feat(desktop): 支持自定义 output 目录并迁移现有数据

- 支持在桌面端查看、选择和恢复默认 output 目录
- 安装器记录待应用目录，并在应用启动时自动迁移数据
- 后端支持 output 目录覆盖，补充桌面端与后端相关测试

desktop/scripts/installer-custom.nsh

@@ -1,6 +1,22 @@
 ; This file is included for both installer and uninstaller builds.
 ; Guard installer-only pages/functions to avoid "function not referenced" warnings
 ; when electron-builder compiles the standalone uninstaller.
+!define /ifndef WDA_DEFAULT_SETTINGS_PATH "$APPDATA\${APP_FILENAME}\desktop-settings.json"
+!define /ifndef WDA_DEFAULT_OUTPUT_DIR "$APPDATA\${APP_FILENAME}\output"
+!ifdef APP_PRODUCT_FILENAME
+!define /ifndef WDA_PRODUCT_SETTINGS_PATH "$APPDATA\${APP_PRODUCT_FILENAME}\desktop-settings.json"
+!define /ifndef WDA_PRODUCT_OUTPUT_DIR "$APPDATA\${APP_PRODUCT_FILENAME}\output"
+!else
+!define /ifndef WDA_PRODUCT_SETTINGS_PATH ""
+!define /ifndef WDA_PRODUCT_OUTPUT_DIR ""
+!endif
+!ifdef APP_PACKAGE_NAME
+!define /ifndef WDA_PACKAGE_SETTINGS_PATH "$APPDATA\${APP_PACKAGE_NAME}\desktop-settings.json"
+!define /ifndef WDA_PACKAGE_OUTPUT_DIR "$APPDATA\${APP_PACKAGE_NAME}\output"
+!else
+!define /ifndef WDA_PACKAGE_SETTINGS_PATH ""
+!define /ifndef WDA_PACKAGE_OUTPUT_DIR ""
+!endif
 !ifndef BUILD_UNINSTALLER
 !include nsDialogs.nsh
 !include LogicLib.nsh
@@ -13,6 +29,10 @@
 !define /ifndef MUI_DIRECTORYPAGE_TEXT_DESTINATION "安装位置："
 
 Var WDA_InstallDirPage
+Var WDA_OutputDirPage
+Var WDA_OutputDirInput
+Var WDA_OutputDirBrowseButton
+Var WDA_SelectedOutputDir
 
 !macro customInit
   ; Safety: older versions created an `output` junction inside the install directory that points to the
@@ -22,17 +42,10 @@ Var WDA_InstallDirPage
 !macroend
 
 !macro customInstall
-  ; Provide a safe, non-junction way for users to locate the real per-user output directory.
-  ; The actual data is NOT stored inside $INSTDIR (it is wiped on update/reinstall).
-  ; `open-output.cmd` uses %APPDATA% so it works for the current user.
-  FileOpen $0 "$INSTDIR\output-location.txt" w
-  FileWrite $0 "WeChatDataAnalysis output folder (per user):$\r$\n%APPDATA%\\${APP_PACKAGE_NAME}\\output$\r$\n"
-  FileClose $0
-
-  FileOpen $1 "$INSTDIR\open-output.cmd" w
-  ; NSIS escaping: use $\" to output a literal quote character into the .cmd file.
-  FileWrite $1 "@echo off$\r$\nexplorer $\"%APPDATA%\\${APP_PACKAGE_NAME}\\output$\"$\r$\n"
-  FileClose $1
+  ${If} $WDA_SelectedOutputDir == ""
+    Call WDA_InitOutputDirSelection
+  ${EndIf}
+  Call WDA_WritePendingOutputDirSetting
 !macroend
 
 Function WDA_RemoveLegacyOutputLink
@@ -47,9 +60,27 @@ FunctionEnd
   ; the final install location (includes the app sub-folder).
   !ifdef allowToChangeInstallationDirectory
     Page custom WDA_InstallDirPageCreate WDA_InstallDirPageLeave
+    Page custom WDA_OutputDirPageCreate WDA_OutputDirPageLeave
   !endif
 !macroend
 
+Function WDA_InitOutputDirSelection
+  StrCpy $WDA_SelectedOutputDir "${WDA_DEFAULT_OUTPUT_DIR}"
+  nsExec::ExecToStack '"$SYSDIR\WindowsPowerShell\v1.0\powershell.exe" -NoProfile -ExecutionPolicy Bypass -Command "& { param([string] $$defaultSettingsPath, [string] $$defaultOutputPath, [string] $$legacySettingsPath1, [string] $$legacySettingsPath2) $$candidates = @($$defaultSettingsPath, $$legacySettingsPath1, $$legacySettingsPath2) | Where-Object { -not [string]::IsNullOrWhiteSpace($$_) } | Select-Object -Unique; $$settingsPath = $$defaultSettingsPath; foreach ($$candidate in $$candidates) { if (Test-Path -LiteralPath $$candidate) { $$settingsPath = $$candidate; break } }; $$result = $$defaultOutputPath; if (Test-Path -LiteralPath $$settingsPath) { try { $$json = Get-Content -LiteralPath $$settingsPath -Raw | ConvertFrom-Json; $$value = [string] $$json.pendingOutputDir; if ([string]::IsNullOrWhiteSpace($$value)) { $$value = [string] $$json.outputDir }; if ($$value -eq '''') { $$result = $$defaultOutputPath } elseif (-not [string]::IsNullOrWhiteSpace($$value)) { $$result = $$value } } catch {} }; [Console]::OutputEncoding = [System.Text.Encoding]::UTF8; [Console]::Write($$result) }" "${WDA_DEFAULT_SETTINGS_PATH}" "${WDA_DEFAULT_OUTPUT_DIR}" "${WDA_PRODUCT_SETTINGS_PATH}" "${WDA_PACKAGE_SETTINGS_PATH}"'
+  Pop $0
+  Pop $1
+  ${If} $0 == "0"
+  ${AndIf} $1 != ""
+    StrCpy $WDA_SelectedOutputDir "$1"
+  ${EndIf}
+FunctionEnd
+
+Function WDA_WritePendingOutputDirSetting
+  nsExec::ExecToStack '"$SYSDIR\WindowsPowerShell\v1.0\powershell.exe" -NoProfile -ExecutionPolicy Bypass -Command "& { param([string] $$defaultSettingsPath, [string] $$defaultOutputPath, [string] $$selectedOutputPath, [string] $$legacySettingsPath1, [string] $$legacySettingsPath2) $$candidates = @($$defaultSettingsPath, $$legacySettingsPath1, $$legacySettingsPath2) | Where-Object { -not [string]::IsNullOrWhiteSpace($$_) } | Select-Object -Unique; $$sourceSettingsPath = $$defaultSettingsPath; foreach ($$candidate in $$candidates) { if (Test-Path -LiteralPath $$candidate) { $$sourceSettingsPath = $$candidate; break } }; if ([string]::IsNullOrWhiteSpace($$selectedOutputPath)) { $$selectedOutputPath = $$defaultOutputPath }; $$pending = if ([string]::Equals($$selectedOutputPath, $$defaultOutputPath, [System.StringComparison]::OrdinalIgnoreCase)) { '''' } else { $$selectedOutputPath }; $$obj = @{}; if (Test-Path -LiteralPath $$sourceSettingsPath) { try { $$existing = Get-Content -LiteralPath $$sourceSettingsPath -Raw | ConvertFrom-Json; if ($$null -ne $$existing) { $$existing.PSObject.Properties | ForEach-Object { $$obj[$$_.Name] = $$_.Value } } } catch {} }; $$obj[''pendingOutputDir''] = $$pending; $$dir = Split-Path -Parent $$defaultSettingsPath; New-Item -ItemType Directory -Force -Path $$dir | Out-Null; $$json = [PSCustomObject] $$obj | ConvertTo-Json -Depth 10; Set-Content -LiteralPath $$defaultSettingsPath -Value $$json -Encoding UTF8 }" "${WDA_DEFAULT_SETTINGS_PATH}" "${WDA_DEFAULT_OUTPUT_DIR}" "$WDA_SelectedOutputDir" "${WDA_PRODUCT_SETTINGS_PATH}" "${WDA_PACKAGE_SETTINGS_PATH}"'
+  Pop $0
+  Pop $1
+FunctionEnd
+
 Function WDA_EnsureAppSubDir
   ; Normalize $INSTDIR to always end with "\${APP_FILENAME}" (avoid cluttering a parent folder).
   StrCpy $0 "$INSTDIR"
@@ -105,6 +136,48 @@ FunctionEnd
 Function WDA_InstallDirPageLeave
 FunctionEnd
 
+Function WDA_OutputDirBrowse
+  nsDialogs::SelectFolderDialog "选择 output 目录" "$WDA_SelectedOutputDir"
+  Pop $0
+  ${If} $0 != error
+    StrCpy $WDA_SelectedOutputDir "$0"
+    ${NSD_SetText} $WDA_OutputDirInput "$0"
+  ${EndIf}
+FunctionEnd
+
+Function WDA_OutputDirPageCreate
+  Call WDA_InitOutputDirSelection
+
+  nsDialogs::Create 1018
+  Pop $WDA_OutputDirPage
+
+  ${If} $WDA_OutputDirPage == error
+    Abort
+  ${EndIf}
+
+  ${NSD_CreateLabel} 0u 0u 100% 24u "请选择 output 目录（保存解密数据库、导出内容、缓存、日志等）。"
+  Pop $0
+
+  ${NSD_CreateText} 0u 28u 78% 12u "$WDA_SelectedOutputDir"
+  Pop $WDA_OutputDirInput
+
+  ${NSD_CreateButton} 82% 27u 18% 14u "浏览..."
+  Pop $WDA_OutputDirBrowseButton
+  ${NSD_OnClick} $WDA_OutputDirBrowseButton WDA_OutputDirBrowse
+
+  ${NSD_CreateLabel} 0u 52u 100% 28u "安装器只记录你的选择；真正的数据迁移会在首次启动应用时执行。若目标目录已有内容，应用会阻止切换并提示处理。"
+  Pop $0
+
+  nsDialogs::Show
+FunctionEnd
+
+Function WDA_OutputDirPageLeave
+  ${NSD_GetText} $WDA_OutputDirInput $WDA_SelectedOutputDir
+  ${If} $WDA_SelectedOutputDir == ""
+    StrCpy $WDA_SelectedOutputDir "${WDA_DEFAULT_OUTPUT_DIR}"
+  ${EndIf}
+FunctionEnd
+
 !endif
 
 !ifdef BUILD_UNINSTALLER
@@ -177,6 +250,12 @@ FunctionEnd
         RMDir /r "$APPDATA\${APP_PACKAGE_NAME}"
       !endif
 
+      IfFileExists "$INSTDIR\output-location.path" 0 WDA_SkipCustomOutputDelete
+        nsExec::ExecToStack '"$SYSDIR\WindowsPowerShell\v1.0\powershell.exe" -NoProfile -ExecutionPolicy Bypass -Command "& { param([string] $$pathFile, [string] $$defaultPath1, [string] $$defaultPath2, [string] $$defaultPath3) if (Test-Path -LiteralPath $$pathFile) { $$target = (Get-Content -LiteralPath $$pathFile -Raw).Trim(); $$defaults = @($$defaultPath1, $$defaultPath2, $$defaultPath3) | Where-Object { -not [string]::IsNullOrWhiteSpace($$_) }; $$isDefault = $$false; foreach ($$defaultPath in $$defaults) { if ([string]::Equals($$target, $$defaultPath, [System.StringComparison]::OrdinalIgnoreCase)) { $$isDefault = $$true; break } }; if (-not $$isDefault -and -not [string]::IsNullOrWhiteSpace($$target) -and (Test-Path -LiteralPath $$target)) { Remove-Item -LiteralPath $$target -Recurse -Force -ErrorAction SilentlyContinue } } }" "$INSTDIR\output-location.path" "${WDA_DEFAULT_OUTPUT_DIR}" "${WDA_PRODUCT_OUTPUT_DIR}" "${WDA_PACKAGE_OUTPUT_DIR}"'
+        Pop $0
+        Pop $1
+      WDA_SkipCustomOutputDelete:
+
       ${if} $installMode == "all"
         SetShellVarContext all
       ${endif}

desktop/src/main.cjs

@@ -21,6 +21,13 @@ const fs = require("fs");
 const http = require("http");
 const net = require("net");
 const path = require("path");
+const {
+  getDefaultOutputDirPath,
+  getEffectiveOutputDirPath,
+  migrateOutputDirectory,
+  normalizeDirectoryPath,
+  rollbackOutputDirectoryChange,
+} = require("./output-dir.cjs");
 
 const DEFAULT_BACKEND_HOST = String(process.env.WECHAT_TOOL_HOST || "127.0.0.1").trim() || "127.0.0.1";
 const DEFAULT_BACKEND_PORT = parsePort(process.env.WECHAT_TOOL_PORT) ?? 10392;
@@ -32,6 +39,7 @@ let tray = null;
 let isQuitting = false;
 let desktopSettings = null;
 let backendPortChangeInProgress = false;
+let outputDirChangeInProgress = false;
 
 const gotSingleInstanceLock = app.requestSingleInstanceLock();
 if (!gotSingleInstanceLock) {
@@ -216,9 +224,76 @@ function resolveDataDir() {
 }
 
 function getUserDataDir() {
-  // Backwards-compat: we historically used Electron's userData directory for runtime storage.
-  // Keep this name but resolve to the effective data dir (can be overridden via env).
-  return resolveDataDir();
+  try {
+    const dir = app.getPath("userData");
+    if (!dir) return null;
+    fs.mkdirSync(dir, { recursive: true });
+    return dir;
+  } catch {
+    return null;
+  }
+}
+
+function safeNormalizeDirectory(value) {
+  try {
+    return normalizeDirectoryPath(value || "");
+  } catch {
+    return "";
+  }
+}
+
+function getDefaultOutputDir() {
+  const dataDir = resolveDataDir();
+  if (!dataDir) return null;
+  try {
+    return getDefaultOutputDirPath(dataDir);
+  } catch {
+    return null;
+  }
+}
+
+function syncOutputDirEnv(nextDir) {
+  const normalized = safeNormalizeDirectory(nextDir);
+  if (normalized) process.env.WECHAT_TOOL_OUTPUT_DIR = normalized;
+  else delete process.env.WECHAT_TOOL_OUTPUT_DIR;
+}
+
+function normalizePendingOutputDirValue(value) {
+  if (value == null) return null;
+  const text = String(value).trim();
+  if (!text) return "";
+  try {
+    return normalizeDirectoryPath(text);
+  } catch {
+    return null;
+  }
+}
+
+function resolveOutputDir() {
+  const dataDir = resolveDataDir();
+  if (!dataDir) return null;
+
+  const envOutputDir = safeNormalizeDirectory(process.env.WECHAT_TOOL_OUTPUT_DIR || "");
+  const settingsOutputDir = app.isPackaged ? safeNormalizeDirectory(loadDesktopSettings()?.outputDir || "") : "";
+
+  let chosen = null;
+  try {
+    chosen = getEffectiveOutputDirPath({
+      dataDir,
+      envOutputDir,
+      settingsOutputDir,
+    });
+  } catch {
+    chosen = getDefaultOutputDir();
+  }
+  if (!chosen) return null;
+
+  try {
+    fs.mkdirSync(chosen, { recursive: true });
+  } catch {}
+
+  syncOutputDirEnv(chosen);
+  return chosen;
 }
 
 function sanitizeAccountName(account) {
@@ -261,7 +336,8 @@ function resolveAccountDirInOutput(account) {
   const dataDir = resolveDataDir();
   if (!dataDir) throw new Error("无法定位数据目录");
 
-  const outputDir = path.join(dataDir, "output");
+  const outputDir = resolveOutputDir();
+  if (!outputDir) throw new Error("无法定位 output 目录");
   const databasesDir = path.join(outputDir, "databases");
   const accountName = sanitizeAccountName(account);
 
@@ -311,8 +387,8 @@ function getAccountInfoFromDisk(account) {
   };
 }
 
-function removeAccountFromKeyStore(dataDir, accountName) {
-  const keyStorePath = path.join(dataDir, "output", "account_keys.json");
+function removeAccountFromKeyStore(outputDir, accountName) {
+  const keyStorePath = path.join(outputDir, "account_keys.json");
   try {
     if (!fs.existsSync(keyStorePath)) return false;
     const raw = fs.readFileSync(keyStorePath, { encoding: "utf8" });
@@ -328,7 +404,7 @@ function removeAccountFromKeyStore(dataDir, accountName) {
 }
 
 async function deleteAccountDataFromDisk(account) {
-  const { dataDir, outputDir, databasesDir, accountName, accountDir } = resolveAccountDirInOutput(account);
+  const { outputDir, databasesDir, accountName, accountDir } = resolveAccountDirInOutput(account);
   if (!fs.existsSync(accountDir) || !fs.statSync(accountDir).isDirectory()) {
     throw new Error("账号数据不存在");
   }
@@ -348,7 +424,7 @@ async function deleteAccountDataFromDisk(account) {
     } catch {}
 
     fs.rmSync(accountDir, { recursive: true, force: true });
-    const removedKeyCache = removeAccountFromKeyStore(dataDir, accountName);
+    const removedKeyCache = removeAccountFromKeyStore(outputDir, accountName);
     const accounts = listDecryptedAccountsOnDisk(databasesDir);
     result = {
       status: "success",
@@ -394,10 +470,8 @@ function ensureOutputLink() {
   if (!app.isPackaged) return;
 
   const exeDir = getExeDir();
-  const dataDir = resolveDataDir();
-  if (!exeDir || !dataDir) return;
-
-  const target = path.join(dataDir, "output");
+  const target = resolveOutputDir();
+  if (!exeDir || !target) return;
   const legacyLinkPath = path.join(exeDir, "output");
 
   // Ensure the real output dir exists.
@@ -443,6 +517,11 @@ function ensureOutputLink() {
     fs.writeFileSync(p, text, { encoding: "utf8" });
   } catch {}
 
+  try {
+    const p = path.join(exeDir, "output-location.path");
+    fs.writeFileSync(p, `${target}\n`, { encoding: "utf8" });
+  } catch {}
+
   try {
     const p = path.join(exeDir, "open-output.cmd");
     const text = `@echo off\r\nexplorer \"${target}\"\r\n`;
@@ -510,6 +589,12 @@ function loadDesktopSettings() {
     ignoredUpdateVersion: "",
     // Backend (FastAPI) listens on this port. Used in packaged builds.
     backendPort: DEFAULT_BACKEND_PORT,
+    // Custom output dir; empty string means use the default dataDir/output.
+    outputDir: "",
+    // Pending output dir written by the installer before the next app startup.
+    pendingOutputDir: null,
+    // Last startup/apply failure when changing output dir.
+    lastOutputDirError: "",
     // Tracks the packaged UI build so we can invalidate Chromium's HTTP cache
     // after upgrades without wiping user data/localStorage.
     lastSeenUiBuildId: "",
@@ -530,6 +615,12 @@ function loadDesktopSettings() {
     const parsed = JSON.parse(raw || "{}");
     desktopSettings = { ...defaults, ...(parsed && typeof parsed === "object" ? parsed : {}) };
     desktopSettings.backendPort = parsePort(desktopSettings.backendPort) ?? defaults.backendPort;
+    desktopSettings.outputDir = safeNormalizeDirectory(desktopSettings.outputDir || "");
+    desktopSettings.pendingOutputDir =
+      parsed && typeof parsed === "object" && Object.prototype.hasOwnProperty.call(parsed, "pendingOutputDir")
+        ? normalizePendingOutputDirValue(parsed.pendingOutputDir)
+        : defaults.pendingOutputDir;
+    desktopSettings.lastOutputDirError = String(desktopSettings.lastOutputDirError || "").trim();
   } catch (err) {
     desktopSettings = { ...defaults };
     logMain(`[main] failed to load settings: ${err?.message || err}`);
@@ -551,6 +642,82 @@ function persistDesktopSettings() {
   }
 }
 
+function snapshotOutputDirSettings() {
+  loadDesktopSettings();
+  return {
+    outputDir: desktopSettings.outputDir,
+    pendingOutputDir: desktopSettings.pendingOutputDir,
+    lastOutputDirError: desktopSettings.lastOutputDirError,
+  };
+}
+
+function restoreOutputDirSettings(snapshot) {
+  loadDesktopSettings();
+  desktopSettings.outputDir = safeNormalizeDirectory(snapshot?.outputDir || "");
+  desktopSettings.pendingOutputDir = normalizePendingOutputDirValue(snapshot?.pendingOutputDir);
+  desktopSettings.lastOutputDirError = String(snapshot?.lastOutputDirError || "").trim();
+  const effectiveOutputDir = desktopSettings.outputDir || getDefaultOutputDir() || "";
+  syncOutputDirEnv(effectiveOutputDir);
+  persistDesktopSettings();
+}
+
+function setOutputDirSetting(nextDir) {
+  loadDesktopSettings();
+  const defaultDir = getDefaultOutputDir();
+  const normalized = safeNormalizeDirectory(nextDir || "");
+  if (!normalized || (defaultDir && normalized === defaultDir)) {
+    desktopSettings.outputDir = "";
+  } else {
+    desktopSettings.outputDir = normalized;
+  }
+  syncOutputDirEnv(desktopSettings.outputDir || defaultDir || "");
+  persistDesktopSettings();
+  return desktopSettings.outputDir;
+}
+
+function setPendingOutputDirSetting(nextDir) {
+  loadDesktopSettings();
+  desktopSettings.pendingOutputDir = normalizePendingOutputDirValue(nextDir);
+  persistDesktopSettings();
+  return desktopSettings.pendingOutputDir;
+}
+
+function clearPendingOutputDirSetting() {
+  loadDesktopSettings();
+  desktopSettings.pendingOutputDir = null;
+  persistDesktopSettings();
+}
+
+function setOutputDirLastError(message) {
+  loadDesktopSettings();
+  desktopSettings.lastOutputDirError = String(message || "").trim();
+  persistDesktopSettings();
+  return desktopSettings.lastOutputDirError;
+}
+
+function getOutputDirInfo() {
+  loadDesktopSettings();
+  const defaultPath = getDefaultOutputDir() || "";
+  const currentPath = resolveOutputDir() || defaultPath;
+  const hasPending = desktopSettings.pendingOutputDir !== null;
+  const pendingPath =
+    desktopSettings.pendingOutputDir === null
+      ? ""
+      : desktopSettings.pendingOutputDir === ""
+        ? defaultPath
+        : safeNormalizeDirectory(desktopSettings.pendingOutputDir);
+  return {
+    path: currentPath || "",
+    defaultPath,
+    isDefault: !!currentPath && !!defaultPath && currentPath === defaultPath,
+    pendingPath,
+    hasPending,
+    lastError: String(desktopSettings.lastOutputDirError || "").trim(),
+    canChange: !!app.isPackaged,
+    changeUnavailableReason: app.isPackaged ? "" : "开发模式不支持界面修改 output 目录",
+  };
+}
+
 function getCloseBehavior() {
   const v = String(loadDesktopSettings()?.closeBehavior || "").trim().toLowerCase();
   return v === "exit" ? "exit" : "tray";
@@ -576,6 +743,137 @@ function setIgnoredUpdateVersion(version) {
   return desktopSettings.ignoredUpdateVersion;
 }
 
+async function applyOutputDirChange(nextValue) {
+  if (!app.isPackaged) {
+    throw new Error("开发模式不支持界面修改 output 目录");
+  }
+
+  const defaultPath = getDefaultOutputDir();
+  const currentPath = resolveOutputDir();
+  if (!defaultPath || !currentPath) {
+    throw new Error("无法定位 output 目录");
+  }
+
+  const rawText = String(nextValue ?? "").trim();
+  const nextPath = rawText ? normalizeDirectoryPath(rawText) : defaultPath;
+  const previousSettings = snapshotOutputDirSettings();
+
+  if (nextPath === currentPath) {
+    setOutputDirSetting(nextPath);
+    clearPendingOutputDirSetting();
+    setOutputDirLastError("");
+    ensureOutputLink();
+    const info = getOutputDirInfo();
+    return {
+      success: true,
+      changed: false,
+      path: info.path,
+      defaultPath: info.defaultPath,
+      isDefault: info.isDefault,
+      pendingPath: info.pendingPath,
+      backupPath: "",
+      sourceWasEmpty: false,
+      message: "output 目录未变化",
+    };
+  }
+
+  const wasBackendRunning = !!backendProc;
+  let migration = null;
+  let settingsSwitched = false;
+
+  try {
+    if (wasBackendRunning) {
+      await stopBackendAndWait({ timeoutMs: 10_000 });
+    }
+
+    migration = migrateOutputDirectory({
+      currentDir: currentPath,
+      nextDir: nextPath,
+    });
+
+    setOutputDirSetting(nextPath);
+    clearPendingOutputDirSetting();
+    setOutputDirLastError("");
+    settingsSwitched = true;
+    ensureOutputLink();
+
+    if (wasBackendRunning) {
+      startBackend();
+      await waitForBackend({ timeoutMs: 30_000 });
+    }
+
+    const info = getOutputDirInfo();
+    return {
+      success: true,
+      changed: true,
+      path: info.path,
+      defaultPath: info.defaultPath,
+      isDefault: info.isDefault,
+      pendingPath: info.pendingPath,
+      backupPath: migration?.backupDir || "",
+      sourceWasEmpty: !!migration?.sourceWasEmpty,
+      message: migration?.sourceWasEmpty ? "output 目录已切换" : "output 目录已迁移并切换",
+    };
+  } catch (err) {
+    const message = err?.message || String(err);
+    let rollbackMessage = "";
+    if (migration?.changed) {
+      try {
+        rollbackOutputDirectoryChange({
+          previousDir: currentPath,
+          currentDir: nextPath,
+          backupDir: migration.backupDir,
+          sourceWasEmpty: migration.sourceWasEmpty,
+        });
+      } catch (rollbackErr) {
+        logMain(`[main] output dir rollback failed: ${rollbackErr?.message || rollbackErr}`);
+        rollbackMessage = `；回滚失败：${rollbackErr?.message || rollbackErr}`;
+        if (migration?.backupDir) {
+          rollbackMessage += `；备份目录：${migration.backupDir}`;
+        }
+      }
+    }
+
+    if (settingsSwitched) {
+      restoreOutputDirSettings(previousSettings);
+    } else {
+      syncOutputDirEnv(currentPath);
+    }
+    ensureOutputLink();
+
+    if (wasBackendRunning) {
+      try {
+        startBackend();
+        await waitForBackend({ timeoutMs: 30_000 });
+      } catch (restartErr) {
+        throw new Error(
+          `切换 output 目录失败：${message}${rollbackMessage}；且旧后端恢复失败：${restartErr?.message || restartErr}`
+        );
+      }
+    }
+
+    if (rollbackMessage) {
+      throw new Error(`切换 output 目录失败：${message}${rollbackMessage}`);
+    }
+    throw err;
+  }
+}
+
+async function applyPendingOutputDirOnStartup() {
+  if (!app.isPackaged) return;
+  loadDesktopSettings();
+  if (desktopSettings.pendingOutputDir === null) return;
+
+  try {
+    await applyOutputDirChange(desktopSettings.pendingOutputDir);
+  } catch (err) {
+    clearPendingOutputDirSetting();
+    setOutputDirLastError(`安装时设置的 output 目录未能应用：${err?.message || err}`);
+    ensureOutputLink();
+    logMain(`[main] failed to apply pending output dir: ${err?.message || err}`);
+  }
+}
+
 async function refreshRendererCacheForPackagedUi() {
   if (!app.isPackaged) return;
 
@@ -1171,11 +1469,11 @@ function startBackend() {
   }
 
   if (app.isPackaged) {
-    if (!env.WECHAT_TOOL_DATA_DIR) {
-      env.WECHAT_TOOL_DATA_DIR = app.getPath("userData");
-    }
+    env.WECHAT_TOOL_DATA_DIR = resolveDataDir() || app.getPath("userData");
+    env.WECHAT_TOOL_OUTPUT_DIR = resolveOutputDir() || getDefaultOutputDir() || path.join(env.WECHAT_TOOL_DATA_DIR, "output");
     try {
       fs.mkdirSync(env.WECHAT_TOOL_DATA_DIR, { recursive: true });
+      fs.mkdirSync(env.WECHAT_TOOL_OUTPUT_DIR, { recursive: true });
     } catch {}
 
     const backendExe = getPackagedBackendPath();
@@ -1689,16 +1987,31 @@ function registerWindowIpc() {
     }
   });
 
+  ipcMain.handle("app:getOutputDirInfo", () => {
+    try {
+      return getOutputDirInfo();
+    } catch (err) {
+      logMain(`[main] app:getOutputDirInfo failed: ${err?.message || err}`);
+      return {
+        path: "",
+        defaultPath: "",
+        isDefault: true,
+        pendingPath: "",
+        hasPending: false,
+        lastError: err?.message || String(err),
+        canChange: !!app.isPackaged,
+        changeUnavailableReason: app.isPackaged ? "" : "开发模式不支持界面修改 output 目录",
+      };
+    }
+  });
+
   ipcMain.handle("app:getOutputDir", () => {
-    const dir = resolveDataDir();
-    if (!dir) return "";
-    return path.join(dir, "output");
+    return resolveOutputDir() || "";
   });
 
   ipcMain.handle("app:openOutputDir", async () => {
-    const dir = resolveDataDir();
-    if (!dir) throw new Error("无法定位数据目录");
-    const outDir = path.join(dir, "output");
+    const outDir = resolveOutputDir();
+    if (!outDir) throw new Error("无法定位 output 目录");
     try {
       fs.mkdirSync(outDir, { recursive: true });
     } catch {}
@@ -1713,6 +2026,28 @@ function registerWindowIpc() {
     }
   });
 
+  ipcMain.handle("app:setOutputDir", async (_event, nextDir) => {
+    if (outputDirChangeInProgress) {
+      return {
+        success: false,
+        error: "output 目录切换中，请稍后重试",
+      };
+    }
+    outputDirChangeInProgress = true;
+    try {
+      return await applyOutputDirChange(nextDir);
+    } catch (err) {
+      const message = err?.message || String(err);
+      logMain(`[main] app:setOutputDir failed: ${message}`);
+      return {
+        success: false,
+        error: message,
+      };
+    } finally {
+      outputDirChangeInProgress = false;
+    }
+  });
+
   ipcMain.handle("app:getAccountInfo", async (_event, account) => {
     try {
       return getAccountInfoFromDisk(account);
@@ -1796,6 +2131,8 @@ async function main() {
   // Resolve/create the data dir early so we can log reliably and place helper files
   // next to the installed exe for easier access.
   resolveDataDir();
+  loadDesktopSettings();
+  await applyPendingOutputDirOnStartup();
   ensureOutputLink();
   await ensureBackendPortAvailableOnStartup();
 
@@ -1876,10 +2213,20 @@ if (gotSingleInstanceLock) {
     stopBackend();
     try {
       const dir = getUserDataDir();
+      const outputDir = resolveOutputDir();
       if (dir) {
+        const detailLines = [
+          `启动失败：${err?.message || err}`,
+          "",
+          `桌面日志目录：${dir}`,
+          "文件：desktop-main.log / backend-stdio.log",
+        ];
+        if (outputDir) {
+          detailLines.push("", `当前 output 目录：${outputDir}`, "其中 output\\logs\\... 也在这里");
+        }
         dialog.showErrorBox(
           "WeChatDataAnalysis 启动失败",
-          `启动失败：${err?.message || err}\n\n请查看日志目录：\n${dir}\n\n文件：desktop-main.log / backend-stdio.log / output\\\\logs\\\\...`
+          detailLines.join("\n")
         );
         shell.openPath(dir);
       }

desktop/src/output-dir.cjs

@@ -0,0 +1,252 @@
+const fs = require("fs");
+const path = require("path");
+
+const SENTINEL_NAMES = [
+  "account_keys.json",
+  "runtime_settings.json",
+  "message_edits.db",
+  "databases",
+  "exports",
+  "logs",
+];
+
+function normalizeDirectoryPath(value) {
+  const text = String(value || "").trim();
+  if (!text) return "";
+  const expanded = text.replace(/^~(?=$|[\\/])/, process.env.USERPROFILE || process.env.HOME || "~");
+  if (!path.isAbsolute(expanded)) {
+    throw new Error("output 目录必须使用绝对路径");
+  }
+  return path.resolve(expanded);
+}
+
+function getDefaultOutputDirPath(dataDir) {
+  const base = normalizeDirectoryPath(dataDir);
+  if (!base) throw new Error("无法定位数据目录");
+  return path.join(base, "output");
+}
+
+function getEffectiveOutputDirPath({ dataDir, envOutputDir, settingsOutputDir }) {
+  const envPath = normalizeDirectoryPath(envOutputDir || "");
+  if (envPath) return envPath;
+
+  const settingsPath = normalizeDirectoryPath(settingsOutputDir || "");
+  if (settingsPath) return settingsPath;
+
+  return getDefaultOutputDirPath(dataDir);
+}
+
+function hasDirectoryContents(dirPath) {
+  try {
+    return fs.readdirSync(dirPath).length > 0;
+  } catch (err) {
+    if (err && err.code === "ENOENT") return false;
+    throw err;
+  }
+}
+
+function pathExists(dirPath) {
+  try {
+    fs.accessSync(dirPath);
+    return true;
+  } catch {
+    return false;
+  }
+}
+
+function isDirectory(dirPath) {
+  try {
+    return fs.statSync(dirPath).isDirectory();
+  } catch {
+    return false;
+  }
+}
+
+function isPathInside(parentPath, candidatePath) {
+  const parent = path.resolve(parentPath);
+  const candidate = path.resolve(candidatePath);
+  if (parent === candidate) return false;
+  const relative = path.relative(parent, candidate);
+  return !!relative && !relative.startsWith("..") && !path.isAbsolute(relative);
+}
+
+function collectSentinels(sourceDir) {
+  const sentinels = [];
+  for (const name of SENTINEL_NAMES) {
+    const sourcePath = path.join(sourceDir, name);
+    if (!pathExists(sourcePath)) continue;
+    sentinels.push({
+      name,
+      isDir: isDirectory(sourcePath),
+      size: !isDirectory(sourcePath) ? fs.statSync(sourcePath).size : null,
+    });
+  }
+  return sentinels;
+}
+
+function verifyCopiedOutputTree(sourceDir, copiedDir) {
+  const sentinels = collectSentinels(sourceDir);
+  for (const item of sentinels) {
+    const copiedPath = path.join(copiedDir, item.name);
+    if (!pathExists(copiedPath)) {
+      throw new Error(`迁移校验失败：缺少 ${item.name}`);
+    }
+    if (item.isDir) {
+      if (!isDirectory(copiedPath)) {
+        throw new Error(`迁移校验失败：${item.name} 不是目录`);
+      }
+      continue;
+    }
+    const copiedStat = fs.statSync(copiedPath);
+    if (copiedStat.size !== item.size) {
+      throw new Error(`迁移校验失败：${item.name} 大小不一致`);
+    }
+  }
+}
+
+function makeTimestamp(now = new Date()) {
+  const parts = [
+    now.getFullYear(),
+    String(now.getMonth() + 1).padStart(2, "0"),
+    String(now.getDate()).padStart(2, "0"),
+    String(now.getHours()).padStart(2, "0"),
+    String(now.getMinutes()).padStart(2, "0"),
+    String(now.getSeconds()).padStart(2, "0"),
+  ];
+  return parts.join("");
+}
+
+function makeUniqueSiblingPath(basePath, suffix, now = new Date()) {
+  const stamp = makeTimestamp(now);
+  let attempt = 0;
+  while (true) {
+    const candidate = `${basePath}.${suffix}-${stamp}${attempt ? `-${attempt}` : ""}`;
+    if (!pathExists(candidate)) return candidate;
+    attempt += 1;
+  }
+}
+
+function ensureTargetIsUsable(targetDir) {
+  if (!pathExists(targetDir)) return;
+  if (!isDirectory(targetDir)) {
+    throw new Error("目标 output 路径已存在且不是目录");
+  }
+  if (hasDirectoryContents(targetDir)) {
+    throw new Error("目标 output 目录已有内容，请先清空后再重试");
+  }
+}
+
+function migrateOutputDirectory({ currentDir, nextDir, now = new Date() }) {
+  const currentPath = normalizeDirectoryPath(currentDir);
+  const targetPath = normalizeDirectoryPath(nextDir);
+  if (!currentPath || !targetPath) {
+    throw new Error("output 路径不能为空");
+  }
+  if (currentPath === targetPath) {
+    return {
+      changed: false,
+      currentDir: currentPath,
+      targetDir: targetPath,
+      sourceWasEmpty: !hasDirectoryContents(currentPath),
+      backupDir: "",
+    };
+  }
+  if (isPathInside(currentPath, targetPath) || isPathInside(targetPath, currentPath)) {
+    throw new Error("新旧 output 路径不能互相包含");
+  }
+
+  ensureTargetIsUsable(targetPath);
+
+  const sourceExists = pathExists(currentPath);
+  if (sourceExists && !isDirectory(currentPath)) {
+    throw new Error("当前 output 路径不是目录");
+  }
+  const sourceWasEmpty = !sourceExists || !hasDirectoryContents(currentPath);
+  if (sourceWasEmpty) {
+    fs.mkdirSync(targetPath, { recursive: true });
+    return {
+      changed: true,
+      currentDir: currentPath,
+      targetDir: targetPath,
+      sourceWasEmpty: true,
+      backupDir: "",
+    };
+  }
+
+  const tempTarget = makeUniqueSiblingPath(targetPath, "migrating", now);
+  const backupDir = makeUniqueSiblingPath(currentPath, "backup", now);
+
+  fs.cpSync(currentPath, tempTarget, {
+    recursive: true,
+    force: false,
+    errorOnExist: true,
+    preserveTimestamps: true,
+  });
+
+  try {
+    verifyCopiedOutputTree(currentPath, tempTarget);
+    if (pathExists(targetPath)) {
+      fs.rmSync(targetPath, { recursive: true, force: true });
+    }
+
+    fs.renameSync(currentPath, backupDir);
+    try {
+      fs.renameSync(tempTarget, targetPath);
+    } catch (err) {
+      try {
+        if (!pathExists(currentPath) && pathExists(backupDir)) {
+          fs.renameSync(backupDir, currentPath);
+        }
+      } catch {}
+      throw err;
+    }
+  } catch (err) {
+    try {
+      if (pathExists(tempTarget)) {
+        fs.rmSync(tempTarget, { recursive: true, force: true });
+      }
+    } catch {}
+    throw err;
+  }
+
+  return {
+    changed: true,
+    currentDir: currentPath,
+    targetDir: targetPath,
+    sourceWasEmpty: false,
+    backupDir,
+  };
+}
+
+function rollbackOutputDirectoryChange({ previousDir, currentDir, backupDir, sourceWasEmpty }) {
+  const previousPath = normalizeDirectoryPath(previousDir);
+  const currentPath = normalizeDirectoryPath(currentDir);
+
+  try {
+    if (currentPath && pathExists(currentPath)) {
+      fs.rmSync(currentPath, { recursive: true, force: true });
+    }
+  } catch {}
+
+  if (sourceWasEmpty) {
+    return;
+  }
+
+  const backupPath = normalizeDirectoryPath(backupDir);
+  if (!backupPath || !pathExists(backupPath)) return;
+
+  try {
+    if (!pathExists(previousPath)) {
+      fs.renameSync(backupPath, previousPath);
+    }
+  } catch {}
+}
+
+module.exports = {
+  getDefaultOutputDirPath,
+  getEffectiveOutputDirPath,
+  hasDirectoryContents,
+  migrateOutputDirectory,
+  normalizeDirectoryPath,
+  rollbackOutputDirectoryChange,
+};

desktop/src/preload.cjs

@@ -82,7 +82,9 @@ contextBridge.exposeInMainWorld("wechatDesktop", {
   chooseDirectory: (options = {}) => ipcRenderer.invoke("dialog:chooseDirectory", options),
 
   // Data/output folder helpers
+  getOutputDirInfo: () => ipcRenderer.invoke("app:getOutputDirInfo"),
   getOutputDir: () => ipcRenderer.invoke("app:getOutputDir"),
+  setOutputDir: (dir) => ipcRenderer.invoke("app:setOutputDir", String(dir ?? "")),
   openOutputDir: () => ipcRenderer.invoke("app:openOutputDir"),
   getAccountInfo: (account) => ipcRenderer.invoke("app:getAccountInfo", String(account || "")),
   deleteAccountData: (account) => ipcRenderer.invoke("app:deleteAccountData", String(account || "")),

desktop/tests/output-dir.test.cjs

@@ -0,0 +1,162 @@
+const test = require("node:test");
+const assert = require("node:assert/strict");
+const fs = require("fs");
+const os = require("os");
+const path = require("path");
+
+const {
+  getDefaultOutputDirPath,
+  getEffectiveOutputDirPath,
+  migrateOutputDirectory,
+  normalizeDirectoryPath,
+  rollbackOutputDirectoryChange,
+} = require("../src/output-dir.cjs");
+
+function makeTempDir() {
+  return fs.mkdtempSync(path.join(os.tmpdir(), "wda-output-"));
+}
+
+function cleanupDir(dirPath) {
+  try {
+    fs.rmSync(dirPath, { recursive: true, force: true });
+  } catch {}
+}
+
+test("normalizeDirectoryPath requires absolute paths", () => {
+  assert.throws(() => normalizeDirectoryPath("relative/path"), /绝对路径/);
+});
+
+test("getEffectiveOutputDirPath prefers env, then settings, then default", () => {
+  const root = makeTempDir();
+  const envDir = path.join(root, "env-output");
+  const settingsDir = path.join(root, "settings-output");
+  const defaultDir = path.join(root, "data", "output");
+
+  try {
+    assert.equal(
+      getEffectiveOutputDirPath({
+        dataDir: path.join(root, "data"),
+        envOutputDir: envDir,
+        settingsOutputDir: settingsDir,
+      }),
+      path.resolve(envDir)
+    );
+    assert.equal(
+      getEffectiveOutputDirPath({
+        dataDir: path.join(root, "data"),
+        envOutputDir: "",
+        settingsOutputDir: settingsDir,
+      }),
+      path.resolve(settingsDir)
+    );
+    assert.equal(getDefaultOutputDirPath(path.join(root, "data")), path.resolve(defaultDir));
+  } finally {
+    cleanupDir(root);
+  }
+});
+
+test("migrateOutputDirectory switches empty source to a new directory", () => {
+  const root = makeTempDir();
+  const currentDir = path.join(root, "current-output");
+  const nextDir = path.join(root, "custom-output");
+
+  try {
+    fs.mkdirSync(currentDir, { recursive: true });
+    const result = migrateOutputDirectory({ currentDir, nextDir });
+    assert.equal(result.changed, true);
+    assert.equal(result.sourceWasEmpty, true);
+    assert.equal(result.backupDir, "");
+    assert.ok(fs.existsSync(nextDir));
+    assert.equal(fs.existsSync(currentDir), true);
+  } finally {
+    cleanupDir(root);
+  }
+});
+
+test("migrateOutputDirectory blocks non-empty targets", () => {
+  const root = makeTempDir();
+  const currentDir = path.join(root, "current-output");
+  const nextDir = path.join(root, "custom-output");
+
+  try {
+    fs.mkdirSync(path.join(currentDir, "logs"), { recursive: true });
+    fs.writeFileSync(path.join(currentDir, "runtime_settings.json"), "{}");
+    fs.mkdirSync(nextDir, { recursive: true });
+    fs.writeFileSync(path.join(nextDir, "existing.txt"), "occupied");
+
+    assert.throws(
+      () => migrateOutputDirectory({ currentDir, nextDir }),
+      /已有内容/
+    );
+  } finally {
+    cleanupDir(root);
+  }
+});
+
+test("migrateOutputDirectory blocks invalid current paths", () => {
+  const root = makeTempDir();
+  const currentDir = path.join(root, "current-output");
+  const nextDir = path.join(root, "custom-output");
+
+  try {
+    fs.writeFileSync(currentDir, "not-a-directory");
+    assert.throws(
+      () => migrateOutputDirectory({ currentDir, nextDir }),
+      /不是目录/
+    );
+  } finally {
+    cleanupDir(root);
+  }
+});
+
+test("migrateOutputDirectory copies data and leaves the old directory as a backup", () => {
+  const root = makeTempDir();
+  const currentDir = path.join(root, "current-output");
+  const nextDir = path.join(root, "custom-output");
+
+  try {
+    fs.mkdirSync(path.join(currentDir, "databases", "wxid_test"), { recursive: true });
+    fs.writeFileSync(path.join(currentDir, "runtime_settings.json"), "{\"backend_port\":10392}");
+    fs.writeFileSync(path.join(currentDir, "databases", "wxid_test", "session.db"), "session");
+    fs.writeFileSync(path.join(currentDir, "databases", "wxid_test", "contact.db"), "contact");
+
+    const result = migrateOutputDirectory({ currentDir, nextDir, now: new Date("2026-03-30T08:00:00Z") });
+    assert.equal(result.changed, true);
+    assert.equal(result.sourceWasEmpty, false);
+    assert.match(path.basename(result.backupDir), /^current-output\.backup-\d{14}$/);
+    assert.ok(fs.existsSync(nextDir));
+    assert.ok(fs.existsSync(path.join(nextDir, "runtime_settings.json")));
+    assert.ok(fs.existsSync(path.join(nextDir, "databases", "wxid_test", "session.db")));
+    assert.ok(fs.existsSync(result.backupDir));
+    assert.equal(fs.existsSync(currentDir), false);
+  } finally {
+    cleanupDir(root);
+  }
+});
+
+test("rollbackOutputDirectoryChange restores the previous directory", () => {
+  const root = makeTempDir();
+  const previousDir = path.join(root, "current-output");
+  const currentDir = path.join(root, "custom-output");
+  const backupDir = path.join(root, "current-output.backup-20260330080100");
+
+  try {
+    fs.mkdirSync(path.join(currentDir, "databases"), { recursive: true });
+    fs.writeFileSync(path.join(currentDir, "databases", "temp.db"), "temp");
+    fs.mkdirSync(path.join(backupDir, "databases"), { recursive: true });
+    fs.writeFileSync(path.join(backupDir, "databases", "session.db"), "restored");
+
+    rollbackOutputDirectoryChange({
+      previousDir,
+      currentDir,
+      backupDir,
+      sourceWasEmpty: false,
+    });
+
+    assert.equal(fs.existsSync(currentDir), false);
+    assert.ok(fs.existsSync(path.join(previousDir, "databases", "session.db")));
+    assert.equal(fs.existsSync(backupDir), false);
+  } finally {
+    cleanupDir(root);
+  }
+});

frontend/components/SettingsDialog.vue

@@ -4,9 +4,9 @@
     class="settings-dialog fixed inset-0 z-[120] flex items-center justify-center bg-black/40 px-4 py-4 backdrop-blur-md sm:py-8"
     @click.self="handleClose"
   >
-    <div class="settings-dialog-panel flex h-[80vh] min-h-[380px] w-full max-w-[760px] overflow-hidden rounded-[10px] border border-[#e2e2e2] bg-white shadow-2xl">
+    <div class="settings-dialog-panel flex h-[80vh] min-h-[380px] w-full max-w-[880px] overflow-hidden rounded-[10px] border border-[#e2e2e2] bg-white shadow-2xl">
       <!-- Sidebar -->
-      <aside class="flex w-[180px] shrink-0 flex-col bg-[#fcfcfc] border-r border-[#eeeeee]">
+      <aside class="flex w-[160px] shrink-0 flex-col bg-[#fcfcfc] border-r border-[#eeeeee]">
         <div class="mt-4 mb-2 flex items-center px-4 gap-2">
           <div class="flex h-6 w-6 items-center justify-center rounded-[5px] bg-[#e7f5ee] text-[#07b75b]">
             <svg class="h-[15px] w-[15px]" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.8" stroke-linecap="round" stroke-linejoin="round">
@@ -149,19 +149,74 @@
               </div>
 
               <div class="px-3.5 py-3">
-                <div class="flex flex-col gap-1.5 sm:flex-row sm:items-center sm:justify-between">
-                  <div class="min-w-0 flex-1">
-                    <div class="text-[13px] font-medium text-[#222]">output 目录</div>
-                    <div class="mt-0.5 text-[11px] text-[#909090] break-words">{{ desktopOutputDirText }}</div>
+                <div class="flex flex-col gap-2.5">
+                  <div class="flex flex-col gap-1.5 sm:flex-row sm:items-center sm:justify-between">
+                    <div class="min-w-0 flex-1">
+                      <div class="text-[13px] font-medium text-[#222]">output 目录</div>
+                      <div class="mt-0.5 text-[11px] text-[#909090] break-words">
+                        当前：{{ desktopOutputDirText }}
+                        <span class="ml-1 text-[#666]">{{ desktopOutputDirIsDefault ? '（默认位置）' : '（自定义位置）' }}</span>
+                      </div>
+                      <div class="mt-0.5 text-[11px] text-[#909090] break-words">默认：{{ desktopOutputDirDefaultText }}</div>
+                      <div v-if="desktopOutputDirPendingText" class="mt-0.5 text-[11px] text-amber-700 break-words">
+                        待应用：{{ desktopOutputDirPendingText }}
+                      </div>
+                      <div v-if="desktopOutputDirUnavailableReason" class="mt-1 text-[11px] text-amber-700 break-words">
+                        {{ desktopOutputDirUnavailableReason }}
+                      </div>
+                    </div>
+                    <button
+                      type="button"
+                      class="shrink-0 rounded-[6px] border border-[#e2e2e2] bg-white px-2 py-1 text-[12px] text-[#222] transition hover:bg-[#f9f9f9] disabled:cursor-not-allowed disabled:opacity-50"
+                      :disabled="!isDesktopEnv || desktopOutputDirLoading || desktopOutputDirApplying"
+                      @click="onDesktopOpenOutputDir"
+                    >
+                      打开当前 output
+                    </button>
+                  </div>
+                  <div class="flex flex-col gap-1.5 sm:flex-row sm:items-center">
+                    <input
+                      v-model="desktopOutputDirInput"
+                      type="text"
+                      spellcheck="false"
+                      class="min-w-0 flex-1 rounded-[6px] border border-[#e2e2e2] bg-white px-2.5 py-1.5 text-[12px] text-[#333] outline-none transition focus:border-[#07b75b] focus:ring-1 focus:ring-[#07b75b]/30"
+                      :disabled="desktopOutputDirControlsDisabled"
+                      :placeholder="desktopOutputDirCanChange ? '选择新的 output 目录' : '当前环境不支持修改 output 目录'"
+                      @keyup.enter="onDesktopOutputDirApply"
+                    />
+                    <div class="flex shrink-0 items-center gap-1.5">
+                      <button
+                        type="button"
+                        class="rounded-[6px] border border-[#e2e2e2] bg-white px-2 py-1 text-[12px] text-[#222] transition hover:bg-[#f9f9f9] disabled:cursor-not-allowed disabled:opacity-50"
+                        :disabled="desktopOutputDirControlsDisabled"
+                        @click="onDesktopChooseOutputDir"
+                      >
+                        选择文件夹
+                      </button>
+                      <button
+                        type="button"
+                        class="rounded-[6px] border border-[#e2e2e2] bg-white px-2 py-1 text-[12px] text-[#222] transition hover:bg-[#f9f9f9] disabled:cursor-not-allowed disabled:opacity-50"
+                        :disabled="desktopOutputDirControlsDisabled"
+                        @click="onDesktopOutputDirApply"
+                      >
+                        {{ desktopOutputDirApplying ? '迁移中...' : '应用' }}
+                      </button>
+                      <button
+                        type="button"
+                        class="rounded-[6px] border border-[#e2e2e2] bg-white px-2 py-1 text-[12px] text-[#222] transition hover:bg-[#f9f9f9] disabled:cursor-not-allowed disabled:opacity-50"
+                        :disabled="desktopOutputDirControlsDisabled"
+                        @click="onDesktopOutputDirReset"
+                      >
+                        恢复默认
+                      </button>
+                    </div>
+                  </div>
+                  <div v-if="desktopOutputDirCanChange" class="text-[11px] text-[#909090]">
+                    修改后会迁移整个 output 目录；如果目标目录已有内容，会先阻止并提示。
+                  </div>
+                  <div v-if="desktopOutputDirMessage" class="rounded-[6px] border border-[#d8efe2] bg-[#f4fbf7] px-2.5 py-1.5 text-[11px] text-[#1b6b43] whitespace-pre-wrap">
+                    {{ desktopOutputDirMessage }}
                   </div>
-                  <button
-                    type="button"
-                    class="shrink-0 rounded-[6px] border border-[#e2e2e2] bg-white px-2 py-1 text-[12px] text-[#222] transition hover:bg-[#f9f9f9] disabled:cursor-not-allowed disabled:opacity-50"
-                    :disabled="!isDesktopEnv || desktopOutputDirLoading"
-                    @click="onDesktopOpenOutputDir"
-                  >
-                    打开 output
-                  </button>
                 </div>
                 <div v-if="desktopOutputDirError" class="mt-1.5 text-[11px] text-red-600 whitespace-pre-wrap">
                   {{ desktopOutputDirError }}
@@ -345,13 +400,33 @@ const desktopBackendPortError = ref('')
 const desktopBackendPortDefault = ref(10392)
 
 const desktopOutputDir = ref('')
+const desktopOutputDirDefault = ref('')
+const desktopOutputDirInput = ref('')
+const desktopOutputDirPending = ref('')
 const desktopOutputDirLoading = ref(false)
+const desktopOutputDirApplying = ref(false)
 const desktopOutputDirError = ref('')
+const desktopOutputDirMessage = ref('')
+const desktopOutputDirIsDefault = ref(true)
+const desktopOutputDirCanChange = ref(true)
+const desktopOutputDirUnavailableReason = ref('')
 const desktopOutputDirText = computed(() => {
   if (!isDesktopEnv.value) return '仅桌面端可用'
   const v = String(desktopOutputDir.value || '').trim()
   return v || '—'
 })
+const desktopOutputDirDefaultText = computed(() => {
+  if (!isDesktopEnv.value) return '仅桌面端可用'
+  const v = String(desktopOutputDirDefault.value || '').trim()
+  return v || '—'
+})
+const desktopOutputDirPendingText = computed(() => {
+  const v = String(desktopOutputDirPending.value || '').trim()
+  return v || ''
+})
+const desktopOutputDirControlsDisabled = computed(() => (
+  !isDesktopEnv.value || !desktopOutputDirCanChange.value || desktopOutputDirLoading.value || desktopOutputDirApplying.value
+))
 
 const desktopLogFilePath = ref('')
 const desktopLogFileLoading = ref(false)
@@ -530,12 +605,33 @@ const refreshDesktopBackendPort = async () => {
 
 const refreshDesktopOutputDir = async () => {
   if (!process.client || typeof window === 'undefined') return
-  if (!window.wechatDesktop?.getOutputDir) return
+  if (!window.wechatDesktop?.getOutputDir && !window.wechatDesktop?.getOutputDirInfo) return
   desktopOutputDirLoading.value = true
   desktopOutputDirError.value = ''
   try {
+    if (window.wechatDesktop?.getOutputDirInfo) {
+      const info = await window.wechatDesktop.getOutputDirInfo()
+      desktopOutputDir.value = String(info?.path || '').trim()
+      desktopOutputDirDefault.value = String(info?.defaultPath || '').trim()
+      desktopOutputDirPending.value = String(info?.pendingPath || '').trim()
+      desktopOutputDirIsDefault.value = !!info?.isDefault
+      desktopOutputDirCanChange.value = info?.canChange !== false
+      desktopOutputDirUnavailableReason.value = String(info?.changeUnavailableReason || '').trim()
+      desktopOutputDirInput.value = desktopOutputDir.value || desktopOutputDirDefault.value
+      if (info?.lastError) {
+        desktopOutputDirError.value = String(info.lastError || '').trim()
+      }
+      return
+    }
+
     const v = await window.wechatDesktop.getOutputDir()
     desktopOutputDir.value = String(v || '').trim()
+    desktopOutputDirDefault.value = desktopOutputDir.value
+    desktopOutputDirPending.value = ''
+    desktopOutputDirIsDefault.value = true
+    desktopOutputDirCanChange.value = false
+    desktopOutputDirUnavailableReason.value = '当前桌面环境不支持修改 output 目录'
+    desktopOutputDirInput.value = desktopOutputDir.value
   } catch (e) {
     desktopOutputDirError.value = e?.message || '读取 output 目录失败'
   } finally {
@@ -558,6 +654,62 @@ const onDesktopOpenOutputDir = async () => {
   }
 }
 
+const onDesktopChooseOutputDir = async () => {
+  if (!process.client || typeof window === 'undefined') return
+  if (!window.wechatDesktop?.chooseDirectory) return
+  desktopOutputDirError.value = ''
+  desktopOutputDirMessage.value = ''
+  try {
+    const result = await window.wechatDesktop.chooseDirectory({ title: '选择新的 output 目录' })
+    if (result && !result.canceled && Array.isArray(result.filePaths) && result.filePaths.length > 0) {
+      desktopOutputDirInput.value = String(result.filePaths[0] || '').trim()
+    }
+  } catch (e) {
+    desktopOutputDirError.value = e?.message || '选择 output 目录失败'
+  }
+}
+
+const applyDesktopOutputDir = async (nextDir) => {
+  if (!process.client || typeof window === 'undefined') return
+  if (!window.wechatDesktop?.setOutputDir) {
+    desktopOutputDirError.value = '当前桌面环境不支持修改 output 目录'
+    return
+  }
+  if (!desktopOutputDirCanChange.value) {
+    desktopOutputDirError.value = desktopOutputDirUnavailableReason.value || '开发模式不支持界面修改 output 目录'
+    return
+  }
+  desktopOutputDirApplying.value = true
+  desktopOutputDirError.value = ''
+  desktopOutputDirMessage.value = ''
+  try {
+    const res = await window.wechatDesktop.setOutputDir(String(nextDir ?? '').trim())
+    if (res?.success === false) {
+      desktopOutputDirError.value = String(res?.error || '修改 output 目录失败').trim()
+      await refreshDesktopOutputDir()
+      return
+    }
+    await refreshDesktopOutputDir()
+    desktopOutputDirMessage.value = String(
+      res?.message || (res?.changed === false ? 'output 目录未变化' : 'output 目录已更新')
+    ).trim()
+  } catch (e) {
+    desktopOutputDirError.value = e?.message || '修改 output 目录失败'
+    await refreshDesktopOutputDir()
+  } finally {
+    desktopOutputDirApplying.value = false
+  }
+}
+
+const onDesktopOutputDirApply = async () => {
+  await applyDesktopOutputDir(desktopOutputDirInput.value)
+}
+
+const onDesktopOutputDirReset = async () => {
+  desktopOutputDirInput.value = desktopOutputDirDefault.value
+  await applyDesktopOutputDir('')
+}
+
 const refreshBackendLogFileInfo = async () => {
   if (!process.client || typeof window === 'undefined') return
   desktopLogFileLoading.value = true
@@ -702,6 +854,9 @@ const onDesktopCheckUpdates = async () => {
 watch(() => props.open, async (isOpen) => {
   if (!isOpen) return
   await refreshBackendLogFileInfo()
+  if (isDesktopEnv.value) {
+    await refreshDesktopOutputDir()
+  }
 }, { immediate: true })
 
 onMounted(async () => {

src/wechat_decrypt_tool/app_paths.py

@@ -3,6 +3,9 @@ from __future__ import annotations
 import os
 from pathlib import Path
 
+ENV_DATA_DIR_KEY = "WECHAT_TOOL_DATA_DIR"
+ENV_OUTPUT_DIR_KEY = "WECHAT_TOOL_OUTPUT_DIR"
+
 
 def get_data_dir() -> Path:
     """Base writable directory for all runtime output (logs, databases, key store).
@@ -12,13 +15,16 @@ def get_data_dir() -> Path:
     - Dev defaults to the current working directory (repo root).
     """
 
-    v = os.environ.get("WECHAT_TOOL_DATA_DIR", "").strip()
+    v = os.environ.get(ENV_DATA_DIR_KEY, "").strip()
     if v:
-        return Path(v)
+        return Path(v).expanduser()
     return Path.cwd()
 
 
 def get_output_dir() -> Path:
+    v = os.environ.get(ENV_OUTPUT_DIR_KEY, "").strip()
+    if v:
+        return Path(v).expanduser()
     return get_data_dir() / "output"
 
 
@@ -28,4 +34,3 @@ def get_output_databases_dir() -> Path:
 
 def get_account_keys_path() -> Path:
     return get_output_dir() / "account_keys.json"
-

tests/test_output_dir_override.py

@@ -0,0 +1,93 @@
+import importlib
+import logging
+import os
+import sys
+import unittest
+from pathlib import Path
+from tempfile import TemporaryDirectory
+
+
+ROOT = Path(__file__).resolve().parents[1]
+sys.path.insert(0, str(ROOT / "src"))
+
+
+def _close_logging_handlers() -> None:
+    for logger_name in ("", "uvicorn", "uvicorn.access", "uvicorn.error", "fastapi"):
+        lg = logging.getLogger(logger_name)
+        for handler in lg.handlers[:]:
+            try:
+                handler.close()
+            except Exception:
+                pass
+            try:
+                lg.removeHandler(handler)
+            except Exception:
+                pass
+
+
+class TestOutputDirOverride(unittest.TestCase):
+    def setUp(self) -> None:
+        self._prev_data_dir = os.environ.get("WECHAT_TOOL_DATA_DIR")
+        self._prev_output_dir = os.environ.get("WECHAT_TOOL_OUTPUT_DIR")
+        self._data_dir = TemporaryDirectory()
+        self._output_dir = TemporaryDirectory()
+        os.environ["WECHAT_TOOL_DATA_DIR"] = self._data_dir.name
+        os.environ["WECHAT_TOOL_OUTPUT_DIR"] = self._output_dir.name
+
+        import wechat_decrypt_tool.app_paths as app_paths
+        import wechat_decrypt_tool.key_store as key_store
+        import wechat_decrypt_tool.logging_config as logging_config
+        import wechat_decrypt_tool.runtime_settings as runtime_settings
+
+        importlib.reload(app_paths)
+        importlib.reload(logging_config)
+        importlib.reload(runtime_settings)
+        importlib.reload(key_store)
+
+        self.app_paths = app_paths
+        self.key_store = key_store
+        self.logging_config = logging_config
+        self.runtime_settings = runtime_settings
+
+    def tearDown(self) -> None:
+        _close_logging_handlers()
+        if self._prev_data_dir is None:
+            os.environ.pop("WECHAT_TOOL_DATA_DIR", None)
+        else:
+            os.environ["WECHAT_TOOL_DATA_DIR"] = self._prev_data_dir
+
+        if self._prev_output_dir is None:
+            os.environ.pop("WECHAT_TOOL_OUTPUT_DIR", None)
+        else:
+            os.environ["WECHAT_TOOL_OUTPUT_DIR"] = self._prev_output_dir
+
+        self._data_dir.cleanup()
+        self._output_dir.cleanup()
+
+    def test_app_paths_prefers_output_dir_override(self) -> None:
+        self.assertEqual(self.app_paths.get_output_dir(), Path(self._output_dir.name))
+        self.assertEqual(
+            self.app_paths.get_output_databases_dir(),
+            Path(self._output_dir.name) / "databases",
+        )
+
+    def test_logging_runtime_settings_and_key_store_use_output_override(self) -> None:
+        log_file = self.logging_config.setup_logging()
+        self.assertTrue(log_file.is_relative_to(Path(self._output_dir.name) / "logs"))
+
+        self.runtime_settings.write_backend_port_setting(12001)
+        runtime_settings_path = Path(self._output_dir.name) / "runtime_settings.json"
+        self.assertTrue(runtime_settings_path.exists())
+        self.assertEqual(self.runtime_settings.read_backend_port_setting(), 12001)
+
+        self.key_store.upsert_account_keys_in_store("wxid_test", db_key="abc123")
+        key_store_path = Path(self._output_dir.name) / "account_keys.json"
+        self.assertTrue(key_store_path.exists())
+        self.assertEqual(
+            self.key_store.get_account_keys_from_store("wxid_test").get("db_key"),
+            "abc123",
+        )
+
+
+if __name__ == "__main__":
+    unittest.main()