feat: add verification flow helpers and integrate into background script

- Introduced a new module `verification-flow.js` containing verification flow helpers.
- Updated `background.js` to import and utilize the new verification flow helpers.
- Refactored existing verification-related functions to leverage the new helpers for improved code organization and maintainability.
- Added tests for the verification flow module to ensure proper integration and functionality.

background.js

@@ -4,6 +4,7 @@ importScripts(
   'background/panel-bridge.js',
   'background/generated-email-helpers.js',
   'background/signup-flow-helpers.js',
+  'background/verification-flow.js',
   'background/steps/registry.js',
   'background/steps/open-chatgpt.js',
   'background/steps/submit-signup-email.js',
@@ -6405,6 +6406,33 @@ const signupFlowHelpers = self.MultiPageSignupFlowHelpers?.createSignupFlowHelpe
   SIGNUP_PAGE_INJECT_FILES,
   waitForTabUrlMatch,
 });
+const verificationFlowHelpers = self.MultiPageBackgroundVerificationFlow?.createVerificationFlowHelpers({
+  addLog,
+  chrome,
+  CLOUDFLARE_TEMP_EMAIL_PROVIDER,
+  completeStepFromBackground,
+  confirmCustomVerificationStepBypassRequest: (step) => chrome.runtime.sendMessage({
+    type: 'REQUEST_CUSTOM_VERIFICATION_BYPASS_CONFIRMATION',
+    payload: { step },
+  }),
+  getHotmailVerificationPollConfig,
+  getHotmailVerificationRequestTimestamp,
+  getState,
+  getTabId,
+  HOTMAIL_PROVIDER,
+  isStopError,
+  LUCKMAIL_PROVIDER,
+  pollCloudflareTempEmailVerificationCode,
+  pollHotmailVerificationCode,
+  pollLuckmailVerificationCode,
+  sendToContentScript,
+  sendToMailContentScriptResilient,
+  setState,
+  setStepStatus,
+  sleepWithStop,
+  throwIfStopped,
+  VERIFICATION_POLL_MAX_ROUNDS,
+});
 const step1Executor = self.MultiPageBackgroundStep1?.createStep1Executor({
   addLog,
   completeStepFromBackground,
@@ -6439,14 +6467,14 @@ const step4Executor = self.MultiPageBackgroundStep4?.createStep4Executor({
   addLog,
   chrome,
   completeStepFromBackground,
-  confirmCustomVerificationStepBypass,
+  confirmCustomVerificationStepBypass: verificationFlowHelpers.confirmCustomVerificationStepBypass,
   getMailConfig,
   getTabId,
   HOTMAIL_PROVIDER,
   isTabAlive,
   LUCKMAIL_PROVIDER,
   CLOUDFLARE_TEMP_EMAIL_PROVIDER,
-  resolveVerificationStep,
+  resolveVerificationStep: verificationFlowHelpers.resolveVerificationStep,
   reuseOrCreateTab,
   sendToContentScriptResilient,
   shouldUseCustomRegistrationEmail,
@@ -6483,7 +6511,7 @@ const step7Executor = self.MultiPageBackgroundStep7?.createStep7Executor({
   addLog,
   chrome,
   CLOUDFLARE_TEMP_EMAIL_PROVIDER,
-  confirmCustomVerificationStepBypass,
+  confirmCustomVerificationStepBypass: verificationFlowHelpers.confirmCustomVerificationStepBypass,
   ensureStep7VerificationPageReady,
   executeStep6: (...args) => executeStep6(...args),
   getMailConfig,
@@ -6493,7 +6521,7 @@ const step7Executor = self.MultiPageBackgroundStep7?.createStep7Executor({
   isTabAlive,
   isVerificationMailPollingError,
   LUCKMAIL_PROVIDER,
-  resolveVerificationStep,
+  resolveVerificationStep: verificationFlowHelpers.resolveVerificationStep,
   reuseOrCreateTab,
   setState,
   setStepStatus,
@@ -6677,452 +6705,39 @@ function normalizeInbucketOrigin(rawValue) {
 }
 
 function getVerificationCodeStateKey(step) {
-  return step === 4 ? 'lastSignupCode' : 'lastLoginCode';
+  return verificationFlowHelpers.getVerificationCodeStateKey(step);
 }
 
 function getVerificationCodeLabel(step) {
-  return step === 4 ? '注册' : '登录';
+  return verificationFlowHelpers.getVerificationCodeLabel(step);
 }
 
 async function confirmCustomVerificationStepBypass(step) {
-  const verificationLabel = getVerificationCodeLabel(step);
-  await addLog(`步骤 ${step}：当前为自定义邮箱模式，请手动在页面中输入${verificationLabel}验证码并进入下一页面。`, 'warn');
-
-  let response = null;
-  try {
-    response = await chrome.runtime.sendMessage({
-      type: 'REQUEST_CUSTOM_VERIFICATION_BYPASS_CONFIRMATION',
-      payload: { step },
-    });
-  } catch {
-    throw new Error(`步骤 ${step}：无法打开确认弹窗，请先保持侧边栏打开后重试。`);
-  }
-
-  if (response?.error) {
-    throw new Error(response.error);
-  }
-  if (!response?.confirmed) {
-    throw new Error(`步骤 ${step}：已取消手动${verificationLabel}验证码确认。`);
-  }
-
-  await setState({
-    lastEmailTimestamp: null,
-    signupVerificationRequestedAt: null,
-    loginVerificationRequestedAt: null,
-  });
-  await setStepStatus(step, 'skipped');
-  await addLog(`步骤 ${step}：已确认手动完成${verificationLabel}验证码输入，当前步骤已跳过。`, 'warn');
+  return verificationFlowHelpers.confirmCustomVerificationStepBypass(step);
 }
 
 function getVerificationPollPayload(step, state, overrides = {}) {
-  if (step === 4) {
-    return {
-      filterAfterTimestamp: getHotmailVerificationRequestTimestamp(4, state),
-      senderFilters: ['openai', 'noreply', 'verify', 'auth', 'duckduckgo', 'forward'],
-      subjectFilters: ['verify', 'verification', 'code', '楠岃瘉', 'confirm'],
-      targetEmail: state.email,
-      maxAttempts: 5,
-      intervalMs: 3000,
-      ...overrides,
-    };
-  }
-
-  return {
-    filterAfterTimestamp: getHotmailVerificationRequestTimestamp(7, state),
-    senderFilters: ['openai', 'noreply', 'verify', 'auth', 'chatgpt', 'duckduckgo', 'forward'],
-    subjectFilters: ['verify', 'verification', 'code', '楠岃瘉', 'confirm', 'login'],
-    targetEmail: state.email,
-    maxAttempts: 5,
-    intervalMs: 3000,
-    ...overrides,
-  };
+  return verificationFlowHelpers.getVerificationPollPayload(step, state, overrides);
 }
 
 async function requestVerificationCodeResend(step) {
-  throwIfStopped();
-  const signupTabId = await getTabId('signup-page');
-  if (!signupTabId) {
-    throw new Error('认证页面标签页已关闭，无法重新请求验证码。');
-  }
-
-  throwIfStopped();
-  await chrome.tabs.update(signupTabId, { active: true });
-  throwIfStopped();
-  await addLog(`步骤 ${step}：正在请求新的${getVerificationCodeLabel(step)}验证码...`, 'warn');
-  throwIfStopped();
-
-  const result = await sendToContentScript('signup-page', {
-    type: 'RESEND_VERIFICATION_CODE',
-    step,
-    source: 'background',
-    payload: {},
-  });
-
-  if (result && result.error) {
-    throw new Error(result.error);
-  }
-
-  const requestedAt = Date.now();
-  if (step === 7) {
-    await setState({ loginVerificationRequestedAt: requestedAt });
-  }
-
-  const currentState = await getState();
-  if (currentState.mailProvider === '2925') {
-    const mailTabId = await getTabId('mail-2925');
-    if (mailTabId) {
-      await chrome.tabs.update(mailTabId, { active: true });
-      await addLog(`步骤 ${step}：已切换到 2925 邮箱标签页等待新邮件。`, 'info');
-    }
-  }
-
-  return requestedAt;
+  return verificationFlowHelpers.requestVerificationCodeResend(step);
 }
 
 async function pollFreshVerificationCode(step, state, mail, pollOverrides = {}) {
-  const { onResendRequestedAt, ...cleanPollOverrides } = pollOverrides;
-
-  if (mail.provider === HOTMAIL_PROVIDER) {
-    const hotmailPollConfig = getHotmailVerificationPollConfig(step);
-    return pollHotmailVerificationCode(step, state, {
-      ...getVerificationPollPayload(step, state),
-      ...hotmailPollConfig,
-      ...cleanPollOverrides,
-    });
-  }
-  if (mail.provider === LUCKMAIL_PROVIDER) {
-    return pollLuckmailVerificationCode(step, state, {
-      ...getVerificationPollPayload(step, state),
-      ...pollOverrides,
-    });
-  }
-  if (mail.provider === CLOUDFLARE_TEMP_EMAIL_PROVIDER) {
-    return pollCloudflareTempEmailVerificationCode(step, state, {
-      ...getVerificationPollPayload(step, state),
-      ...pollOverrides,
-    });
-  }
-
-  if (Number(pollOverrides.resendIntervalMs) > 0) {
-    return pollFreshVerificationCodeWithResendInterval(step, state, mail, pollOverrides);
-  }
-
-  const stateKey = getVerificationCodeStateKey(step);
-  const rejectedCodes = new Set();
-  if (state[stateKey]) {
-    rejectedCodes.add(state[stateKey]);
-  }
-  for (const code of (pollOverrides.excludeCodes || [])) {
-    if (code) rejectedCodes.add(code);
-  }
-
-  let lastError = null;
-  let filterAfterTimestamp = cleanPollOverrides.filterAfterTimestamp ?? getVerificationPollPayload(step, state).filterAfterTimestamp;
-  const maxRounds = pollOverrides.maxRounds || VERIFICATION_POLL_MAX_ROUNDS;
-
-  for (let round = 1; round <= maxRounds; round++) {
-    throwIfStopped();
-    if (round > 1) {
-      const requestedAt = await requestVerificationCodeResend(step);
-      if (typeof onResendRequestedAt === 'function') {
-        const nextFilterAfterTimestamp = await onResendRequestedAt(requestedAt);
-        if (nextFilterAfterTimestamp !== undefined) {
-          filterAfterTimestamp = nextFilterAfterTimestamp;
-        }
-      }
-    }
-
-    const payload = getVerificationPollPayload(step, state, {
-      ...cleanPollOverrides,
-      filterAfterTimestamp,
-      excludeCodes: [...rejectedCodes],
-    });
-
-    try {
-      const result = await sendToMailContentScriptResilient(
-        mail,
-        {
-          type: 'POLL_EMAIL',
-          step,
-          source: 'background',
-          payload,
-        },
-        {
-          timeoutMs: 45000,
-          maxRecoveryAttempts: 2,
-        }
-      );
-
-      if (result && result.error) {
-        throw new Error(result.error);
-      }
-
-      if (!result || !result.code) {
-        throw new Error(`步骤 ${step}：邮箱轮询结束，但未获取到验证码。`);
-      }
-
-      if (rejectedCodes.has(result.code)) {
-        throw new Error(`步骤 ${step}：再次收到了相同的${getVerificationCodeLabel(step)}验证码：${result.code}`);
-      }
-
-      return result;
-    } catch (err) {
-      if (isStopError(err)) {
-        throw err;
-      }
-      lastError = err;
-      await addLog(`步骤 ${step}：${err.message}`, 'warn');
-      if (round < maxRounds) {
-        await addLog(`步骤 ${step}：将重新发送验证码后重试（${round + 1}/${maxRounds}）...`, 'warn');
-      }
-    }
-  }
-
-  throw lastError || new Error(`步骤 ${step}：无法获取新的${getVerificationCodeLabel(step)}验证码。`);
+  return verificationFlowHelpers.pollFreshVerificationCode(step, state, mail, pollOverrides);
 }
 
 async function pollFreshVerificationCodeWithResendInterval(step, state, mail, pollOverrides = {}) {
-  const stateKey = getVerificationCodeStateKey(step);
-  const rejectedCodes = new Set();
-  if (state[stateKey]) {
-    rejectedCodes.add(state[stateKey]);
-  }
-  for (const code of (pollOverrides.excludeCodes || [])) {
-    if (code) rejectedCodes.add(code);
-  }
-
-  const {
-    maxRounds: _ignoredMaxRounds,
-    resendIntervalMs: _ignoredResendIntervalMs,
-    lastResendAt: _ignoredLastResendAt,
-    onResendRequestedAt: _ignoredOnResendRequestedAt,
-    ...payloadOverrides
-  } = pollOverrides;
-  const onResendRequestedAt = typeof pollOverrides.onResendRequestedAt === 'function'
-    ? pollOverrides.onResendRequestedAt
-    : null;
-  let lastError = null;
-  let filterAfterTimestamp = payloadOverrides.filterAfterTimestamp ?? getVerificationPollPayload(step, state).filterAfterTimestamp;
-  const maxRounds = pollOverrides.maxRounds || VERIFICATION_POLL_MAX_ROUNDS;
-  const resendIntervalMs = Math.max(0, Number(pollOverrides.resendIntervalMs) || 0);
-  let lastResendAt = Number(pollOverrides.lastResendAt) || 0;
-
-  for (let round = 1; round <= maxRounds; round++) {
-    throwIfStopped();
-    if (round > 1) {
-      lastResendAt = await requestVerificationCodeResend(step);
-      if (onResendRequestedAt) {
-        const nextFilterAfterTimestamp = await onResendRequestedAt(lastResendAt);
-        if (nextFilterAfterTimestamp !== undefined) {
-          filterAfterTimestamp = nextFilterAfterTimestamp;
-        }
-      }
-    }
-
-    while (true) {
-      throwIfStopped();
-      const payload = getVerificationPollPayload(step, state, {
-        ...payloadOverrides,
-        filterAfterTimestamp,
-        excludeCodes: [...rejectedCodes],
-      });
-
-      if (lastResendAt > 0) {
-        const remainingBeforeResendMs = Math.max(0, resendIntervalMs - (Date.now() - lastResendAt));
-        const baseMaxAttempts = Math.max(1, Number(payload.maxAttempts) || 5);
-        const intervalMs = Math.max(1, Number(payload.intervalMs) || 3000);
-        payload.maxAttempts = Math.max(1, Math.min(baseMaxAttempts, Math.floor(remainingBeforeResendMs / intervalMs) + 1));
-      }
-
-      try {
-        const result = await sendToMailContentScriptResilient(
-          mail,
-          {
-            type: 'POLL_EMAIL',
-            step,
-            source: 'background',
-            payload,
-          },
-          {
-            timeoutMs: 45000,
-            maxRecoveryAttempts: 2,
-          }
-        );
-
-        if (result && result.error) {
-          throw new Error(result.error);
-        }
-
-        if (!result || !result.code) {
-          throw new Error(`步骤 ${step}：邮箱轮询结束，但未获取到验证码。`);
-        }
-
-        if (rejectedCodes.has(result.code)) {
-          throw new Error(`步骤 ${step}：再次收到了相同的${getVerificationCodeLabel(step)}验证码：${result.code}`);
-        }
-
-        return {
-          ...result,
-          lastResendAt,
-        };
-      } catch (err) {
-        if (isStopError(err)) {
-          throw err;
-        }
-        lastError = err;
-        await addLog(`步骤 ${step}：${err.message}`, 'warn');
-      }
-
-      const remainingBeforeResendMs = lastResendAt > 0
-        ? Math.max(0, resendIntervalMs - (Date.now() - lastResendAt))
-        : 0;
-      if (remainingBeforeResendMs > 0) {
-        await addLog(
-          `步骤 ${step}：距离下次重新发送验证码还差 ${Math.ceil(remainingBeforeResendMs / 1000)} 秒，继续刷新邮箱（第 ${round}/${maxRounds} 轮）...`,
-          'info'
-        );
-        continue;
-      }
-
-      if (round < maxRounds) {
-        await addLog(`步骤 ${step}：已到 25 秒重发间隔，准备重新发送验证码（第 ${round + 1}/${maxRounds} 轮）...`, 'warn');
-      }
-      break;
-    }
-  }
-
-  throw lastError || new Error(`步骤 ${step}：无法获取新的${getVerificationCodeLabel(step)}验证码。`);
+  return verificationFlowHelpers.pollFreshVerificationCodeWithResendInterval(step, state, mail, pollOverrides);
 }
 
 async function submitVerificationCode(step, code) {
-  const signupTabId = await getTabId('signup-page');
-  if (!signupTabId) {
-    throw new Error('认证页面标签页已关闭，无法填写验证码。');
-  }
-
-  await chrome.tabs.update(signupTabId, { active: true });
-  const result = await sendToContentScript('signup-page', {
-    type: 'FILL_CODE',
-    step,
-    source: 'background',
-    payload: { code },
-  });
-
-  if (result && result.error) {
-    throw new Error(result.error);
-  }
-
-  return result || {};
+  return verificationFlowHelpers.submitVerificationCode(step, code);
 }
 
 async function resolveVerificationStep(step, state, mail, options = {}) {
-  const stateKey = getVerificationCodeStateKey(step);
-  const rejectedCodes = new Set();
-  const hotmailPollConfig = mail.provider === HOTMAIL_PROVIDER
-    ? getHotmailVerificationPollConfig(step)
-    : null;
-  const ignorePersistedLastCode = Boolean(hotmailPollConfig?.ignorePersistedLastCode);
-  if (state[stateKey] && !ignorePersistedLastCode) {
-    rejectedCodes.add(state[stateKey]);
-  }
-
-  let nextFilterAfterTimestamp = options.filterAfterTimestamp ?? null;
-  const requestFreshCodeFirst = options.requestFreshCodeFirst !== undefined
-    ? Boolean(options.requestFreshCodeFirst)
-    : (hotmailPollConfig?.requestFreshCodeFirst ?? false);
-  const maxSubmitAttempts = 3;
-  const resendIntervalMs = Math.max(0, Number(options.resendIntervalMs) || 0);
-  let lastResendAt = Number(options.lastResendAt) || 0;
-
-  const updateFilterAfterTimestampForStep7 = async (requestedAt) => {
-    if (step !== 7 || !requestedAt) {
-      return nextFilterAfterTimestamp;
-    }
-
-    if (mail.provider === HOTMAIL_PROVIDER) {
-      nextFilterAfterTimestamp = getHotmailVerificationRequestTimestamp(7, {
-        ...state,
-        loginVerificationRequestedAt: requestedAt,
-      });
-    } else {
-      nextFilterAfterTimestamp = Math.max(0, Number(requestedAt) - 60000);
-    }
-
-    return nextFilterAfterTimestamp;
-  };
-
-  if (requestFreshCodeFirst) {
-    try {
-      lastResendAt = await requestVerificationCodeResend(step);
-      await updateFilterAfterTimestampForStep7(lastResendAt);
-      await addLog(`步骤 ${step}：已先请求一封新的${getVerificationCodeLabel(step)}验证码，再开始轮询邮箱。`, 'warn');
-    } catch (err) {
-      if (isStopError(err)) {
-        throw err;
-      }
-      await addLog(`步骤 ${step}：首次重新获取验证码失败：${err.message}，将继续使用当前时间窗口轮询。`, 'warn');
-    }
-  }
-
-  if (mail.provider === HOTMAIL_PROVIDER) {
-    const initialDelayMs = Number(options.initialDelayMs ?? hotmailPollConfig.initialDelayMs) || 0;
-    if (initialDelayMs > 0) {
-      await addLog(`步骤 ${step}：等待 ${Math.round(initialDelayMs / 1000)} 秒，让 Hotmail 验证码邮件先到达...`, 'info');
-      await sleepWithStop(initialDelayMs);
-    }
-  }
-
-  for (let attempt = 1; attempt <= maxSubmitAttempts; attempt++) {
-    const result = await pollFreshVerificationCode(step, state, mail, {
-      excludeCodes: [...rejectedCodes],
-      filterAfterTimestamp: nextFilterAfterTimestamp ?? undefined,
-      resendIntervalMs,
-      lastResendAt,
-      onResendRequestedAt: updateFilterAfterTimestampForStep7,
-    });
-    lastResendAt = Number(result?.lastResendAt) || lastResendAt;
-
-    throwIfStopped();
-    await addLog(`步骤 ${step}：已获取${getVerificationCodeLabel(step)}验证码：${result.code}`);
-    throwIfStopped();
-    const submitResult = await submitVerificationCode(step, result.code);
-
-    if (submitResult.invalidCode) {
-      rejectedCodes.add(result.code);
-      await addLog(`步骤 ${step}：验证码被页面拒绝：${submitResult.errorText || result.code}`, 'warn');
-
-      if (attempt >= maxSubmitAttempts) {
-        throw new Error(`步骤 ${step}：验证码连续失败，已达到 ${maxSubmitAttempts} 次重试上限。`);
-      }
-
-      const remainingBeforeResendMs = resendIntervalMs > 0 && lastResendAt > 0
-        ? Math.max(0, resendIntervalMs - (Date.now() - lastResendAt))
-        : 0;
-      if (remainingBeforeResendMs > 0) {
-        await addLog(
-          `步骤 ${step}：提交失败后距离下次重新发送验证码还差 ${Math.ceil(remainingBeforeResendMs / 1000)} 秒，先继续刷新邮箱（${attempt + 1}/${maxSubmitAttempts}）...`,
-          'warn'
-        );
-        continue;
-      }
-
-      lastResendAt = await requestVerificationCodeResend(step);
-      await updateFilterAfterTimestampForStep7(lastResendAt);
-      await addLog(`步骤 ${step}：提交失败后已请求新验证码（${attempt + 1}/${maxSubmitAttempts}）...`, 'warn');
-      continue;
-    }
-
-    await setState({
-      lastEmailTimestamp: result.emailTimestamp,
-      [stateKey]: result.code,
-    });
-
-    await completeStepFromBackground(step, {
-      emailTimestamp: result.emailTimestamp,
-      code: result.code,
-    });
-    return;
-  }
+  return verificationFlowHelpers.resolveVerificationStep(step, state, mail, options);
 }
 
 async function executeStep4(state) {

background/verification-flow.js

@@ -0,0 +1,491 @@
+(function attachBackgroundVerificationFlow(root, factory) {
+  root.MultiPageBackgroundVerificationFlow = factory();
+})(typeof self !== 'undefined' ? self : globalThis, function createBackgroundVerificationFlowModule() {
+  function createVerificationFlowHelpers(deps = {}) {
+    const {
+      addLog,
+      chrome,
+      CLOUDFLARE_TEMP_EMAIL_PROVIDER,
+      completeStepFromBackground,
+      confirmCustomVerificationStepBypassRequest,
+      getHotmailVerificationPollConfig,
+      getHotmailVerificationRequestTimestamp,
+      getState,
+      getTabId,
+      HOTMAIL_PROVIDER,
+      isStopError,
+      LUCKMAIL_PROVIDER,
+      pollCloudflareTempEmailVerificationCode,
+      pollHotmailVerificationCode,
+      pollLuckmailVerificationCode,
+      sendToContentScript,
+      sendToMailContentScriptResilient,
+      setState,
+      sleepWithStop,
+      throwIfStopped,
+      VERIFICATION_POLL_MAX_ROUNDS,
+    } = deps;
+
+    function getVerificationCodeStateKey(step) {
+      return step === 4 ? 'lastSignupCode' : 'lastLoginCode';
+    }
+
+    function getVerificationCodeLabel(step) {
+      return step === 4 ? '注册' : '登录';
+    }
+
+    async function confirmCustomVerificationStepBypass(step) {
+      const verificationLabel = getVerificationCodeLabel(step);
+      await addLog(`步骤 ${step}：当前为自定义邮箱模式，请手动在页面中输入${verificationLabel}验证码并进入下一页面。`, 'warn');
+
+      let response = null;
+      try {
+        response = await confirmCustomVerificationStepBypassRequest(step);
+      } catch {
+        throw new Error(`步骤 ${step}：无法打开确认弹窗，请先保持侧边栏打开后重试。`);
+      }
+
+      if (response?.error) {
+        throw new Error(response.error);
+      }
+      if (!response?.confirmed) {
+        throw new Error(`步骤 ${step}：已取消手动${verificationLabel}验证码确认。`);
+      }
+
+      await setState({
+        lastEmailTimestamp: null,
+        signupVerificationRequestedAt: null,
+        loginVerificationRequestedAt: null,
+      });
+      await deps.setStepStatus(step, 'skipped');
+      await addLog(`步骤 ${step}：已确认手动完成${verificationLabel}验证码输入，当前步骤已跳过。`, 'warn');
+    }
+
+    function getVerificationPollPayload(step, state, overrides = {}) {
+      if (step === 4) {
+        return {
+          filterAfterTimestamp: getHotmailVerificationRequestTimestamp(4, state),
+          senderFilters: ['openai', 'noreply', 'verify', 'auth', 'duckduckgo', 'forward'],
+          subjectFilters: ['verify', 'verification', 'code', '验证码', 'confirm'],
+          targetEmail: state.email,
+          maxAttempts: 5,
+          intervalMs: 3000,
+          ...overrides,
+        };
+      }
+
+      return {
+        filterAfterTimestamp: getHotmailVerificationRequestTimestamp(7, state),
+        senderFilters: ['openai', 'noreply', 'verify', 'auth', 'chatgpt', 'duckduckgo', 'forward'],
+        subjectFilters: ['verify', 'verification', 'code', '验证码', 'confirm', 'login'],
+        targetEmail: state.email,
+        maxAttempts: 5,
+        intervalMs: 3000,
+        ...overrides,
+      };
+    }
+
+    async function requestVerificationCodeResend(step) {
+      throwIfStopped();
+      const signupTabId = await getTabId('signup-page');
+      if (!signupTabId) {
+        throw new Error('认证页面标签页已关闭，无法重新请求验证码。');
+      }
+
+      throwIfStopped();
+      await chrome.tabs.update(signupTabId, { active: true });
+      throwIfStopped();
+
+      const result = await sendToContentScript('signup-page', {
+        type: 'RESEND_VERIFICATION_CODE',
+        step,
+        source: 'background',
+        payload: {},
+      });
+
+      if (result && result.error) {
+        throw new Error(result.error);
+      }
+
+      await addLog(`步骤 ${step}：已请求新的${getVerificationCodeLabel(step)}验证码。`, 'warn');
+
+      const requestedAt = Date.now();
+      if (step === 7) {
+        await setState({ loginVerificationRequestedAt: requestedAt });
+      }
+
+      const currentState = await getState();
+      if (currentState.mailProvider === '2925') {
+        const mailTabId = await getTabId('mail-2925');
+        if (mailTabId) {
+          await chrome.tabs.update(mailTabId, { active: true });
+          await addLog(`步骤 ${step}：已切换到 2925 邮箱标签页等待新邮件。`, 'info');
+        }
+      }
+
+      return requestedAt;
+    }
+
+    async function pollFreshVerificationCodeWithResendInterval(step, state, mail, pollOverrides = {}) {
+      const stateKey = getVerificationCodeStateKey(step);
+      const rejectedCodes = new Set();
+      if (state[stateKey]) {
+        rejectedCodes.add(state[stateKey]);
+      }
+      for (const code of (pollOverrides.excludeCodes || [])) {
+        if (code) rejectedCodes.add(code);
+      }
+
+      const {
+        maxRounds: _ignoredMaxRounds,
+        resendIntervalMs: _ignoredResendIntervalMs,
+        lastResendAt: _ignoredLastResendAt,
+        onResendRequestedAt: _ignoredOnResendRequestedAt,
+        ...payloadOverrides
+      } = pollOverrides;
+      const onResendRequestedAt = typeof pollOverrides.onResendRequestedAt === 'function'
+        ? pollOverrides.onResendRequestedAt
+        : null;
+      let lastError = null;
+      let filterAfterTimestamp = payloadOverrides.filterAfterTimestamp ?? getVerificationPollPayload(step, state).filterAfterTimestamp;
+      const maxRounds = pollOverrides.maxRounds || VERIFICATION_POLL_MAX_ROUNDS;
+      const resendIntervalMs = Math.max(0, Number(pollOverrides.resendIntervalMs) || 0);
+      let lastResendAt = Number(pollOverrides.lastResendAt) || 0;
+
+      for (let round = 1; round <= maxRounds; round++) {
+        throwIfStopped();
+        if (round > 1) {
+          lastResendAt = await requestVerificationCodeResend(step);
+          if (onResendRequestedAt) {
+            const nextFilterAfterTimestamp = await onResendRequestedAt(lastResendAt);
+            if (nextFilterAfterTimestamp !== undefined) {
+              filterAfterTimestamp = nextFilterAfterTimestamp;
+            }
+          }
+        }
+
+        while (true) {
+          throwIfStopped();
+          const payload = getVerificationPollPayload(step, state, {
+            ...payloadOverrides,
+            filterAfterTimestamp,
+            excludeCodes: [...rejectedCodes],
+          });
+
+          if (lastResendAt > 0) {
+            const remainingBeforeResendMs = Math.max(0, resendIntervalMs - (Date.now() - lastResendAt));
+            const baseMaxAttempts = Math.max(1, Number(payload.maxAttempts) || 5);
+            const intervalMs = Math.max(1, Number(payload.intervalMs) || 3000);
+            payload.maxAttempts = Math.max(1, Math.min(baseMaxAttempts, Math.floor(remainingBeforeResendMs / intervalMs) + 1));
+          }
+
+          try {
+            const result = await sendToMailContentScriptResilient(
+              mail,
+              {
+                type: 'POLL_EMAIL',
+                step,
+                source: 'background',
+                payload,
+              },
+              {
+                timeoutMs: 45000,
+                maxRecoveryAttempts: 2,
+              }
+            );
+
+            if (result && result.error) {
+              throw new Error(result.error);
+            }
+
+            if (!result || !result.code) {
+              throw new Error(`步骤 ${step}：邮箱轮询结束，但未获取到验证码。`);
+            }
+
+            if (rejectedCodes.has(result.code)) {
+              throw new Error(`步骤 ${step}：再次收到了相同的${getVerificationCodeLabel(step)}验证码：${result.code}`);
+            }
+
+            return {
+              ...result,
+              lastResendAt,
+            };
+          } catch (err) {
+            if (isStopError(err)) {
+              throw err;
+            }
+            lastError = err;
+            await addLog(`步骤 ${step}：${err.message}`, 'warn');
+          }
+
+          const remainingBeforeResendMs = lastResendAt > 0
+            ? Math.max(0, resendIntervalMs - (Date.now() - lastResendAt))
+            : 0;
+          if (remainingBeforeResendMs > 0) {
+            await addLog(
+              `步骤 ${step}：距离下次重新发送验证码还差 ${Math.ceil(remainingBeforeResendMs / 1000)} 秒，继续刷新邮箱（第 ${round}/${maxRounds} 轮）...`,
+              'info'
+            );
+            continue;
+          }
+
+          if (round < maxRounds) {
+            await addLog(`步骤 ${step}：已到 25 秒重发间隔，准备重新发送验证码（第 ${round + 1}/${maxRounds} 轮）...`, 'warn');
+          }
+          break;
+        }
+      }
+
+      throw lastError || new Error(`步骤 ${step}：无法获取新的${getVerificationCodeLabel(step)}验证码。`);
+    }
+
+    async function pollFreshVerificationCode(step, state, mail, pollOverrides = {}) {
+      const { onResendRequestedAt, ...cleanPollOverrides } = pollOverrides;
+
+      if (mail.provider === HOTMAIL_PROVIDER) {
+        const hotmailPollConfig = getHotmailVerificationPollConfig(step);
+        return pollHotmailVerificationCode(step, state, {
+          ...getVerificationPollPayload(step, state),
+          ...hotmailPollConfig,
+          ...cleanPollOverrides,
+        });
+      }
+      if (mail.provider === LUCKMAIL_PROVIDER) {
+        return pollLuckmailVerificationCode(step, state, {
+          ...getVerificationPollPayload(step, state),
+          ...pollOverrides,
+        });
+      }
+      if (mail.provider === CLOUDFLARE_TEMP_EMAIL_PROVIDER) {
+        return pollCloudflareTempEmailVerificationCode(step, state, {
+          ...getVerificationPollPayload(step, state),
+          ...pollOverrides,
+        });
+      }
+
+      if (Number(pollOverrides.resendIntervalMs) > 0) {
+        return pollFreshVerificationCodeWithResendInterval(step, state, mail, pollOverrides);
+      }
+
+      const stateKey = getVerificationCodeStateKey(step);
+      const rejectedCodes = new Set();
+      if (state[stateKey]) {
+        rejectedCodes.add(state[stateKey]);
+      }
+      for (const code of (pollOverrides.excludeCodes || [])) {
+        if (code) rejectedCodes.add(code);
+      }
+
+      let lastError = null;
+      let filterAfterTimestamp = cleanPollOverrides.filterAfterTimestamp ?? getVerificationPollPayload(step, state).filterAfterTimestamp;
+      const maxRounds = pollOverrides.maxRounds || VERIFICATION_POLL_MAX_ROUNDS;
+
+      for (let round = 1; round <= maxRounds; round++) {
+        throwIfStopped();
+        if (round > 1) {
+          const requestedAt = await requestVerificationCodeResend(step);
+          if (typeof onResendRequestedAt === 'function') {
+            const nextFilterAfterTimestamp = await onResendRequestedAt(requestedAt);
+            if (nextFilterAfterTimestamp !== undefined) {
+              filterAfterTimestamp = nextFilterAfterTimestamp;
+            }
+          }
+        }
+
+        const payload = getVerificationPollPayload(step, state, {
+          ...cleanPollOverrides,
+          filterAfterTimestamp,
+          excludeCodes: [...rejectedCodes],
+        });
+
+        try {
+          const result = await sendToMailContentScriptResilient(
+            mail,
+            {
+              type: 'POLL_EMAIL',
+              step,
+              source: 'background',
+              payload,
+            },
+            {
+              timeoutMs: 45000,
+              maxRecoveryAttempts: 2,
+            }
+          );
+
+          if (result && result.error) {
+            throw new Error(result.error);
+          }
+
+          if (!result || !result.code) {
+            throw new Error(`步骤 ${step}：邮箱轮询结束，但未获取到验证码。`);
+          }
+
+          if (rejectedCodes.has(result.code)) {
+            throw new Error(`步骤 ${step}：再次收到了相同的${getVerificationCodeLabel(step)}验证码：${result.code}`);
+          }
+
+          return result;
+        } catch (err) {
+          if (isStopError(err)) {
+            throw err;
+          }
+          lastError = err;
+          await addLog(`步骤 ${step}：${err.message}`, 'warn');
+          if (round < maxRounds) {
+            await addLog(`步骤 ${step}：将重新发送验证码后重试（${round + 1}/${maxRounds}）...`, 'warn');
+          }
+        }
+      }
+
+      throw lastError || new Error(`步骤 ${step}：无法获取新的${getVerificationCodeLabel(step)}验证码。`);
+    }
+
+    async function submitVerificationCode(step, code) {
+      const signupTabId = await getTabId('signup-page');
+      if (!signupTabId) {
+        throw new Error('认证页面标签页已关闭，无法填写验证码。');
+      }
+
+      await chrome.tabs.update(signupTabId, { active: true });
+      const result = await sendToContentScript('signup-page', {
+        type: 'FILL_CODE',
+        step,
+        source: 'background',
+        payload: { code },
+      });
+
+      if (result && result.error) {
+        throw new Error(result.error);
+      }
+
+      return result || {};
+    }
+
+    async function resolveVerificationStep(step, state, mail, options = {}) {
+      const stateKey = getVerificationCodeStateKey(step);
+      const rejectedCodes = new Set();
+      const hotmailPollConfig = mail.provider === HOTMAIL_PROVIDER
+        ? getHotmailVerificationPollConfig(step)
+        : null;
+      const ignorePersistedLastCode = Boolean(hotmailPollConfig?.ignorePersistedLastCode);
+      if (state[stateKey] && !ignorePersistedLastCode) {
+        rejectedCodes.add(state[stateKey]);
+      }
+
+      let nextFilterAfterTimestamp = options.filterAfterTimestamp ?? null;
+      const requestFreshCodeFirst = options.requestFreshCodeFirst !== undefined
+        ? Boolean(options.requestFreshCodeFirst)
+        : (hotmailPollConfig?.requestFreshCodeFirst ?? false);
+      const maxSubmitAttempts = 3;
+      const resendIntervalMs = Math.max(0, Number(options.resendIntervalMs) || 0);
+      let lastResendAt = Number(options.lastResendAt) || 0;
+
+      const updateFilterAfterTimestampForStep7 = async (requestedAt) => {
+        if (step !== 7 || !requestedAt) {
+          return nextFilterAfterTimestamp;
+        }
+
+        if (mail.provider === HOTMAIL_PROVIDER) {
+          nextFilterAfterTimestamp = getHotmailVerificationRequestTimestamp(7, {
+            ...state,
+            loginVerificationRequestedAt: requestedAt,
+          });
+        } else {
+          nextFilterAfterTimestamp = Math.max(0, Number(requestedAt) - 60000);
+        }
+
+        return nextFilterAfterTimestamp;
+      };
+
+      if (requestFreshCodeFirst) {
+        try {
+          lastResendAt = await requestVerificationCodeResend(step);
+          await updateFilterAfterTimestampForStep7(lastResendAt);
+          await addLog(`步骤 ${step}：已先请求一封新的${getVerificationCodeLabel(step)}验证码，再开始轮询邮箱。`, 'warn');
+        } catch (err) {
+          if (isStopError(err)) {
+            throw err;
+          }
+          await addLog(`步骤 ${step}：首次重新获取验证码失败：${err.message}，将继续使用当前时间窗口轮询。`, 'warn');
+        }
+      }
+
+      if (mail.provider === HOTMAIL_PROVIDER) {
+        const initialDelayMs = Number(options.initialDelayMs ?? hotmailPollConfig.initialDelayMs) || 0;
+        if (initialDelayMs > 0) {
+          await addLog(`步骤 ${step}：等待 ${Math.round(initialDelayMs / 1000)} 秒，让 Hotmail 验证码邮件先到达...`, 'info');
+          await sleepWithStop(initialDelayMs);
+        }
+      }
+
+      for (let attempt = 1; attempt <= maxSubmitAttempts; attempt++) {
+        const result = await pollFreshVerificationCode(step, state, mail, {
+          excludeCodes: [...rejectedCodes],
+          filterAfterTimestamp: nextFilterAfterTimestamp ?? undefined,
+          resendIntervalMs,
+          lastResendAt,
+          onResendRequestedAt: updateFilterAfterTimestampForStep7,
+        });
+        lastResendAt = Number(result?.lastResendAt) || lastResendAt;
+
+        throwIfStopped();
+        await addLog(`步骤 ${step}：已获取${getVerificationCodeLabel(step)}验证码：${result.code}`);
+        throwIfStopped();
+        const submitResult = await submitVerificationCode(step, result.code);
+
+        if (submitResult.invalidCode) {
+          rejectedCodes.add(result.code);
+          await addLog(`步骤 ${step}：验证码被页面拒绝：${submitResult.errorText || result.code}`, 'warn');
+
+          if (attempt >= maxSubmitAttempts) {
+            throw new Error(`步骤 ${step}：验证码连续失败，已达到 ${maxSubmitAttempts} 次重试上限。`);
+          }
+
+          const remainingBeforeResendMs = resendIntervalMs > 0 && lastResendAt > 0
+            ? Math.max(0, resendIntervalMs - (Date.now() - lastResendAt))
+            : 0;
+          if (remainingBeforeResendMs > 0) {
+            await addLog(
+              `步骤 ${step}：提交失败后距离下次重新发送验证码还差 ${Math.ceil(remainingBeforeResendMs / 1000)} 秒，先继续刷新邮箱（${attempt + 1}/${maxSubmitAttempts}）...`,
+              'warn'
+            );
+            continue;
+          }
+
+          lastResendAt = await requestVerificationCodeResend(step);
+          await updateFilterAfterTimestampForStep7(lastResendAt);
+          await addLog(`步骤 ${step}：提交失败后已请求新验证码（${attempt + 1}/${maxSubmitAttempts}）...`, 'warn');
+          continue;
+        }
+
+        await setState({
+          lastEmailTimestamp: result.emailTimestamp,
+          [stateKey]: result.code,
+        });
+
+        await completeStepFromBackground(step, {
+          emailTimestamp: result.emailTimestamp,
+          code: result.code,
+        });
+        return;
+      }
+    }
+
+    return {
+      confirmCustomVerificationStepBypass,
+      getVerificationCodeLabel,
+      getVerificationCodeStateKey,
+      getVerificationPollPayload,
+      pollFreshVerificationCode,
+      pollFreshVerificationCodeWithResendInterval,
+      requestVerificationCodeResend,
+      resolveVerificationStep,
+      submitVerificationCode,
+    };
+  }
+
+  return {
+    createVerificationFlowHelpers,
+  };
+});

tests/background-verification-flow-module.test.js

@@ -0,0 +1,17 @@
+const test = require('node:test');
+const assert = require('node:assert/strict');
+const fs = require('node:fs');
+
+test('background imports verification flow module', () => {
+  const source = fs.readFileSync('background.js', 'utf8');
+  assert.match(source, /background\/verification-flow\.js/);
+});
+
+test('verification flow module exposes a factory', () => {
+  const source = fs.readFileSync('background/verification-flow.js', 'utf8');
+  const globalScope = {};
+
+  const api = new Function('self', `${source}; return self.MultiPageBackgroundVerificationFlow;`)(globalScope);
+
+  assert.equal(typeof api?.createVerificationFlowHelpers, 'function');
+});

tests/verification-stop-propagation.test.js

@@ -1,9 +1,10 @@
 const assert = require('assert');
 const fs = require('fs');
 
-const source = fs.readFileSync('background.js', 'utf8');
+const helperSource = fs.readFileSync('background.js', 'utf8');
+const verificationFlowSource = fs.readFileSync('background/verification-flow.js', 'utf8');
 
-function extractFunction(name) {
+function extractFunction(source, name) {
   const markers = [`async function ${name}(`, `function ${name}(`];
   const start = markers
     .map(marker => source.indexOf(marker))
@@ -51,13 +52,13 @@ function extractFunction(name) {
 }
 
 async function testPollFreshVerificationCodeRethrowsStop() {
-  const bundle = [
-    extractFunction('isStopError'),
-    extractFunction('throwIfStopped'),
-    extractFunction('pollFreshVerificationCode'),
+  const helperBundle = [
+    extractFunction(helperSource, 'isStopError'),
+    extractFunction(helperSource, 'throwIfStopped'),
   ].join('\n');
 
-const api = new Function(`
+const api = new Function('verificationFlowSource', `
+const self = {};
 let stopRequested = false;
 const STOP_ERROR_MESSAGE = '流程已被用户停止。';
 const HOTMAIL_PROVIDER = 'hotmail-api';
@@ -76,14 +77,8 @@ async function pollHotmailVerificationCode() {
 async function pollLuckmailVerificationCode() {
   throw new Error('luckmail path should not run in this test');
 }
-function getVerificationCodeStateKey(step) {
-  return step === 4 ? 'lastSignupCode' : 'lastLoginCode';
-}
-function getVerificationPollPayload(step, state, overrides = {}) {
-  return {
-    filterAfterTimestamp: 123,
-    ...overrides,
-  };
+async function pollCloudflareTempEmailVerificationCode() {
+  throw new Error('cloudflare path should not run in this test');
 }
 async function sendToMailContentScriptResilient() {
   throw new Error(STOP_ERROR_MESSAGE);
@@ -95,15 +90,41 @@ async function addLog(message, level) {
   logs.push({ message, level });
 }
 
-${bundle}
+${helperBundle}
+${verificationFlowSource}
+
+const helpers = self.MultiPageBackgroundVerificationFlow.createVerificationFlowHelpers({
+  addLog,
+  chrome: {},
+  CLOUDFLARE_TEMP_EMAIL_PROVIDER,
+  completeStepFromBackground: async () => {},
+  confirmCustomVerificationStepBypassRequest: async () => ({ confirmed: true }),
+  getHotmailVerificationPollConfig,
+  getHotmailVerificationRequestTimestamp: () => 123,
+  getState: async () => ({}),
+  getTabId: async () => null,
+  HOTMAIL_PROVIDER,
+  isStopError,
+  LUCKMAIL_PROVIDER,
+  pollCloudflareTempEmailVerificationCode,
+  pollHotmailVerificationCode,
+  pollLuckmailVerificationCode,
+  sendToContentScript: async () => ({}),
+  sendToMailContentScriptResilient,
+  setState: async () => {},
+  setStepStatus: async () => {},
+  sleepWithStop: async () => {},
+  throwIfStopped,
+  VERIFICATION_POLL_MAX_ROUNDS,
+});
 
 return {
-  pollFreshVerificationCode,
+  pollFreshVerificationCode: helpers.pollFreshVerificationCode,
   snapshot() {
     return { logs, resendCalls };
   },
 };
-`)();
+`)(verificationFlowSource);
 
   let error = null;
   try {
@@ -119,56 +140,63 @@ return {
 }
 
 async function testResolveVerificationStepRethrowsStopFromFreshRequest() {
-  const bundle = [
-    extractFunction('isStopError'),
-    extractFunction('resolveVerificationStep'),
+  const helperBundle = [
+    extractFunction(helperSource, 'isStopError'),
   ].join('\n');
 
-const api = new Function(`
+const api = new Function('verificationFlowSource', `
+const self = {};
 const STOP_ERROR_MESSAGE = '流程已被用户停止。';
 const HOTMAIL_PROVIDER = 'hotmail-api';
 const LUCKMAIL_PROVIDER = 'luckmail-api';
 const CLOUDFLARE_TEMP_EMAIL_PROVIDER = 'cloudflare-temp-email';
 const logs = [];
 let pollCalls = 0;
-
-function getVerificationCodeStateKey(step) {
-  return step === 4 ? 'lastSignupCode' : 'lastLoginCode';
-}
-function getHotmailVerificationPollConfig() {
-  return {};
-}
-function getVerificationCodeLabel(step) {
-  return step === 4 ? '注册' : '登录';
-}
-function isStep7RestartFromStep6Error() {
-  return false;
-}
-async function requestVerificationCodeResend() {
-  throw new Error(STOP_ERROR_MESSAGE);
-}
 async function addLog(message, level) {
   logs.push({ message, level });
 }
-async function pollFreshVerificationCode() {
-  pollCalls += 1;
-  return { code: '123456', emailTimestamp: Date.now() };
-}
-async function submitVerificationCode() {
-  throw new Error('submit should not run in this test');
-}
-async function setState() {}
-async function completeStepFromBackground() {}
-
-${bundle}
+const chrome = { tabs: { async update() {} } };
+
+${helperBundle}
+${verificationFlowSource}
+
+const helpers = self.MultiPageBackgroundVerificationFlow.createVerificationFlowHelpers({
+  addLog,
+  chrome,
+  CLOUDFLARE_TEMP_EMAIL_PROVIDER,
+  completeStepFromBackground: async () => {},
+  confirmCustomVerificationStepBypassRequest: async () => ({ confirmed: true }),
+  getHotmailVerificationPollConfig: () => ({}),
+  getHotmailVerificationRequestTimestamp: () => 123,
+  getState: async () => ({}),
+  getTabId: async () => 1,
+  HOTMAIL_PROVIDER,
+  isStopError,
+  LUCKMAIL_PROVIDER,
+  pollCloudflareTempEmailVerificationCode: async () => ({}),
+  pollHotmailVerificationCode: async () => ({}),
+  pollLuckmailVerificationCode: async () => ({}),
+  sendToContentScript: async () => {
+    throw new Error(STOP_ERROR_MESSAGE);
+  },
+  sendToMailContentScriptResilient: async () => {
+    pollCalls += 1;
+    return {};
+  },
+  setState: async () => {},
+  setStepStatus: async () => {},
+  sleepWithStop: async () => {},
+  throwIfStopped: () => {},
+  VERIFICATION_POLL_MAX_ROUNDS: 5,
+});
 
 return {
-  resolveVerificationStep,
+  resolveVerificationStep: helpers.resolveVerificationStep,
   snapshot() {
     return { logs, pollCalls };
   },
 };
-`)();
+`)(verificationFlowSource);
 
   let error = null;
   try {