFIX, `${source} hit bfcache error, reloading tab and retrying...`);
      try {
        await chrome.tabs.reload(entry.tabId);
        // Wait for page to reload and content script to re-inject
        await new Promise((resolve) => {
          const timer = setTimeout(() => { chrome.tabs.onUpdated.removeListener(listener); resolve(); }, 15000);
          const listener = (tid, info) => {
            if (tid === entry.tabId && info.status === 'complete') {
              chrome.tabs.onUpdated.removeListener(listener);
              clearTimeout(timer);
              resolve();
            }
          };
          chrome.tabs.onUpdated.addListener(listener);
        });
        // Mark as not ready and wait for READY signal
        const reg = await getTabRegistry();
        if (reg[source]) reg[source].ready = false;
        await setState({ tabRegistry: reg });
        // Queue the command — it'll be sent once the content script signals READY
        return queueCommand(source, message);
      } catch (retryErr) {
        throw new Error(`${source} bfcache recovery failed: ${retryErr.message}`);
      }
    }
    throw err;
  }
}

// ============================================================
// Logging
// ============================================================

async function addLog(message, level = 'info') {
  const state = await getState();
  const logs = state.logs || [];
  const entry = { message, level, timestamp: Date.now() };
  logs.push(entry);
  // Keep last 500 logs
  if (logs.length > 500) logs.splice(0, logs.length - 500);
  await setState({ logs });
  // Broadcast to side panel
  chrome.runtime.sendMessage({ type: 'LOG_ENTRY', payload: entry }).catch(() => {});
}

// ============================================================
// Step Status Management
// ============================================================

async function setStepStatus(step, status) {
  const state = await getState();
  const statuses = { ...state.stepStatuses };
  statuses[step] = status;
  await setState({ stepStatuses: statuses, currentStep: step });
  // Broadcast to side panel
  chrome.runtime.sendMessage({
    type: 'STEP_STATUS_CHANGED',
    payload: { step, status },
  }).catch(() => {});
}

function isStopError(error) {
  const message = typeof error === 'string' ? error : error?.message;
  return message === STOP_ERROR_MESSAGE;
}

function clearStopRequest() {
  stopRequested = false;
}

function throwIfStopped() {
  if (stopRequested) {
    throw new Error(STOP_ERROR_MESSAGE);
  }
}

async function sleepWithStop(ms) {
  const start = Date.now();
  while (Date.now() - start < ms) {
    throwIfStopped();
    await new Promise(r => setTimeout(r, Math.min(100, ms - (Date.now() - start))));
  }
}

async function humanStepDelay(min = HUMAN_STEP_DELAY_MIN, max = HUMAN_STEP_DELAY_MAX) {
  const duration = Math.floor(Math.random() * (max - min + 1)) + min;
  await sleepWithStop(duration);
}

// clickWithDebugger removed — Step 8 now uses content script simulateClick directly

async function broadcastStopToContentScripts() {
  const registry = await getTabRegistry();
  for (const entry of Object.values(registry)) {
    if (!entry?.tabId) continue;
    try {
      await chrome.tabs.sendMessage(entry.tabId, {
        type: 'STOP_FLOW',
        source: 'background',
        payload: {},
      });
    } catch {}
  }
}

let stopRequested = false;

// ============================================================
// Message Handler (central router)
// ============================================================

chrome.runtime.onMessage.addListener((message, sender, sendResponse) => {
  console.log(LOG_PREFIX, `Received: ${message.type} from ${message.source || 'sidepanel'}`, message);

  handleMessage(message, sender).then(response => {
    sendResponse(response);
  }).catch(err => {
    console.error(LOG_PREFIX, 'Handler error:', err);
    sendResponse({ error: err.message });
  });

  return true; // async response
});

async function handleMessage(message, sender) {
  switch (message.type) {
    case 'CONTENT_SCRIPT_READY': {
      const tabId = sender.tab?.id;
      if (tabId && message.source) {
        await registerTab(message.source, tabId);
        flushCommand(message.source, tabId);
        await addLog(`Content script ready: ${message.source} (tab ${tabId})`);
      }
      return { ok: true };
    }

    case 'LOG': {
      const { message: msg, level } = message.payload;
      await addLog(`[${message.source}] ${msg}`, level);
      return { ok: true };
    }

    case 'STEP_COMPLETE': {
      if (stopRequested) {
        await setStepStatus(message.step, 'stopped');
        notifyStepError(message.step, STOP_ERROR_MESSAGE);
        return { ok: true };
      }
      await setStepStatus(message.step, 'completed');
      await addLog(`Step ${message.step} completed`, 'ok');
      await handleStepData(message.step, message.payload);
      notifyStepComplete(message.step, message.payload);
      return { ok: true };
    }

    case 'STEP_ERROR': {
      if (isStopError(message.error)) {
        await setStepStatus(message.step, 'stopped');
        await addLog(`Step ${message.step} stopped by user`, 'warn');
        notifyStepError(message.step, message.error);
      } else {
        await setStepStatus(message.step, 'failed');
        await addLog(`Step ${message.step} failed: ${message.error}`, 'error');
        notifyStepError(message.step, message.error);
      }
      return { ok: true };
    }

    case 'GET_STATE': {
      return await getState();
    }

    case 'RESET': {
      clearStopRequest();
      await resetState();
      await addLog('Flow reset', 'info');
      return { ok: true };
    }

    case 'EXECUTE_STEP': {
      clearStopRequest();
      const step = message.payload.step;
      // Save email if provided (from side panel step 3)
      if (message.payload.email) {
        await setEmailState(message.payload.email);
      }
      await executeStep(step);
      return { ok: true };
    }

    case 'AUTO_RUN': {
      clearStopRequest();
      const totalRuns = message.payload?.totalRuns || 1;
      autoRunLoop(totalRuns);  // fire-and-forget
      return { ok: true };
    }

    case 'RESUME_AUTO_RUN': {
      clearStopRequest();
      if (message.payload.email) {
        await setEmailState(message.payload.email);
      }
      resumeAutoRun();  // fire-and-forget
      return { ok: true };
    }

    case 'SAVE_SETTING': {
      const updates = {};
      if (message.payload.vpsUrl !== undefined) updates.vpsUrl = message.payload.vpsUrl;
      if (message.payload.customPassword !== undefined) updates.customPassword = message.payload.customPassword;
      if (message.payload.mailProvider !== undefined) updates.mailProvider = message.payload.mailProvider;
      if (message.payload.tempApiUrl !== undefined) updates.tempApiUrl = message.payload.tempApiUrl;
      if (message.payload.inbucketHost !== undefined) updates.inbucketHost = message.payload.inbucketHost;
      if (message.payload.inbucketMailbox !== undefined) updates.inbucketMailbox = message.payload.inbucketMailbox;
      await setState(updates);
      return { ok: true };
    }

    // Side panel data updates
    case 'SAVE_EMAIL': {
      await setEmailState(message.payload.email);
      return { ok: true, email: message.payload.email };
    }

    case 'FETCH_DUCK_EMAIL': {
      clearStopRequest();
      const email = await fetchDuckEmail(message.payload || {});
      return { ok: true, email };
    }

    case 'STOP_FLOW': {
      await requestStop();
      return { ok: true };
    }

    default:
      console.warn(LOG_PREFIX, `Unknown message type: ${message.type}`);
      return { error: `Unknown message type: ${message.type}` };
  }
}

// ============================================================
// Step Data Handlers
// ============================================================

async function handleStepData(step, payload) {
  switch (step) {
    case 1:
      if (payload.oauthUrl) {
        await setState({ oauthUrl: payload.oauthUrl });
        broadcastDataUpdate({ oauthUrl: payload.oauthUrl });
      }
      break;
    case 3:
      if (payload.email) await setEmailState(payload.email);
      break;
    case 4:
      if (payload.emailTimestamp) await setState({ lastEmailTimestamp: payload.emailTimestamp });
      break;
    case 8:
      if (payload.localhostUrl) {
        await setState({ localhostUrl: payload.localhostUrl });
        broadcastDataUpdate({ localhostUrl: payload.localhostUrl });
      }
      break;
  }
}

// ============================================================
// Step Completion Waiting
// ============================================================

// Map of step -> { resolve, reject } for waiting on step completion
const stepWaiters = new Map();
let resumeWaiter = null;

function waitForStepComplete(step, timeoutMs = 120000) {
  return new Promise((resolve, reject) => {
    throwIfStopped();
    const timer = setTimeout(() => {
      stepWaiters.delete(step);
      reject(new Error(`Step ${step} timed out after ${timeoutMs / 1000}s`));
    }, timeoutMs);

    stepWaiters.set(step, {
      resolve: (data) => { clearTimeout(timer); stepWaiters.delete(step); resolve(data); },
      reject: (err) => { clearTimeout(timer); stepWaiters.delete(step); reject(err); },
    });
  });
}

function notifyStepComplete(step, payload) {
  const waiter = stepWaiters.get(step);
  if (waiter) waiter.resolve(payload);
}

function notifyStepError(step, error) {
  const waiter = stepWaiters.get(step);
  if (waiter) waiter.reject(new Error(error));
}

async function markRunningStepsStopped() {
  const state = await getState();
  const runningSteps = Object.entries(state.stepStatuses || {})
    .filter(([, status]) => status === 'running')
    .map(([step]) => Number(step));

  for (const step of runningSteps) {
    await setStepStatus(step, 'stopped');
  }
}

async function requestStop() {
  if (stopRequested) return;

  stopRequested = true;
  cancelPendingCommands();
  if (webNavListener) {
    chrome.webNavigation.onBeforeNavigate.removeListener(webNavListener);
    webNavListener = null;
  }

  await addLog('Stop requested. Cancelling current operations...', 'warn');
  await broadcastStopToContentScripts();

  for (const waiter of stepWaiters.values()) {
    waiter.reject(new Error(STOP_ERROR_MESSAGE));
  }
  stepWaiters.clear();

  if (resumeWaiter) {
    resumeWaiter.reject(new Error(STOP_ERROR_MESSAGE));
    resumeWaiter = null;
  }

  await markRunningStepsStopped();
  autoRunActive = false;
  await setState({ autoRunning: false });
  chrome.runtime.sendMessage({
    type: 'AUTO_RUN_STATUS',
    payload: { phase: 'stopped', currentRun: autoRunCurrentRun, totalRuns: autoRunTotalRuns },
  }).catch(() => {});
}

// ============================================================
// Step Execution
// ============================================================

async function executeStep(step) {
  console.log(LOG_PREFIX, `Executing step ${step}`);
  throwIfStopped();
  await setStepStatus(step, 'running');
  await addLog(`Step ${step} started`);
  await humanStepDelay();

  const state = await getState();

  // Set flow start time on first step
  if (step === 1 && !state.flowStartTime) {
    await setState({ flowStartTime: Date.now() });
  }

  try {
    switch (step) {
      case 1: await executeStep1(state); break;
      case 2: await executeStep2(state); break;
      case 3: await executeStep3(state); break;
      case 4: await executeStep4(state); break;
      case 5: await executeStep5(state); break;
      case 6: await executeStep6(state); break;
      case 7: await executeStep7(state); break;
      case 8: await executeStep8(state); break;
      case 9: await executeStep9(state); break;
      default:
        throw new Error(`Unknown step: ${step}`);
    }
  } catch (err) {
    if (isStopError(err)) {
      await setStepStatus(step, 'stopped');
      await addLog(`Step ${step} stopped by user`, 'warn');
      throw err;
    }
    await setStepStatus(step, 'failed');
    await addLog(`Step ${step} failed: ${err.message}`, 'error');
    throw err;
  }
}

/**
 * Execute a step and wait for it to complete before returning.
 * @param {number} step
 * @param {number} delayAfter - ms to wait after completion (for page transitions)
 */
async function executeStepAndWait(step, delayAfter = 2000) {
  throwIfStopped();
  const promise = waitForStepComplete(step, 120000);
  await executeStep(step);
  await promise;
  // Extra delay for page transitions / DOM updates
  if (delayAfter > 0) {
    await sleepWithStop(delayAfter + Math.floor(Math.random() * 1200));
  }
}

async function fetchDuckEmail(options = {}) {
  throwIfStopped();

  // Try API-based generation first (no tab needed)
  const state = await getState();
  let token = state.duckToken;

  if (token) {
    try {
      const email = await generateDuckEmailViaApi(token);
      await setEmailState(email);
      await addLog(`Duck Mail: Generated ${email} (via API, no tab)`, 'ok');
      return email;
    } catch (err) {
      await addLog(`Duck Mail: API generation failed: ${err.message}, falling back to page...`, 'warn');
      // Token may be expired, clear it so we re-extract
      token = null;
      await setState({ duckToken: null });
    }
  }

  // Fallback: open page, extract token for future use, then generate
  await addLog('Duck Mail: Opening page to extract token...');
  await reuseOrCreateTab('duck-mail', DUCK_AUTOFILL_URL);

  // Try to extract and save the access token
  try {
    const tokenResult = await sendToContentScript('duck-mail', {
      type: 'EXTRACT_DUCK_TOKEN',
      source: 'background',
      payload: {},
    });
    if (tokenResult?.token) {
      token = tokenResult.token;
      await setState({ duckToken: token });
      await addLog(`Duck Mail: Token saved for ${tokenResult.username}, future runs won't need page`, 'ok');

      // Now use API to generate
      const email = await generateDuckEmailViaApi(token);
      await setEmailState(email);
      await addLog(`Duck Mail: Generated ${email} (via API)`, 'ok');
      return email;
    }
  } catch (err) {
    await addLog(`Duck Mail: Token extraction failed: ${err.message}, using page method`, 'warn');
  }

  // Final fallback: use the old page-based method
  const result = await sendToContentScript('duck-mail', {
    type: 'FETCH_DUCK_EMAIL',
    source: 'background',
    payload: { generateNew: true },
  });

  if (result?.error) throw new Error(result.error);
  if (!result?.email) throw new Error('Duck email not returned.');

  await setEmailState(result.email);
  await addLog(`Duck Mail: ${result.generated ? 'Generated' : 'Loaded'} ${result.email} (via page)`, 'ok');
  return result.email;
}

async function generateDuckEmailViaApi(token) {
  const resp = await fetch('https://quack.duckduckgo.com/api/email/addresses', {
    method: 'POST',
    headers: {
      'Authorization': `Bearer ${token}`,
      'Content-Type': 'application/json',
    },
  });
  if (!resp.ok) {
    throw new Error(`DuckDuckGo API returned ${resp.status}`);
  }
  const data = await resp.json();
  // Response: { address: "random-words" }
  const address = data?.address;
  if (!address) throw new Error('No address in API response');
  return `${address}@duck.com`;
}

// ============================================================
// Auto Run Flow
// ============================================================

let autoRunActive = false;
let autoRunCurrentRun = 0;
let autoRunTotalRuns = 1;

// Outer loop: runs the full flow N times
async function autoRunLoop(totalRuns) {
  if (autoRunActive) {
    await addLog('Auto run already in progress', 'warn');
    return;
  }

  clearStopRequest();
  autoRunActive = true;
  autoRunTotalRuns = totalRuns;
  let successCount = 0;
  let failCount = 0;
  await setState({ autoRunning: true });

  for (let run = 1; run <= totalRuns; run++) {
    autoRunCurrentRun = run;

    // Reset everything at the start of each run (keep VPS/mail settings)
    const prevState = await getState();
    const keepSettings = {
      vpsUrl: prevState.vpsUrl,
      mailProvider: prevState.mailProvider,
      tempApiUrl: prevState.tempApiUrl,
      inbucketHost: prevState.inbucketHost,
      inbucketMailbox: prevState.inbucketMailbox,
      duckToken: prevState.duckToken,
      autoRunning: true,
    };
    await resetState();
    await setState(keepSettings);
    // Tell side panel to reset all UI
    chrome.runtime.sendMessage({ type: 'AUTO_RUN_RESET' }).catch(() => {});
    await sleepWithStop(500);

    await addLog(`=== Auto Run ${run}/${totalRuns} — Phase 1: Get OAuth link & open signup ===`, 'info');
    const status = (phase) => ({ type: 'AUTO_RUN_STATUS', payload: { phase, currentRun: run, totalRuns, successCount } });

    try {
      throwIfStopped();
      chrome.runtime.sendMessage(status('running')).catch(() => {});

      await executeStepAndWait(1, 2000);
      await executeStepAndWait(2, 2000);

      const duckEmail = await fetchDuckEmail({ generateNew: true });
      await addLog(`=== Run ${run}/${totalRuns} — Duck email ready: ${duckEmail} ===`, 'ok');

      await addLog(`=== Run ${run}/${totalRuns} — Phase 2: Register, verify, login, complete ===`, 'info');
      chrome.runtime.sendMessage(status('running')).catch(() => {});

      const signupTabId = await getTabId('signup-page');
      if (signupTabId) {
        await chrome.tabs.update(signupTabId, { active: true });
      }

      await executeStepAndWait(3, 3000);
      await executeStepAndWait(4, 2000);
      await executeStepAndWait(5, 3000);
      await executeStepAndWait(6, 3000);

      // After login, check if page landed on add-phone again (not normal after step 5)
      const phoneCheckTabId = await getTabId('signup-page');
      if (phoneCheckTabId) {
        try {
          const phoneTab = await chrome.tabs.get(phoneCheckTabId);
          if (phoneTab.url && (phoneTab.url.includes('add-phone') || phoneTab.url.includes('/phone'))) {
            throw new Error('PHONE_VERIFY_REQUIRED');
          }
        } catch (e) {
          if (e.message === 'PHONE_VERIFY_REQUIRED') throw e;
        }
      }

      await executeStepAndWait(7, 2000);
      await executeStepAndWait(8, 2000);
      await executeStepAndWait(9, 1000);

      successCount++;
      await addLog(`=== Run ${run}/${totalRuns} COMPLETE! (${successCount} succeeded, ${failCount} failed) ===`, 'ok');

    } catch (err) {
      if (isStopError(err)) {
        await addLog(`Run ${run}/${totalRuns} stopped by user`, 'warn');
        chrome.runtime.sendMessage(status('stopped')).catch(() => {});
        break; // Only stop on explicit user stop
      } else {
        failCount++;
        if (err.message === 'PHONE_VERIFY_REQUIRED') {
          await addLog(`Run ${run}/${totalRuns} failed: Phone verification required — sleeping 30s before next run (${successCount} succeeded, ${failCount} failed)`, 'error');
          await sleepWithStop(30000);
        } else {
          await addLog(`Run ${run}/${totalRuns} failed: ${err.message} (${successCount} succeeded, ${failCount} failed)`, 'error');
        }
        await addLog(`Skipping to next run...`, 'warn');
        continue;
      }
    }
  }

  const attempted = autoRunCurrentRun;
  if (stopRequested) {
    await addLog(`=== Stopped after ${Math.max(0, attempted - 1)}/${autoRunTotalRuns} runs — ${successCount} succeeded, ${failCount} failed ===`, 'warn');
    chrome.runtime.sendMessage({ type: 'AUTO_RUN_STATUS', payload: { phase: 'stopped', currentRun: attempted, totalRuns: autoRunTotalRuns, successCount, failCount } }).catch(() => {});
  } else {
    await addLog(`=== All ${autoRunTotalRuns} runs finished — ${successCount} succeeded, ${failCount} failed ===`, successCount > 0 ? 'ok' : 'warn');
    chrome.runtime.sendMessage({ type: 'AUTO_RUN_STATUS', payload: { phase: 'complete', currentRun: attempted, totalRuns: autoRunTotalRuns, successCount, failCount } }).catch(() => {});
  }
  autoRunActive = false;
  await setState({ autoRunning: false });
  clearStopRequest();
}

function waitForResume() {
  return new Promise((resolve, reject) => {
    throwIfStopped();
    resumeWaiter = { resolve, reject };
  });
}

async function resumeAutoRun() {
  throwIfStopped();
  const state = await getState();
  if (!state.email) {
    await addLog('Cannot resume: no email address. Paste email in Side Panel first.', 'error');
    return;
  }
  if (resumeWaiter) {
    resumeWaiter.resolve();
    resumeWaiter = null;
  }
}

// ============================================================
// Step 1: Get OAuth Link (via vps-panel.js)
// ============================================================

async function executeStep1(state) {
  if (!state.vpsUrl) {
    throw new Error('No VPS URL configured. Enter VPS address in Side Panel first.');
  }
  await addLog(`Step 1: Opening VPS panel...`);
  await reuseOrCreateTab('vps-panel', state.vpsUrl, {
    inject: ['content/utils.js', 'content/vps-panel.js'],
    reloadIfSameUrl: true,
  });

  await sendToContentScript('vps-panel', {
    type: 'EXECUTE_STEP',
    step: 1,
    source: 'background',
    payload: {},
  });
}

// ============================================================
// Step 2: Open Signup Page (Background opens tab, signup-page.js clicks Register)
// ============================================================

async function executeStep2(state) {
  if (!state.oauthUrl) {
    throw new Error('No OAuth URL. Complete step 1 first.');
  }
  await addLog(`Step 2: Opening auth URL...`);
  await reuseOrCreateTab('signup-page', state.oauthUrl);

  await sendToContentScript('signup-page', {
    type: 'EXECUTE_STEP',
    step: 2,
    source: 'background',
    payload: {},
  });
}

// ============================================================
// Step 3: Fill Email & Password (via signup-page.js)
// ============================================================

async function executeStep3(state) {
  if (!state.email) {
    throw new Error('No email address. Paste email in Side Panel first.');
  }

  const password = state.customPassword || generatePassword();
  await setPasswordState(password);

  // Save account record
  const accounts = state.accounts || [];
  accounts.push({ email: state.email, password, createdAt: new Date().toISOString() });
  await setState({ accounts });

  await addLog(
    `Step 3: Filling email ${state.email}, password ${state.customPassword ? 'customized' : 'generated'} (${password.length} chars)`
  );
  await sendToContentScript('signup-page', {
    type: 'EXECUTE_STEP',
    step: 3,
    source: 'background',
    payload: { email: state.email, password },
  });
}

// ============================================================
// Step 4: Get Signup Verification Code (qq-mail.js polls, then fills in signup-page.js)
// ============================================================

async function getMailConfig(state) {
  const provider = state.mailProvider || 'temp-api';
  if (provider === 'temp-api') {
    let rawUrl = (state.tempApiUrl || '').trim();
    // Fallback: read directly from chrome.storage.local in case session is stale
    if (!rawUrl) {
      const local = await chrome.storage.local.get('tempApiUrl');
      rawUrl = (local.tempApiUrl || '').trim();
    }
    if (!rawUrl) {
      return { error: 'Temp Email API URL is empty. Please paste the full URL with JWT in Side Panel.' };
    }
    // Extract base origin and JWT from the URL (e.g. https://host/?jwt=xxx)
    let apiOrigin, jwt;
    try {
      const parsed = new URL(rawUrl);
      apiOrigin = parsed.origin;
      jwt = parsed.searchParams.get('jwt');
    } catch {
      return { error: 'Temp Email API URL is invalid.' };
    }
    if (!jwt) {
      return { error: 'Temp Email API URL has no jwt parameter.' };
    }
    return {
      source: 'temp-api',
      apiOrigin,
      jwt,
      label: 'Temp Email API',
      useFetch: true, // signal that this provider uses fetch, not a tab
    };
  }
  if (provider === '163') {
    return { source: 'mail-163', url: 'https://mail.163.com/js6/main.jsp?df=mail163_letter#module=mbox.ListModule%7C%7B%22fid%22%3A1%2C%22order%22%3A%22date%22%2C%22desc%22%3Atrue%7D', label: '163 Mail' };
  }
  if (provider === 'inbucket') {
    const host = normalizeInbucketOrigin(state.inbucketHost);
    const mailbox = (state.inbucketMailbox || '').trim();
    if (!host) {
      return { error: 'Inbucket host is empty or invalid.' };
    }
    if (!mailbox) {
      return { error: 'Inbucket mailbox name is empty.' };
    }
    return {
      source: 'inbucket-mail',
      url: `${host}/m/${encodeURIComponent(mailbox)}/`,
      label: `Inbucket Mailbox (${mailbox})`,
      navigateOnReuse: true,
      inject: ['content/utils.js', 'content/inbucket-mail.js'],
      injectSource: 'inbucket-mail',
    };
  }
  return { source: 'qq-mail', url: 'https://wx.mail.qq.com/', label: 'QQ Mail' };
}

function normalizeInbucketOrigin(rawValue) {
  const value = (rawValue || '').trim();
  if (!value) return '';

  const candidate = /^[a-zA-Z][a-zA-Z\d+\-.]*:\/\//.test(value) ? value : `https://${value}`;

  try {
    const parsed = new URL(candidate);
    return parsed.origin;
  } catch {
    return '';
  }
}

// ============================================================
// Temp Email API: fetch-based polling (no tab needed)
// ============================================================

function extractVerificationCodeFromText(text) {
  // Pattern 1: Chinese format "代码为 370794" or "验证码...370794"
  const matchCn = text.match(/(?:代码为|验证码[^0-9]*?)[\s：:]*(\d{6})/);
  if (matchCn) return matchCn[1];
  // Pattern 2: English format "code is 370794" or "code: 370794"
  const matchEn = text.match(/code[:\s]+is[:\s]+(\d{6})|code[:\s]+(\d{6})/i);
  if (matchEn) return matchEn[1] || matchEn[2];
  // Pattern 3: standalone 6-digit number
  const match6 = text.match(/\b(\d{6})\b/);
  if (match6) return match6[1];
  return null;
}

function decodeMimeWord(encoded) {
  // Decode =?charset?encoding?text?= (RFC 2047)
  return encoded.replace(/=\?([^?]+)\?(B|Q)\?([^?]*)\?=/gi, (_, charset, enc, text) => {
    if (enc.toUpperCase() === 'B') {
      // Base64
      try { return atob(text); } catch { return text; }
    }
    // Quoted-Printable
    return text.replace(/_/g, ' ').replace(/=([0-9A-Fa-f]{2})/g, (__, hex) =>
      String.fromCharCode(parseInt(hex, 16))
    );
  });
}

function decodeUtf8Bytes(str) {
  // If the decoded string contains raw UTF-8 bytes, decode them
  try { return decodeURIComponent(escape(str)); } catch { return str; }
}

function extractSubjectFromRaw(raw) {
  // Extract Subject header (may span multiple lines with folding)
  const match = raw.match(/^Subject:\s*([\s\S]*?)(?=\r?\n[^\s]|\r?\n\r?\n)/mi);
  if (!match) return '';
  // Unfold continuation lines and decode MIME words
  const unfolded = match[1].replace(/\r?\n\s+/g, ' ').trim();
  return decodeUtf8Bytes(decodeMimeWord(unfolded));
}

function extractFromHeader(raw) {
  const match = raw.match(/^From:\s*([\s\S]*?)(?=\r?\n[^\s]|\r?\n\r?\n)/mi);
  if (!match) return '';
  return match[1].replace(/\r?\n\s+/g, ' ').trim().toLowerCase();
}

function extractPlainTextFromRaw(raw) {
  // Try to extract the text/plain part from a multipart email
  const plainMatch = raw.match(/Content-Type:\s*text\/plain[\s\S]*?\r?\n\r?\n([\s\S]*?)(?:\r?\n--|\r?\n$)/i);
  if (plainMatch) {
    let text = plainMatch[1];
    // Decode quoted-printable
    text = text.replace(/=\r?\n/g, '');
    text = text.replace(/=([0-9A-Fa-f]{2})/g, (_, hex) => String.fromCharCode(parseInt(hex, 16)));
    try { return decodeURIComponent(escape(text)); } catch { return text; }
  }
  return raw;
}

async function pollTempEmailApi(mail, step, payload) {
  const { senderFilters, subjectFilters, maxAttempts, intervalMs, usedMailIds, usedCodes } = payload;
  const usedIdSet = new Set((usedMailIds || []).map(String));
  const usedCodeSet = new Set(usedCodes || []);

  const headers = { 'Authorization': `Bearer ${mail.jwt}` };

  for (let attempt = 1; attempt <= maxAttempts; attempt++) {
    throwIfStopped();
    await addLog(`Step ${step}: Polling Temp Email API... attempt ${attempt}/${maxAttempts}`);

    try {
      const resp = await fetch(`${mail.apiOrigin}/api/mails?limit=10&offset=0`, { headers });
      if (!resp.ok) throw new Error(`API returned ${resp.status}`);
      const data = await resp.json();
      const mails = data.results || [];

      for (const m of mails) {
        if (usedIdSet.has(String(m.id))) continue;

        const raw = m.raw || '';
        const source = (m.source || '').toLowerCase();
        const fromHeader = extractFromHeader(raw);
        const subject = extractSubjectFromRaw(raw).toLowerCase();
        const plainText = extractPlainTextFromRaw(raw);

        // Match against both envelope sender and From header
        const senderMatch = senderFilters.some(f => {
          const fl = f.toLowerCase();
          return source.includes(fl) || fromHeader.includes(fl);
        });
        const subjectMatch = subjectFilters.some(f => subject.includes(f.toLowerCase()));

        if (senderMatch || subjectMatch) {
          const code = extractVerificationCodeFromText(subject + ' ' + plainText);
          if (code) {
            if (usedCodeSet.has(code)) {
              console.log(LOG_PREFIX, `Step ${step}: Skipping already-used code ${code} (id: ${m.id})`);
              continue;
            }
            await addLog(`Step ${step}: Code found from API: ${code} (subject: ${subject.slice(0, 40)})`, 'ok');
            return { ok: true, code, emailTimestamp: Date.now(), mailId: String(m.id) };
          }
        }
      }
    } catch (err) {
      await addLog(`Step ${step}: API fetch error: ${err.message}`, 'warn');
    }

    if (attempt < maxAttempts) {
      await sleepWithStop(intervalMs);
    }
  }

  throw new Error(
    `No matching email found via Temp Email API after ${(maxAttempts * intervalMs / 1000).toFixed(0)}s. ` +
    'Email may be delayed.'
  );
}

async function clickResendOnSignupPage(step) {
  const signupTabId = await getTabId('signup-page');
  if (!signupTabId) return;

  await chrome.tabs.update(signupTabId, { active: true });
  await sleepWithStop(500);

  try {
    await sendToContentScript('signup-page', {
      type: 'CLICK_RESEND_EMAIL',
      step,
      source: 'background',
    });
  } catch (err) {
    await addLog(`Step ${step}: Resend click skipped: ${err.message}`, 'warn');
  }
}

async function executeStep4(state) {
  // Click "重新发送电子邮件" on the signup page before polling
  await clickResendOnSignupPage(4);

  // Re-read state to ensure tempApiUrl is fresh (may have been saved after initial getState)
  const freshState = await getState();
  const mail = await getMailConfig(freshState);
  if (mail.error) throw new Error(mail.error);

  const pollPayload = {
    filterAfterTimestamp: state.flowStartTime || 0,
    senderFilters: ['openai', 'noreply', 'verify', 'auth', 'duckduckgo', 'forward'],
    subjectFilters: ['verify', 'verification', 'code', '验证', 'confirm'],
    targetEmail: state.email,
    maxAttempts: 20,
    intervalMs: 3000,
    usedMailIds: state.usedMailIds || [],
    usedCodes: state.usedCodes || [],
  };

  let result;

  if (mail.useFetch) {
    // Temp Email API: fetch directly, no tab needed
    await addLog(`Step 4: Polling ${mail.label}...`);
    result = await pollTempEmailApi(mail, 4, pollPayload);
  } else {
    await addLog(`Step 4: Opening ${mail.label}...`);
    // For mail tabs, only create if not alive — don't navigate (preserves login session)
    const alive = await isTabAlive(mail.source);
    if (alive) {
      if (mail.navigateOnReuse) {
        await reuseOrCreateTab(mail.source, mail.url, {
          inject: mail.inject,
          injectSource: mail.injectSource,
        });
      } else {
        const tabId = await getTabId(mail.source);
        await chrome.tabs.update(tabId, { active: true });
      }
    } else {
      await reuseOrCreateTab(mail.source, mail.url, {
        inject: mail.inject,
        injectSource: mail.injectSource,
      });
    }

    result = await sendToContentScript(mail.source, {
      type: 'POLL_EMAIL',
      step: 4,
      source: 'background',
      payload: pollPayload,
    });
  }

  if (result && result.error) {
    throw new Error(result.error);
  }

  if (result && result.code) {
    // Track used mail IDs and codes to avoid reusing stale ones
    const usedMailIds = [...(state.usedMailIds || [])];
    const usedCodes = [...(state.usedCodes || [])];
    if (result.mailId) usedMailIds.push(result.mailId);
    usedCodes.push(result.code);
    await setState({ lastEmailTimestamp: result.emailTimestamp, usedMailIds, usedCodes });
    await addLog(`Step 4: Got verification code: ${result.code}`);

    // Switch to signup tab and fill code
    const signupTabId = await getTabId('signup-page');
    if (signupTabId) {
      await chrome.tabs.update(signupTabId, { active: true });
      await sendToContentScript('signup-page', {
        type: 'FILL_CODE',
        step: 4,
        source: 'background',
        payload: { code: result.code },
      });
    } else {
      throw new Error('Signup page tab was closed. Cannot fill verification code.');
    }
  }
}

// ============================================================
// Step 5: Fill Name & Birthday (via signup-page.js)
// ============================================================

async function executeStep5(state) {
  const { firstName, lastName } = generateRandomName();
  const { year, month, day } = generateRandomBirthday();

  // Save birthday data to state for potential reuse on about-you page
  await setState({ birthYear: year, birthMonth: month, birthDay: day, fullName: `${firstName} ${lastName}` });

  await addLog(`Step 5: Generated name: ${firstName} ${lastName}, Birthday: ${year}-${month}-${day}`);

  await sendToContentScript('signup-page', {
    type: 'EXECUTE_STEP',
    step: 5,
    source: 'background',
    payload: { firstName, lastName, year, month, day },
  });
}

// ============================================================
// Step 6: Login ChatGPT (Background opens tab, chatgpt.js handles login)
// ============================================================

async function executeStep6(state) {
  if (!state.oauthUrl) {
    throw new Error('No OAuth URL. Complete step 1 first.');
  }
  if (!state.email) {
    throw new Error('No email. Complete step 3 first.');
  }

  await addLog(`Step 6: Opening OAuth URL for login...`);
  // Reuse the signup-page tab — navigate it to the OAuth URL
  await reuseOrCreateTab('signup-page', state.oauthUrl);

  // signup-page.js will inject (same auth.openai.com domain) and handle login
  await sendToContentScript('signup-page', {
    type: 'EXECUTE_STEP',
    step: 6,
    source: 'background',
    payload: { email: state.email, password: state.password },
  });
}

// ============================================================
// Step 7: Get Login Verification Code (qq-mail.js polls, then fills in chatgpt.js)
// ============================================================

async function executeStep7(state) {
  // Check if the page is on /about-you (birthday not filled during signup)
  // and handle it before proceeding with verification code polling
  try {
    const aboutYouResult = await sendToContentScript('signup-page', {
      type: 'HANDLE_ABOUT_YOU',
      step: 7,
      source: 'background',
      payload: {
        year: state.birthYear,
        month: state.birthMonth,
        day: state.birthDay,
        fullName: state.fullName,
      },
    });
    if (aboutYouResult && aboutYouResult.handled) {
      await addLog('Step 7: Handled about-you page, waiting for next page...', 'info');
      await sleep(3000);
    }
  } catch (e) {
    // Not on about-you page, continue normally
  }

  // Click "重新发送电子邮件" on the auth page before polling
  await clickResendOnSignupPage(7);

  const mail = await getMailConfig(state);
  if (mail.error) throw new Error(mail.error);

  // Re-read state to get latest usedMailIds/usedCodes
  const freshState = await getState();

  const pollPayload = {
    filterAfterTimestamp: freshState.lastEmailTimestamp || freshState.flowStartTime || 0,
    senderFilters: ['openai', 'noreply', 'verify', 'auth', 'chatgpt', 'duckduckgo', 'forward'],
    subjectFilters: ['verify', 'verification', 'code', '验证', 'confirm', 'login'],
    targetEmail: freshState.email,
    maxAttempts: 20,
    intervalMs: 3000,
    usedMailIds: freshState.usedMailIds || [],
    usedCodes: freshState.usedCodes || [],
  };

  let result;

  if (mail.useFetch) {
    await addLog(`Step 7: Polling ${mail.label}...`);
    result = await pollTempEmailApi(mail, 7, pollPayload);
  } else {
    await addLog(`Step 7: Opening ${mail.label}...`);
    const alive = await isTabAlive(mail.source);
    if (alive) {
      if (mail.navigateOnReuse) {
        await reuseOrCreateTab(mail.source, mail.url, {
          inject: mail.inject,
          injectSource: mail.injectSource,
        });
      } else {
        const tabId = await getTabId(mail.source);
        await chrome.tabs.update(tabId, { active: true });
      }
    } else {
      await reuseOrCreateTab(mail.source, mail.url, {
        inject: mail.inject,
        injectSource: mail.injectSource,
      });
    }

    result = await sendToContentScript(mail.source, {
      type: 'POLL_EMAIL',
      step: 7,
      source: 'background',
      payload: pollPayload,
    });
  }

  if (result && result.error) {
    throw new Error(result.error);
  }

  if (result && result.code) {
    // Track used mail IDs and codes
    const usedMailIds = [...(freshState.usedMailIds || [])];
    const usedCodes = [...(freshState.usedCodes || [])];
    if (result.mailId) usedMailIds.push(result.mailId);
    usedCodes.push(result.code);
    await setState({ usedMailIds, usedCodes });
    await addLog(`Step 7: Got login verification code: ${result.code}`);

    // Switch to signup/auth tab and fill code
    const signupTabId = await getTabId('signup-page');
    if (signupTabId) {
      await chrome.tabs.update(signupTabId, { active: true });
      await sendToContentScript('signup-page', {
        type: 'FILL_CODE',
        step: 7,
        source: 'background',
        payload: { code: result.code },
      });
    } else {
      throw new Error('Auth page tab was closed. Cannot fill verification code.');
    }
  }
}

// ============================================================
// Step 8: Complete OAuth (auto click + localhost listener)
// ============================================================

let webNavListener = null;

async function executeStep8(state) {
  if (!state.oauthUrl) {
    throw new Error('No OAuth URL. Complete step 1 first.');
  }

  // Check if the signup tab already redirected to localhost before listener setup
  const signupTabIdEarly = await getTabId('signup-page');
  if (signupTabIdEarly) {
    try {
      const tab = await chrome.tabs.get(signupTabIdEarly);
      if (tab.url && (tab.url.startsWith('http://localhost') || tab.url.startsWith('http://127.0.0.1'))) {
        await addLog(`Step 8: Localhost redirect already captured: ${tab.url}`, 'ok');
        await setState({ localhostUrl: tab.url });
        broadcastDataUpdate({ localhostUrl: tab.url });
        return;
      }
    } catch {}
  }

  await addLog('Step 8: Setting up localhost redirect listener...');

  // Register webNavigation listener (scoped to this step)
  return new Promise((resolve, reject) => {
    let resolved = false;

    const isLocalhostUrl = (url) =>
      url && (url.startsWith('http://localhost') || url.startsWith('http://127.0.0.1'));

    const cleanupListeners = () => {
      if (webNavListener) {
        chrome.webNavigation.onBeforeNavigate.removeListener(webNavListener);
        chrome.webNavigation.onCommitted.removeListener(webNavListener);
        chrome.webNavigation.onErrorOccurred.removeListener(webNavListener);
        webNavListener = null;
      }
    };

    const captureLocalhostUrl = (url) => {
      if (resolved) return;
      resolved = true;
      cleanupListeners();
      clearTimeout(timeout);
      setState({ localhostUrl: url }).then(() => {
        addLog(`Step 8: Captured localhost URL: ${url}`, 'ok');
        setStepStatus(8, 'completed');
        notifyStepComplete(8, { localhostUrl: url });
        broadcastDataUpdate({ localhostUrl: url });
        resolve();
      });
    };

    const timeout = setTimeout(() => {
      cleanupListeners();
      reject(new Error('Localhost redirect not captured after 120s. Step 8 click may have been blocked.'));
    }, 120000);

    webNavListener = (details) => {
      if (details.frameId === 0 && isLocalhostUrl(details.url)) {
        console.log(LOG_PREFIX, `Captured localhost redirect: ${details.url}`);
        captureLocalhostUrl(details.url);
      }
    };

    chrome.webNavigation.onBeforeNavigate.addListener(webNavListener);
    chrome.webNavigation.onCommitted.addListener(webNavListener);
    chrome.webNavigation.onErrorOccurred.addListener(webNavListener);

    // After step 7, the auth page shows a consent screen ("使用 ChatGPT 登录到 Codex")
    // with a "继续" button. Content script clicks it directly (no debugger needed).
    (async () => {
      try {
        let signupTabId = await getTabId('signup-page');
        if (signupTabId) {
          await chrome.tabs.update(signupTabId, { active: true });
          await addLog('Step 8: Switched to auth page...');
        } else {
          signupTabId = await reuseOrCreateTab('signup-page', state.oauthUrl);
          await addLog('Step 8: Auth tab reopened...');
        }

        const clickResult = await sendToContentScript('signup-page', {
          type: 'STEP8_FIND_AND_CLICK',
          source: 'background',
          payload: {},
        });

        if (clickResult?.error) {
          throw new Error(clickResult.error);
        }

        await addLog('Step 8: "继续" button clicked, waiting for redirect...');

        // Poll tab URL in case webNavigation listeners missed the redirect
        for (let i = 0; i < 30 && !resolved; i++) {
          await new Promise(r => setTimeout(r, 1000));
          try {
            const tab = await chrome.tabs.get(signupTabId);
            if (isLocalhostUrl(tab.url)) {
              captureLocalhostUrl(tab.url);
              break;
            }
          } catch { break; }
        }
      } catch (err) {
        clearTimeout(timeout);
        cleanupListeners();
        reject(err);
      }
    })();
  });
}

// ============================================================
// Step 9: VPS Verify (via vps-panel.js)
// ============================================================

async function executeStep9(state) {
  if (!state.localhostUrl) {
    throw new Error('No localhost URL. Complete step 8 first.');
  }
  if (!state.vpsUrl) {
    throw new Error('VPS URL not set. Please enter VPS URL in the side panel.');
  }

  await addLog('Step 9: Opening VPS panel...');

  let tabId = await getTabId('vps-panel');
  const alive = tabId && await isTabAlive('vps-panel');

  if (!alive) {
    // Create new tab in the automation window
    const wid = await ensureAutomationWindowId();
    const tab = await chrome.tabs.create({ url: state.vpsUrl, active: true, windowId: wid });
    tabId = tab.id;
    await new Promise(resolve => {
      const listener = (tid, info) => {
        if (tid === tabId && info.status === 'complete') {
          chrome.tabs.onUpdated.removeListener(listener);
          resolve();
        }
      };
      chrome.tabs.onUpdated.addListener(listener);
    });
  } else {
    await chrome.tabs.update(tabId, { active: true });
  }

  // Inject scripts directly and wait for them to be ready
  await chrome.scripting.executeScript({
    target: { tabId },
    files: ['content/utils.js', 'content/vps-panel.js'],
  });
  await new Promise(r => setTimeout(r, 1000));

  // Send command directly — bypass queue/ready mechanism
  await addLog(`Step 9: Filling callback URL...`);
  await chrome.tabs.sendMessage(tabId, {
    type: 'EXECUTE_STEP',
    step: 9,
    source: 'background',
    payload: { localhostUrl: state.localhostUrl },
  });
}

// ============================================================
// Open Side Panel on extension icon click
// ============================================================

chrome.sidePanel.setPanelBehavior({ openPanelOnActionClick: true });