fix(cliproxy): make backend switching work with version pins and status

- Add backend param to isCLIProxyInstalled(), getCLIProxyPath(),
  getInstalledCliproxyVersion(), installCliproxyVersion()
- Update getBinaryStatus() to pass backend to all helper functions
- Add getBackendLabel() helper for dynamic CLI messages
- Replace hardcoded "CLIProxy Plus" strings with dynamic labels
- Pass --backend flag through install/update command handlers
- Import CLIProxyBackend type from types.ts instead of redefining

Setting `cliproxy.backend: original` in config.yaml now correctly
uses the original backend for version pins and binary operations.

src/cliproxy/binary-manager.ts

@@ -26,9 +26,10 @@ import {
   getVersionPinPath,
   readInstalledVersion,
   ensureBinary,
+  migrateVersionPin,
 } from './binary';
 
-type CLIProxyBackend = 'original' | 'plus';
+import type { CLIProxyBackend } from './types';
 
 /**
  * Get backend from config or default to 'plus'
@@ -111,7 +112,11 @@ export class BinaryManager {
 /** Convenience function respecting version pin */
 export async function ensureCLIProxyBinary(verbose = false): Promise<string> {
   const backend = getConfiguredBackend();
-  const pinnedVersion = getPinnedVersion();
+
+  // Migrate old shared pin to backend-specific location (one-time migration)
+  migrateVersionPin(backend);
+
+  const pinnedVersion = getPinnedVersion(backend);
   if (pinnedVersion) {
     if (verbose) console.error(`[cliproxy] Using pinned version: ${pinnedVersion}`);
     return new BinaryManager(
@@ -127,27 +132,34 @@ export async function ensureCLIProxyBinary(verbose = false): Promise<string> {
 }
 
 /** Check if CLIProxyAPI binary is installed */
-export function isCLIProxyInstalled(): boolean {
-  const backend = getConfiguredBackend();
-  return new BinaryManager({}, backend).isBinaryInstalled();
+export function isCLIProxyInstalled(backend?: CLIProxyBackend): boolean {
+  const effectiveBackend = backend ?? getConfiguredBackend();
+  return new BinaryManager({}, effectiveBackend).isBinaryInstalled();
 }
 
 /** Get CLIProxyAPI binary path (may not exist) */
-export function getCLIProxyPath(): string {
-  const backend = getConfiguredBackend();
-  return new BinaryManager({}, backend).getBinaryPath();
+export function getCLIProxyPath(backend?: CLIProxyBackend): string {
+  const effectiveBackend = backend ?? getConfiguredBackend();
+  return new BinaryManager({}, effectiveBackend).getBinaryPath();
 }
 
 /** Get installed CLIProxyAPI version from .version file */
-export function getInstalledCliproxyVersion(): string {
-  const backend = getConfiguredBackend();
-  return readInstalledVersion(getBackendBinDir(backend), BACKEND_CONFIG[backend].fallbackVersion);
+export function getInstalledCliproxyVersion(backend?: CLIProxyBackend): string {
+  const effectiveBackend = backend ?? getConfiguredBackend();
+  return readInstalledVersion(
+    getBackendBinDir(effectiveBackend),
+    BACKEND_CONFIG[effectiveBackend].fallbackVersion
+  );
 }
 
 /** Install a specific version of CLIProxyAPI */
-export async function installCliproxyVersion(version: string, verbose = false): Promise<void> {
-  const backend = getConfiguredBackend();
-  const manager = new BinaryManager({ version, verbose, forceVersion: true }, backend);
+export async function installCliproxyVersion(
+  version: string,
+  verbose = false,
+  backend?: CLIProxyBackend
+): Promise<void> {
+  const effectiveBackend = backend ?? getConfiguredBackend();
+  const manager = new BinaryManager({ version, verbose, forceVersion: true }, effectiveBackend);
 
   // Check if proxy is running and stop it first
   if (isProxyRunning()) {
@@ -165,8 +177,11 @@ export async function installCliproxyVersion(version: string, verbose = false):
   }
 
   if (manager.isBinaryInstalled()) {
+    const label = effectiveBackend === 'plus' ? 'CLIProxy Plus' : 'CLIProxy';
     if (verbose)
-      console.log(info(`Removing existing CLIProxy Plus v${getInstalledCliproxyVersion()}`));
+      console.log(
+        info(`Removing existing ${label} v${getInstalledCliproxyVersion(effectiveBackend)}`)
+      );
     manager.deleteBinary();
   }
   await manager.ensureBinary();
@@ -223,6 +238,7 @@ export {
   savePinnedVersion,
   clearPinnedVersion,
   isVersionPinned,
+  migrateVersionPin,
 };
 
 export default BinaryManager;

src/cliproxy/binary/index.ts

@@ -25,6 +25,7 @@ export {
   savePinnedVersion,
   clearPinnedVersion,
   isVersionPinned,
+  migrateVersionPin,
 } from './version-cache';
 
 // Version Checker

src/cliproxy/binary/version-cache.ts

@@ -12,6 +12,8 @@ import {
   VERSION_PIN_FILE,
   VersionListCache,
 } from './types';
+import { DEFAULT_BACKEND } from '../platform-detector';
+import type { CLIProxyBackend } from '../types';
 
 /**
  * Get path to version cache file
@@ -21,10 +23,10 @@ export function getVersionCachePath(): string {
 }
 
 /**
- * Get path to version pin file
+ * Get path to version pin file (backend-specific)
  */
-export function getVersionPinPath(): string {
-  return path.join(getBinDir(), VERSION_PIN_FILE);
+export function getVersionPinPath(backend: CLIProxyBackend = DEFAULT_BACKEND): string {
+  return path.join(getBinDir(), backend, VERSION_PIN_FILE);
 }
 
 /**
@@ -98,10 +100,10 @@ export function writeInstalledVersion(binPath: string, version: string): void {
 }
 
 /**
- * Get pinned version if one exists
+ * Get pinned version if one exists (backend-specific)
  */
-export function getPinnedVersion(): string | null {
-  const pinPath = getVersionPinPath();
+export function getPinnedVersion(backend: CLIProxyBackend = DEFAULT_BACKEND): string | null {
+  const pinPath = getVersionPinPath(backend);
   if (!fs.existsSync(pinPath)) {
     return null;
   }
@@ -113,10 +115,13 @@ export function getPinnedVersion(): string | null {
 }
 
 /**
- * Save pinned version to persist user's explicit choice
+ * Save pinned version to persist user's explicit choice (backend-specific)
  */
-export function savePinnedVersion(version: string): void {
-  const pinPath = getVersionPinPath();
+export function savePinnedVersion(
+  version: string,
+  backend: CLIProxyBackend = DEFAULT_BACKEND
+): void {
+  const pinPath = getVersionPinPath(backend);
   try {
     fs.mkdirSync(path.dirname(pinPath), { recursive: true });
     fs.writeFileSync(pinPath, version, 'utf8');
@@ -126,10 +131,10 @@ export function savePinnedVersion(version: string): void {
 }
 
 /**
- * Clear pinned version (unpin)
+ * Clear pinned version (unpin) - backend-specific
  */
-export function clearPinnedVersion(): void {
-  const pinPath = getVersionPinPath();
+export function clearPinnedVersion(backend: CLIProxyBackend = DEFAULT_BACKEND): void {
+  const pinPath = getVersionPinPath(backend);
   if (fs.existsSync(pinPath)) {
     try {
       fs.unlinkSync(pinPath);
@@ -140,10 +145,32 @@ export function clearPinnedVersion(): void {
 }
 
 /**
- * Check if a version is currently pinned
+ * Check if a version is currently pinned (backend-specific)
  */
-export function isVersionPinned(): boolean {
-  return getPinnedVersion() !== null;
+export function isVersionPinned(backend: CLIProxyBackend = DEFAULT_BACKEND): boolean {
+  return getPinnedVersion(backend) !== null;
+}
+
+/**
+ * Migrate old shared version pin to backend-specific location.
+ * Called once on first run after update.
+ */
+export function migrateVersionPin(backend: CLIProxyBackend): void {
+  const oldPinPath = path.join(getBinDir(), VERSION_PIN_FILE);
+  if (!fs.existsSync(oldPinPath)) return;
+
+  try {
+    const oldVersion = fs.readFileSync(oldPinPath, 'utf8').trim();
+    if (!oldVersion) return;
+
+    // Save to new backend-specific location
+    savePinnedVersion(oldVersion, backend);
+
+    // Delete old shared file
+    fs.unlinkSync(oldPinPath);
+  } catch {
+    // Silent fail - not critical
+  }
 }
 
 // ==================== Version List Cache ====================

src/cliproxy/services/binary-service.ts

@@ -58,10 +58,10 @@ export function getBinaryStatus(backend?: CLIProxyBackend): BinaryStatusResult {
     backend ?? loadOrCreateUnifiedConfig().cliproxy?.backend ?? DEFAULT_BACKEND;
   const backendConfig = BACKEND_CONFIG[effectiveBackend];
   return {
-    installed: isCLIProxyInstalled(),
-    currentVersion: getInstalledCliproxyVersion(),
-    pinnedVersion: getPinnedVersion(),
-    binaryPath: getCLIProxyPath(),
+    installed: isCLIProxyInstalled(effectiveBackend),
+    currentVersion: getInstalledCliproxyVersion(effectiveBackend),
+    pinnedVersion: getPinnedVersion(effectiveBackend),
+    binaryPath: getCLIProxyPath(effectiveBackend),
     fallbackVersion: backendConfig.fallbackVersion,
     backend: effectiveBackend,
   };
@@ -100,7 +100,11 @@ export function isValidVersionFormat(version: string): boolean {
 /**
  * Install a specific version and pin it
  */
-export async function installVersion(version: string, verbose = false): Promise<InstallResult> {
+export async function installVersion(
+  version: string,
+  verbose = false,
+  backend?: CLIProxyBackend
+): Promise<InstallResult> {
   if (!isValidVersionFormat(version)) {
     return {
       success: false,
@@ -109,9 +113,12 @@ export async function installVersion(version: string, verbose = false): Promise<
     };
   }
 
+  const effectiveBackend =
+    backend ?? loadOrCreateUnifiedConfig().cliproxy?.backend ?? DEFAULT_BACKEND;
+
   try {
-    await installCliproxyVersion(version, verbose);
-    savePinnedVersion(version);
+    await installCliproxyVersion(version, verbose, effectiveBackend);
+    savePinnedVersion(version, effectiveBackend);
 
     return {
       success: true,
@@ -130,13 +137,19 @@ export async function installVersion(version: string, verbose = false): Promise<
 /**
  * Install latest version and clear any pin
  */
-export async function installLatest(verbose = false): Promise<InstallResult> {
+export async function installLatest(
+  verbose = false,
+  backend?: CLIProxyBackend
+): Promise<InstallResult> {
+  const effectiveBackend =
+    backend ?? loadOrCreateUnifiedConfig().cliproxy?.backend ?? DEFAULT_BACKEND;
+
   try {
     const latestVersion = await fetchLatestCliproxyVersion();
-    const currentVersion = getInstalledCliproxyVersion();
-    const wasPinned = isVersionPinned();
+    const currentVersion = getInstalledCliproxyVersion(effectiveBackend);
+    const wasPinned = isVersionPinned(effectiveBackend);
 
-    if (isCLIProxyInstalled() && latestVersion === currentVersion && !wasPinned) {
+    if (isCLIProxyInstalled(effectiveBackend) && latestVersion === currentVersion && !wasPinned) {
       return {
         success: true,
         version: latestVersion,
@@ -144,8 +157,8 @@ export async function installLatest(verbose = false): Promise<InstallResult> {
       };
     }
 
-    await installCliproxyVersion(latestVersion, verbose);
-    clearPinnedVersion();
+    await installCliproxyVersion(latestVersion, verbose, effectiveBackend);
+    clearPinnedVersion(effectiveBackend);
 
     return {
       success: true,

src/commands/cliproxy-command.ts

@@ -111,6 +111,13 @@ function getEffectiveBackend(cliBackend?: CLIProxyBackend): CLIProxyBackend {
   return config.cliproxy?.backend ?? DEFAULT_BACKEND;
 }
 
+/**
+ * Get display label for backend
+ */
+function getBackendLabel(backend: CLIProxyBackend): string {
+  return backend === 'plus' ? 'CLIProxy Plus' : 'CLIProxy';
+}
+
 interface CliproxyProfileArgs {
   name?: string;
   provider?: CLIProxyProfileName;
@@ -152,8 +159,10 @@ function formatModelOption(model: ModelEntry): string {
 
 async function handleCreate(args: string[]): Promise<void> {
   await initUI();
+  const { backend } = parseBackendArg(args);
+  const effectiveBackend = getEffectiveBackend(backend);
   const parsedArgs = parseProfileArgs(args);
-  console.log(header('Create CLIProxy Plus Variant'));
+  console.log(header(`Create ${getBackendLabel(effectiveBackend)} Variant`));
   console.log('');
 
   // Step 1: Profile name
@@ -292,7 +301,7 @@ async function handleCreate(args: string[]): Promise<void> {
 
   // Create variant
   console.log('');
-  console.log(info('Creating CLIProxy Plus variant...'));
+  console.log(info(`Creating ${getBackendLabel(effectiveBackend)} variant...`));
   const result = createVariant(name, provider, model, account);
 
   if (!result.success) {
@@ -530,14 +539,19 @@ async function showStatus(verbose: boolean, backend: CLIProxyBackend): Promise<v
   console.log('');
 }
 
-async function handleInstallVersion(version: string, verbose: boolean): Promise<void> {
-  console.log(info(`Installing CLIProxy Plus v${version}...`));
+async function handleInstallVersion(
+  version: string,
+  verbose: boolean,
+  backend: CLIProxyBackend
+): Promise<void> {
+  const label = getBackendLabel(backend);
+  console.log(info(`Installing ${label} v${version}...`));
   console.log('');
 
-  const result = await installVersion(version, verbose);
+  const result = await installVersion(version, verbose, backend);
   if (!result.success) {
     console.error('');
-    console.error(fail(`Failed to install CLIProxy Plus v${version}`));
+    console.error(fail(`Failed to install ${label} v${version}`));
     console.error(`    ${result.error}`);
     console.error('');
     console.error('Possible causes:');
@@ -546,12 +560,12 @@ async function handleInstallVersion(version: string, verbose: boolean): Promise<
     console.error('  3. GitHub API rate limiting');
     console.error('');
     console.error('Check available versions at:');
-    console.error('  https://github.com/router-for-me/CLIProxyAPIPlus/releases');
+    console.error(`  https://github.com/${BACKEND_CONFIG[backend].repo}/releases`);
     process.exit(1);
   }
 
   console.log('');
-  console.log(ok(`CLIProxy Plus v${version} installed (pinned)`));
+  console.log(ok(`${label} v${version} installed (pinned)`));
   console.log('');
   console.log(dim('This version will be used until you run:'));
   console.log(
@@ -560,10 +574,11 @@ async function handleInstallVersion(version: string, verbose: boolean): Promise<
   console.log('');
 }
 
-async function handleInstallLatest(verbose: boolean): Promise<void> {
-  console.log(info('Fetching latest CLIProxy Plus version...'));
+async function handleInstallLatest(verbose: boolean, backend: CLIProxyBackend): Promise<void> {
+  const label = getBackendLabel(backend);
+  console.log(info(`Fetching latest ${label} version...`));
 
-  const result = await installLatest(verbose);
+  const result = await installLatest(verbose, backend);
   if (!result.success) {
     console.error(fail(`Failed to install latest version: ${result.error}`));
     process.exit(1);
@@ -575,7 +590,7 @@ async function handleInstallLatest(verbose: boolean): Promise<void> {
   }
 
   console.log('');
-  console.log(ok(`CLIProxy Plus updated to v${result.version}`));
+  console.log(ok(`${label} updated to v${result.version}`));
   console.log(dim('Auto-update is now enabled.'));
   console.log('');
 }
@@ -1036,12 +1051,12 @@ export async function handleCliproxyCommand(args: string[]): Promise<void> {
     }
     // Strip leading 'v' prefix and whitespace (user may type " v6.6.80-0 ")
     version = version.trim().replace(/^v/, '');
-    await handleInstallVersion(version, verbose);
+    await handleInstallVersion(version, verbose, effectiveBackend);
     return;
   }
 
   if (remainingArgs.includes('--latest') || remainingArgs.includes('--update')) {
-    await handleInstallLatest(verbose);
+    await handleInstallLatest(verbose, effectiveBackend);
     return;
   }