Add SNS/image export and GUI contact export

Introduce SNS (朋友圈) and batch image tooling and enhance the GUI export workflow. Added new scripts: decrypt_sns.py (decrypt WeChat SNS cache) and batch_decrypt_images.py (bulk .dat image decrypt). Update build scripts and PyInstaller spec to include the new files. app_gui.py: add contact discovery, contact selection/export options dialog, new buttons (find image key, SNS), orchestrate combined export/voice/SNS tasks via subprocesses and env flags, and auto-run export after decryption. config.py: add output_base_dir, auto-detect WeChat Files path, and expose msgattach/xwechat cache dirs. export_messages.py: switch to output_base_dir, add image resource lookup and .dat locating/decryption helpers, and support environment-driven contact/format/image filters. Misc: update build.bat and packaging datas to include the new modules.

Co-Authored-By: Copilot <198982749+Copilot@users.noreply.github.com>

export_messages.py

@@ -1,6 +1,8 @@
 """导出微信消息记录到 CSV / HTML / JSON
-目录结构: <wechat_base_dir>/export/<display_name>/messages.csv|html|json
+目录结构: <output_base_dir>/<display_name>/messages.csv|html|json
+图片导出: <output_base_dir>/<display_name>/image/<md5>.<ext>
 """
+import base64
 import sqlite3
 import glob
 import hashlib
@@ -8,6 +10,7 @@ import os
 import json
 import csv
 import re
+import struct
 import sys
 import xml.etree.ElementTree as ET
 from datetime import datetime
@@ -23,7 +26,310 @@ from config import load_config
 _cfg = load_config()
 MSG_DB_DIR = os.path.join(_cfg["decrypted_dir"], "message")
 CONTACT_DB_PATH = os.path.join(_cfg["decrypted_dir"], "contact", "contact.db")
-OUTPUT_DIR = os.path.join(_cfg["wechat_base_dir"], "export")
+OUTPUT_DIR = _cfg["output_base_dir"]
+
+# 图片相关配置
+WECHAT_BASE_DIR = _cfg.get("wechat_base_dir", "")
+ATTACH_DIR = os.path.join(WECHAT_BASE_DIR, "msg", "attach") if WECHAT_BASE_DIR else ""
+MSGATTACH_DIR = _cfg.get("msgattach_dir", "")  # WeChat Files/FileStorage/MsgAttach
+IMAGE_AES_KEY = _cfg.get("image_aes_key")
+IMAGE_XOR_KEY = _cfg.get("image_xor_key", 0x88)
+MSG_RESOURCE_DB = os.path.join(_cfg["decrypted_dir"], "message", "message_resource.db")
+
+_CONTACT_FILTER = None
+_filter_raw = os.environ.get("WECHAT_EXPORT_CONTACTS", "").strip()
+if _filter_raw:
+    _CONTACT_FILTER = set(_filter_raw.split(","))
+    print(f"联系人筛选: {len(_CONTACT_FILTER)} 个")
+
+_EXPORT_FORMATS = None
+_formats_raw = os.environ.get("WECHAT_EXPORT_FORMATS", "").strip()
+if _formats_raw:
+    _EXPORT_FORMATS = set(_formats_raw.lower().split(","))
+    print(f"导出格式: {', '.join(sorted(_EXPORT_FORMATS))}")
+
+_EXPORT_IMAGES = os.environ.get("WECHAT_EXPORT_IMAGES", "1").strip() == "1"
+
+
+# ─── 图片解密辅助 ───────────────────────────────────────────────────────────────
+
+def _extract_md5_from_packed_info(blob):
+    """从 message_resource.db 的 packed_info 中提取文件 MD5"""
+    if not blob or not isinstance(blob, bytes):
+        return None
+    marker = b'\x12\x22\x0a\x20'
+    idx = blob.find(marker)
+    if idx >= 0 and idx + len(marker) + 32 <= len(blob):
+        md5_bytes = blob[idx + len(marker): idx + len(marker) + 32]
+        try:
+            md5_str = md5_bytes.decode('ascii')
+            int(md5_str, 16)
+            return md5_str
+        except (UnicodeDecodeError, ValueError):
+            pass
+    hex_chars = set(b'0123456789abcdef')
+    i = 0
+    while i <= len(blob) - 32:
+        if blob[i] in hex_chars:
+            candidate = blob[i:i+32]
+            if all(b in hex_chars for b in candidate):
+                try:
+                    return candidate.decode('ascii')
+                except UnicodeDecodeError:
+                    pass
+            i += 32
+        else:
+            i += 1
+    return None
+
+
+def _load_resource_md5_map():
+    """加载 message_resource.db 的 (chat_username, local_id) -> file_md5 映射"""
+    md5_map = {}
+    if not os.path.exists(MSG_RESOURCE_DB):
+        return md5_map
+    try:
+        conn = sqlite3.connect(MSG_RESOURCE_DB)
+        # chat_id -> username
+        chat_id_map = {}
+        for row in conn.execute("SELECT rowid, user_name FROM ChatName2Id"):
+            chat_id_map[row[0]] = row[1]
+        for row in conn.execute(
+            "SELECT chat_id, message_local_id, packed_info FROM MessageResourceInfo"
+        ):
+            cid, lid, blob = row
+            md5 = _extract_md5_from_packed_info(blob)
+            if md5:
+                uname = chat_id_map.get(cid, "")
+                if uname:
+                    md5_map[(uname, lid)] = md5
+        conn.close()
+        print(f"图片资源映射: {len(md5_map)} 条")
+    except Exception as e:
+        print(f"读取 message_resource.db 失败: {e}")
+    return md5_map
+
+
+def _find_dat_file(username_hash, file_md5):
+    """在 attach / MsgAttach 目录下查找 .dat 文件，优先高清版"""
+    search_patterns = []
+    # xwechat_files 的 msg/attach 目录: <hash>/<YYYY-MM>/Img/<md5>*.dat
+    if ATTACH_DIR and os.path.isdir(ATTACH_DIR):
+        search_base = os.path.join(ATTACH_DIR, username_hash)
+        if os.path.isdir(search_base):
+            search_patterns.append(os.path.join(search_base, "*", "Img", f"{file_md5}*.dat"))
+    # WeChat Files 的 MsgAttach 目录: <hash>/Image/<YYYY-MM>/<md5>*.dat
+    if MSGATTACH_DIR and os.path.isdir(MSGATTACH_DIR):
+        search_base = os.path.join(MSGATTACH_DIR, username_hash)
+        if os.path.isdir(search_base):
+            search_patterns.append(os.path.join(search_base, "Image", "*", f"{file_md5}*.dat"))
+
+    files = []
+    for pat in search_patterns:
+        files.extend(glob.glob(pat))
+    if not files:
+        return None
+    # 优先: 无后缀(原图) > _W(原图) > _h(高清) > _t/_t_W(缩略图)
+    # 先过滤掉缩略图
+    non_thumb = [f for f in files if '_t.' not in os.path.basename(f) and '_t_' not in os.path.basename(f)]
+    candidates = non_thumb if non_thumb else files
+    selected = candidates[0]
+    for f in candidates:
+        fname = os.path.basename(f)
+        # 精确匹配原图（无后缀）
+        if fname == f"{file_md5}.dat":
+            return f
+    for f in candidates:
+        fname = os.path.basename(f)
+        if fname == f"{file_md5}_W.dat":
+            return f
+    for f in candidates:
+        if '_h.' in os.path.basename(f) or '_h_' in os.path.basename(f):
+            return f
+    return selected
+
+
+def _detect_image_format(header):
+    """根据解密后的文件头检测图片格式"""
+    if header[:3] == bytes([0xFF, 0xD8, 0xFF]):
+        return 'jpg'
+    if header[:4] == bytes([0x89, 0x50, 0x4E, 0x47]):
+        return 'png'
+    if header[:3] == b'GIF':
+        return 'gif'
+    if header[:4] == b'RIFF' and len(header) >= 12 and header[8:12] == b'WEBP':
+        return 'webp'
+    if header[:4] == b'wxgf':
+        return 'hevc'
+    return 'bin'
+
+
+# V2 格式常量
+_V2_MAGIC_FULL = b'\x07\x08V2\x08\x07'
+_V1_MAGIC_FULL = b'\x07\x08V1\x08\x07'
+_IMAGE_MAGICS = {
+    'jpg': [0xFF, 0xD8, 0xFF],
+    'png': [0x89, 0x50, 0x4E, 0x47],
+    'gif': [0x47, 0x49, 0x46, 0x38],
+    'webp': [0x52, 0x49, 0x46, 0x46],
+}
+
+
+def _decrypt_dat_to_bytes(dat_path):
+    """解密 .dat 文件，返回 (bytes, format) 或 (None, None)"""
+    with open(dat_path, 'rb') as f:
+        data = f.read()
+    if len(data) < 15:
+        return None, None
+    head6 = data[:6]
+
+    # V2 / V1 格式
+    if head6 in (_V2_MAGIC_FULL, _V1_MAGIC_FULL):
+        aes_key = None
+        if head6 == _V1_MAGIC_FULL:
+            aes_key = b'cfcd208495d565ef'
+        elif IMAGE_AES_KEY:
+            aes_key = IMAGE_AES_KEY.encode('ascii')[:16] if isinstance(IMAGE_AES_KEY, str) else IMAGE_AES_KEY[:16]
+        if not aes_key or len(aes_key) < 16:
+            return None, None
+        try:
+            from Crypto.Cipher import AES as _AES
+            from Crypto.Util import Padding
+            aes_size, xor_size = struct.unpack_from('<LL', data, 6)
+            aligned = aes_size - ~(~aes_size % 16)
+            offset = 15
+            if offset + aligned > len(data):
+                return None, None
+            cipher = _AES.new(aes_key[:16], _AES.MODE_ECB)
+            dec_aes = Padding.unpad(cipher.decrypt(data[offset:offset+aligned]), _AES.block_size)
+            offset += aligned
+            raw_end = len(data) - xor_size
+            raw_data = data[offset:raw_end] if offset < raw_end else b''
+            xor_data = data[raw_end:]
+            xor_key = IMAGE_XOR_KEY if isinstance(IMAGE_XOR_KEY, int) else 0x88
+            dec_xor = bytes(b ^ xor_key for b in xor_data)
+            result = dec_aes + raw_data + dec_xor
+            fmt = _detect_image_format(result[:16])
+            return result, fmt
+        except Exception:
+            return None, None
+
+    # 旧 XOR 格式
+    for fmt_name, magic in _IMAGE_MAGICS.items():
+        key = data[0] ^ magic[0]
+        match = all(i < len(data) and (data[i] ^ key) == magic[i] for i in range(len(magic)))
+        if match:
+            result = bytes(b ^ key for b in data)
+            fmt = _detect_image_format(result[:16])
+            return result, fmt
+
+    return None, None
+
+
+_resource_md5_map = _load_resource_md5_map() if _EXPORT_IMAGES else {}
+
+
+def decode_chat_images(chat_username, _messages_unused, out_dir):
+    """直接扫描 attach 目录下该联系人的全部图片并解密
+    按月份分目录输出到 out_dir/image/<YYYY-MM>/
+    跳过 _t 缩略图，优先 _h 高清版
+    返回 {file_md5: relative_path} 用于 HTML 嵌入
+    """
+    image_map = {}
+    username_hash = hashlib.md5(chat_username.encode()).hexdigest()
+
+    # 收集所有来源目录: [(base_path, sub_structure), ...]
+    # xwechat: attach/<hash>/<YYYY-MM>/Img/<md5>*.dat
+    # WeChat Files: MsgAttach/<hash>/Image/<YYYY-MM>/<md5>*.dat
+    source_dirs = []
+    if ATTACH_DIR:
+        p = os.path.join(ATTACH_DIR, username_hash)
+        if os.path.isdir(p):
+            source_dirs.append(("xwechat", p))
+    if MSGATTACH_DIR:
+        p = os.path.join(MSGATTACH_DIR, username_hash)
+        if os.path.isdir(p):
+            source_dirs.append(("wechat", p))
+
+    if not source_dirs:
+        return image_map
+
+    # 收集所有 dat 文件: {base_md5: (best_path, month)}
+    # 优先级: _h > 无后缀 > _W > 其他（跳过 _t）
+    file_candidates = {}  # base_md5 -> (priority, dat_path, month)
+
+    def _priority(fname):
+        """返回优先级数字，越小越好"""
+        base = fname.rsplit('.', 1)[0]
+        if base.endswith('_h'):
+            return 0  # 高清
+        if '_' not in base[-3:]:
+            return 1  # 无后缀原图
+        if base.endswith('_W'):
+            return 2
+        return 9  # 其他
+
+    for src_type, base_path in source_dirs:
+        # xwechat: <hash>/<YYYY-MM>/Img/  — 直接列 base_path 得到月份
+        # wechat:  <hash>/Image/<YYYY-MM>/ — 需要列 base_path/Image 得到月份
+        if src_type == "xwechat":
+            scan_base = base_path
+        else:
+            scan_base = os.path.join(base_path, "Image")
+        try:
+            months = sorted(os.listdir(scan_base))
+        except OSError:
+            continue
+        for month in months:
+            if src_type == "xwechat":
+                img_dir = os.path.join(base_path, month, "Img")
+            else:
+                img_dir = os.path.join(scan_base, month)
+            if not os.path.isdir(img_dir):
+                continue
+            try:
+                files = os.listdir(img_dir)
+            except OSError:
+                continue
+            for fname in files:
+                if not fname.endswith('.dat'):
+                    continue
+                # 跳过缩略图 _t.dat 和 _t_W.dat
+                base_no_ext = fname.rsplit('.', 1)[0]
+                if '_t' in base_no_ext.split('_'):
+                    continue
+                if base_no_ext.endswith('_t') or '_t_' in base_no_ext:
+                    continue
+                # 提取 base md5
+                base_md5 = base_no_ext.split('_')[0]
+                pri = _priority(fname)
+                existing = file_candidates.get(base_md5)
+                if not existing or pri < existing[0]:
+                    file_candidates[base_md5] = (pri, os.path.join(img_dir, fname), month)
+
+    if not file_candidates:
+        return image_map
+
+    decoded_count = 0
+    for base_md5, (pri, dat_path, month) in file_candidates.items():
+        month_dir = os.path.join(out_dir, "image", month)
+        # 检查是否已解密
+        existing = glob.glob(os.path.join(month_dir, f"{base_md5}.*"))
+        if existing:
+            rel = os.path.relpath(existing[0], out_dir).replace("\\", "/")
+            image_map[base_md5] = rel
+            continue
+        img_bytes, fmt = _decrypt_dat_to_bytes(dat_path)
+        if not img_bytes or fmt == 'bin':
+            continue
+        os.makedirs(month_dir, exist_ok=True)
+        out_path = os.path.join(month_dir, f"{base_md5}.{fmt}")
+        with open(out_path, 'wb') as f:
+            f.write(img_bytes)
+        image_map[base_md5] = f"image/{month}/{base_md5}.{fmt}"
+        decoded_count += 1
+
+    return image_map
 
 MSG_TYPES = {
     1: "文本",
@@ -127,6 +433,7 @@ body{{background:#ededed;font-family:"PingFang SC","Helvetica Neue",Arial,sans-s
 .bubble{{display:inline-block;padding:8px 12px;border-radius:6px;word-break:break-word;line-height:1.5;box-shadow:0 1px 2px rgba(0,0,0,.1);white-space:pre-wrap}}
 .received .bubble{{background:#fff;border-radius:0 6px 6px 6px}}
 .sent .bubble{{background:#95EC69;border-radius:6px 0 6px 6px}}
+.bubble img{{max-width:100%;border-radius:4px;display:block;margin:2px 0}}
 .type-tag{{font-size:11px;color:#aaa;margin-top:2px}}
 </style>
 </head>
@@ -142,7 +449,7 @@ body{{background:#ededed;font-family:"PingFang SC","Helvetica Neue",Arial,sans-s
 def _html_escape(s: str) -> str:
     return s.replace("&","&amp;").replace("<","&lt;").replace(">","&gt;").replace('"','&quot;')
 
-def _write_html(path: str, title: str, is_group: bool, messages: list):
+def _write_html(path: str, title: str, is_group: bool, messages: list, image_map: dict = None, out_dir: str = None):
     parts = []
     last_date = None
     for m in messages:
@@ -169,12 +476,33 @@ def _write_html(path: str, title: str, is_group: bool, messages: list):
         if m["type"] != 1:
             type_tag = f'<div class="type-tag">{m["type_name"]}</div>'
 
+        # 图片消息嵌入
+        bubble_content = _html_escape(m["display_content"])
+        if m["type"] == 3 and image_map and m["local_id"] in image_map:
+            rel_path = image_map[m["local_id"]]
+            if out_dir:
+                abs_img = os.path.join(out_dir, rel_path)
+                if os.path.exists(abs_img):
+                    ext = os.path.splitext(abs_img)[1].lstrip('.').lower()
+                    mime = {'jpg': 'image/jpeg', 'jpeg': 'image/jpeg', 'png': 'image/png',
+                            'gif': 'image/gif', 'webp': 'image/webp'}.get(ext, 'image/jpeg')
+                    try:
+                        with open(abs_img, 'rb') as imgf:
+                            b64 = base64.b64encode(imgf.read()).decode('ascii')
+                        bubble_content = f'<img src=\"data:{mime};base64,{b64}\" alt=\"图片\">'
+                    except Exception:
+                        bubble_content = f'<img src=\"{_html_escape(rel_path)}\" alt=\"图片\">'
+                else:
+                    bubble_content = f'<img src=\"{_html_escape(rel_path)}\" alt=\"图片\">'
+            else:
+                bubble_content = f'<img src=\"{_html_escape(rel_path)}\" alt=\"图片\">'
+
         parts.append(
             f'<div class="msg {side}">'
             f'<div class="avatar">{initial}</div>'
             f'<div class="msg-body">'
             f'{sender_label}'
-            f'<div class="bubble">{_html_escape(m["display_content"])}</div>'
+            f'<div class="bubble">{bubble_content}</div>'
             f'{type_tag}'
             f'<div class="type-tag">{m["time_str"]}</div>'
             f'</div></div>'
@@ -217,6 +545,10 @@ print(f"找到 {len(db_files)} 个消息数据库")
 total_chats = 0
 total_msgs = 0
 
+# ── 阶段1: 收集所有联系人的消息 ──────────────────────────────────────────────
+# chat_data[chat_username] -> { dname, is_group, db_messages: [(db_name, messages)] }
+chat_data: dict[str, dict] = {}
+
 for db_path in sorted(db_files):
     db_name = os.path.basename(db_path)
     conn = sqlite3.connect(db_path)
@@ -244,6 +576,8 @@ for db_path in sorted(db_files):
     for table_name in all_tables:
         h = table_name[4:]  # strip "Msg_"
         chat_username = hash_to_username.get(h, f"unknown_{h[:8]}")
+        if _CONTACT_FILTER and chat_username not in _CONTACT_FILTER:
+            continue
         dname = safe_dirname(display_name(chat_username))
         is_group = chat_username.endswith("@chatroom") or chat_username.endswith("@openim")
 
@@ -287,58 +621,93 @@ for db_path in sorted(db_files):
                 "content": content,
                 "display_content": display_content,
                 "is_system": is_system,
-                # 1-on-1: sender==chat_partner -> received(left), else sent(right)
                 "is_received": (sender_uname == chat_username) if not is_group else True,
             })
 
-        # ── 输出目录 ──────────────────────────────────────────────────────────
-        out_dir = os.path.join(OUTPUT_DIR, dname)
-        os.makedirs(out_dir, exist_ok=True)
+        if chat_username not in chat_data:
+            chat_data[chat_username] = {
+                "dname": dname, "is_group": is_group, "db_messages": []
+            }
+        chat_data[chat_username]["db_messages"].append((db_name, messages))
 
-        # ── .info 文件 ────────────────────────────────────────────────────────
-        info_path = os.path.join(out_dir, ".info")
-        if not os.path.exists(info_path):
-            info = contact_map.get(chat_username, {
-                "username": chat_username, "alias": "", "remark": "", "nick_name": ""
-            })
-            with open(info_path, "w", encoding="utf-8") as f:
-                f.write(f"username:  {info['username']}\n")
-                f.write(f"alias:     {info['alias']}\n")
-                f.write(f"nick_name: {info['nick_name']}\n")
-                f.write(f"remark:    {info['remark']}\n")
-                f.write(f"is_group:  {is_group}\n")
+    conn.close()
 
-        # ── CSV ───────────────────────────────────────────────────────────────
-        csv_path = os.path.join(out_dir, f"{db_name}.csv")
-        with open(csv_path, "w", newline="", encoding="utf-8-sig") as f:
-            w = csv.writer(f)
-            w.writerow(["时间", "发送者", "消息类型", "内容", "server_id"])
+# ── 阶段2: 每个联系人解密图片一次，再写出文件 ────────────────────────────────
+total_chats = 0
+total_msgs = 0
+
+for chat_username, cdata in chat_data.items():
+    dname = cdata["dname"]
+    is_group = cdata["is_group"]
+    out_dir = os.path.join(OUTPUT_DIR, dname)
+    os.makedirs(out_dir, exist_ok=True)
+
+    # ── .info 文件 ────────────────────────────────────────────────────────
+    info_path = os.path.join(out_dir, ".info")
+    if not os.path.exists(info_path):
+        info = contact_map.get(chat_username, {
+            "username": chat_username, "alias": "", "remark": "", "nick_name": ""
+        })
+        with open(info_path, "w", encoding="utf-8") as f:
+            f.write(f"username:  {info['username']}\n")
+            f.write(f"alias:     {info['alias']}\n")
+            f.write(f"nick_name: {info['nick_name']}\n")
+            f.write(f"remark:    {info['remark']}\n")
+            f.write(f"is_group:  {is_group}\n")
+
+    # ── 解密图片（每个联系人只执行一次）────────────────────────────────────
+    image_md5_map = {}
+    if _EXPORT_IMAGES:
+        image_md5_map = decode_chat_images(chat_username, None, out_dir)
+        if image_md5_map:
+            print(f"  图片解密: {len(image_md5_map)} 张 ({dname})")
+
+    # ── 按 DB 写出消息文件 ────────────────────────────────────────────────
+    for db_name, messages in cdata["db_messages"]:
+        # 建立 local_id -> rel_path 映射
+        image_map = {}
+        if image_md5_map:
             for m in messages:
-                w.writerow([
-                    m["time_str"], m["sender"], m["type_name"],
-                    m["display_content"], m["server_id"]
-                ])
+                if m["type"] != 3:
+                    continue
+                lid = m["local_id"]
+                file_md5 = _resource_md5_map.get((chat_username, lid))
+                if file_md5 and file_md5 in image_md5_map:
+                    image_map[lid] = image_md5_map[file_md5]
 
-        # ── JSON ──────────────────────────────────────────────────────────────
-        json_path = os.path.join(out_dir, f"{db_name}.json")
-        with open(json_path, "w", encoding="utf-8") as f:
-            json.dump({
-                "chat_username": chat_username,
-                "display_name": dname,
-                "is_group": is_group,
-                "message_count": len(messages),
-                "messages": messages,
-            }, f, ensure_ascii=False, indent=2)
+        # ── CSV ───────────────────────────────────────────────────────────
+        if not _EXPORT_FORMATS or "csv" in _EXPORT_FORMATS:
+            csv_path = os.path.join(out_dir, f"{db_name}.csv")
+            with open(csv_path, "w", newline="", encoding="utf-8-sig") as f:
+                w = csv.writer(f)
+                w.writerow(["时间", "发送者", "消息类型", "内容", "图片路径", "server_id"])
+                for m in messages:
+                    img_path = image_map.get(m["local_id"], "") if m["type"] == 3 else ""
+                    w.writerow([
+                        m["time_str"], m["sender"], m["type_name"],
+                        m["display_content"], img_path, m["server_id"]
+                    ])
 
-        # ── HTML ──────────────────────────────────────────────────────────────
-        html_path = os.path.join(out_dir, f"{db_name}.html")
-        _write_html(html_path, dname, is_group, messages)
+        # ── JSON ──────────────────────────────────────────────────────────
+        if not _EXPORT_FORMATS or "json" in _EXPORT_FORMATS:
+            json_path = os.path.join(out_dir, f"{db_name}.json")
+            with open(json_path, "w", encoding="utf-8") as f:
+                json.dump({
+                    "chat_username": chat_username,
+                    "display_name": dname,
+                    "is_group": is_group,
+                    "message_count": len(messages),
+                    "messages": messages,
+                }, f, ensure_ascii=False, indent=2)
+
+        # ── HTML ──────────────────────────────────────────────────────────
+        if not _EXPORT_FORMATS or "html" in _EXPORT_FORMATS:
+            html_path = os.path.join(out_dir, f"{db_name}.html")
+            _write_html(html_path, dname, is_group, messages, image_map=image_map, out_dir=out_dir)
 
         total_chats += 1
         total_msgs += len(messages)
         print(f"  [{db_name}] {dname}: {len(messages)} 条消息")
 
-    conn.close()
-
 print(f"\n完成: {total_chats} 个会话, 共 {total_msgs} 条消息")
 print(f"输出目录: {os.path.abspath(OUTPUT_DIR)}")