refactor: FilterMap extension

lib/src/model/events/room_encrypted_content.dart

@@ -23,6 +23,7 @@
 
 import 'package:matrix_api_lite/src/utils/logs.dart';
 
+import '../../utils/filter_map_extension.dart';
 import '../../utils/try_get_map_extension.dart';
 import '../basic_event.dart';
 
@@ -31,11 +32,6 @@ extension RoomEncryptedContentBasicEventExtension on BasicEvent {
       RoomEncryptedContent.fromJson(content);
 }
 
-/// Convert Nullable iterable of MapEntries to Map
-extension ToMap<T1, T2> on Iterable<MapEntry<T1, T2>> {
-  Map<T1, T2> toMap() => Map.fromEntries(this);
-}
-
 class RoomEncryptedContent {
   String algorithm;
   String senderKey;
@@ -53,16 +49,7 @@ class RoomEncryptedContent {
         // filter out invalid/incomplete CiphertextInfos
         ciphertextOlm = json
             .tryGet<Map<String, dynamic>>('ciphertext', TryGet.silent)
-            ?.entries
-            .map((e) {
-              try {
-                return MapEntry(e.key, CiphertextInfo.fromJson(e.value));
-              } catch (_) {
-                return null;
-              }
-            })
-            .whereType<MapEntry<String, CiphertextInfo>>()
-            .toMap();
+            ?.catchMap((k, v) => MapEntry(k, CiphertextInfo.fromJson(v)));
 
   Map<String, dynamic> toJson() {
     final data = <String, dynamic>{};

lib/src/utils/filter_map_extension.dart

@@ -0,0 +1,14 @@
+extension FilterMap<K, V> on Map<K, V> {
+  Map<K2, V2> filterMap<K2, V2>(MapEntry<K2, V2>? Function(K, V) f) =>
+      Map.fromEntries(
+          entries.map((e) => f(e.key, e.value)).whereType<MapEntry<K2, V2>>());
+
+  Map<K2, V2> catchMap<K2, V2>(MapEntry<K2, V2> Function(K, V) f) =>
+      filterMap((k, v) {
+        try {
+          return f(k, v);
+        } catch (_) {
+          return null;
+        }
+      });
+}