fix(imap): handle mailbox names containing parentheses

lib/src/imap/imap_client.dart

@@ -1302,7 +1302,13 @@ class ImapClient extends ClientBase {
     }
     final pathSeparator = serverInfo.pathSeparator ?? '/';
     var encodedPath = Mailbox.encode(path, pathSeparator);
+    // RFC 3501: '(' ')' '{' are atom-specials and may not appear in an
+    // unquoted atom, so a mailbox such as "Audit(s)" has to be quoted or
+    // the server rejects the command with "BAD Invalid characters in atom".
     if (encodedPath.contains(' ') ||
+        encodedPath.contains('(') ||
+        encodedPath.contains(')') ||
+        encodedPath.contains('{') ||
         (alwaysQuote && !encodedPath.startsWith('"'))) {
       encodedPath = '"$encodedPath"';
     }

lib/src/private/imap/list_parser.dart

@@ -81,9 +81,14 @@ class ListParser extends ResponseParser<List<Mailbox>> {
     // Parses extended data
     final boxExtendedData = <String, List<String>>{};
     if (isExtended) {
-      final extraInfoStartIndex = listDetails.indexOf('(');
+      // Only a '(' outside a double-quoted string opens the extended data.
+      // Mailbox names may contain parentheses (e.g. "INBOX.Audit(s)") and
+      // those must not be mistaken for the extended-data delimiter.
+      final extraInfoStartIndex = _firstUnquotedOpenParen(listDetails);
       final extraInfoEndIndex = listDetails.lastIndexOf(')');
-      if (extraInfoEndIndex != -1 && extraInfoStartIndex < extraInfoEndIndex) {
+      if (extraInfoStartIndex != -1 &&
+          extraInfoEndIndex != -1 &&
+          extraInfoStartIndex < extraInfoEndIndex) {
         final extraInfo = listDetails.substring(
           extraInfoStartIndex + 1,
           extraInfoEndIndex,
@@ -143,6 +148,21 @@ class ListParser extends ResponseParser<List<Mailbox>> {
     boxes.add(box);
   }
 
+  /// Returns the index of the first '(' that is not inside a double-quoted
+  /// string, or -1 if there is none.
+  static int _firstUnquotedOpenParen(String s) {
+    var inQuote = false;
+    for (var i = 0; i < s.length; i++) {
+      if (s[i] == '"') {
+        inQuote = !inQuote;
+      } else if (s[i] == '(' && !inQuote) {
+        return i;
+      }
+    }
+
+    return -1;
+  }
+
   void _addFlags(
     int flagsStartIndex,
     int flagsEndIndex,

test/imap/imap_client_test.dart

@@ -220,6 +220,53 @@ void main() {
     );
   });
 
+  test('ImapClient listMailboxes via LIST-STATUS preserves parentheses in '
+      'mailbox names', () async {
+    // Regression: with isExtended=true (LIST-STATUS return options), the
+    // extended-data parser did listDetails.indexOf('(') which found the '('
+    // inside "INBOX.Financial.Audit(s)" and treated 's)' as extended data.
+    // The path was truncated (removing the closing '"' too), so the
+    // subsequent quote-strip ate the 'i', leaving name='Aud' and a path
+    // that did not exist on the server.
+    mockServer.response =
+        '* LIST (\\HasChildren \\UnMarked) "." "INBOX.Financial.Audit(s)"\r\n'
+        '* STATUS "INBOX.Financial.Audit(s)" (MESSAGES 0 UNSEEN 0)\r\n'
+        '* LIST (\\HasNoChildren \\UnMarked) "." "INBOX.Financial.Home Hardware"\r\n'
+        '* STATUS "INBOX.Financial.Home Hardware" (MESSAGES 40 UNSEEN 0)\r\n'
+        '<tag> OK List completed (0.001 + 0.000 secs).';
+    final listResponse = await client.listMailboxes(
+      path: '"INBOX.Financial."',
+      recursive: false,
+      returnOptions: [
+        ReturnOption.status(['MESSAGES', 'UNSEEN']),
+        ReturnOption.children(),
+      ],
+    );
+    expect(listResponse, hasLength(2));
+
+    final audit = listResponse[0];
+    expect(
+      audit.name,
+      equals('Audit(s)'),
+      reason: 'name was truncated at "(" inside mailbox name',
+    );
+    expect(
+      audit.path,
+      equals('INBOX.Financial.Audit(s)'),
+      reason: 'path was truncated at "(" inside mailbox name',
+    );
+    expect(audit.hasChildren, isTrue);
+
+    final homeHardware = listResponse[1];
+    expect(
+      homeHardware.name,
+      equals('Home Hardware'),
+      reason: 'quoted name with space should be preserved',
+    );
+    expect(homeHardware.path, equals('INBOX.Financial.Home Hardware'));
+    expect(homeHardware.messagesExists, equals(40));
+  });
+
   test('ImapClient LSUB', () async {
     mockServer.response =
         '* LSUB (\\HasChildren \\Marked) "/" INBOX\r\n'
@@ -1172,6 +1219,24 @@ void main() {
     );
   });
 
+  test('ImapClient copy quotes a target path containing parentheses', () async {
+    // '(' and ')' are atom-specials (RFC 3501 section 9), so an unquoted
+    // `COPY 1:3 INBOX.Financial.Audit(s)` is rejected by servers with
+    // "BAD Invalid characters in atom". _encodeMailboxPath used to quote a
+    // path only when it contained a space.
+    await _selectInbox();
+    mockServer.response = '<tag> OK messages copied';
+    await client.copy(
+      MessageSequence.fromRange(1, 3),
+      targetMailboxPath: 'INBOX.Financial.Audit(s)',
+    );
+
+    expect(
+      mockServer.requests.last,
+      contains(' COPY 1:3 "INBOX.Financial.Audit(s)"'),
+    );
+  });
+
   test('ImapClient uid copy', () async {
     await _selectInbox();
     mockServer.response =

test/imap/mock_imap_server.dart

@@ -21,8 +21,13 @@ class MockImapServer {
   String? response;
   String? _overrideTag;
 
+  /// Everything the client has sent, one entry per received chunk, so tests
+  /// can assert on the command text actually written to the socket.
+  final requests = <String>[];
+
   void parseRequest(Uint8List data) {
     final line = String.fromCharCodes(data);
+    requests.add(line);
     // print('C: $line');
     final firstSpaceIndex = line.indexOf(' ');
     String? tag = firstSpaceIndex == -1