// content/mail-2925.js - Content script for 2925 Mail (steps 4, 8)
// Injected dynamically on: 2925.com

const MAIL2925_PREFIX = '[MultiPage:mail-2925]';
const isTopFrame = window === window.top;

console.log(MAIL2925_PREFIX, 'Content script loaded on', location.href, 'frame:', isTopFrame ? 'top' : 'child');

if (!isTopFrame) {
  console.log(MAIL2925_PREFIX, 'Skipping child frame');
} else {

let seenCodes = new Set();
let seenCodeSessionKey = '';
let seenCodesReadyPromise = null;

async function loadSeenCodes() {
  try {
    const data = await chrome.storage.session.get(['seen2925CodeState', 'seen2925Codes']);
    const state = data?.seen2925CodeState || null;
    if (state && typeof state === 'object') {
      seenCodeSessionKey = String(state.sessionKey || '');
      if (Array.isArray(state.codes)) {
        seenCodes = new Set(state.codes);
      }
      console.log(MAIL2925_PREFIX, `Loaded ${seenCodes.size} seen codes for session ${seenCodeSessionKey || 'default'}`);
      return;
    }

    if (data.seen2925Codes && Array.isArray(data.seen2925Codes)) {
      seenCodes = new Set(data.seen2925Codes);
      console.log(MAIL2925_PREFIX, `Loaded ${seenCodes.size} previously seen codes`);
    }
  } catch (err) {
    console.warn(MAIL2925_PREFIX, 'Session storage unavailable, using in-memory seen codes:', err?.message || err);
  }
}

seenCodesReadyPromise = loadSeenCodes();

async function persistSeenCodes() {
  try {
    await chrome.storage.session.set({
      seen2925Codes: [...seenCodes],
      seen2925CodeState: {
        sessionKey: seenCodeSessionKey,
        codes: [...seenCodes],
      },
    });
  } catch (err) {
    console.warn(MAIL2925_PREFIX, 'Could not persist seen codes, continuing in-memory only:', err?.message || err);
  }
}

function buildSeenCodeSessionKey(step, payload = {}) {
  const timestamp = Number(payload?.filterAfterTimestamp);
  if (Number.isFinite(timestamp) && timestamp > 0) {
    return `${step}:${timestamp}`;
  }
  return `${step}:default`;
}

async function ensureSeenCodesSession(step, payload = {}) {
  if (seenCodesReadyPromise) {
    await seenCodesReadyPromise;
    seenCodesReadyPromise = null;
  }

  const nextSessionKey = buildSeenCodeSessionKey(step, payload);
  if (seenCodeSessionKey === nextSessionKey) {
    return;
  }

  seenCodeSessionKey = nextSessionKey;
  seenCodes = new Set();
  await persistSeenCodes();
}

chrome.runtime.onMessage.addListener((message, sender, sendResponse) => {
  if (message.type === 'POLL_EMAIL') {
    resetStopState();
    handlePollEmail(message.step, message.payload).then((result) => {
      sendResponse(result);
    }).catch((err) => {
      if (isStopError(err)) {
        log(`步骤 ${message.step}：已被用户停止。`, 'warn');
        sendResponse({ stopped: true, error: err.message });
        return;
      }

      log(`步骤 ${message.step}：邮箱轮询失败：${err.message}`, 'warn');
      sendResponse({ error: err.message });
    });
    return true;
  }

  if (message.type === 'DELETE_ALL_EMAILS') {
    Promise.resolve(deleteAllMailboxEmails(message.step)).catch(() => {});
    sendResponse({ ok: true });
    return true;
  }

  return false;
});

const MAIL_ITEM_SELECTORS = [
  '.mail-item',
  '.letter-item',
  '[class*="mailItem"]',
  '[class*="mail-item"]',
  '[class*="MailItem"]',
  '.el-table__row',
  'tr[class*="mail"]',
  '[class*="listItem"]',
  '[class*="list-item"]',
  'li[class*="mail"]',
];
const MAIL_ITEM_SELECTOR_GROUP = MAIL_ITEM_SELECTORS.join(', ');
const MAIL_REFRESH_SELECTORS = [
  '[class*="refresh"]',
  '[title*="刷新"]',
  '[aria-label*="刷新"]',
  '[class*="Refresh"]',
];
const MAIL_INBOX_SELECTORS = [
  'a[href*="mailList"]',
  '[class*="inbox"]',
  '[class*="Inbox"]',
  '[title*="收件箱"]',
];
const MAIL_DELETE_SELECTORS = [
  '[class*="delete"]',
  '[title*="删除"]',
  '[aria-label*="删除"]',
  '[class*="Delete"]',
];
const MAIL_SELECT_ALL_SELECTORS = [
  'input[type="checkbox"]',
  '[role="checkbox"]',
  '.el-checkbox__input',
  '.el-checkbox',
  'label[class*="checkbox"]',
  '[class*="checkbox"]',
];
const MAIL_ACTION_CANDIDATE_SELECTORS = 'button, [role="button"], a, label, span, div';

function normalizeNodeText(value) {
  return String(value || '').replace(/\s+/g, ' ').trim();
}

function isVisibleNode(node) {
  if (!node) return false;
  if (node.hidden) return false;

  const style = typeof window.getComputedStyle === 'function'
    ? window.getComputedStyle(node)
    : null;
  if (style && (style.display === 'none' || style.visibility === 'hidden')) {
    return false;
  }

  const rect = typeof node.getBoundingClientRect === 'function'
    ? node.getBoundingClientRect()
    : null;
  if (rect && rect.width <= 0 && rect.height <= 0) {
    return false;
  }

  return true;
}

function isMailItemNode(node) {
  return Boolean(node?.closest?.(MAIL_ITEM_SELECTOR_GROUP));
}

function resolveActionTarget(node) {
  return node?.closest?.('button, [role="button"], a, label, .el-checkbox, .el-checkbox__input') || node || null;
}

function findMailItems() {
  for (const selector of MAIL_ITEM_SELECTORS) {
    const items = document.querySelectorAll(selector);
    if (items.length > 0) {
      return Array.from(items);
    }
  }
  return [];
}

function findActionBySelectors(selectors = []) {
  for (const selector of selectors) {
    const candidates = document.querySelectorAll(selector);
    for (const candidate of candidates) {
      const target = resolveActionTarget(candidate);
      if (!isVisibleNode(target) || isMailItemNode(target)) {
        continue;
      }
      return target;
    }
  }
  return null;
}

function findToolbarActionButton(patterns = [], selectors = []) {
  const directMatch = findActionBySelectors(selectors);
  if (directMatch) {
    return directMatch;
  }

  const candidates = document.querySelectorAll(MAIL_ACTION_CANDIDATE_SELECTORS);
  for (const candidate of candidates) {
    const target = resolveActionTarget(candidate);
    if (!isVisibleNode(target) || isMailItemNode(target)) {
      continue;
    }

    const text = normalizeNodeText(target.innerText || target.textContent || '');
    const label = normalizeNodeText(target.getAttribute?.('aria-label') || target.getAttribute?.('title') || '');
    if (patterns.some((pattern) => pattern.test(text) || pattern.test(label))) {
      return target;
    }
  }

  return null;
}

function findRefreshButton() {
  return findToolbarActionButton([
    /刷新/i,
    /refresh/i,
  ], MAIL_REFRESH_SELECTORS);
}

function findInboxLink() {
  return findActionBySelectors(MAIL_INBOX_SELECTORS);
}

function findDeleteButton() {
  return findToolbarActionButton([
    /删除/i,
    /delete/i,
  ], MAIL_DELETE_SELECTORS);
}

function findSelectAllControl() {
  return findActionBySelectors(MAIL_SELECT_ALL_SELECTORS);
}

function isCheckboxChecked(node) {
  const checkbox = node?.matches?.('input[type="checkbox"], [role="checkbox"]')
    ? node
    : node?.querySelector?.('input[type="checkbox"], [role="checkbox"]');
  if (checkbox?.checked === true) {
    return true;
  }
  if (String(checkbox?.getAttribute?.('aria-checked') || '').toLowerCase() === 'true') {
    return true;
  }
  return Boolean(
    node?.classList?.contains('is-checked')
    || node?.classList?.contains('checked')
  );
}

function getMailItemText(item) {
  if (!item) return '';
  const contentCell = item.querySelector('td.content, .content, .mail-content');
  const titleEl = item.querySelector('.mail-content-title');
  const textEl = item.querySelector('.mail-content-text');
  return [
    titleEl?.getAttribute('title') || '',
    titleEl?.textContent || '',
    textEl?.textContent || '',
    contentCell?.textContent || '',
    item.textContent || '',
  ].join(' ');
}

function getMailItemTimeText(item) {
  const timeEl = item?.querySelector('.date-time-text, [class*="date-time"], [class*="time"], td.time');
  return normalizeNodeText(timeEl?.textContent || '');
}

function normalizeMailIdentityPart(value) {
  return normalizeNodeText(value).toLowerCase();
}

function getMailItemId(item, index = 0) {
  const candidates = [
    item?.getAttribute?.('data-id'),
    item?.dataset?.id,
    item?.getAttribute?.('data-mail-id'),
    item?.dataset?.mailId,
    item?.getAttribute?.('data-key'),
    item?.getAttribute?.('key'),
  ].filter(Boolean);

  if (candidates.length > 0) {
    return String(candidates[0]);
  }

  return [
    index,
    normalizeMailIdentityPart(getMailItemTimeText(item)),
    normalizeMailIdentityPart(getMailItemText(item)).slice(0, 240),
  ].join('|');
}

function getCurrentMailIds(items = []) {
  const ids = new Set();
  items.forEach((item, index) => {
    ids.add(getMailItemId(item, index));
  });
  return ids;
}

function matchesMailFilters(text, senderFilters, subjectFilters) {
  const lower = String(text || '').toLowerCase();
  const senderMatch = senderFilters.some((filter) => lower.includes(String(filter || '').toLowerCase()));
  const subjectMatch = subjectFilters.some((filter) => lower.includes(String(filter || '').toLowerCase()));
  return senderMatch || subjectMatch;
}

function extractVerificationCode(text, strictChatGPTCodeOnly = false) {
  if (strictChatGPTCodeOnly) {
    const strictMatch = String(text || '').match(/your\s+chatgpt\s+code\s+is\s+(\d{6})/i);
    return strictMatch ? strictMatch[1] : null;
  }

  const normalized = String(text || '');

  const matchCn = normalized.match(/(?:代码为|验证码[^0-9]*?)[\s：:]*(\d{6})/);
  if (matchCn) return matchCn[1];

  const matchChatGPT = normalized.match(/your\s+chatgpt\s+code\s+is\s+(\d{6})/i);
  if (matchChatGPT) return matchChatGPT[1];

  const matchEn = normalized.match(/code[:\s]+is[:\s]+(\d{6})|code[:\s]+(\d{6})/i);
  if (matchEn) return matchEn[1] || matchEn[2];

  const match6 = normalized.match(/\b(\d{6})\b/);
  if (match6) return match6[1];

  return null;
}

function parseMailItemTimestamp(item) {
  const timeText = getMailItemTimeText(item);
  if (!timeText) return null;

  const now = new Date();
  const date = new Date(now);
  let match = null;

  if (/刚刚/.test(timeText)) {
    return now.getTime();
  }

  match = timeText.match(/(\d+)\s*分钟前/);
  if (match) {
    return now.getTime() - Number(match[1]) * 60 * 1000;
  }

  match = timeText.match(/(\d+)\s*秒前/);
  if (match) {
    return now.getTime() - Number(match[1]) * 1000;
  }

  match = timeText.match(/^(\d{1,2}):(\d{2})$/);
  if (match) {
    date.setHours(Number(match[1]), Number(match[2]), 0, 0);
    return date.getTime();
  }

  match = timeText.match(/今天\s*(\d{1,2}):(\d{2})/);
  if (match) {
    date.setHours(Number(match[1]), Number(match[2]), 0, 0);
    return date.getTime();
  }

  match = timeText.match(/昨天\s*(\d{1,2}):(\d{2})/);
  if (match) {
    date.setDate(date.getDate() - 1);
    date.setHours(Number(match[1]), Number(match[2]), 0, 0);
    return date.getTime();
  }

  match = timeText.match(/(\d{1,2})-(\d{1,2})\s*(\d{1,2}):(\d{2})/);
  if (match) {
    date.setMonth(Number(match[1]) - 1, Number(match[2]));
    date.setHours(Number(match[3]), Number(match[4]), 0, 0);
    return date.getTime();
  }

  match = timeText.match(/(\d{4})-(\d{1,2})-(\d{1,2})\s*(\d{1,2}):(\d{2})/);
  if (match) {
    return new Date(
      Number(match[1]),
      Number(match[2]) - 1,
      Number(match[3]),
      Number(match[4]),
      Number(match[5]),
      0,
      0
    ).getTime();
  }

  return null;
}

async function sleepRandom(minMs, maxMs = minMs) {
  const duration = Math.floor(Math.random() * (maxMs - minMs + 1)) + minMs;
  await sleep(duration);
}

async function returnToInbox() {
  if (findMailItems().length > 0) {
    return true;
  }

  const inboxLink = findInboxLink();
  if (!inboxLink) {
    return false;
  }

  simulateClick(inboxLink);
  for (let attempt = 0; attempt < 20; attempt += 1) {
    await sleep(250);
    if (findMailItems().length > 0) {
      return true;
    }
  }

  return false;
}

async function openMailAndGetMessageText(item) {
  simulateClick(item);
  try {
    await sleepRandom(1200, 2200);
    return document.body?.textContent || '';
  } finally {
    await returnToInbox();
  }
}

async function deleteCurrentMailboxEmail(step) {
  try {
    const deleteButton = findDeleteButton();
    if (!deleteButton) {
      return false;
    }

    simulateClick(deleteButton);
    await sleepRandom(200, 500);
    return true;
  } catch (err) {
    console.warn(MAIL2925_PREFIX, `Step ${step}: delete-current cleanup failed:`, err?.message || err);
    return false;
  }
}

async function openMailAndDeleteAfterRead(item, step) {
  simulateClick(item);
  try {
    await sleepRandom(1200, 2200);
    return document.body?.textContent || '';
  } finally {
    await deleteCurrentMailboxEmail(step);
    await returnToInbox();
  }
}

async function deleteAllMailboxEmails(step) {
  try {
    await returnToInbox();

    const selectAllControl = findSelectAllControl();
    if (!selectAllControl) {
      return false;
    }

    if (!isCheckboxChecked(selectAllControl)) {
      simulateClick(selectAllControl);
      await sleepRandom(200, 500);
    }

    const deleteButton = findDeleteButton();
    if (!deleteButton) {
      return false;
    }

    simulateClick(deleteButton);
    await sleepRandom(200, 500);
    return true;
  } catch (err) {
    console.warn(MAIL2925_PREFIX, `Step ${step}: delete-all cleanup failed:`, err?.message || err);
    return false;
  }
}

async function refreshInbox() {
  const refreshBtn = findRefreshButton();
  if (refreshBtn) {
    simulateClick(refreshBtn);
    await sleepRandom(700, 1200);
    return;
  }

  const inboxLink = findInboxLink();
  if (inboxLink) {
    simulateClick(inboxLink);
    await sleepRandom(700, 1200);
  }
}

async function handlePollEmail(step, payload) {
  await ensureSeenCodesSession(step, payload);
  const {
    senderFilters,
    subjectFilters,
    maxAttempts,
    intervalMs,
    excludeCodes = [],
    strictChatGPTCodeOnly = false,
  } = payload || {};
  const excludedCodeSet = new Set(excludeCodes.filter(Boolean));

  log(`步骤 ${step}：开始轮询 2925 邮箱（最多 ${maxAttempts} 次）`);

  let initialItems = [];
  let initialLoadUsedRefresh = false;

  for (let i = 0; i < 20; i += 1) {
    initialItems = findMailItems();
    if (initialItems.length > 0) {
      break;
    }
    await sleep(500);
  }

  if (initialItems.length === 0) {
    initialLoadUsedRefresh = true;
    await returnToInbox();
    await refreshInbox();
    await sleep(2000);
    initialItems = findMailItems();
  }

  if (initialItems.length === 0) {
    throw new Error('2925 邮箱列表未加载完成，请确认当前已打开收件箱。');
  }

  const knownMailIds = getCurrentMailIds(initialItems);
  log(`步骤 ${step}：邮件列表已加载，共 ${initialItems.length} 封邮件`);
  log(`步骤 ${step}：已记录当前 ${knownMailIds.size} 封旧邮件快照`);

  const FALLBACK_AFTER = 3;

  for (let attempt = 1; attempt <= maxAttempts; attempt += 1) {
    log(`步骤 ${step}：正在轮询 2925 邮箱，第 ${attempt}/${maxAttempts} 次`);

    if (attempt > 1 || !initialLoadUsedRefresh) {
      await returnToInbox();
      await refreshInbox();
      await sleepRandom(900, 1500);
    }

    const items = findMailItems();
    if (items.length > 0) {
      const useFallback = attempt > FALLBACK_AFTER;
      const newMailIds = new Set();

      items.forEach((item, index) => {
        const itemId = getMailItemId(item, index);
        if (!knownMailIds.has(itemId)) {
          newMailIds.add(itemId);
        }
      });

      for (let index = 0; index < items.length; index += 1) {
        const item = items[index];
        const itemId = getMailItemId(item, index);
        const isNewMail = newMailIds.has(itemId);
        const itemTimestamp = parseMailItemTimestamp(item);

        if (!useFallback && !isNewMail) {
          continue;
        }

        const previewText = getMailItemText(item);
        if (!matchesMailFilters(previewText, senderFilters, subjectFilters)) {
          continue;
        }

        const previewCode = extractVerificationCode(previewText, strictChatGPTCodeOnly);
        const openedText = await openMailAndDeleteAfterRead(item, step);
        const bodyCode = extractVerificationCode(openedText, strictChatGPTCodeOnly);
        const candidateCode = bodyCode || previewCode;

        if (!candidateCode) {
          continue;
        }

        if (excludedCodeSet.has(candidateCode)) {
          log(`步骤 ${step}：跳过排除的验证码：${candidateCode}`, 'info');
          continue;
        }
        if (seenCodes.has(candidateCode)) {
          log(`步骤 ${step}：跳过已处理过的验证码：${candidateCode}`, 'info');
          continue;
        }

        seenCodes.add(candidateCode);
        persistSeenCodes();
        const source = useFallback && !isNewMail
          ? (bodyCode ? '回退匹配邮件正文' : '回退匹配邮件')
          : (bodyCode ? '新邮件正文' : '新邮件');
        const timeLabel = itemTimestamp ? `，时间：${new Date(itemTimestamp).toLocaleString('zh-CN', { hour12: false })}` : '';
        log(`步骤 ${step}：已找到验证码：${candidateCode}（来源：${source}${timeLabel}）`, 'ok');
        return { ok: true, code: candidateCode, emailTimestamp: Date.now() };
      }

      items.forEach((item, index) => {
        knownMailIds.add(getMailItemId(item, index));
      });
    }

    if (attempt === FALLBACK_AFTER + 1) {
      log(`步骤 ${step}：连续 ${FALLBACK_AFTER} 次未发现新邮件，开始回退到首封匹配邮件`, 'warn');
    }

    if (attempt < maxAttempts) {
      await sleepRandom(intervalMs, intervalMs + 1200);
    }
  }

  throw new Error(
    `${(maxAttempts * intervalMs / 1000).toFixed(0)} 秒后仍未在 2925 邮箱中找到新的匹配邮件。请手动检查收件箱。`
  );
}

}