improvement(import): 支持 wxdump 目录导入并增加导入保护

- 兼容 wxdump 的 output 目录、database/ 和 media/ 结构

- 缺少 account.json 时自动推断账号信息并补充导入预览

- 导入前展示目标账号状态，并拦截源目录与目标目录重叠的情况

- 支持取消导入、已有账号自动备份，以及失败/取消后的回滚恢复

- 补充资源查找兼容逻辑，适配 wxdump 导入后的媒体文件布局

frontend/pages/import.vue

@@ -2,7 +2,7 @@
   <div class="import-page min-h-screen relative overflow-hidden">
     <div class="absolute inset-0 bg-grid-pattern opacity-5 pointer-events-none"></div>
 
-    <div class="relative z-10 mx-auto flex min-h-screen w-full max-w-3xl items-center justify-center px-4 py-6 sm:px-6 sm:py-8">
+    <div class="relative z-10 mx-auto flex min-h-screen w-full max-w-4xl items-center justify-center px-4 py-6 sm:px-6 sm:py-8">
       <div class="w-full rounded-[28px] border border-[#EDEDED] bg-white/92 backdrop-blur-sm">
         <div class="px-5 py-5 sm:px-7 sm:py-7">
           <div class="mb-5 flex items-start justify-between gap-3">
@@ -13,9 +13,9 @@
                 </svg>
               </div>
               <div class="min-w-0">
-                <p class="text-[11px] uppercase tracking-[0.12em] text-[#7F7F7F]">Import backup</p>
+                <p class="text-[11px] uppercase tracking-[0.12em] text-[#7F7F7F]">导入备份</p>
                 <h1 class="mt-1 text-[24px] font-semibold leading-none text-[#000000e6]">数据导入</h1>
-                <p class="mt-2 text-sm text-[#7F7F7F]">导入已解密的微信备份目录，确认账号后即可写入当前工具。</p>
+                <p class="mt-2 text-sm text-[#7F7F7F]">导入已解密的微信备份目录，支持本项目导出和 wxdump 的 output/wxid_xxx 结构。</p>
               </div>
             </div>
 
@@ -30,27 +30,26 @@
             </NuxtLink>
           </div>
 
-          <div class="mb-5 rounded-[22px] border border-[#E8EFE8] bg-[#F8FBF8] px-4 py-4">
-            <div class="flex items-center gap-2 text-[13px] font-semibold text-[#000000d9]">
-              <svg class="h-4 w-4 text-[#07C160]" fill="none" stroke="currentColor" viewBox="0 0 24 24">
-                <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M13 16h-1v-4h-1m1-4h.01M21 12a9 9 0 11-18 0 9 9 0 0118 0z" />
-              </svg>
-              <span>目录要求</span>
-            </div>
-            <div class="mt-3 grid gap-2 sm:grid-cols-3">
-              <div class="rounded-2xl border border-white bg-white/80 px-3 py-3">
-                <p class="text-[11px] uppercase tracking-[0.08em] text-[#7F7F7F]">Target</p>
-                <p class="mt-1 text-sm leading-6 text-[#000000d9]">请选择 `output / wxid_xxxxx` 这一层目录。</p>
+          <div class="mb-5 rounded-[22px] border border-[#E8EFE8] bg-[#F8FBF8] px-4 py-4 sm:px-5">
+            <div class="flex flex-col gap-3 sm:flex-row sm:items-start sm:justify-between">
+              <div class="flex min-w-0 items-start gap-3">
+                <div class="mt-0.5 flex h-8 w-8 shrink-0 items-center justify-center rounded-xl bg-white text-[#07C160] ring-1 ring-[#E7F1E8]">
+                  <svg class="h-4 w-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+                    <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M13 16h-1v-4h-1m1-4h.01M21 12a9 9 0 11-18 0 9 9 0 0118 0z" />
+                  </svg>
+                </div>
+                <div class="min-w-0">
+                  <div class="text-[13px] font-semibold text-[#000000d9]">目录要求</div>
+                  <p class="mt-1 text-sm leading-6 text-[#6F6F6F]">支持本项目导出和 wxdump 导出。优先选择账号目录；若 output 下只有一个账号，也可直接选 output。</p>
+                </div>
               </div>
-              <div class="rounded-2xl border border-white bg-white/80 px-3 py-3">
-                <p class="text-[11px] uppercase tracking-[0.08em] text-[#7F7F7F]">Database</p>
-                <p class="mt-1 text-sm leading-6 text-[#000000d9]">目录内需要包含 `databases/`，用于存放 `.db` 文件。</p>
-              </div>
-              <div class="rounded-2xl border border-white bg-white/80 px-3 py-3">
-                <p class="text-[11px] uppercase tracking-[0.08em] text-[#7F7F7F]">Account</p>
-                <p class="mt-1 text-sm leading-6 text-[#000000d9]">`account.json` 会作为账号识别与信息校验依据。</p>
+              <div class="flex shrink-0 flex-wrap gap-2 sm:justify-end">
+                <span class="inline-flex items-center rounded-full border border-[#DDEBE0] bg-white px-3 py-1 text-xs font-medium text-[#4A4A4A]">databases/</span>
+                <span class="inline-flex items-center rounded-full border border-[#DDEBE0] bg-white px-3 py-1 text-xs font-medium text-[#4A4A4A]">database/</span>
+                <span class="inline-flex items-center rounded-full border border-[#DDEBE0] bg-white px-3 py-1 text-xs font-medium text-[#4A4A4A]">media/</span>
               </div>
             </div>
+
           </div>
 
           <div v-if="!importPreview && !importError && !importing" class="animate-fade-in">
@@ -64,7 +63,7 @@
                 </svg>
               </div>
               <h3 class="mt-4 text-lg font-semibold text-[#000000e6]">选择解密备份目录</h3>
-              <p class="mt-2 text-sm text-[#7F7F7F]">建议直接选择 `wxid_xxxxx` 层级，减少后续校验失败。</p>
+              <p class="mt-2 text-sm text-[#7F7F7F]">建议选择 `wxid_xxxxx` 层级；wxdump 的 `output` 根目录在单账号时也支持。</p>
               <div class="mt-5 inline-flex items-center rounded-full bg-[#07C160] px-4 py-2 text-sm font-medium text-white transition-colors duration-200 group-hover:bg-[#06AD56]">
                 点击开始选择
               </div>
@@ -81,7 +80,7 @@
 
               <div class="mt-5 text-center">
                 <p class="text-xl font-semibold text-[#000000e6]">{{ importMessage }}</p>
-                <p class="mt-2 text-sm text-[#7F7F7F]">请保持程序运行，导入完成后会自动进入聊天页面。</p>
+                <p class="mt-2 text-sm text-[#7F7F7F]">请保持程序运行，导入完成后可手动进入聊天页面。</p>
               </div>
 
               <div class="mt-6 overflow-hidden rounded-full bg-[#EDF3EE]">
@@ -95,19 +94,62 @@
                 <span>已连接导入任务</span>
                 <span>{{ importProgress }}%</span>
               </div>
+
+              <button
+                class="mt-5 inline-flex w-full items-center justify-center rounded-2xl border border-[#F0D7D7] bg-white px-4 py-3 text-sm font-medium text-[#D64A4A] transition-colors hover:bg-[#FFF7F7]"
+                @click="cancelImport"
+              >
+                取消导入
+              </button>
             </div>
           </div>
 
-          <div v-if="importPreview && !importing" class="animate-fade-in space-y-4">
+          <div v-if="importComplete && !importing" class="animate-fade-in space-y-4">
+            <div class="rounded-[24px] border border-[#DCEFE2] bg-[#F7FCF8] px-5 py-7 text-center sm:px-6">
+              <div class="mx-auto flex h-14 w-14 items-center justify-center rounded-2xl bg-[#07C160]/10 text-[#07C160]">
+                <svg class="h-7 w-7" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+                  <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M5 13l4 4L19 7" />
+                </svg>
+              </div>
+              <h2 class="mt-4 text-xl font-semibold text-[#000000e6]">导入完成</h2>
+              <p class="mt-2 text-sm leading-6 text-[#6F6F6F]">{{ importComplete.message || '账号数据已成功导入。' }}</p>
+              <div class="mt-4 rounded-2xl border border-[#E2EFE5] bg-white px-4 py-3 text-left text-sm text-[#4A4A4A]">
+                <div class="flex items-center justify-between gap-3">
+                  <span class="text-[#7F7F7F]">账号</span>
+                  <span class="min-w-0 truncate font-mono text-xs">{{ importComplete.account }}</span>
+                </div>
+                <div v-if="importComplete.backup_dir" class="mt-2 flex items-start justify-between gap-3">
+                  <span class="shrink-0 text-[#7F7F7F]">旧数据备份</span>
+                  <span class="min-w-0 break-all text-right text-xs">{{ importComplete.backup_dir }}</span>
+                </div>
+              </div>
+              <div class="mt-5 grid gap-3 sm:grid-cols-2">
+                <button
+                  class="inline-flex items-center justify-center rounded-2xl border border-[#E2E2E2] bg-white px-4 py-3 text-sm font-medium text-[#4A4A4A] transition-colors hover:bg-[#F8F8F8]"
+                  @click="retryPickDirectory"
+                >
+                  继续导入其他目录
+                </button>
+                <button
+                  class="inline-flex items-center justify-center rounded-2xl bg-[#07C160] px-4 py-3 text-sm font-medium text-white transition-colors hover:bg-[#06AD56]"
+                  @click="navigateTo('/chat')"
+                >
+                  进入聊天页面
+                </button>
+              </div>
+            </div>
+          </div>
+
+          <div v-if="importPreview && !importing && !importComplete" class="animate-fade-in space-y-4">
             <div class="rounded-[24px] border border-[#EDEDED] bg-[#FCFDFC] px-5 py-5 sm:px-6">
               <div class="flex flex-col gap-4 sm:flex-row sm:items-center sm:justify-between">
                 <div class="flex min-w-0 items-center gap-4">
                   <div class="h-16 w-16 shrink-0 overflow-hidden rounded-2xl border border-[#EDEDED] bg-white">
-                    <img :src="importPreview.avatar_url || '/Contact.png'" class="h-full w-full object-cover" alt="Avatar" />
+                    <img :src="importPreview.avatar_url || '/Contact.png'" class="h-full w-full object-cover" alt="头像" />
                   </div>
 
                   <div class="min-w-0">
-                    <p class="text-[11px] uppercase tracking-[0.12em] text-[#7F7F7F]">Detected account</p>
+                    <p class="text-[11px] uppercase tracking-[0.12em] text-[#7F7F7F]">检测到的账号</p>
                     <div class="mt-1 truncate text-xl font-semibold text-[#000000e6]">{{ importPreview.nick || '未命名账号' }}</div>
                     <div class="mt-2 inline-flex max-w-full items-center rounded-full border border-[#EDEDED] bg-white px-3 py-1 text-xs font-mono text-[#7F7F7F]">
                       <span class="truncate">{{ importPreview.username }}</span>
@@ -121,7 +163,7 @@
               </div>
 
               <div v-if="selectedImportPath" class="mt-4 rounded-[18px] border border-[#EDEDED] bg-white px-3 py-3">
-                <p class="text-[11px] uppercase tracking-[0.12em] text-[#7F7F7F]">Import path</p>
+                <p class="text-[11px] uppercase tracking-[0.12em] text-[#7F7F7F]">导入路径</p>
                 <p class="mt-1 break-all text-sm text-[#000000d9]">{{ selectedImportPath }}</p>
               </div>
 
@@ -145,7 +187,7 @@
                 重新选择目录
               </button>
               <button
-                :disabled="importing"
+                :disabled="importing || importPreview?.source_overlaps_target"
                 class="inline-flex items-center justify-center rounded-2xl bg-[#07C160] px-4 py-3 text-sm font-medium text-white transition-colors hover:bg-[#06AD56] disabled:cursor-not-allowed disabled:bg-[#8FD9AE]"
                 @click="confirmImport"
               >
@@ -169,7 +211,7 @@
               </div>
 
               <div v-if="selectedImportPath" class="mt-4 rounded-[18px] border border-[#F1E3E3] bg-white/80 px-3 py-3">
-                <p class="text-[11px] uppercase tracking-[0.12em] text-[#B26B6B]">Current path</p>
+                <p class="text-[11px] uppercase tracking-[0.12em] text-[#B26B6B]">当前路径</p>
                 <p class="mt-1 break-all text-sm text-[#7A4B4B]">{{ selectedImportPath }}</p>
               </div>
             </div>
@@ -197,7 +239,9 @@ const importProgress = ref(0)
 const importMessage = ref('正在准备...')
 const importPreview = ref(null)
 const importError = ref('')
+const importComplete = ref(null)
 const selectedImportPath = ref('')
+const importJobId = ref('')
 
 let eventSource = null
 
@@ -220,23 +264,24 @@ const isDesktopShell = () => {
 const resetImport = () => {
   closeEventSource()
   importPreview.value = null
+  importComplete.value = null
   importError.value = ''
   selectedImportPath.value = ''
   importing.value = false
   importProgress.value = 0
   importMessage.value = '正在准备...'
+  importJobId.value = ''
 }
 
 const { importDecryptedPreview, pickSystemDirectory } = useApi()
 const apiBase = useApiBase()
-
 const handlePickDirectory = async () => {
   let path = ''
 
   if (isDesktopShell()) {
     try {
       const res = await window.wechatDesktop.chooseDirectory({
-        title: '请选择解密输出目录 (如: output/wxid_xxxxx)'
+        title: '请选择解密输出目录 (如: output/wxid_xxxxx 或单账号 output)'
       })
       if (!res || res.canceled || !res.filePaths?.length) return
       path = res.filePaths[0]
@@ -246,7 +291,7 @@ const handlePickDirectory = async () => {
     }
   } else {
     try {
-      const res = await pickSystemDirectory({ title: '请选择解密输出目录 (需选到 wxid_xxx 层级)' })
+      const res = await pickSystemDirectory({ title: '请选择解密输出目录 (建议选到 wxid_xxx 层级)' })
       if (!res || !res.path) return
       path = res.path
     } catch (e) {
@@ -260,7 +305,7 @@ const handlePickDirectory = async () => {
     const isOk = window.confirm(`你选择的目录为：
 ${path}
 
-该目录似乎不符合 "wxid_xxxxx" 的格式。确定要继续吗？`)
+该目录似乎不是 "wxid_xxxxx" 账号目录。如果这是 wxdump 的单账号 output 根目录，可以继续。确定要继续吗？`)
     if (!isOk) return
   }
 
@@ -271,7 +316,7 @@ ${path}
   try {
     importPreview.value = await importDecryptedPreview({ import_path: path })
   } catch (e) {
-    importError.value = e.message || '目录格式不正确，请确保包含 databases 目录和 account.json'
+    importError.value = e.message || '目录格式不正确，请确保包含 databases/database 目录；wxdump 格式可不含 account.json'
   }
 }
 
@@ -280,16 +325,65 @@ const retryPickDirectory = async () => {
   await handlePickDirectory()
 }
 
+const makeImportJobId = () => {
+  const randomPart = typeof crypto !== 'undefined' && crypto.randomUUID
+    ? crypto.randomUUID()
+    : `${Date.now()}-${Math.random().toString(16).slice(2)}`
+  return `import-${randomPart}`
+}
+
+const cancelImport = async () => {
+  const jobId = importJobId.value
+  closeEventSource()
+  importing.value = false
+  importProgress.value = 0
+  importMessage.value = '正在准备...'
+  importComplete.value = null
+  importError.value = ''
+
+  if (!jobId) return
+  try {
+    const url = new URL(`${apiBase.replace(/\/$/, '')}/import_decrypted/cancel`, window.location.origin)
+    url.searchParams.set('job_id', jobId)
+    await fetch(url.toString(), { method: 'POST' })
+  } catch (e) {
+    console.error('取消导入失败:', e)
+  } finally {
+    importJobId.value = ''
+  }
+}
+
+
 const confirmImport = async () => {
   if (!selectedImportPath.value) return
 
+  if (importPreview.value?.source_overlaps_target) {
+    importError.value = '导入源目录与目标数据目录相同或相互包含，请重新选择外部备份目录。'
+    return
+  }
+
+  if (importPreview.value?.target_exists) {
+    const ok = window.confirm(`当前账号已存在：${importPreview.value.username}
+
+继续导入会先自动备份旧目录，然后导入新数据。
+旧数据库数量：${importPreview.value.existing_db_count || 0}
+新数据库数量：${importPreview.value.incoming_db_count || 0}
+
+确定继续吗？`)
+    if (!ok) return
+  }
+
   importing.value = true
+
+  importComplete.value = null
   importError.value = ''
   importProgress.value = 0
   importMessage.value = '启动导入程序...'
+  importJobId.value = makeImportJobId()
 
   const url = new URL(`${apiBase.replace(/\/$/, '')}/import_decrypted`, window.location.origin)
   url.searchParams.set('import_path', selectedImportPath.value)
+  url.searchParams.set('job_id', importJobId.value)
 
   closeEventSource()
   eventSource = new EventSource(url.toString())
@@ -304,15 +398,17 @@ const confirmImport = async () => {
       } else if (data.type === 'complete') {
         importProgress.value = 100
         importMessage.value = '导入完成！'
-        closeEventSource()
-
-        setTimeout(async () => {
-          await navigateTo('/chat')
-        }, 1000)
-      } else if (data.type === 'error') {
-        importError.value = data.message || '导入失败'
+        importComplete.value = data
+        importError.value = ''
         importing.value = false
         closeEventSource()
+        importJobId.value = ''
+      } else if (data.type === 'error') {
+        importError.value = data.message || '导入失败'
+        importComplete.value = null
+        importing.value = false
+        closeEventSource()
+        importJobId.value = ''
       }
     } catch (e) {
       console.error('解析 SSE 数据失败:', e)
@@ -321,9 +417,15 @@ const confirmImport = async () => {
 
   eventSource.onerror = (e) => {
     console.error('EventSource 错误:', e)
+    if (!importing.value) {
+      closeEventSource()
+      return
+    }
+    importComplete.value = null
     importError.value = '与服务器连接断开或发生错误'
     importing.value = false
     closeEventSource()
+    importJobId.value = ''
   }
 }
 </script>

src/wechat_decrypt_tool/media_helpers.py

@@ -3051,14 +3051,26 @@ def _try_find_decrypted_resource(account_dir: Path, md5: str) -> Optional[Path]:
     if not resource_dir.exists():
         return None
     sub_dir = md5[:2] if len(md5) >= 2 else "00"
+
+    # Prefer the standard layout: resource/{md5-prefix}/{md5}.{ext}
     target_dir = resource_dir / sub_dir
-    if not target_dir.exists():
-        return None
-    # 查找匹配MD5的文件（可能有不同扩展名）
-    for ext in ["jpg", "png", "gif", "webp", "mp4", "dat"]:
-        p = target_dir / f"{md5}.{ext}"
-        if p.exists():
-            return p
+    search_dirs = [target_dir]
+
+    # Support wxdump flat media layout after it is imported as resource.
+    # Typical files: resource/{md5}.jpg, resource/{md5}_t.jpg, or resource/{md5}.wxgf.
+    if resource_dir not in search_dirs:
+        search_dirs.append(resource_dir)
+
+    exts = ["jpg", "png", "gif", "webp", "mp4", "dat", "wxgf", "wxgf.jpg"]
+    suffixes = ["", "_t", "_b", "_h"]
+    for directory in search_dirs:
+        if not directory.exists():
+            continue
+        for suffix in suffixes:
+            for ext in exts:
+                candidate = directory / f"{md5}{suffix}.{ext}"
+                if candidate.exists():
+                    return candidate
     return None
 
 

src/wechat_decrypt_tool/routers/import_decrypted.py

@@ -3,7 +3,9 @@ from __future__ import annotations
 import os
 import shutil
 import json
+import sqlite3
 import asyncio
+from datetime import datetime
 from pathlib import Path
 from typing import Optional
 from fastapi import APIRouter, HTTPException, Query
@@ -20,6 +22,12 @@ logger = get_logger(__name__)
 
 router = APIRouter(route_class=PathFixRoute)
 
+_IMPORT_CANCEL_EVENTS: dict[str, asyncio.Event] = {}
+
+
+class ImportCancelled(Exception):
+    pass
+
 class ImportRequest(BaseModel):
     import_path: str = Field(..., description="已解密的数据库和资源所在目录的绝对路径")
 
@@ -33,46 +41,180 @@ def _is_valid_sqlite(path: Path) -> bool:
     except Exception:
         return False
 
-def _validate_import_structure(import_path: Path) -> dict:
-    """
-    验证导入目录结构：
-    - databases/ (必须包含 contact.db, session.db)
-    - resource/ (可选)
-    - account.json (必须包含 username, nick)
-    """
-    db_dir = import_path / "databases"
-    account_json_path = import_path / "account.json"
-    
-    if not db_dir.exists() or not db_dir.is_dir():
-        raise HTTPException(status_code=400, detail="未找到 databases 目录")
-    
-    if not account_json_path.exists():
-        raise HTTPException(status_code=400, detail="未找到 account.json 文件")
-    
-    # 验证关键数据库
-    required_dbs = ["contact.db", "session.db"]
-    for db_name in required_dbs:
-        if not _is_valid_sqlite(db_dir / db_name):
-            raise HTTPException(status_code=400, detail=f"databases 目录中未找到有效的 {db_name}")
-            
-    # 解析 account.json
+def _clean_profile_text(value: object) -> str:
+    text = str(value or "").replace("\u3164", "").strip()
+    return text
+
+
+def _pick_import_account_dir(import_path: Path) -> Path:
+    """Resolve the actual account directory; supports selecting output root or wxid_xxx."""
+    if (import_path / "databases").is_dir() or (import_path / "database").is_dir():
+        return import_path
+    account_dirs: list[Path] = []
     try:
-        account_info = json.loads(account_json_path.read_text(encoding="utf-8"))
+        for child in import_path.iterdir():
+            if child.is_dir() and ((child / "databases").is_dir() or (child / "database").is_dir()):
+                account_dirs.append(child)
+    except Exception:
+        account_dirs = []
+    if len(account_dirs) == 1:
+        return account_dirs[0]
+    if len(account_dirs) > 1:
+        names = ", ".join(p.name for p in account_dirs[:5])
+        raise HTTPException(status_code=400, detail=f"Multiple account directories found. Please select one account directory: {names}")
+    return import_path
+
+
+def _pick_database_dir(account_dir: Path) -> Path:
+    """Support both this app's databases/ and wxdump's database/ directory names."""
+    for name in ("databases", "database"):
+        db_dir = account_dir / name
+        if db_dir.exists() and db_dir.is_dir():
+            return db_dir
+    raise HTTPException(status_code=400, detail="Missing databases or database directory")
+
+
+def _pick_resource_dir(account_dir: Path) -> Optional[Path]:
+    """Support both this app's resource/ and wxdump's media/ directory names."""
+    for name in ("resource", "media"):
+        resource_dir = account_dir / name
+        if resource_dir.exists() and resource_dir.is_dir():
+            return resource_dir
+    return None
+
+
+def _read_contact_profile(db_dir: Path, username: str) -> dict:
+    """Best-effort account profile inference from contact.db."""
+    contact_db = db_dir / "contact.db"
+    if not _is_valid_sqlite(contact_db):
+        return {}
+    try:
+        conn = sqlite3.connect(str(contact_db))
+        conn.row_factory = sqlite3.Row
+        try:
+            row = conn.execute("""
+                SELECT username, remark, nick_name, alias, big_head_url, small_head_url
+                FROM contact
+                WHERE username = ?
+                LIMIT 1
+                """, (username,)).fetchone()
+        finally:
+            conn.close()
+        if not row:
+            return {}
+        nick = _clean_profile_text(row["nick_name"]) or _clean_profile_text(row["remark"]) or _clean_profile_text(row["alias"]) or username
+        return {"username": _clean_profile_text(row["username"]) or username, "nick": nick, "avatar_url": str(row["big_head_url"] or row["small_head_url"] or "").strip(), "alias": _clean_profile_text(row["alias"])}
     except Exception as e:
-        raise HTTPException(status_code=400, detail=f"解析 account.json 失败: {e}")
-        
-    username = account_info.get("username")
-    nick = account_info.get("nick")
-    
-    if not username or not nick:
-        raise HTTPException(status_code=400, detail="account.json 中缺少 username 或 nick")
-        
-    return {
-        "username": username,
-        "nick": nick,
-        "avatar_url": account_info.get("avatar_url", ""),
-        "has_resource": (import_path / "resource").exists()
-    }
+        logger.warning(f"Failed to read account profile from contact.db: {contact_db}, {e}")
+        return {}
+
+
+def _load_or_infer_account_info(account_dir: Path, db_dir: Path) -> tuple[dict, Optional[Path], bool]:
+    """Read account.json; if missing in wxdump output, infer from folder name and contact.db."""
+    account_json_path = account_dir / "account.json"
+    if account_json_path.exists():
+        try:
+            account_info = json.loads(account_json_path.read_text(encoding="utf-8"))
+        except Exception as e:
+            raise HTTPException(status_code=400, detail=f"Failed to parse account.json: {e}")
+        username = _clean_profile_text(account_info.get("username"))
+        nick = _clean_profile_text(account_info.get("nick") or account_info.get("nickname"))
+        if not username or not nick:
+            raise HTTPException(status_code=400, detail="account.json is missing username or nick")
+        account_info["username"] = username
+        account_info["nick"] = nick
+        account_info.setdefault("avatar_url", "")
+        return account_info, account_json_path, False
+    inferred_username = _clean_profile_text(account_dir.name)
+    if not inferred_username:
+        raise HTTPException(status_code=400, detail="Missing account.json and cannot infer account from directory name")
+    profile = _read_contact_profile(db_dir, inferred_username)
+    username = _clean_profile_text(profile.get("username")) or inferred_username
+    nick = _clean_profile_text(profile.get("nick")) or _clean_profile_text(profile.get("alias")) or username
+    return {"username": username, "nick": nick, "avatar_url": str(profile.get("avatar_url") or ""), "alias": str(profile.get("alias") or "")}, None, True
+
+
+def _validate_import_structure(import_path: Path) -> dict:
+    account_dir = _pick_import_account_dir(import_path)
+    db_dir = _pick_database_dir(account_dir)
+    resource_dir = _pick_resource_dir(account_dir)
+    for db_name in ["contact.db", "session.db"]:
+        if not _is_valid_sqlite(db_dir / db_name):
+            raise HTTPException(status_code=400, detail=f"Missing valid {db_name} in {db_dir.name}")
+    account_info, account_json_path, inferred_account = _load_or_infer_account_info(account_dir, db_dir)
+    return {"username": account_info["username"], "nick": account_info["nick"], "avatar_url": account_info.get("avatar_url", ""), "alias": account_info.get("alias", ""), "has_resource": resource_dir is not None, "source_format": "wxdump" if db_dir.name == "database" or inferred_account else "wechat_data_analysis", "inferred_account": inferred_account, "account_dir": str(account_dir), "db_dir": str(db_dir), "resource_dir": str(resource_dir) if resource_dir else "", "account_json_path": str(account_json_path) if account_json_path else ""}
+
+
+def _count_db_files(db_dir: Path) -> int:
+    try:
+        return sum(1 for f in db_dir.iterdir() if f.is_file() and f.suffix.lower() == ".db")
+    except Exception:
+        return 0
+
+
+def _is_dir_nonempty(path: Path) -> bool:
+    try:
+        return path.exists() and path.is_dir() and any(path.iterdir())
+    except Exception:
+        return False
+
+
+def _paths_overlap(a: Path, b: Path) -> bool:
+    try:
+        ar = a.resolve()
+        br = b.resolve()
+    except Exception:
+        ar = a.absolute()
+        br = b.absolute()
+    return ar == br or ar in br.parents or br in ar.parents
+
+
+def _build_target_state(info: dict) -> dict:
+    output_base = get_output_databases_dir()
+    account_name = str(info.get("username") or "").strip()
+    target_dir = output_base / account_name if account_name else output_base
+    resource_dir = target_dir / "resource"
+    db_files: list[str] = []
+    try:
+        if target_dir.exists() and target_dir.is_dir():
+            db_files = sorted(f.name for f in target_dir.iterdir() if f.is_file() and f.suffix.lower() == ".db")
+    except Exception:
+        db_files = []
+    paths = [Path(str(info.get("account_dir") or "")), Path(str(info.get("db_dir") or ""))]
+    if info.get("resource_dir"):
+        paths.append(Path(str(info.get("resource_dir"))))
+    return {"target_dir": str(target_dir), "target_exists": target_dir.exists(), "target_nonempty": _is_dir_nonempty(target_dir), "existing_db_count": len(db_files), "existing_db_files": db_files[:50], "incoming_db_count": _count_db_files(Path(str(info.get("db_dir") or ""))), "target_has_resource": resource_dir.exists(), "will_replace_resource": bool(resource_dir.exists() and info.get("resource_dir")), "source_overlaps_target": any(_paths_overlap(x, target_dir) for x in paths if str(x))}
+
+
+def _next_backup_dir(account_output_dir: Path) -> Path:
+    stamp = datetime.now().strftime("%Y%m%d-%H%M%S")
+    base = account_output_dir.with_name(f"{account_output_dir.name}.backup-{stamp}")
+    candidate = base
+    i = 1
+    while candidate.exists():
+        candidate = account_output_dir.with_name(f"{base.name}-{i}")
+        i += 1
+    return candidate
+
+
+def _backup_existing_account_dir(account_output_dir: Path) -> Optional[Path]:
+    if not account_output_dir.exists():
+        return None
+    backup_dir = _next_backup_dir(account_output_dir)
+    shutil.move(str(account_output_dir), str(backup_dir))
+    return backup_dir
+
+
+def _rollback_account_backup(account_output_dir: Path, backup_dir: Optional[Path]) -> None:
+    if not backup_dir or not backup_dir.exists():
+        return
+    if account_output_dir.exists():
+        if account_output_dir.is_symlink() or account_output_dir.is_file():
+            account_output_dir.unlink()
+        else:
+            shutil.rmtree(account_output_dir)
+    shutil.move(str(backup_dir), str(account_output_dir))
+
 
 @router.post("/api/import_decrypted/preview", summary="预览待导入的账号信息")
 async def preview_import(request: ImportRequest):
@@ -80,18 +222,42 @@ async def preview_import(request: ImportRequest):
     if not import_path.exists() or not import_path.is_dir():
         raise HTTPException(status_code=400, detail="导入路径不存在或不是目录")
         
-    return _validate_import_structure(import_path)
+    info = _validate_import_structure(import_path)
+    info.update(_build_target_state(info))
+    return info
+
+@router.post("/api/import_decrypted/cancel", summary="取消正在执行的导入任务")
+async def cancel_import_decrypted(job_id: str = Query(..., description="导入任务 ID")):
+    cancel_event = _IMPORT_CANCEL_EVENTS.get(str(job_id or ""))
+    if cancel_event:
+        cancel_event.set()
+        return {"status": "cancel_requested"}
+    return {"status": "not_found"}
 
 @router.get("/api/import_decrypted", summary="执行导入已解密的数据库和资源目录 (SSE)")
 async def import_decrypted_directory(
-    import_path: str = Query(..., description="已解密的数据库和资源所在目录的绝对路径")
+    import_path: str = Query(..., description="已解密的数据库和资源所在目录的绝对路径"),
+    job_id: str = Query("", description="导入任务 ID，用于取消导入")
 ):
     import_path_obj = Path(import_path.strip())
+    account_output_dir: Optional[Path] = None
+    backup_dir: Optional[Path] = None
+    backup_restored = False
+    job_key = str(job_id or "").strip()
+    cancel_event: Optional[asyncio.Event] = None
+    if job_key:
+        cancel_event = _IMPORT_CANCEL_EVENTS.setdefault(job_key, asyncio.Event())
+        cancel_event.clear()
     
     def _sse(data: dict):
         return f"data: {json.dumps(data, ensure_ascii=False)}\n\n"
 
+    def _check_cancel():
+        if cancel_event is not None and cancel_event.is_set():
+            raise ImportCancelled("用户已取消导入")
+
     async def generate_progress():
+        nonlocal account_output_dir, backup_dir, backup_restored
         try:
             if not import_path_obj.exists() or not import_path_obj.is_dir():
                 yield _sse({"type": "error", "message": "导入路径不存在或不是目录"})
@@ -108,22 +274,34 @@ async def import_decrypted_directory(
                 yield _sse({"type": "error", "message": f"验证失败: {e}"})
                 return
             
+            _check_cancel()
+            info.update(_build_target_state(info))
+            if info.get("source_overlaps_target"):
+                yield _sse({"type": "error", "message": "导入源目录与目标数据目录相同或相互包含，请选择外部备份目录。"})
+                return
+
             account_name = info["username"]
-            yield _sse({"type": "progress", "percent": 10, "message": f"验证成功: {account_name}"})
+            yield _sse({"type": "progress", "percent": 10, "message": f"验证成功：{account_name}"})
             
-            # 2. 准备输出目录
+            # 2. 准备目标目录；如果已有账号数据，先整体备份再替换。
             output_base = get_output_databases_dir()
             account_output_dir = output_base / account_name
+            if account_output_dir.exists():
+                yield _sse({"type": "progress", "percent": 12, "message": "检测到已有账号数据，正在创建备份..."})
+                backup_dir = await asyncio.to_thread(_backup_existing_account_dir, account_output_dir)
+                if backup_dir:
+                    yield _sse({"type": "progress", "percent": 14, "message": f"已创建备份：{backup_dir.name}"})
             await asyncio.to_thread(account_output_dir.mkdir, parents=True, exist_ok=True)
 
             yield _sse({"type": "progress", "percent": 15, "message": "正在准备目标目录..."})
 
             # 3. 导入 databases 目录下的 .db 文件
-            db_src_dir = import_path_obj / "databases"
+            db_src_dir = Path(info["db_dir"])
             db_files = [f for f in db_src_dir.iterdir() if f.is_file() and f.suffix == ".db"]
             imported_files = []
             
             for i, item in enumerate(db_files):
+                _check_cancel()
                 target = account_output_dir / item.name
                 def _do_import_db(src, dst):
                     if dst.exists():
@@ -143,24 +321,79 @@ async def import_decrypted_directory(
                 yield _sse({"type": "progress", "percent": percent, "message": f"正在导入数据库: {item.name}"})
 
             # 4. 导入 resource 目录
-            resource_src = import_path_obj / "resource"
-            if resource_src.exists() and resource_src.is_dir():
+            resource_src = Path(info["resource_dir"]) if info.get("resource_dir") else None
+            if resource_src and resource_src.exists() and resource_src.is_dir():
                 yield _sse({"type": "progress", "percent": 30, "message": "正在导入资源文件 (这可能需要一些时间)..."})
                 resource_dst = account_output_dir / "resource"
                 
-                def _do_import_resource(src, dst):
+                def _reset_resource_dst(dst: Path) -> None:
                     if dst.exists():
                         if dst.is_symlink() or dst.is_file():
                             dst.unlink()
                         else:
                             shutil.rmtree(dst)
+
+                def _try_link_resource(src: Path, dst: Path) -> bool:
                     try:
                         os.symlink(src, dst, target_is_directory=True)
+                        return True
                     except Exception:
-                        shutil.copytree(src, dst, dirs_exist_ok=True)
-                
+                        return False
+
+                def _collect_resource_files(src: Path) -> list[tuple[Path, Path]]:
+                    files: list[tuple[Path, Path]] = []
+                    for root, _, names in os.walk(src):
+                        root_path = Path(root)
+                        for name in names:
+                            file_path = root_path / name
+                            try:
+                                if file_path.is_file():
+                                    files.append((file_path, file_path.relative_to(src)))
+                            except Exception:
+                                continue
+                    return files
+
+                def _copy_resource_batch(batch: list[tuple[Path, Path]], dst_root: Path) -> int:
+                    copied = 0
+                    for src_file, rel_path in batch:
+                        dst_file = dst_root / rel_path
+                        dst_file.parent.mkdir(parents=True, exist_ok=True)
+                        shutil.copy2(src_file, dst_file)
+                        copied += 1
+                    return copied
+
                 try:
-                    await asyncio.to_thread(_do_import_resource, resource_src, resource_dst)
+                    prefer_copy_resource = info.get("source_format") == "wxdump"
+                    await asyncio.to_thread(_reset_resource_dst, resource_dst)
+
+                    if not prefer_copy_resource:
+                        linked = await asyncio.to_thread(_try_link_resource, resource_src, resource_dst)
+                        if linked:
+                            yield _sse({"type": "progress", "percent": 48, "message": "资源目录已通过快捷链接导入。"})
+                        else:
+                            prefer_copy_resource = True
+
+                    if prefer_copy_resource:
+                        yield _sse({"type": "progress", "percent": 31, "message": "正在扫描资源文件数量..."})
+                        resource_files = await asyncio.to_thread(_collect_resource_files, resource_src)
+                        total_resources = len(resource_files)
+                        if total_resources <= 0:
+                            await asyncio.to_thread(resource_dst.mkdir, parents=True, exist_ok=True)
+                            yield _sse({"type": "progress", "percent": 48, "message": "资源目录为空，已跳过资源复制。"})
+                        else:
+                            await asyncio.to_thread(resource_dst.mkdir, parents=True, exist_ok=True)
+                            batch_size = 300
+                            copied_resources = 0
+                            for batch_start in range(0, total_resources, batch_size):
+                                _check_cancel()
+                                batch = resource_files[batch_start:batch_start + batch_size]
+                                copied_resources += await asyncio.to_thread(_copy_resource_batch, batch, resource_dst)
+                                percent = 31 + int(min(copied_resources, total_resources) / total_resources * 17)
+                                yield _sse({
+                                    "type": "progress",
+                                    "percent": min(percent, 48),
+                                    "message": f"正在复制资源文件：{copied_resources}/{total_resources}"
+                                })
                 except Exception as e:
                     logger.error(f"导入 resource 目录失败: {e}")
                 
@@ -183,6 +416,7 @@ async def import_decrypted_directory(
                         total_wxgf = len(wxgf_files)
                         converted_count = 0
                         for i, wxgf_path in enumerate(wxgf_files):
+                            _check_cancel()
                             def _convert_one(p):
                                 jpg_p = p.with_suffix(".wxgf.jpg")
                                 if not jpg_p.exists():
@@ -209,10 +443,26 @@ async def import_decrypted_directory(
                         
                         logger.info(f"账号 {account_name} 转换完成: {converted_count}/{total_wxgf} 个 .wxgf 文件")
                 
-            # 6. 复制 account.json
+            # 6. Copy or generate account.json
+            def _write_imported_account_json(dst: Path, info: dict) -> None:
+                src = Path(str(info.get("account_json_path") or ""))
+                target = dst / "account.json"
+                if src.exists() and src.is_file():
+                    shutil.copy2(src, target)
+                    return
+                payload = {
+                    "username": info.get("username") or dst.name,
+                    "nick": info.get("nick") or info.get("username") or dst.name,
+                    "avatar_url": info.get("avatar_url") or "",
+                    "alias": info.get("alias") or "",
+                    "generated_by": "manual_import",
+                    "source_format": info.get("source_format") or "unknown",
+                }
+                target.write_text(json.dumps(payload, ensure_ascii=False, indent=2), encoding="utf-8")
+
             yield _sse({"type": "progress", "percent": 85, "message": "正在更新账号配置..."})
             try:
-                await asyncio.to_thread(shutil.copy2, import_path_obj / "account.json", account_output_dir / "account.json")
+                await asyncio.to_thread(_write_imported_account_json, account_output_dir, info)
             except Exception:
                 pass
 
@@ -233,7 +483,7 @@ async def import_decrypted_directory(
                 )
 
             try:
-                await asyncio.to_thread(_save_source_info, account_output_dir, import_path_obj, info)
+                await asyncio.to_thread(_save_source_info, account_output_dir, Path(info.get("account_dir") or import_path_obj), info)
             except Exception:
                 pass
 
@@ -255,12 +505,32 @@ async def import_decrypted_directory(
                 "status": "success",
                 "account": account_name,
                 "nick": info["nick"],
-                "message": f"成功导入账号 {info['nick']} ({account_name})"
+                "message": f"成功导入账号 {info['nick']} ({account_name})",
+                "backup_dir": str(backup_dir) if backup_dir else ""
             })
 
+        except ImportCancelled:
+            try:
+                if account_output_dir is not None and backup_dir is not None:
+                    await asyncio.to_thread(_rollback_account_backup, account_output_dir, backup_dir)
+                    backup_restored = True
+            except Exception as rollback_error:
+                logger.error(f"取消导入后恢复备份失败: {rollback_error}", exc_info=True)
+            suffix = "，已恢复导入前备份" if backup_restored else ""
+            yield _sse({"type": "error", "message": f"导入已取消{suffix}"})
         except Exception as e:
-            logger.error(f"导入过程中发生异常: {e}", exc_info=True)
-            yield _sse({"type": "error", "message": f"导入失败: {str(e)}"})
+            logger.error(f"导入失败: {e}", exc_info=True)
+            try:
+                if account_output_dir is not None and backup_dir is not None:
+                    await asyncio.to_thread(_rollback_account_backup, account_output_dir, backup_dir)
+                    backup_restored = True
+            except Exception as rollback_error:
+                logger.error(f"导入失败后恢复备份失败: {rollback_error}", exc_info=True)
+            suffix = "，已恢复导入前备份" if backup_restored else ""
+            yield _sse({"type": "error", "message": f"导入失败: {str(e)}{suffix}"})
+        finally:
+            if job_key:
+                _IMPORT_CANCEL_EVENTS.pop(job_key, None)
 
     headers = {
         "Content-Type": "text/event-stream",