// ==UserScript==
// @name         DeepSeek 消息真实时间戳
// @namespace    https://github.com/miaomiaolu966
// @version      0.7.2
// @description  给 DeepSeek 每条消息加真实发送时间（微信风格）。直接读浏览器本地 IndexedDB 拿逐条 inserted_at，不再回退成"现在"。
// @author       喵喵露, WorkBuddy
// @icon         https://www.deepseek.com/favicon.ico
// @match        https://chat.deepseek.com/*
// @run-at       document-start
// @grant        none
// @license      MIT
// ==/UserScript==
 
(function () {
  'use strict';
 
  // ================== 配置 ==================
  const CFG = {
    rowSelector: '[data-virtual-list-item-key]',
    stampClass: 'ds-ts',
    debug: false,
    DB_NAME: 'deepseek-chat',     // 来自 DeepSeek 网页源码：indexedDB.open("deepseek-chat",1)
    DB_VERSION: 1,
    STORE: 'history-message',     // object store 名称
    netFallback: true,            // IDB 取不到时，回退到独立完整 history_messages 请求
  };
  // ==========================================
 
  // 先解释给用户：这里的"客户端"就是你的浏览器。DeepSeek 网页把历史对话
  // 存进浏览器自带的 IndexedDB 本地数据库（库名 deepseek-chat），所以你重开
  // 对话时根本不用重新下载就能显示历史——真实时间就安静躺在那个本地库里。
 
  const style = document.createElement('style');
  style.textContent = `
    .${CFG.stampClass} {
      font-size: 11px;
      color: #9aa0a6;
      text-align: center;
      margin: 6px 4px 2px;
      line-height: 1.4;
      font-family: system-ui, -apple-system, "Segoe UI", sans-serif;
      user-select: text;
      pointer-events: auto;
    }
    .${CFG.stampClass}.bot {
      display: inline-flex;
      align-items: center;
      margin: 0 8px 0 2px;
      text-align: left;
    }
    .${CFG.stampClass}.pending { color: #5f6368; opacity: .55; }
  `;
 
  const log = (...a) => { if (CFG.debug) console.log('[DS时间戳]', ...a); };
  const info = (...a) => console.info('[DS时间戳]', ...a);
 
  // ---------- 时间格式化（微信风格） ----------
  function fmt(d) {
    const p = (n) => String(n).padStart(2, '0');
    const now = new Date();
    const hm = `${p(d.getHours())}:${p(d.getMinutes())}`;
    const same = (x) => d.getFullYear() === x.getFullYear() && d.getMonth() === x.getMonth() && d.getDate() === x.getDate();
    if (same(now)) return hm;
    const y = new Date(now); y.setDate(now.getDate() - 1);
    if (same(y)) return `昨天 ${hm}`;
    if (d.getFullYear() === now.getFullYear()) return `${p(d.getMonth() + 1)}-${p(d.getDate())} ${hm}`;
    return `${d.getFullYear()}-${p(d.getMonth() + 1)}-${p(d.getDate())} ${hm}`;
  }
 
  function toMs(v) {
    if (typeof v === 'number' && isFinite(v)) return v > 1e12 ? v : v * 1000;
    if (typeof v === 'string' && /^\d+(\.\d+)?$/.test(v.trim())) {
      const n = Number(v.trim()); return n > 1e12 ? n : n * 1000;
    }
    return 0;
  }
 
  // ---------- 状态 ----------
  const MSG_MAP = new Map();   // 消息id(Number) -> {date:Date, role:string}
  let curSession = null;
  let loaded = false;
  let busy = false;
  let refreshTimer = null;
  let dbPromise = null;
 
  // ---------- 会话 id ----------
  function sessionOf() {
    const m = location.pathname.match(/\/a\/chat\/s\/([^/?#]+)/i);
    return m ? m[1] : null;
  }
 
  // ---------- IndexedDB 读取（主路径） ----------
  function openDB() {
    if (dbPromise) return dbPromise;
    dbPromise = new Promise((resolve, reject) => {
      try {
        const req = indexedDB.open(CFG.DB_NAME, CFG.DB_VERSION);
        req.onsuccess = () => resolve(req.result);
        req.onerror = () => reject(req.error);
        // 只读打开，绝不触发 upgradeneeded，避免误改库结构
      } catch (e) { reject(e); }
    });
    return dbPromise;
  }
 
  // 返回某会话的消息数组（来自本地缓存），可能为空
  async function readIdb(sessionId) {
    try {
      const db = await openDB();
      return await new Promise((resolve) => {
        let out = null;
        try {
          const tx = db.transaction(CFG.STORE, 'readonly');
          const store = tx.objectStore(CFG.STORE);
          const req = store.getAll();
          req.onsuccess = () => {
            const recs = req.result || [];
            // 匹配当前会话：优先 record.key，其次 record.data.chat_session.id
            let rec = recs.find((r) => r && r.key === sessionId)
                   || recs.find((r) => r && r.data && r.data.chat_session && r.data.chat_session.id === sessionId);
            if (rec) {
              const cm = (rec.data && rec.data.chat_messages) || rec.chat_messages;
              if (Array.isArray(cm)) out = cm;
            }
            resolve(out);
          };
          req.onerror = () => resolve(null);
        } catch (e) { resolve(null); }
      });
    } catch (e) {
      log('IDB 打开失败，走网络兜底', e.message);
      return null;
    }
  }
 
  // ---------- 写入 MSG_MAP ----------
  function addMessage(m) {
    if (!m) return false;
    const id = (m.message_id != null) ? m.message_id : m.id;
    if (id == null) return false;
    const t = toMs(m.inserted_at != null ? m.inserted_at : m.insertedAt);
    if (!t) return false;
    MSG_MAP.set(Number(id), {
      date: new Date(t),
      role: (m.role || m.author_role || m.sender || ''),
    });
    return true;
  }
 
  function ingestArray(arr) {
    if (!Array.isArray(arr)) return 0;
    let got = 0;
    for (const m of arr) if (addMessage(m)) got++;
    return got;
  }
 
  function ingestNet(json) {
    try {
      const biz = json && json.data && json.data.biz_data;
      const arr = biz && biz.chat_messages;
      return ingestArray(Array.isArray(arr) ? arr : null);
    } catch (e) { return 0; }
  }
 
  // ---------- 网络兜底：独立完整 history_messages（去掉 cache 参数） ----------
  async function loadFullNet(sessionId, withCache0) {
    if (!sessionId || !CFG.netFallback) return 0;
    try {
      let url = `/api/v0/chat/history_messages?chat_session_id=${encodeURIComponent(sessionId)}`;
      if (withCache0) url += '&cache_version=0&cache_reset_at=0';
      const r = await fetch(url, { method: 'GET', credentials: 'include', headers: { accept: 'application/json' } });
      const j = await r.json();
      const got = ingestNet(j);
      if (got === 0 && !withCache0) return await loadFullNet(sessionId, true);
      return got;
    } catch (e) { log('网络兜底失败', e.message); return 0; }
  }
 
  // ---------- 加载当前会话 ----------
  async function loadSession(sessionId) {
    if (!sessionId || busy) return;
    busy = true;
    try {
      const msgs = await readIdb(sessionId);
      let got = ingestArray(msgs || []);
      if (got > 0) {
        loaded = true;
        info(`已从浏览器本地库(IndexedDB)载入真实时间 ${got} 条`);
      } else if (CFG.netFallback) {
        const n = await loadFullNet(sessionId, false);
        if (n > 0) { loaded = true; info(`本地库为空，已通过网络兜底载入 ${n} 条`); }
        else info('该会话在本浏览器暂无缓存，也没拿到网络数据（可能从未在此浏览器打开过）');
      }
    } catch (e) { log('loadSession 出错', e.message); }
    finally {
      busy = false;
      schedule();
    }
  }
 
  // ---------- 收割应用自身的响应（新鲜首次加载时可能含完整 chat_messages） ----------
  function harvest(text) {
    try {
      const j = JSON.parse(text);
      const biz = j && j.data && j.data.biz_data;
      const arr = biz && biz.chat_messages;
      if (Array.isArray(arr) && arr.length) {
        const got = ingestNet(j);
        if (got) { loaded = true; info(`从接口响应补充载入 ${got} 条`); schedule(); }
      }
    } catch (e) { /* 无关响应，忽略 */ }
  }
  const origFetch = window.fetch;
  window.fetch = function (...args) {
    const url = args[0] && (typeof args[0] === 'string' ? args[0] : args[0].url) || '';
    return origFetch.apply(this, args).then((resp) => {
      if (typeof url === 'string' && url.includes('/api/v0/chat/history_messages')) {
        resp.clone().text().then(harvest).catch(() => {});
      }
      return resp;
    });
  };
  const origOpen = XMLHttpRequest.prototype.open;
  XMLHttpRequest.prototype.open = function (m, u) { this.__url = u; return origOpen.apply(this, arguments); };
  const origSend = XMLHttpRequest.prototype.send;
  XMLHttpRequest.prototype.send = function () {
    this.addEventListener('load', () => {
      const url = this.__url || '';
      if (typeof url === 'string' && url.includes('/api/v0/chat/history_messages')) harvest(this.responseText);
    });
    return origSend.apply(this, arguments);
  };
 
  // ---------- 渲染 ----------
  function isMsgRow(row) {
    return !!row.querySelector('[class*="message" i], [class*="markdown" i], [class*="bubble" i], [class*="collapsible" i]');
  }
 
  function isBotRole(role) {
    const r = (role || '').toUpperCase();
    return !!r && r !== 'USER';
  }
 
  // 找 AI 回复底部那排操作图标容器（复制/编辑/重新生成/赞/踩/朗读/分享）
  // 特征：行的直接子元素中是 .ds-flex、且内含 >=2 个 role=button 的图标
  function findActionBar(row) {
    const direct = [...row.children].filter((c) => c.classList && c.classList.contains('ds-flex'));
    const cand = direct.filter((c) => c.querySelectorAll('[role="button"]').length >= 2);
    if (cand.length) return cand[cand.length - 1];
    const withBtns = [...row.children].filter((c) => c.querySelector('[role="button"]'));
    return withBtns.length ? withBtns[withBtns.length - 1] : null;
  }
 
  function tagOf(role) {
    const r = (role || '').toUpperCase();
    if (r === 'USER') return ' · 你';
    if (r === 'BOT') return ' · DeepSeek';
    return '';
  }
 
  function renderRow(row) {
    if (!row || !isMsgRow(row)) return;
    const key = row.getAttribute('data-virtual-list-item-key');
    if (key == null) return;
    const id = Number(key);
 
    let el = row.querySelector('.ds-ts');
    const info0 = MSG_MAP.get(id);
 
    if (info0) {
      const isBot = isBotRole(info0.role);
      if (!el) {
        el = document.createElement('div');
        el.className = CFG.stampClass;
      }
      el.textContent = fmt(info0.date) + tagOf(info0.role);
      el.title = info0.date.toLocaleString();
      el.classList.remove('pending');
      if (isBot) {
        el.classList.add('bot');
        const bar = findActionBar(row);
        if (bar) {
          // 塞进图标排里、弹性占位(flex:1)之前，和图标同一行
          const spacer = [...bar.children].find((c) => {
            const s = (c.getAttribute('style') || '');
            return s.includes('flex: 1') || s.includes('flex:1');
          });
          if (spacer) bar.insertBefore(el, spacer);
          else bar.appendChild(el);
        } else {
          row.appendChild(el); // 兜底：图标排还没渲染时先放行尾
        }
      } else {
        el.classList.remove('bot');
        if (el.parentElement !== row || el !== row.firstElementChild) row.insertBefore(el, row.firstChild);
      }
      return;
    }
 
    // 还没有真实时间：放淡占位（默认先放顶部，拿到真实时间后按角色自动挪位）
    if (!el) {
      el = document.createElement('div');
      el.className = CFG.stampClass + ' pending';
      el.textContent = '读取时间…';
      row.insertBefore(el, row.firstChild);
    }
    if (curSession && !busy) scheduleRefresh();
  }
 
  function scan() {
    document.querySelectorAll(CFG.rowSelector).forEach(renderRow);
  }
 
  let pending = false;
  function schedule() {
    if (pending) return;
    pending = true;
    requestAnimationFrame(() => { pending = false; scan(); });
  }
 
  function scheduleRefresh() {
    if (refreshTimer) clearTimeout(refreshTimer);
    refreshTimer = setTimeout(() => { if (curSession && !busy) loadSession(curSession); }, 1500);
  }
 
  // ---------- 会话切换 ----------
  function checkSession() {
    const s = sessionOf();
    if (s === curSession) return;
    curSession = s;
    MSG_MAP.clear();
    loaded = false;
    document.querySelectorAll('.' + CFG.stampClass).forEach((el) => el.remove());
    if (curSession) {
      log('切换会话，已清空缓存并从本地库重新载入');
      loadSession(curSession);
    }
    schedule();
  }
 
  const _push = history.pushState, _rep = history.replaceState;
  history.pushState = function () { _push.apply(this, arguments); checkSession(); };
  history.replaceState = function () { _rep.apply(this, arguments); checkSession(); };
  window.addEventListener('popstate', checkSession);
  setInterval(checkSession, 2000);
 
  // ---------- 启动 ----------
  function start() {
    if (!document.body) { requestAnimationFrame(start); return; }
    (document.head || document.documentElement).appendChild(style);
    checkSession();
    new MutationObserver(schedule).observe(document.body, { childList: true, subtree: true });
    info('脚本已加载。每个对话的真实发送时间来自浏览器本地 IndexedDB（deepseek-chat / history-message）。打开/切换对话即自动标注。');
  }
  start();
})();