feat: Implement parsing and sending of retractions

packages/moxxmpp/lib/moxxmpp.dart

@@ -73,6 +73,7 @@ export 'package:moxxmpp/src/xeps/xep_0384/types.dart';
 export 'package:moxxmpp/src/xeps/xep_0384/xep_0384.dart';
 export 'package:moxxmpp/src/xeps/xep_0385.dart';
 export 'package:moxxmpp/src/xeps/xep_0414.dart';
+export 'package:moxxmpp/src/xeps/xep_0424.dart';
 export 'package:moxxmpp/src/xeps/xep_0446.dart';
 export 'package:moxxmpp/src/xeps/xep_0447.dart';
 export 'package:moxxmpp/src/xeps/xep_0448.dart';

packages/moxxmpp/lib/src/events.dart

@@ -8,6 +8,7 @@ import 'package:moxxmpp/src/xeps/xep_0066.dart';
 import 'package:moxxmpp/src/xeps/xep_0085.dart';
 import 'package:moxxmpp/src/xeps/xep_0359.dart';
 import 'package:moxxmpp/src/xeps/xep_0385.dart';
+import 'package:moxxmpp/src/xeps/xep_0424.dart';
 import 'package:moxxmpp/src/xeps/xep_0446.dart';
 import 'package:moxxmpp/src/xeps/xep_0447.dart';
 import 'package:moxxmpp/src/xeps/xep_0461.dart';
@@ -71,6 +72,7 @@ class MessageEvent extends XmppEvent {
     this.fun,
     this.funReplacement,
     this.funCancellation,
+    this.messageRetraction,
   });
   final String body;
   final JID fromJid;
@@ -90,6 +92,7 @@ class MessageEvent extends XmppEvent {
   final String? funReplacement;
   final String? funCancellation;
   final bool encrypted;
+  final MessageRetractionData? messageRetraction;
   final Map<String, dynamic> other;
 }
 

packages/moxxmpp/lib/src/managers/data.dart

@@ -6,6 +6,7 @@ import 'package:moxxmpp/src/xeps/xep_0203.dart';
 import 'package:moxxmpp/src/xeps/xep_0359.dart';
 import 'package:moxxmpp/src/xeps/xep_0380.dart';
 import 'package:moxxmpp/src/xeps/xep_0385.dart';
+import 'package:moxxmpp/src/xeps/xep_0424.dart';
 import 'package:moxxmpp/src/xeps/xep_0446.dart';
 import 'package:moxxmpp/src/xeps/xep_0447.dart';
 import 'package:moxxmpp/src/xeps/xep_0461.dart';
@@ -55,6 +56,9 @@ class StanzaHandlerData with _$StanzaHandlerData {
       // This is for stanza handlers that are not part of the XMPP library but still need
       // pass data around.
       @Default(<String, dynamic>{}) Map<String, dynamic> other,
+      // If non-null, then it indicates the origin Id of the message that should be
+      // retracted
+      MessageRetractionData? messageRetraction,
     }
   ) = _StanzaHandlerData;
 }

packages/moxxmpp/lib/src/managers/data.freezed.dart

@@ -54,7 +54,11 @@ mixin _$StanzaHandlerData {
   DelayedDelivery? get delayedDelivery =>
       throw _privateConstructorUsedError; // This is for stanza handlers that are not part of the XMPP library but still need
 // pass data around.
-  Map<String, dynamic> get other => throw _privateConstructorUsedError;
+  Map<String, dynamic> get other =>
+      throw _privateConstructorUsedError; // If non-null, then it indicates the origin Id of the message that should be
+// retracted
+  MessageRetractionData? get messageRetraction =>
+      throw _privateConstructorUsedError;
 
   @JsonKey(ignore: true)
   $StanzaHandlerDataCopyWith<StanzaHandlerData> get copyWith =>
@@ -87,7 +91,8 @@ abstract class $StanzaHandlerDataCopyWith<$Res> {
       bool encrypted,
       ExplicitEncryptionType? encryptionType,
       DelayedDelivery? delayedDelivery,
-      Map<String, dynamic> other});
+      Map<String, dynamic> other,
+      MessageRetractionData? messageRetraction});
 }
 
 /// @nodoc
@@ -122,6 +127,7 @@ class _$StanzaHandlerDataCopyWithImpl<$Res>
     Object? encryptionType = freezed,
     Object? delayedDelivery = freezed,
     Object? other = freezed,
+    Object? messageRetraction = freezed,
   }) {
     return _then(_value.copyWith(
       done: done == freezed
@@ -208,6 +214,10 @@ class _$StanzaHandlerDataCopyWithImpl<$Res>
           ? _value.other
           : other // ignore: cast_nullable_to_non_nullable
               as Map<String, dynamic>,
+      messageRetraction: messageRetraction == freezed
+          ? _value.messageRetraction
+          : messageRetraction // ignore: cast_nullable_to_non_nullable
+              as MessageRetractionData?,
     ));
   }
 }
@@ -240,7 +250,8 @@ abstract class _$$_StanzaHandlerDataCopyWith<$Res>
       bool encrypted,
       ExplicitEncryptionType? encryptionType,
       DelayedDelivery? delayedDelivery,
-      Map<String, dynamic> other});
+      Map<String, dynamic> other,
+      MessageRetractionData? messageRetraction});
 }
 
 /// @nodoc
@@ -277,6 +288,7 @@ class __$$_StanzaHandlerDataCopyWithImpl<$Res>
     Object? encryptionType = freezed,
     Object? delayedDelivery = freezed,
     Object? other = freezed,
+    Object? messageRetraction = freezed,
   }) {
     return _then(_$_StanzaHandlerData(
       done == freezed
@@ -363,6 +375,10 @@ class __$$_StanzaHandlerDataCopyWithImpl<$Res>
           ? _value._other
           : other // ignore: cast_nullable_to_non_nullable
               as Map<String, dynamic>,
+      messageRetraction: messageRetraction == freezed
+          ? _value.messageRetraction
+          : messageRetraction // ignore: cast_nullable_to_non_nullable
+              as MessageRetractionData?,
     ));
   }
 }
@@ -387,7 +403,8 @@ class _$_StanzaHandlerData implements _StanzaHandlerData {
       this.encrypted = false,
       this.encryptionType,
       this.delayedDelivery,
-      final Map<String, dynamic> other = const <String, dynamic>{}})
+      final Map<String, dynamic> other = const <String, dynamic>{},
+      this.messageRetraction})
       : _other = other;
 
 // Indicates to the runner that processing is now done. This means that all
@@ -463,9 +480,14 @@ class _$_StanzaHandlerData implements _StanzaHandlerData {
     return EqualUnmodifiableMapView(_other);
   }
 
+// If non-null, then it indicates the origin Id of the message that should be
+// retracted
+  @override
+  final MessageRetractionData? messageRetraction;
+
   @override
   String toString() {
-    return 'StanzaHandlerData(done: $done, cancel: $cancel, cancelReason: $cancelReason, stanza: $stanza, retransmitted: $retransmitted, sims: $sims, sfs: $sfs, oob: $oob, stableId: $stableId, reply: $reply, chatState: $chatState, isCarbon: $isCarbon, deliveryReceiptRequested: $deliveryReceiptRequested, isMarkable: $isMarkable, fun: $fun, funReplacement: $funReplacement, funCancellation: $funCancellation, encrypted: $encrypted, encryptionType: $encryptionType, delayedDelivery: $delayedDelivery, other: $other)';
+    return 'StanzaHandlerData(done: $done, cancel: $cancel, cancelReason: $cancelReason, stanza: $stanza, retransmitted: $retransmitted, sims: $sims, sfs: $sfs, oob: $oob, stableId: $stableId, reply: $reply, chatState: $chatState, isCarbon: $isCarbon, deliveryReceiptRequested: $deliveryReceiptRequested, isMarkable: $isMarkable, fun: $fun, funReplacement: $funReplacement, funCancellation: $funCancellation, encrypted: $encrypted, encryptionType: $encryptionType, delayedDelivery: $delayedDelivery, other: $other, messageRetraction: $messageRetraction)';
   }
 
   @override
@@ -501,7 +523,9 @@ class _$_StanzaHandlerData implements _StanzaHandlerData {
                 .equals(other.encryptionType, encryptionType) &&
             const DeepCollectionEquality()
                 .equals(other.delayedDelivery, delayedDelivery) &&
-            const DeepCollectionEquality().equals(other._other, this._other));
+            const DeepCollectionEquality().equals(other._other, this._other) &&
+            const DeepCollectionEquality()
+                .equals(other.messageRetraction, messageRetraction));
   }
 
   @override
@@ -527,7 +551,8 @@ class _$_StanzaHandlerData implements _StanzaHandlerData {
         const DeepCollectionEquality().hash(encrypted),
         const DeepCollectionEquality().hash(encryptionType),
         const DeepCollectionEquality().hash(delayedDelivery),
-        const DeepCollectionEquality().hash(_other)
+        const DeepCollectionEquality().hash(_other),
+        const DeepCollectionEquality().hash(messageRetraction)
       ]);
 
   @JsonKey(ignore: true)
@@ -556,7 +581,8 @@ abstract class _StanzaHandlerData implements StanzaHandlerData {
       final bool encrypted,
       final ExplicitEncryptionType? encryptionType,
       final DelayedDelivery? delayedDelivery,
-      final Map<String, dynamic> other}) = _$_StanzaHandlerData;
+      final Map<String, dynamic> other,
+      final MessageRetractionData? messageRetraction}) = _$_StanzaHandlerData;
 
   @override // Indicates to the runner that processing is now done. This means that all
 // pre-processing is done and no other handlers should be consulted.
@@ -606,6 +632,9 @@ abstract class _StanzaHandlerData implements StanzaHandlerData {
   @override // This is for stanza handlers that are not part of the XMPP library but still need
 // pass data around.
   Map<String, dynamic> get other;
+  @override // If non-null, then it indicates the origin Id of the message that should be
+// retracted
+  MessageRetractionData? get messageRetraction;
   @override
   @JsonKey(ignore: true)
   _$$_StanzaHandlerDataCopyWith<_$_StanzaHandlerData> get copyWith =>

packages/moxxmpp/lib/src/managers/namespaces.dart

@@ -24,3 +24,4 @@ const omemoManager = 'org.moxxmpp.omemomanager';
 const emeManager = 'org.moxxmpp.ememanager';
 const cryptographicHashManager = 'org.moxxmpp.cryptographichashmanager';
 const delayedDeliveryManager = 'org.moxxmpp.delayeddeliverymanager';
+const messageRetractionManager = 'org.moxxmpp.messageretractionmanager';

packages/moxxmpp/lib/src/message.dart

@@ -13,12 +13,12 @@ import 'package:moxxmpp/src/xeps/xep_0085.dart';
 import 'package:moxxmpp/src/xeps/xep_0184.dart';
 import 'package:moxxmpp/src/xeps/xep_0333.dart';
 import 'package:moxxmpp/src/xeps/xep_0359.dart';
+import 'package:moxxmpp/src/xeps/xep_0424.dart';
 import 'package:moxxmpp/src/xeps/xep_0446.dart';
 import 'package:moxxmpp/src/xeps/xep_0447.dart';
 import 'package:moxxmpp/src/xeps/xep_0448.dart';
 
 class MessageDetails {
-
   const MessageDetails({
     required this.to,
     this.body,
@@ -35,6 +35,7 @@ class MessageDetails {
     this.funReplacement,
     this.funCancellation,
     this.shouldEncrypt = false,
+    this.messageRetraction,
   });
   final String to;
   final String? body;
@@ -51,6 +52,7 @@ class MessageDetails {
   final String? funReplacement;
   final String? funCancellation;
   final bool shouldEncrypt;
+  final MessageRetractionData? messageRetraction;
 }
 
 class MessageManager extends XmppManagerBase {
@@ -95,6 +97,7 @@ class MessageManager extends XmppManagerBase {
       funReplacement: state.funReplacement,
       funCancellation: state.funCancellation,
       encrypted: state.encrypted,
+      messageRetraction: state.messageRetraction,
       other: state.other,
     ),);
 
@@ -159,6 +162,8 @@ class MessageManager extends XmppManagerBase {
         } else if (firstSource is StatelessFileSharingEncryptedSource) {
           body = firstSource.source.url;
         }
+      } else if (details.messageRetraction?.fallback != null) {
+        body = details.messageRetraction!.fallback;
       }
 
       stanza.addChild(
@@ -216,6 +221,33 @@ class MessageManager extends XmppManagerBase {
         ),
       );
     }
+
+    if (details.messageRetraction != null) {
+      stanza.addChild(
+        XMLNode.xmlns(
+          tag: 'apply-to',
+          xmlns: fasteningXmlns,
+          attributes: <String, String>{
+            'id': details.messageRetraction!.id,
+          },
+          children: [
+            XMLNode.xmlns(
+              tag: 'retract',
+              xmlns: messageRetractionXmlns,
+            ),
+          ],
+        ),
+      );
+
+      if (details.messageRetraction!.fallback != null) {
+        stanza.addChild(
+          XMLNode.xmlns(
+            tag: 'fallback',
+            xmlns: fallbackIndicationXmlns,
+          ),
+        );
+      }
+    }
     
     getAttributes().sendStanza(stanza, awaitable: false);
   }

packages/moxxmpp/lib/src/namespaces.dart

@@ -114,6 +114,15 @@ const simsXmlns = 'urn:xmpp:sims:1';
 // XEP-0420
 const sceXmlns = 'urn:xmpp:sce:1';
 
+// XEP-0422
+const fasteningXmlns = 'urn:xmpp:fasten:0';
+
+// XEP-0424
+const messageRetractionXmlns = 'urn:xmpp:message-retract:0';
+
+// XEp-0428
+const fallbackIndicationXmlns = 'urn:xmpp:fallback:0';
+
 // XEP-0446
 const fileMetadataXmlns = 'urn:xmpp:file:metadata:0';
 

packages/moxxmpp/lib/src/xeps/xep_0424.dart

@@ -0,0 +1,59 @@
+import 'package:moxxmpp/src/managers/base.dart';
+import 'package:moxxmpp/src/managers/data.dart';
+import 'package:moxxmpp/src/managers/handlers.dart';
+import 'package:moxxmpp/src/managers/namespaces.dart';
+import 'package:moxxmpp/src/namespaces.dart';
+import 'package:moxxmpp/src/stanza.dart';
+
+class MessageRetractionData {
+  MessageRetractionData(this.id, this.fallback);
+  final String? fallback;
+  final String id;
+}
+
+class MessageRetractionManager extends XmppManagerBase {
+  @override
+  String getName() => 'MessageRetractionManager';
+
+  @override
+  String getId() => messageRetractionManager;
+
+  @override
+  List<String> getDiscoFeatures() => [ messageRetractionXmlns ];
+
+  @override
+  List<StanzaHandler> getIncomingStanzaHandlers() => [
+    StanzaHandler(
+      stanzaTag: 'message',
+      callback: _onMessage,
+      // Before the MessageManager
+      priority: -99,
+    )
+  ];
+
+  @override
+  Future<bool> isSupported() async => true;
+  
+  Future<StanzaHandlerData> _onMessage(Stanza message, StanzaHandlerData state) async {
+    final applyTo = message.firstTag('apply-to', xmlns: fasteningXmlns);
+    if (applyTo == null) {
+      return state;
+    }
+
+    final retract = applyTo.firstTag('retract', xmlns: messageRetractionXmlns);
+    if (retract == null) {
+      return state;
+    }
+
+    final isFallbackBody = message.firstTag('fallback', xmlns: fallbackIndicationXmlns) != null;
+
+    return state.copyWith(
+      messageRetraction: MessageRetractionData(
+        applyTo.attributes['id']! as String,
+        isFallbackBody ?
+          message.firstTag('body')?.innerText() :
+          null,
+      ),
+    );
+  }
+}