#!/usr/bin/env python3
"""
WeChat 聊天记录搜索工具
用法: python3 search_server.py
访问: http://localhost:5001
"""
import sqlite3, json, os, hashlib, re, time
from http.server import HTTPServer, BaseHTTPRequestHandler
from urllib.parse import urlparse, parse_qs

PORT    = 5001
DB_DIR  = '/Users/yibo/Documents/wechat_plain'
CONTACT_DB = f'{DB_DIR}/contact_contact.db'
SESSION_DB = f'{DB_DIR}/session_session.db'
MSG_DBS = [f'{DB_DIR}/message_message_{i}.db' for i in range(11)
           if os.path.exists(f'{DB_DIR}/message_message_{i}.db')]
MY_IDS  = {15, 543}   # real_sender_id values that mean "sent by me"

TYPE_LABELS = {
    1: '文字', 3: '图片', 34: '语音', 43: '视频', 47: '表情',
    49: '链接/文件', 50: '视频通话', 10000: '系统消息',
    436207665: '红包', 469762048: '转账',
}

# ── Data loading ───────────────────────────────────────────────────────────────
contacts    = {}    # username → {nickname, remark, avatar}
md5_to_user = {}    # md5(username) → username
table_index = {}    # md5(username) → db_path
chat_stats  = {}    # username → {count, last_time, first_time}

def md5(s):
    return hashlib.md5(s.encode()).hexdigest()

def load_contacts():
    try:
        con = sqlite3.connect(CONTACT_DB)
        con.row_factory = sqlite3.Row
        for row in con.execute(
            "SELECT username, nick_name, remark, small_head_url FROM contact WHERE delete_flag=0"
        ):
            u = row['username']
            contacts[u] = {
                'nickname': row['nick_name'] or '',
                'remark':   row['remark']   or '',
                'avatar':   row['small_head_url'] or '',
            }
            md5_to_user[md5(u)] = u
        con.close()
        print(f'[+] {len(contacts)} contacts')
    except Exception as e:
        print(f'[!] contacts: {e}')

def build_index():
    for db_path in MSG_DBS:
        try:
            con = sqlite3.connect(db_path)
            for (t,) in con.execute(
                "SELECT name FROM sqlite_master WHERE type='table' AND name LIKE 'Msg_%'"
            ):
                h = t[4:]
                if h not in table_index:
                    table_index[h] = db_path
            con.close()
        except: pass
    print(f'[+] {len(table_index)} message tables indexed')

def load_chat_stats():
    path = f'{DB_DIR}/chat_stats.json'
    if not os.path.exists(path):
        print('[!] chat_stats.json not found, run build_chat_stats.py first')
        return
    with open(path) as f:
        chat_stats.update(json.load(f))
    print(f'[+] {len(chat_stats)} chat stat entries loaded')

def dname(username):
    if not username: return '未知'
    c = contacts.get(username, {})
    return c.get('remark') or c.get('nickname') or username

def fmt_ts(ts):
    try:
        ts = int(ts)
        if ts > 1e12: ts //= 1000
        return time.strftime('%Y-%m-%d %H:%M', time.localtime(ts))
    except: return ''

def parse_msg(local_type, raw_content, real_sender_id):
    """Return (sender_username_or_empty, clean_text, is_sent_by_me)"""
    is_me = int(real_sender_id or 0) in MY_IDS
    if local_type != 1:
        label = TYPE_LABELS.get(local_type, f'[类型{local_type}]')
        if local_type == 49 and isinstance(raw_content, str):
            m = re.search(r'<title>(.*?)</title>', raw_content, re.S)
            if m: label = f'[链接] {m.group(1)[:60]}'
        return ('', label, is_me)

    if not raw_content:
        return ('', '', is_me)
    if isinstance(raw_content, bytes):
        try: raw_content = raw_content.decode('utf-8', errors='replace')
        except: return ('', '[二进制内容]', is_me)

    # Group/received messages: "username:\ntext"
    if not is_me and ':\n' in raw_content[:100]:
        idx = raw_content.index(':\n')
        sender_name = raw_content[:idx]
        text = raw_content[idx+2:]
        return (sender_name, text, False)

    return ('', raw_content, is_me)

# ── API ────────────────────────────────────────────────────────────────────────

def api_sessions(_p):
    try:
        con = sqlite3.connect(SESSION_DB)
        con.row_factory = sqlite3.Row
        total = con.execute("SELECT count(*) FROM SessionTable WHERE is_hidden=0").fetchone()[0]
        rows  = con.execute(
            "SELECT * FROM SessionTable WHERE is_hidden=0 ORDER BY sort_timestamp DESC LIMIT 500"
        ).fetchall()
        result = []
        for row in rows:
            d = dict(row)
            u = d.get('username', '')
            d['display_name']  = dname(u)
            d['avatar']        = contacts.get(u, {}).get('avatar', '')
            d['last_time_fmt'] = fmt_ts(d.get('last_timestamp') or d.get('sort_timestamp', 0))
            result.append(d)
        con.close()
        return {'total': total, 'sessions': result}
    except Exception as e:
        return {'total': 0, 'sessions': []}

TYPE_FILTERS = {
    'friends':  "local_type=0",
    'contacts': "local_type=1",
    'groups':   "local_type IN (2,3) AND username LIKE '%@chatroom%'",
    'members':  "local_type=3 AND username NOT LIKE '%@chatroom%'",
    'other':    "local_type IN (5,6)",
    'all':      "1=1",
}

def api_stats(_p):
    try:
        con = sqlite3.connect(CONTACT_DB)
        r = con.execute("""
            SELECT
              sum(CASE WHEN local_type=0 THEN 1 ELSE 0 END),
              sum(CASE WHEN local_type=1 THEN 1 ELSE 0 END),
              sum(CASE WHEN local_type IN (2,3) AND username LIKE '%@chatroom%' THEN 1 ELSE 0 END),
              sum(CASE WHEN local_type=3 AND username NOT LIKE '%@chatroom%' THEN 1 ELSE 0 END),
              sum(CASE WHEN local_type IN (5,6) THEN 1 ELSE 0 END)
            FROM contact WHERE delete_flag=0
        """).fetchone()
        con.close()
        return {'friends': r[0], 'contacts': r[1], 'groups': r[2],
                'members': r[3], 'other': r[4]}
    except Exception as e:
        return {'error': str(e)}

def api_contacts(params):
    q        = params.get('q', [''])[0]
    ctype    = params.get('type', ['friends'])[0]
    sort_by  = params.get('sort', ['name'])[0]   # name | count | time
    page     = int(params.get('page', ['1'])[0])
    per_page = int(params.get('per_page', ['200'])[0])

    where = TYPE_FILTERS.get(ctype, TYPE_FILTERS['friends'])

    try:
        con = sqlite3.connect(CONTACT_DB)
        con.row_factory = sqlite3.Row
        base_where = f"delete_flag=0 AND ({where})"

        if q:
            like = f'%{q}%'
            search_cond = ("AND (nick_name LIKE ? OR remark LIKE ? OR username LIKE ? "
                           "OR remark_pin_yin_initial LIKE ? OR pin_yin_initial LIKE ?)")
            rows = con.execute(
                f"""SELECT username, nick_name, remark, small_head_url,
                           remark_pin_yin_initial, pin_yin_initial
                    FROM contact WHERE {base_where} {search_cond}""",
                (like,)*5).fetchall()
        else:
            rows = con.execute(
                f"""SELECT username, nick_name, remark, small_head_url,
                           remark_pin_yin_initial, pin_yin_initial
                    FROM contact WHERE {base_where}""").fetchall()
        con.close()

        items = []
        for row in rows:
            name = row['remark'] or row['nick_name'] or row['username']
            if not name: continue
            py = (row['remark_pin_yin_initial'] if row['remark'] else row['pin_yin_initial']) or ''
            fl = py[0].upper() if py and py[0].isalpha() else '#'
            s = chat_stats.get(row['username'], {})
            items.append({
                'username':     row['username'],
                'display_name': name,
                'avatar':       row['small_head_url'] or '',
                'first_letter': fl,
                'msg_count':    s.get('count', 0),
                'last_time':    s.get('last_time', 0),
                'last_time_fmt': fmt_ts(s['last_time']) if s.get('last_time') else '',
            })

        # Sort
        if sort_by == 'count':
            items.sort(key=lambda x: x['msg_count'], reverse=True)
        elif sort_by == 'time':
            items.sort(key=lambda x: x['last_time'], reverse=True)
        else:
            items.sort(key=lambda x: (x['first_letter'], x['display_name'].lower()))

        total  = len(items)
        offset = (page - 1) * per_page
        page_items = items[offset:offset + per_page]

        return {'total': total, 'page': page, 'per_page': per_page,
                'has_more': offset + len(page_items) < total,
                'sort': sort_by, 'contacts': page_items}
    except Exception as e:
        return {'total': 0, 'contacts': [], 'error': str(e)}

def api_chat(params):
    username = params.get('username', [''])[0]
    page     = int(params.get('page', ['1'])[0])
    limit    = int(params.get('limit', ['50'])[0])
    offset   = (page - 1) * limit
    if not username:
        return {'error': 'username required'}

    h = md5(username)
    tbl = f'Msg_{h}'
    db_path = table_index.get(h)
    if not db_path:
        return {'messages': [], 'total': 0, 'display_name': dname(username)}

    try:
        con = sqlite3.connect(db_path)
        con.row_factory = sqlite3.Row
        total = con.execute(f'SELECT count(*) FROM "{tbl}"').fetchone()[0]
        rows  = con.execute(
            f'SELECT * FROM "{tbl}" ORDER BY create_time DESC LIMIT ? OFFSET ?',
            (limit, offset)
        ).fetchall()
        messages = []
        for row in rows:
            d = dict(row)
            lt = d.get('local_type', 1)
            raw = d.get('message_content', '') or ''
            sid = d.get('real_sender_id', 0)
            sender_raw, text, is_me = parse_msg(lt, raw, sid)
            sender_name = '我' if is_me else (dname(sender_raw) if sender_raw else dname(username))
            messages.append({
                'local_id':    d.get('local_id'),
                'local_type':  lt,
                'create_time': d.get('create_time', 0),
                'time_fmt':    fmt_ts(d.get('create_time', 0)),
                'is_me':       is_me,
                'sender_name': sender_name,
                'text':        text,
                'type_label':  TYPE_LABELS.get(lt, f'[{lt}]'),
            })
        con.close()
        return {
            'username':     username,
            'display_name': dname(username),
            'total':        total,
            'page':         page,
            'messages':     messages,
        }
    except Exception as e:
        return {'error': str(e), 'messages': [], 'total': 0}

def api_search(params):
    q     = params.get('q', [''])[0]
    limit = int(params.get('limit', ['60'])[0])
    if len(q) < 1:
        return {'results': [], 'count': 0}

    results = []
    for db_path in MSG_DBS:
        try:
            con = sqlite3.connect(db_path)
            con.row_factory = sqlite3.Row
            tables = [r[0] for r in con.execute(
                "SELECT name FROM sqlite_master WHERE type='table' AND name LIKE 'Msg_%'"
            )]
            for tbl in tables:
                try:
                    rows = con.execute(
                        f'SELECT * FROM "{tbl}" WHERE local_type=1 '
                        f'AND message_content LIKE ? ORDER BY create_time DESC LIMIT 5',
                        (f'%{q}%',)
                    ).fetchall()
                    h = tbl[4:]
                    chat_user = md5_to_user.get(h, '')
                    for row in rows:
                        d = dict(row)
                        lt  = d.get('local_type', 1)
                        raw = d.get('message_content', '') or ''
                        sid = d.get('real_sender_id', 0)
                        sender_raw, text, is_me = parse_msg(lt, raw, sid)
                        results.append({
                            'local_id':       d.get('local_id'),
                            'create_time':    d.get('create_time', 0),
                            'time_fmt':       fmt_ts(d.get('create_time', 0)),
                            'is_me':          is_me,
                            'sender_name':    '我' if is_me else (dname(sender_raw) if sender_raw else dname(chat_user)),
                            'chat_username':  chat_user,
                            'chat_name':      dname(chat_user) if chat_user else tbl,
                            'text':           text,
                        })
                except: pass
            con.close()
        except: pass
        if len(results) >= limit * 2: break

    results.sort(key=lambda x: x.get('create_time', 0), reverse=True)
    return {'query': q, 'count': len(results[:limit]), 'results': results[:limit]}

# ── HTML ───────────────────────────────────────────────────────────────────────
HTML = r"""<!DOCTYPE html>
<html lang="zh">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width,initial-scale=1">
<title>微信聊天记录</title>
<style>
*{box-sizing:border-box;margin:0;padding:0}
body{font-family:-apple-system,"PingFang SC","SF Pro Text",sans-serif;background:#0d1117;color:#e6edf3;height:100vh;display:flex;flex-direction:column;overflow:hidden}
::-webkit-scrollbar{width:4px;height:4px}
::-webkit-scrollbar-track{background:transparent}
::-webkit-scrollbar-thumb{background:#30363d;border-radius:2px}

/* top bar */
#topbar{display:flex;align-items:center;gap:12px;padding:10px 16px;background:#161b22;border-bottom:1px solid #21262d;flex-shrink:0}
#topbar h1{font-size:15px;font-weight:600;color:#58a6ff;white-space:nowrap}
#search-global{flex:1;background:#21262d;border:1px solid #30363d;border-radius:8px;padding:7px 14px;color:#e6edf3;font-size:14px;outline:none}
#search-global:focus{border-color:#58a6ff}
#search-global::placeholder{color:#6e7681}
#search-btn{background:#238636;color:#fff;border:none;border-radius:8px;padding:7px 14px;cursor:pointer;font-size:13px;white-space:nowrap}
#search-btn:hover{background:#2ea043}

/* main layout */
#main{display:flex;flex:1;overflow:hidden}

/* sidebar */
#sidebar{width:280px;flex-shrink:0;background:#161b22;border-right:1px solid #21262d;display:flex;flex-direction:column;overflow:hidden}
#sidebar-tabs{display:flex;border-bottom:1px solid #21262d;flex-shrink:0}
.tab{flex:1;padding:10px;text-align:center;font-size:13px;cursor:pointer;color:#6e7681;border-bottom:2px solid transparent;transition:.15s}
.tab.active{color:#58a6ff;border-bottom-color:#58a6ff}
.subtab{display:inline-block;padding:7px 10px;font-size:12px;cursor:pointer;color:#6e7681;border-bottom:2px solid transparent;transition:.15s;white-space:nowrap}
.subtab.active{color:#58a6ff;border-bottom-color:#58a6ff}
.tab-cnt{font-size:10px;color:#8b949e;margin-left:2px}
.sort-btn{background:transparent;border:1px solid #30363d;border-radius:4px;color:#8b949e;font-size:11px;padding:2px 7px;cursor:pointer;transition:.15s}
.sort-btn:hover{border-color:#58a6ff;color:#58a6ff}
.sort-btn.active{border-color:#58a6ff;color:#58a6ff;background:#1c2128}
.item-count{font-size:10px;color:#6e7681;white-space:nowrap;flex-shrink:0;text-align:right}
#list{flex:1;overflow-y:auto}
.list-item{display:flex;align-items:center;gap:10px;padding:10px 14px;cursor:pointer;border-bottom:1px solid #1c2128;transition:.1s}
.list-item:hover{background:#1c2128}
.list-item.active{background:#1f2937;border-left:3px solid #58a6ff}
.avatar{width:40px;height:40px;border-radius:50%;background:#238636;display:flex;align-items:center;justify-content:center;font-size:16px;flex-shrink:0;overflow:hidden;color:#fff}
.avatar img{width:100%;height:100%;object-fit:cover}
.item-info{flex:1;min-width:0}
.item-name{font-size:13px;font-weight:500;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;color:#e6edf3}
.item-sub{font-size:11px;color:#6e7681;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;margin-top:2px}
.badge{background:#fa4d56;color:#fff;border-radius:10px;font-size:10px;padding:1px 5px;flex-shrink:0}

/* chat panel */
#chat{flex:1;display:flex;flex-direction:column;overflow:hidden}
#chat-header{padding:12px 20px;background:#161b22;border-bottom:1px solid #21262d;flex-shrink:0;display:flex;align-items:center;justify-content:space-between}
#chat-header h2{font-size:15px;font-weight:600}
#chat-meta{font-size:12px;color:#6e7681}
#messages{flex:1;overflow-y:auto;padding:16px;display:flex;flex-direction:column;gap:12px}
#load-more{text-align:center;padding:8px;flex-shrink:0}
#load-more button{background:#21262d;border:1px solid #30363d;color:#8b949e;border-radius:6px;padding:6px 16px;cursor:pointer;font-size:12px}
#load-more button:hover{background:#30363d}

/* message bubbles */
.msg{display:flex;gap:8px;max-width:75%}
.msg.sent{align-self:flex-end;flex-direction:row-reverse}
.msg.received{align-self:flex-start}
.msg-avatar{width:32px;height:32px;border-radius:50%;background:#1f6feb;display:flex;align-items:center;justify-content:center;font-size:13px;flex-shrink:0;color:#fff;overflow:hidden}
.msg-avatar img{width:100%;height:100%;object-fit:cover}
.msg-body{display:flex;flex-direction:column;gap:3px}
.msg-sender{font-size:11px;color:#6e7681}
.msg.sent .msg-sender{text-align:right}
.bubble{padding:9px 13px;border-radius:12px;font-size:14px;line-height:1.5;word-break:break-word;white-space:pre-wrap}
.msg.received .bubble{background:#21262d;border-radius:2px 12px 12px 12px;color:#e6edf3}
.msg.sent .bubble{background:#1a7f37;border-radius:12px 2px 12px 12px;color:#fff}
.bubble.media{color:#8b949e;font-style:italic}
.msg-time{font-size:10px;color:#6e7681}
.msg.sent .msg-time{text-align:right}

/* search results */
#search-results{flex:1;overflow-y:auto;padding:16px;display:flex;flex-direction:column;gap:8px}
.sr-item{background:#161b22;border:1px solid #21262d;border-radius:8px;padding:12px 14px;cursor:pointer;transition:.15s}
.sr-item:hover{border-color:#58a6ff;background:#1c2128}
.sr-meta{display:flex;justify-content:space-between;font-size:11px;color:#6e7681;margin-bottom:6px}
.sr-chat{color:#58a6ff;font-weight:500}
.sr-text{font-size:13px;color:#e6edf3;white-space:pre-wrap;word-break:break-word}
.sr-text mark{background:#3d2b1f;color:#ffa657;border-radius:2px;padding:0 2px}
.letter-header{padding:4px 14px;font-size:11px;font-weight:600;color:#58a6ff;background:#0d1117;position:sticky;top:0;z-index:1;border-bottom:1px solid #21262d}
.empty{color:#6e7681;font-size:13px;text-align:center;margin-top:60px}
#loading{color:#6e7681;font-size:13px;text-align:center;margin-top:20px}
</style>
</head>
<body>
<div id="topbar">
  <h1>📱 微信聊天记录</h1>
  <input id="search-global" type="text" placeholder="搜索消息内容..." onkeydown="if(event.key==='Enter')doSearch()">
  <button id="search-btn" onclick="doSearch()">搜索</button>
</div>
<div id="main">
  <div id="sidebar">
    <div id="sidebar-tabs">
      <div class="tab active" onclick="switchMainTab('sessions')">会话</div>
      <div class="tab" onclick="switchMainTab('contacts')">联系人</div>
    </div>
    <!-- contact sub-tabs, shown only when contacts main tab is active -->
    <div id="contact-subtabs" style="display:none;flex-shrink:0;border-bottom:1px solid #21262d;overflow-x:auto;white-space:nowrap">
      <div class="subtab active" data-type="friends"  onclick="switchContactType(this,'friends')">好友<span class="tab-cnt" id="cnt-friends"></span></div>
      <div class="subtab"        data-type="contacts" onclick="switchContactType(this,'contacts')">联系人<span class="tab-cnt" id="cnt-contacts"></span></div>
      <div class="subtab"        data-type="groups"   onclick="switchContactType(this,'groups')">群聊<span class="tab-cnt" id="cnt-groups"></span></div>
      <div class="subtab"        data-type="members"  onclick="switchContactType(this,'members')">群成员<span class="tab-cnt" id="cnt-members"></span></div>
      <div class="subtab"        data-type="other"    onclick="switchContactType(this,'other')">其他<span class="tab-cnt" id="cnt-other"></span></div>
    </div>
    <div id="list-header" style="padding:5px 10px 4px;font-size:11px;color:#6e7681;flex-shrink:0;background:#161b22;display:flex;align-items:center;gap:6px;flex-wrap:wrap">
      <span id="list-header-text" style="flex:1;min-width:0"></span>
      <span id="sort-btns" style="display:none;gap:3px;display:none">
        <button class="sort-btn active" data-sort="name"  onclick="setSort('name')">名字</button>
        <button class="sort-btn"        data-sort="count" onclick="setSort('count')">消息数</button>
        <button class="sort-btn"        data-sort="time"  onclick="setSort('time')">最近</button>
      </span>
      <input id="contact-q" placeholder="搜索..." oninput="searchContacts(this.value)"
             style="display:none;width:100px;background:#21262d;border:1px solid #30363d;border-radius:5px;padding:3px 8px;color:#e6edf3;font-size:12px;outline:none">
    </div>
    <div id="list"><div class="empty">加载中...</div></div>
    <div id="list-more" style="display:none;text-align:center;padding:6px;flex-shrink:0">
      <button onclick="loadMoreContacts()" style="background:#21262d;border:1px solid #30363d;color:#8b949e;border-radius:6px;padding:5px 14px;cursor:pointer;font-size:12px">加载更多</button>
    </div>
  </div>
  <div id="chat">
    <div id="chat-header">
      <h2 id="chat-title">选择一个会话</h2>
      <span id="chat-meta"></span>
    </div>
    <div id="messages"><div class="empty">← 从左侧选择会话，或在顶部搜索消息</div></div>
    <div id="load-more" style="display:none">
      <button onclick="loadMore()">加载更早的消息</button>
    </div>
  </div>
</div>
<script>
let currentTab = 'sessions';
let currentUsername = '';
let currentPage = 1;
let currentTotal = 0;
let isSearchMode = false;
let currentContactType = 'friends';
let currentContactPage = 1;
let currentSort = 'name';
let contactQ = '';
let contactHasMore = false;
let contactTimer;

// ── Main tab switching ────────────────────────────────────────────────────────
function switchMainTab(tab) {
  currentTab = tab;
  document.querySelectorAll('#sidebar-tabs .tab').forEach((t, i) =>
    t.classList.toggle('active', i === (tab === 'sessions' ? 0 : 1)));
  const showContacts = tab === 'contacts';
  document.getElementById('contact-subtabs').style.display = showContacts ? 'flex' : 'none';
  document.getElementById('sort-btns').style.display = showContacts ? 'flex' : 'none';
  document.getElementById('contact-q').style.display = showContacts ? 'inline-block' : 'none';
  if (!showContacts) {
    document.getElementById('list-header-text').textContent = '';
    document.getElementById('list-more').style.display = 'none';
    loadSessions();
  } else {
    loadStats();
    loadContactsPage(currentContactType, '', 1, true);
  }
}

function switchContactType(el, type) {
  currentContactType = type;
  document.querySelectorAll('.subtab').forEach(t => t.classList.remove('active'));
  el.classList.add('active');
  document.getElementById('contact-q').value = '';
  contactQ = '';
  loadContactsPage(type, '', 1, true);
}

function setSort(sort) {
  currentSort = sort;
  document.querySelectorAll('.sort-btn').forEach(b =>
    b.classList.toggle('active', b.dataset.sort === sort));
  loadContactsPage(currentContactType, contactQ, 1, true);
}

async function loadStats() {
  try {
    const d = await fetch('/api/stats').then(r => r.json());
    const map = {friends:'cnt-friends', contacts:'cnt-contacts', groups:'cnt-groups',
                 members:'cnt-members', other:'cnt-other'};
    Object.entries(map).forEach(([k, id]) => {
      const el = document.getElementById(id);
      if (el && d[k] != null) el.textContent = ' ' + Number(d[k]).toLocaleString();
    });
  } catch(e) {}
}

// ── Sessions ──────────────────────────────────────────────────────────────────
async function loadSessions() {
  const list = document.getElementById('list');
  list.innerHTML = '<div id="loading">加载中...</div>';
  const data = await fetch('/api/sessions').then(r=>r.json());
  list.innerHTML = '';
  const sessions = data.sessions || [];
  document.getElementById('list-header-text').textContent = `${data.total || sessions.length} 个会话`;
  if (!sessions.length) { list.innerHTML = '<div class="empty">无会话</div>'; return; }
  const frag = document.createDocumentFragment();
  sessions.forEach(s => {
    frag.appendChild(makeListItem(s.username, s.display_name, s.avatar,
      s.summary || '', s.last_time_fmt || '', s.unread_count));
  });
  list.appendChild(frag);
}

// ── Contacts ──────────────────────────────────────────────────────────────────
async function loadContactsPage(type, q, page, replace) {
  contactQ = q;
  currentContactPage = page;
  const list = document.getElementById('list');
  if (replace) list.innerHTML = '<div id="loading">加载中...</div>';
  const url = `/api/contacts?type=${encodeURIComponent(type)}&q=${encodeURIComponent(q)}&sort=${currentSort}&page=${page}&per_page=200`;
  const data = await fetch(url).then(r => r.json());
  if (replace) list.innerHTML = '';

  const items = data.contacts || [];
  if (replace && !items.length) {
    list.innerHTML = '<div class="empty">无结果</div>';
    document.getElementById('list-more').style.display = 'none';
    document.getElementById('list-header-text').textContent = q ? '找到 0 个' : '共 0 个';
    return;
  }

  document.getElementById('list-header-text').textContent =
    q ? `找到 ${data.total} 个` : `共 ${data.total} 个`;

  const byName = currentSort === 'name';
  const frag = document.createDocumentFragment();
  let lastLetter = null;
  items.forEach(c => {
    if (byName && c.first_letter !== lastLetter) {
      lastLetter = c.first_letter;
      const hdr = document.createElement('div');
      hdr.className = 'letter-header';
      hdr.textContent = c.first_letter;
      frag.appendChild(hdr);
    }
    frag.appendChild(makeContactItem(c));
  });
  list.appendChild(frag);

  contactHasMore = !!data.has_more;
  document.getElementById('list-more').style.display = contactHasMore ? 'block' : 'none';
}

function loadMoreContacts() {
  loadContactsPage(currentContactType, contactQ, currentContactPage + 1, false);
}

function searchContacts(q) {
  clearTimeout(contactTimer);
  contactTimer = setTimeout(() => loadContactsPage(currentContactType, q, 1, true), 300);
}

// ── List item builder ─────────────────────────────────────────────────────────
function makeListItem(username, name, avatar, sub, timeStr, unread) {
  const div = document.createElement('div');
  div.className = 'list-item';
  div.dataset.username = username;
  const initial = name ? name[0] : '?';
  const avatarHtml = avatar
    ? `<img src="${avatar}" onerror="this.parentNode.textContent='${initial}'">`
    : initial;
  div.innerHTML = `
    <div class="avatar">${avatarHtml}</div>
    <div class="item-info">
      <div class="item-name">${esc(name)}</div>
      <div class="item-sub">${timeStr ? '<span style="color:#6e7681">'+timeStr+'</span> ' : ''}${esc(sub)}</div>
    </div>
    ${unread ? `<span class="badge">${unread}</span>` : ''}
  `;
  div.onclick = () => openChat(username, name);
  return div;
}

// ── Contact item (with msg count badge) ──────────────────────────────────────
function makeContactItem(c) {
  const div = document.createElement('div');
  div.className = 'list-item';
  div.dataset.username = c.username;
  const initial = c.display_name ? c.display_name[0] : '?';
  const avatarHtml = c.avatar
    ? `<img src="${c.avatar}" onerror="this.parentNode.textContent='${initial}'">`
    : initial;
  let countTxt = '';
  if (c.msg_count) {
    const n = c.msg_count >= 10000
      ? (c.msg_count / 10000).toFixed(1) + '万'
      : c.msg_count.toString();
    countTxt = `<div class="item-count">${n}<br><span style="font-size:9px">条</span></div>`;
  }
  const sub = (currentSort === 'time' && c.last_time_fmt) ? c.last_time_fmt : '';
  div.innerHTML = `
    <div class="avatar">${avatarHtml}</div>
    <div class="item-info">
      <div class="item-name">${esc(c.display_name)}</div>
      ${sub ? `<div class="item-sub">${esc(sub)}</div>` : ''}
    </div>
    ${countTxt}
  `;
  div.onclick = () => openChat(c.username, c.display_name);
  return div;
}

// ── Open chat ─────────────────────────────────────────────────────────────────
async function openChat(username, name) {
  isSearchMode = false;
  currentUsername = username;
  currentPage = 1;
  document.querySelectorAll('.list-item').forEach(el =>
    el.classList.toggle('active', el.dataset.username === username));
  document.getElementById('chat-title').textContent = name || username;
  document.getElementById('chat-meta').textContent = '';
  document.getElementById('messages').innerHTML = '<div id="loading">加载中...</div>';
  document.getElementById('load-more').style.display = 'none';
  await loadMessages(username, 1, true);
}

async function loadMessages(username, page, replace) {
  const data = await fetch(`/api/chat?username=${encodeURIComponent(username)}&page=${page}&limit=50`).then(r=>r.json());
  if (data.error && !data.messages) {
    document.getElementById('messages').innerHTML = `<div class="empty">${data.error}</div>`;
    return;
  }
  currentTotal = data.total || 0;
  document.getElementById('chat-meta').textContent = `共 ${currentTotal} 条消息`;

  const msgs = (data.messages || []).reverse();  // oldest first
  const container = document.getElementById('messages');

  if (replace) {
    container.innerHTML = '';
    if (!msgs.length) { container.innerHTML = '<div class="empty">无消息</div>'; return; }
  }

  const frag = document.createDocumentFragment();
  msgs.forEach(m => frag.appendChild(buildBubble(m)));

  if (replace) {
    container.appendChild(frag);
    container.scrollTop = container.scrollHeight;
  } else {
    const prevH = container.scrollHeight;
    container.insertBefore(frag, container.firstChild);
    container.scrollTop = container.scrollHeight - prevH;
  }

  const loaded = page * 50;
  const lm = document.getElementById('load-more');
  lm.style.display = loaded < currentTotal ? 'block' : 'none';
}

function loadMore() {
  currentPage++;
  loadMessages(currentUsername, currentPage, false);
}

function buildBubble(m) {
  const div = document.createElement('div');
  div.className = 'msg ' + (m.is_me ? 'sent' : 'received');
  const initial = m.sender_name ? m.sender_name[0] : '?';
  const isMedia = m.local_type !== 1;
  div.innerHTML = `
    <div class="msg-avatar">${initial}</div>
    <div class="msg-body">
      <div class="msg-sender">${esc(m.sender_name)}</div>
      <div class="bubble${isMedia?' media':''}">${esc(m.text || m.type_label)}</div>
      <div class="msg-time">${m.time_fmt}</div>
    </div>
  `;
  return div;
}

// ── Search ────────────────────────────────────────────────────────────────────
async function doSearch() {
  const q = document.getElementById('search-global').value.trim();
  if (!q) { if (currentUsername) return; loadSessions(); return; }
  isSearchMode = true;
  document.getElementById('load-more').style.display = 'none';
  document.getElementById('chat-title').textContent = `搜索: ${q}`;
  document.getElementById('chat-meta').textContent = '';

  const msgArea = document.getElementById('messages');
  msgArea.innerHTML = '<div id="loading">搜索中...</div>';

  const data = await fetch('/api/search?q='+encodeURIComponent(q)+'&limit=60').then(r=>r.json());
  msgArea.innerHTML = '';

  if (!data.results || !data.results.length) {
    msgArea.innerHTML = '<div class="empty">无结果</div>'; return;
  }
  document.getElementById('chat-meta').textContent = `找到 ${data.count} 条`;

  const frag = document.createDocumentFragment();
  data.results.forEach(r => {
    const div = document.createElement('div');
    div.className = 'sr-item';
    div.innerHTML = `
      <div class="sr-meta">
        <span class="sr-chat">${esc(r.chat_name)}</span>
        <span>${r.time_fmt} · ${esc(r.sender_name)}</span>
      </div>
      <div class="sr-text">${highlight(r.text || '', q)}</div>
    `;
    if (r.chat_username) div.onclick = () => openChat(r.chat_username, r.chat_name);
    frag.appendChild(div);
  });
  msgArea.appendChild(frag);
}

function highlight(text, q) {
  return esc(text).replace(new RegExp(escRe(esc(q)), 'gi'), m => `<mark>${m}</mark>`);
}
function escRe(s) { return s.replace(/[.*+?^${}()|[\]\\]/g, '\\$&'); }
function esc(s) {
  if (!s) return '';
  return String(s).replace(/&/g,'&amp;').replace(/</g,'&lt;').replace(/>/g,'&gt;').replace(/"/g,'&quot;');
}

// ── Init ──────────────────────────────────────────────────────────────────────
switchMainTab('sessions');
</script>
</body>
</html>"""

# ── HTTP handler ───────────────────────────────────────────────────────────────
ROUTES = {
    '/api/sessions':  lambda p: api_sessions(p),
    '/api/contacts':  api_contacts,
    '/api/stats':     api_stats,
    '/api/chat':      api_chat,
    '/api/search':    api_search,
}

class Handler(BaseHTTPRequestHandler):
    def do_GET(self):
        parsed = urlparse(self.path)
        params = parse_qs(parsed.query)
        if parsed.path in ('/', '/index.html'):
            body = HTML.encode('utf-8')
            self.send_response(200)
            self.send_header('Content-Type', 'text/html; charset=utf-8')
            self.end_headers()
            self.wfile.write(body)
        elif parsed.path in ROUTES:
            try:    data = ROUTES[parsed.path](params)
            except Exception as e: data = {'error': str(e)}
            body = json.dumps(data, ensure_ascii=False, default=str).encode('utf-8')
            self.send_response(200)
            self.send_header('Content-Type', 'application/json; charset=utf-8')
            self.send_header('Access-Control-Allow-Origin', '*')
            self.end_headers()
            self.wfile.write(body)
        else:
            self.send_response(404); self.end_headers()

    def log_message(self, fmt, *args):
        print(f'  {args[1]} {args[0]}')

if __name__ == '__main__':
    print('=' * 50)
    print('WeChat 聊天记录搜索工具')
    print('=' * 50)
    load_contacts()
    build_index()
    load_chat_stats()
    print(f'\n[*] 启动服务: http://localhost:{PORT}')
    print('    Ctrl+C 停止\n')
    HTTPServer(('localhost', PORT), Handler).serve_forever()