fix(auth,migration): sanitize legacy wallet name and preserve legacy flag during migration

PR_BODY.md

@@ -0,0 +1,19 @@
+Summary
+
+- Preserve `WalletConfig.isLegacyWallet` in `copy()` so legacy wallets route to `AuthRestoreRequested`.
+- Sanitize legacy wallet names: replace non-alphanumeric (Unicode letters/digits) except "_" with "_".
+- Resolve collisions by appending the lowest integer suffix (e.g., name, name_1, name_2, ...).
+- Apply during legacy migration in `AuthBloc._onRestore`; delete legacy entry after success.
+
+Why
+
+Fixes a critical bug where some users can't log into wallets created with old versions and the wallet disappears.
+
+Testing
+
+- Create a legacy wallet with special characters and attempt login; verify migration uses sanitized unique name and signs in.
+- Verify if a non-legacy wallet already has the sanitized name, the migrated wallet uses the lowest available _N suffix.
+
+Notes
+
+No API changes. Static analysis passes for changed files.

lib/bloc/auth_bloc/auth_bloc.dart

@@ -239,12 +239,46 @@ class AuthBloc extends Bloc<AuthBlocEvent, AuthBlocState> with TrezorAuthMixin {
     Emitter<AuthBlocState> emit,
   ) async {
     try {
-      if (await _didSignInExistingWallet(event.wallet, event.password)) {
+      // Legacy wallets: sanitize base name, try sign-in, then resolve
+      // uniqueness only if needed. Non-legacy restores (seed imports) keep the
+      // user-provided name unchanged.
+      Wallet workingWallet = event.wallet;
+      if (event.wallet.isLegacyWallet) {
+        final String baseName = _walletsRepository.sanitizeLegacyMigrationName(
+          event.wallet.name,
+        );
+        final Wallet sanitizedBaseWallet = event.wallet.copyWith(
+          name: baseName,
+        );
+
+        // Attempt sign-in with sanitized base name first to avoid creating a
+        // suffixed duplicate when a migrated wallet already exists.
+        if (await _didSignInExistingWallet(
+          sanitizedBaseWallet,
+          event.password,
+        )) {
+          add(
+            AuthSignInRequested(
+              wallet: sanitizedBaseWallet,
+              password: event.password,
+            ),
+          );
+          _log.warning('Wallet $baseName already exists, attempting sign-in');
+          return;
+        }
+
+        // Otherwise, resolve the lowest available unique name for registration.
+        final String uniqueName = await _walletsRepository
+            .resolveUniqueWalletName(baseName);
+        workingWallet = event.wallet.copyWith(name: uniqueName);
+      }
+
+      if (await _didSignInExistingWallet(workingWallet, event.password)) {
         add(
-          AuthSignInRequested(wallet: event.wallet, password: event.password),
+          AuthSignInRequested(wallet: workingWallet, password: event.password),
         );
         _log.warning(
-          'Wallet ${event.wallet.name} already exists, attempting sign-in',
+          'Wallet ${workingWallet.name} already exists, attempting sign-in',
         );
         return;
       }
@@ -254,10 +288,10 @@ class AuthBloc extends Bloc<AuthBlocEvent, AuthBlocState> with TrezorAuthMixin {
       final weakPasswordsAllowed = await _areWeakPasswordsAllowed();
       await _kdfSdk.auth.register(
         password: event.password,
-        walletName: event.wallet.name,
+        walletName: workingWallet.name,
         mnemonic: Mnemonic.plaintext(event.seed),
         options: AuthOptions(
-          derivationMethod: event.wallet.config.type == WalletType.hdwallet
+          derivationMethod: workingWallet.config.type == WalletType.hdwallet
               ? DerivationMethod.hdWallet
               : DerivationMethod.iguana,
           allowWeakPassword: weakPasswordsAllowed,
@@ -268,16 +302,18 @@ class AuthBloc extends Bloc<AuthBlocEvent, AuthBlocState> with TrezorAuthMixin {
         'Successfully restored wallet from a seed. '
         'Setting up wallet metadata and logging in...',
       );
-      await _kdfSdk.setWalletType(event.wallet.config.type);
-      await _kdfSdk.confirmSeedBackup(hasBackup: event.wallet.config.hasBackup);
+      await _kdfSdk.setWalletType(workingWallet.config.type);
+      await _kdfSdk.confirmSeedBackup(
+        hasBackup: workingWallet.config.hasBackup,
+      );
       // Filter out geo-blocked assets from default coins before adding to wallet
       final allowedDefaultCoins = _filterBlockedAssets(enabledByDefaultCoins);
       await _kdfSdk.addActivatedCoins(allowedDefaultCoins);
-      if (event.wallet.config.activatedCoins.isNotEmpty) {
+      if (workingWallet.config.activatedCoins.isNotEmpty) {
         // Seed import files and legacy wallets may contain removed or unsupported
         // coins, so we filter them out before adding them to the wallet metadata.
         final availableWalletCoins = _filterOutUnsupportedCoins(
-          event.wallet.config.activatedCoins,
+          workingWallet.config.activatedCoins,
         );
         // Also filter out geo-blocked assets from restored wallet coins
         final allowedWalletCoins = _filterBlockedAssets(availableWalletCoins);
@@ -289,7 +325,7 @@ class AuthBloc extends Bloc<AuthBlocEvent, AuthBlocState> with TrezorAuthMixin {
       if (event.wallet.isLegacyWallet) {
         _log.info(
           'Migration successful. '
-          'Deleting legacy wallet ${event.wallet.name}',
+          'Deleting legacy wallet ${workingWallet.name}',
         );
         await _walletsRepository.deleteWallet(
           event.wallet,

lib/blocs/wallets_repository.dart

@@ -220,4 +220,38 @@ class WalletsRepository {
       }
     }
   }
+
+  /// Sanitizes a legacy wallet name for migration by replacing any
+  /// non-alphanumeric character (Unicode letters/digits) except underscore
+  /// with an underscore. This ensures compatibility with stricter name rules
+  /// in the target storage/backend.
+  String sanitizeLegacyMigrationName(String name) {
+    final sanitized = name.replaceAll(
+      RegExp(r'[^\p{L}\p{N}_]', unicode: true),
+      '_',
+    );
+    // Avoid returning an empty string
+    return sanitized.isEmpty ? '_' : sanitized;
+  }
+
+  /// Resolves a unique wallet name by appending the lowest integer suffix
+  /// starting at 1 that makes the name unique across both SDK and legacy
+  /// wallets. If [baseName] is already unique, it is returned unchanged.
+  Future<String> resolveUniqueWalletName(String baseName) async {
+    final List<Wallet> allWallets = await getWallets();
+    final Set<String> existing = allWallets.map((w) => w.name).toSet();
+    if (!existing.contains(baseName)) return baseName;
+
+    int i = 1;
+    while (existing.contains('${baseName}_$i')) {
+      i++;
+    }
+    return '${baseName}_$i';
+  }
+
+  /// Convenience helper for migration: sanitize and then ensure uniqueness.
+  Future<String> sanitizeAndResolveLegacyWalletName(String legacyName) async {
+    final sanitized = sanitizeLegacyMigrationName(legacyName);
+    return resolveUniqueWalletName(sanitized);
+  }
 }

lib/model/wallet.dart

@@ -67,12 +67,8 @@ class Wallet {
   Wallet copy() {
     return Wallet(id: id, name: name, config: config.copy());
   }
-
-  Wallet copyWith({
-    String? id,
-    String? name,
-    WalletConfig? config,
-  }) {
+
+  Wallet copyWith({String? id, String? name, WalletConfig? config}) {
     return Wallet(
       id: id ?? this.id,
       name: name ?? this.name,
@@ -129,9 +125,12 @@ class WalletConfig {
       type: type,
       seedPhrase: seedPhrase,
       pubKey: pubKey,
+      // Preserve legacy flag when copying config; losing this flag breaks
+      // legacy login flow and can hide the wallet from lists.
+      isLegacyWallet: isLegacyWallet,
     );
   }
-  
+
   WalletConfig copyWith({
     String? seedPhrase,
     String? pubKey,

pubspec.yaml

@@ -15,7 +15,7 @@ publish_to: "none" # Remove this line if you wish to publish to pub.dev
 # In iOS, build-name is used as CFBundleShortVersionString while build-number used as CFBundleVersion.
 # Read more about iOS versioning at
 # https://developer.apple.com/library/archive/documentation/General/Reference/InfoPlistKeyReference/Articles/CoreFoundationKeys.html
-version: 0.9.3+0
+version: 0.9.3+1
 
 environment:
   sdk: ">=3.8.1 <4.0.0"