feat: Upgrade omemo_dart to 0.4.0

- moxxmpp@0.1.6+1
 - moxxmpp_socket_tcp@0.1.2+9

.github/FUNDING.yml

@@ -0,0 +1 @@
+ko_fi: papatutuwawa

README.md

@@ -25,3 +25,9 @@ the development shell provided by the NixOS Flake, ensure that `ANDROID_HOME` an
 ## License
 
 See `./LICENSE`.
+
+## Support
+
+If you like what I do and you want to support me, feel free to donate to me on Ko-Fi.
+
+[<img src="https://codeberg.org/moxxy/moxxyv2/raw/branch/master/assets/repo/kofi.png" height="36" style="height: 36px; border: 0px;"></img>](https://ko-fi.com/papatutuwawa)

example/pubspec.yaml

@@ -16,10 +16,10 @@ dependencies:
     version: 0.1.4+1
   moxxmpp:
     hosted: https://git.polynom.me/api/packages/Moxxy/pub
-    version: 0.1.3+1
+    version: 0.1.6+1
   moxxmpp_socket_tcp:
     hosted: https://git.polynom.me/api/packages/Moxxy/pub
-    version: 0.1.2+5
+    version: 0.1.2+9
 
 dev_dependencies:
   flutter_test:

packages/moxxmpp/CHANGELOG.md

@@ -1,3 +1,20 @@
+## 0.1.6+1
+
+ - **FIX**: Fix LMC not working.
+
+## 0.1.6
+
+ - **FEAT**: Implement XEP-0308.
+
+## 0.1.5
+
+ - **FEAT**: Message events now contain the stanza error, if available.
+
+## 0.1.4
+
+ - **FIX**: Only stanza-id required 'sid:0' support.
+ - **FEAT**: Implement parsing and sending of retractions.
+
 ## 0.1.3+1
 
  - **FIX**: Expose the error classes.

packages/moxxmpp/README.md

@@ -5,3 +5,9 @@ A pure-Dart XMPP library written for Moxxy.
 ## License
 
 See `./LICENSE`.
+
+## Support
+
+If you like what I do and you want to support me, feel free to donate to me on Ko-Fi.
+
+[<img src="https://codeberg.org/moxxy/moxxyv2/raw/branch/master/assets/repo/kofi.png" height="36" style="height: 36px; border: 0px;"></img>](https://ko-fi.com/papatutuwawa)

packages/moxxmpp/lib/moxxmpp.dart

@@ -59,6 +59,7 @@ export 'package:moxxmpp/src/xeps/xep_0203.dart';
 export 'package:moxxmpp/src/xeps/xep_0280.dart';
 export 'package:moxxmpp/src/xeps/xep_0297.dart';
 export 'package:moxxmpp/src/xeps/xep_0300.dart';
+export 'package:moxxmpp/src/xeps/xep_0308.dart';
 export 'package:moxxmpp/src/xeps/xep_0333.dart';
 export 'package:moxxmpp/src/xeps/xep_0334.dart';
 export 'package:moxxmpp/src/xeps/xep_0352.dart';
@@ -73,7 +74,10 @@ 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_0444.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';
+export 'package:moxxmpp/src/xeps/xep_0449.dart';
 export 'package:moxxmpp/src/xeps/xep_0461.dart';

packages/moxxmpp/lib/src/events.dart

@@ -6,8 +6,11 @@ import 'package:moxxmpp/src/xeps/xep_0030/types.dart';
 import 'package:moxxmpp/src/xeps/xep_0060/xep_0060.dart';
 import 'package:moxxmpp/src/xeps/xep_0066.dart';
 import 'package:moxxmpp/src/xeps/xep_0085.dart';
+import 'package:moxxmpp/src/xeps/xep_0334.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_0444.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';
@@ -62,6 +65,7 @@ class MessageEvent extends XmppEvent {
     required this.isMarkable,
     required this.encrypted,
     required this.other,
+    this.error,
     this.type,
     this.oob,
     this.sfs,
@@ -71,7 +75,13 @@ class MessageEvent extends XmppEvent {
     this.fun,
     this.funReplacement,
     this.funCancellation,
+    this.messageRetraction,
+    this.messageCorrectionId,
+    this.messageReactions,
+    this.messageProcessingHints,
+    this.stickerPackId,
   });
+  final StanzaError? error;
   final String body;
   final JID fromJid;
   final JID toJid;
@@ -90,6 +100,11 @@ class MessageEvent extends XmppEvent {
   final String? funReplacement;
   final String? funCancellation;
   final bool encrypted;
+  final MessageRetractionData? messageRetraction;
+  final String? messageCorrectionId;
+  final MessageReactions? messageReactions;
+  final List<MessageProcessingHint>? messageProcessingHints;
+  final String? stickerPackId;
   final Map<String, dynamic> other;
 }
 

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

@@ -1,5 +1,4 @@
 import 'dart:async';
-
 import 'package:moxxmpp/src/connection.dart';
 import 'package:moxxmpp/src/events.dart';
 import 'package:moxxmpp/src/jid.dart';
@@ -11,7 +10,6 @@ import 'package:moxxmpp/src/stanza.dart';
 import 'package:moxxmpp/src/stringxml.dart';
 
 class XmppManagerAttributes {
-  
   XmppManagerAttributes({
     required this.sendStanza,
     required this.sendNonza,

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

@@ -6,6 +6,8 @@ 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_0444.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 +57,15 @@ 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,
+      // If non-null, then the message is a correction for the specified stanza Id
+      String? lastMessageCorrectionSid,
+      // Reactions data
+      MessageReactions? messageReactions,
+      // The Id of the sticker pack this sticker belongs to
+      String? stickerPackId,
     }
   ) = _StanzaHandlerData;
 }

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

@@ -54,7 +54,16 @@ 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; // If non-null, then the message is a correction for the specified stanza Id
+  String? get lastMessageCorrectionSid =>
+      throw _privateConstructorUsedError; // Reactions data
+  MessageReactions? get messageReactions =>
+      throw _privateConstructorUsedError; // The Id of the sticker pack this sticker belongs to
+  String? get stickerPackId => throw _privateConstructorUsedError;
 
   @JsonKey(ignore: true)
   $StanzaHandlerDataCopyWith<StanzaHandlerData> get copyWith =>
@@ -87,7 +96,11 @@ abstract class $StanzaHandlerDataCopyWith<$Res> {
       bool encrypted,
       ExplicitEncryptionType? encryptionType,
       DelayedDelivery? delayedDelivery,
-      Map<String, dynamic> other});
+      Map<String, dynamic> other,
+      MessageRetractionData? messageRetraction,
+      String? lastMessageCorrectionSid,
+      MessageReactions? messageReactions,
+      String? stickerPackId});
 }
 
 /// @nodoc
@@ -122,6 +135,10 @@ class _$StanzaHandlerDataCopyWithImpl<$Res>
     Object? encryptionType = freezed,
     Object? delayedDelivery = freezed,
     Object? other = freezed,
+    Object? messageRetraction = freezed,
+    Object? lastMessageCorrectionSid = freezed,
+    Object? messageReactions = freezed,
+    Object? stickerPackId = freezed,
   }) {
     return _then(_value.copyWith(
       done: done == freezed
@@ -208,6 +225,22 @@ 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?,
+      lastMessageCorrectionSid: lastMessageCorrectionSid == freezed
+          ? _value.lastMessageCorrectionSid
+          : lastMessageCorrectionSid // ignore: cast_nullable_to_non_nullable
+              as String?,
+      messageReactions: messageReactions == freezed
+          ? _value.messageReactions
+          : messageReactions // ignore: cast_nullable_to_non_nullable
+              as MessageReactions?,
+      stickerPackId: stickerPackId == freezed
+          ? _value.stickerPackId
+          : stickerPackId // ignore: cast_nullable_to_non_nullable
+              as String?,
     ));
   }
 }
@@ -240,7 +273,11 @@ abstract class _$$_StanzaHandlerDataCopyWith<$Res>
       bool encrypted,
       ExplicitEncryptionType? encryptionType,
       DelayedDelivery? delayedDelivery,
-      Map<String, dynamic> other});
+      Map<String, dynamic> other,
+      MessageRetractionData? messageRetraction,
+      String? lastMessageCorrectionSid,
+      MessageReactions? messageReactions,
+      String? stickerPackId});
 }
 
 /// @nodoc
@@ -277,6 +314,10 @@ class __$$_StanzaHandlerDataCopyWithImpl<$Res>
     Object? encryptionType = freezed,
     Object? delayedDelivery = freezed,
     Object? other = freezed,
+    Object? messageRetraction = freezed,
+    Object? lastMessageCorrectionSid = freezed,
+    Object? messageReactions = freezed,
+    Object? stickerPackId = freezed,
   }) {
     return _then(_$_StanzaHandlerData(
       done == freezed
@@ -363,6 +404,22 @@ class __$$_StanzaHandlerDataCopyWithImpl<$Res>
           ? _value._other
           : other // ignore: cast_nullable_to_non_nullable
               as Map<String, dynamic>,
+      messageRetraction: messageRetraction == freezed
+          ? _value.messageRetraction
+          : messageRetraction // ignore: cast_nullable_to_non_nullable
+              as MessageRetractionData?,
+      lastMessageCorrectionSid: lastMessageCorrectionSid == freezed
+          ? _value.lastMessageCorrectionSid
+          : lastMessageCorrectionSid // ignore: cast_nullable_to_non_nullable
+              as String?,
+      messageReactions: messageReactions == freezed
+          ? _value.messageReactions
+          : messageReactions // ignore: cast_nullable_to_non_nullable
+              as MessageReactions?,
+      stickerPackId: stickerPackId == freezed
+          ? _value.stickerPackId
+          : stickerPackId // ignore: cast_nullable_to_non_nullable
+              as String?,
     ));
   }
 }
@@ -387,7 +444,11 @@ class _$_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,
+      this.lastMessageCorrectionSid,
+      this.messageReactions,
+      this.stickerPackId})
       : _other = other;
 
 // Indicates to the runner that processing is now done. This means that all
@@ -463,9 +524,23 @@ 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;
+// If non-null, then the message is a correction for the specified stanza Id
+  @override
+  final String? lastMessageCorrectionSid;
+// Reactions data
+  @override
+  final MessageReactions? messageReactions;
+// The Id of the sticker pack this sticker belongs to
+  @override
+  final String? stickerPackId;
+
   @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, lastMessageCorrectionSid: $lastMessageCorrectionSid, messageReactions: $messageReactions, stickerPackId: $stickerPackId)';
   }
 
   @override
@@ -501,7 +576,15 @@ 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) &&
+            const DeepCollectionEquality().equals(
+                other.lastMessageCorrectionSid, lastMessageCorrectionSid) &&
+            const DeepCollectionEquality()
+                .equals(other.messageReactions, messageReactions) &&
+            const DeepCollectionEquality()
+                .equals(other.stickerPackId, stickerPackId));
   }
 
   @override
@@ -527,7 +610,11 @@ 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),
+        const DeepCollectionEquality().hash(lastMessageCorrectionSid),
+        const DeepCollectionEquality().hash(messageReactions),
+        const DeepCollectionEquality().hash(stickerPackId)
       ]);
 
   @JsonKey(ignore: true)
@@ -556,7 +643,11 @@ abstract class _StanzaHandlerData implements StanzaHandlerData {
       final bool encrypted,
       final ExplicitEncryptionType? encryptionType,
       final DelayedDelivery? delayedDelivery,
-      final Map<String, dynamic> other}) = _$_StanzaHandlerData;
+      final Map<String, dynamic> other,
+      final MessageRetractionData? messageRetraction,
+      final String? lastMessageCorrectionSid,
+      final MessageReactions? messageReactions,
+      final String? stickerPackId}) = _$_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 +697,15 @@ 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 // If non-null, then the message is a correction for the specified stanza Id
+  String? get lastMessageCorrectionSid;
+  @override // Reactions data
+  MessageReactions? get messageReactions;
+  @override // The Id of the sticker pack this sticker belongs to
+  String? get stickerPackId;
   @override
   @JsonKey(ignore: true)
   _$$_StanzaHandlerDataCopyWith<_$_StanzaHandlerData> get copyWith =>

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

@@ -24,3 +24,7 @@ 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';
+const lastMessageCorrectionManager = 'org.moxxmpp.lastmessagecorrectionmanager';
+const messageReactionsManager = 'org.moxxmpp.messagereactionsmanager';
+const stickersManager = 'org.moxxmpp.stickersmanager';

packages/moxxmpp/lib/src/message.dart

@@ -11,14 +11,22 @@ import 'package:moxxmpp/src/xeps/staging/file_upload_notification.dart';
 import 'package:moxxmpp/src/xeps/xep_0066.dart';
 import 'package:moxxmpp/src/xeps/xep_0085.dart';
 import 'package:moxxmpp/src/xeps/xep_0184.dart';
+import 'package:moxxmpp/src/xeps/xep_0308.dart';
 import 'package:moxxmpp/src/xeps/xep_0333.dart';
+import 'package:moxxmpp/src/xeps/xep_0334.dart';
 import 'package:moxxmpp/src/xeps/xep_0359.dart';
+import 'package:moxxmpp/src/xeps/xep_0424.dart';
+import 'package:moxxmpp/src/xeps/xep_0444.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';
 
+/// Data used to build a message stanza.
+///
+/// [setOOBFallbackBody] indicates, when using SFS, whether a OOB fallback should be
+/// added. This is recommended when sharing files but may cause issues when the message
+/// stanza should include a SFS element without any fallbacks.
 class MessageDetails {
-
   const MessageDetails({
     required this.to,
     this.body,
@@ -35,6 +43,12 @@ class MessageDetails {
     this.funReplacement,
     this.funCancellation,
     this.shouldEncrypt = false,
+    this.messageRetraction,
+    this.lastMessageCorrectionId,
+    this.messageReactions,
+    this.messageProcessingHints,
+    this.stickerPackId,
+    this.setOOBFallbackBody = true,
   });
   final String to;
   final String? body;
@@ -51,6 +65,12 @@ class MessageDetails {
   final String? funReplacement;
   final String? funCancellation;
   final bool shouldEncrypt;
+  final MessageRetractionData? messageRetraction;
+  final String? lastMessageCorrectionId;
+  final MessageReactions? messageReactions;
+  final String? stickerPackId;
+  final List<MessageProcessingHint>? messageProcessingHints;
+  final bool setOOBFallbackBody;
 }
 
 class MessageManager extends XmppManagerBase {
@@ -76,6 +96,11 @@ class MessageManager extends XmppManagerBase {
     final message = state.stanza;
     final body = message.firstTag('body');
 
+    final hints = List<MessageProcessingHint>.empty(growable: true);
+    for (final element in message.findTagsByXmlns(messageProcessingHintsXmlns)) {
+      hints.add(messageProcessingHintFromXml(element)); 
+    }
+    
     getAttributes().sendEvent(MessageEvent(
       body: body != null ? body.innerText() : '',
       fromJid: JID.fromString(message.attributes['from']! as String),
@@ -95,7 +120,15 @@ class MessageManager extends XmppManagerBase {
       funReplacement: state.funReplacement,
       funCancellation: state.funCancellation,
       encrypted: state.encrypted,
+      messageRetraction: state.messageRetraction,
+      messageCorrectionId: state.lastMessageCorrectionSid,
+      messageReactions: state.messageReactions,
+      messageProcessingHints: hints.isEmpty ?
+        null :
+        hints,
+      stickerPackId: state.stickerPackId,
       other: state.other,
+      error: StanzaError.fromStanza(message),
     ),);
 
     return state.copyWith(done: true);
@@ -151,7 +184,7 @@ class MessageManager extends XmppManagerBase {
         );
     } else {
       var body = details.body;
-      if (details.sfs != null) {
+      if (details.sfs != null && details.setOOBFallbackBody) {
         // TODO(Unknown): Maybe find a better solution
         final firstSource = details.sfs!.sources.first;
         if (firstSource is StatelessFileSharingUrlSource) {
@@ -159,11 +192,15 @@ 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(
-        XMLNode(tag: 'body', text: body),
-      );
+      if (body != null) {
+        stanza.addChild(
+          XMLNode(tag: 'body', text: body),
+        );
+      }
     }
 
     if (details.requestDeliveryReceipt) {
@@ -180,7 +217,7 @@ class MessageManager extends XmppManagerBase {
       stanza.addChild(details.sfs!.toXML());
 
       final source = details.sfs!.sources.first;
-      if (source is StatelessFileSharingUrlSource) {
+      if (source is StatelessFileSharingUrlSource && details.setOOBFallbackBody) {
         // SFS recommends OOB as a fallback
         stanza.addChild(constructOOBNode(OOBData(url: source.url)));
       }
@@ -216,6 +253,63 @@ 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,
+          ),
+        );
+      }
+    }
+
+    if (details.lastMessageCorrectionId != null) {
+      stanza.addChild(
+        makeLastMessageCorrectionEdit(
+          details.lastMessageCorrectionId!,
+        ),
+      );
+    }
+
+    if (details.messageReactions != null) {
+      stanza.addChild(details.messageReactions!.toXml());
+    }
+    
+    if (details.messageProcessingHints != null) {
+      for (final hint in details.messageProcessingHints!) {
+        stanza.addChild(hint.toXml());
+      }
+    }
+
+    if (details.stickerPackId != null) {
+      stanza.addChild(
+        XMLNode.xmlns(
+          tag: 'sticker',
+          xmlns: stickersXmlns,
+          attributes: {
+            'pack': details.stickerPackId!,
+          },
+        ),
+      );
+    }
     
     getAttributes().sendStanza(stanza, awaitable: false);
   }

packages/moxxmpp/lib/src/namespaces.dart

@@ -76,6 +76,9 @@ const hashSha3512 = 'sha3-512';
 const hashBlake2b256 = 'blake2b-256';
 const hashBlake2b512 = 'blake2b-512';
 
+// XEP-0308
+const lmcXmlns = 'urn:xmpp:message-correct:0';
+
 // XEP-0333
 const chatMarkersXmlns = 'urn:xmpp:chat-markers:0';
 
@@ -114,6 +117,18 @@ 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-0444
+const messageReactionsXmlns = 'urn:xmpp:reactions:0';
+
 // XEP-0446
 const fileMetadataXmlns = 'urn:xmpp:file:metadata:0';
 
@@ -126,6 +141,9 @@ const sfsEncryptionAes128GcmNoPaddingXmlns = 'urn:xmpp:ciphers:aes-128-gcm-nopad
 const sfsEncryptionAes256GcmNoPaddingXmlns = 'urn:xmpp:ciphers:aes-256-gcm-nopadding:0';
 const sfsEncryptionAes256CbcPkcs7Xmlns = 'urn:xmpp:ciphers:aes-256-cbc-pkcs7:0';
 
+// XEP-0449
+const stickersXmlns = 'urn:xmpp:stickers:0';
+
 // XEP-0461
 const replyXmlns = 'urn:xmpp:reply:0';
 const fallbackXmlns = 'urn:xmpp:feature-fallback:0';

packages/moxxmpp/lib/src/rfcs/rfc_4790.dart

@@ -24,3 +24,28 @@ int ioctetSortComparator(String a, String b) {
   
   return 1;
 }
+
+int ioctetSortComparatorRaw(List<int> a, List<int> b) {
+  if (a.isEmpty && b.isEmpty) {
+    return 0;
+  }
+
+  if (a.isEmpty && b.isNotEmpty) {
+    return -1;
+  }
+
+  if (a.isNotEmpty && b.isEmpty) {
+    return 1;
+  }
+
+  if (a[0] == b[0]) {
+    return ioctetSortComparatorRaw(a.sublist(1), b.sublist(1));
+  }
+
+  // TODO(Unknown): Is this correct?
+  if (a[0] < b[0]) {
+    return -1;
+  }
+  
+  return 1;
+}

packages/moxxmpp/lib/src/stanza.dart

@@ -1,6 +1,28 @@
 import 'package:moxxmpp/src/namespaces.dart';
 import 'package:moxxmpp/src/stringxml.dart';
 
+/// A simple description of the <error /> element that may be inside a stanza
+class StanzaError {
+  StanzaError(this.type, this.error);
+  String type;
+  String error;
+
+  /// Returns a StanzaError if [stanza] contains a <error /> element. If not, returns
+  /// null.
+  static StanzaError? fromStanza(Stanza stanza) {
+    final error = stanza.firstTag('error');
+    if (error == null) return null;
+
+    final stanzaError = error.firstTagByXmlns(fullStanzaXmlns);
+    if (stanzaError == null) return null;
+
+    return StanzaError(
+      error.attributes['type']! as String,
+      stanzaError.tag,
+    );
+  }
+}
+
 class Stanza extends XMLNode {
   // ignore: use_super_parameters
   Stanza({ this.to, this.from, this.type, this.id, List<XMLNode> children = const [], required String tag, Map<String, String> attributes = const {} }) : super(

packages/moxxmpp/lib/src/stringxml.dart

@@ -129,6 +129,12 @@ class XMLNode {
     }).toList();
   }
   
+  List<XMLNode> findTagsByXmlns(String xmlns) {
+    return children
+      .where((element) => element.attributes['xmlns'] == xmlns)
+      .toList();
+  }
+  
   /// Returns the inner text of the node. If none is set, returns the "".
   String innerText() {
     return text ?? '';

packages/moxxmpp/lib/src/xeps/xep_0030/xep_0030.dart

@@ -289,7 +289,7 @@ class DiscoManager extends XmppManagerBase {
   }
   
   /// Sends a disco info query to the (full) jid [entity], optionally with node=[node].
-  Future<Result<DiscoError, DiscoInfo>> discoInfoQuery(String entity, { String? node}) async {
+  Future<Result<DiscoError, DiscoInfo>> discoInfoQuery(String entity, { String? node, bool shouldEncrypt = true }) async {
     final cacheKey = DiscoCacheKey(entity, node);
     DiscoInfo? info;
     Completer<Result<DiscoError, DiscoInfo>>? completer;
@@ -316,6 +316,7 @@ class DiscoManager extends XmppManagerBase {
 
     final stanza = await getAttributes().sendStanza(
       buildDiscoInfoQueryStanza(entity, node),
+      encrypted: !shouldEncrypt,
     );
     final query = stanza.firstTag('query');
     if (query == null) {
@@ -359,9 +360,12 @@ class DiscoManager extends XmppManagerBase {
   }
 
   /// Sends a disco items query to the (full) jid [entity], optionally with node=[node].
-  Future<Result<DiscoError, List<DiscoItem>>> discoItemsQuery(String entity, { String? node }) async {
+  Future<Result<DiscoError, List<DiscoItem>>> discoItemsQuery(String entity, { String? node, bool shouldEncrypt = true }) async {
     final stanza = await getAttributes()
-      .sendStanza(buildDiscoItemsQueryStanza(entity, node: node)) as Stanza;
+      .sendStanza(
+        buildDiscoItemsQueryStanza(entity, node: node),
+        encrypted: !shouldEncrypt,
+      ) as Stanza;
 
     final query = stanza.firstTag('query');
     if (query == null) return Result(InvalidResponseDiscoError());

packages/moxxmpp/lib/src/xeps/xep_0054.dart

@@ -7,15 +7,20 @@ import 'package:moxxmpp/src/managers/namespaces.dart';
 import 'package:moxxmpp/src/namespaces.dart';
 import 'package:moxxmpp/src/stanza.dart';
 import 'package:moxxmpp/src/stringxml.dart';
+import 'package:moxxmpp/src/types/result.dart';
+
+abstract class VCardError {}
+
+class UnknownVCardError extends VCardError {}
+
+class InvalidVCardError extends VCardError {}
 
 class VCardPhoto {
-
   const VCardPhoto({ this.binval });
   final String? binval;
 }
 
 class VCard {
-
   const VCard({ this.nickname, this.url, this.photo });
   final String? nickname;
   final String? url;
@@ -23,7 +28,6 @@ class VCard {
 }
 
 class VCardManager extends XmppManagerBase {
-
   VCardManager() : _lastHash = {}, super();
   final Map<String, String> _lastHash;
   
@@ -59,12 +63,18 @@ class VCardManager extends XmppManagerBase {
     final lastHash = _lastHash[from];
     if (lastHash != hash) {
       _lastHash[from] = hash;
-      final vcard = await requestVCard(from);
+      final vcardResult = await requestVCard(from);
 
-      if (vcard != null) {
-        final binval = vcard.photo?.binval;
+      if (vcardResult.isType<VCard>()) {
+        final binval = vcardResult.get<VCard>().photo?.binval;
         if (binval != null) {
-          getAttributes().sendEvent(AvatarUpdatedEvent(jid: from, base64: binval, hash: hash));
+          getAttributes().sendEvent(
+            AvatarUpdatedEvent(
+              jid: from,
+              base64: binval,
+              hash: hash,
+            ),
+          );
         } else {
           logger.warning('No avatar data found');
         }
@@ -95,7 +105,7 @@ class VCardManager extends XmppManagerBase {
     );
   }
   
-  Future<VCard?> requestVCard(String jid) async {
+  Future<Result<VCardError, VCard>> requestVCard(String jid) async {
     final result = await getAttributes().sendStanza(
       Stanza.iq(
         to: jid,
@@ -107,12 +117,13 @@ class VCardManager extends XmppManagerBase {
           )
         ],
       ),
+      encrypted: true,
     );
 
-    if (result.attributes['type'] != 'result') return null;
+    if (result.attributes['type'] != 'result') return Result(UnknownVCardError());
     final vcard = result.firstTag('vCard', xmlns: vCardTempXmlns);
-    if (vcard == null) return null;
+    if (vcard == null) return Result(UnknownVCardError());
     
-    return _parseVCard(vcard);
+    return Result(_parseVCard(vcard));
   } 
 }

packages/moxxmpp/lib/src/xeps/xep_0060/xep_0060.dart

@@ -16,7 +16,6 @@ import 'package:moxxmpp/src/xeps/xep_0060/errors.dart';
 import 'package:moxxmpp/src/xeps/xep_0060/helpers.dart';
 
 class PubSubPublishOptions {
-
   const PubSubPublishOptions({
     this.accessModel,
     this.maxItems,
@@ -60,7 +59,6 @@ class PubSubPublishOptions {
 }
 
 class PubSubItem {
-
   const PubSubItem({ required this.id, required this.node, required this.payload });
   final String id;
   final String node;

packages/moxxmpp/lib/src/xeps/xep_0084.dart

@@ -3,21 +3,24 @@ import 'package:moxxmpp/src/managers/base.dart';
 import 'package:moxxmpp/src/managers/namespaces.dart';
 import 'package:moxxmpp/src/namespaces.dart';
 import 'package:moxxmpp/src/stringxml.dart';
+import 'package:moxxmpp/src/types/result.dart';
 import 'package:moxxmpp/src/xeps/xep_0030/errors.dart';
 import 'package:moxxmpp/src/xeps/xep_0030/types.dart';
 import 'package:moxxmpp/src/xeps/xep_0030/xep_0030.dart';
 import 'package:moxxmpp/src/xeps/xep_0060/errors.dart';
 import 'package:moxxmpp/src/xeps/xep_0060/xep_0060.dart';
 
-class UserAvatar {
+abstract class AvatarError {}
 
+class UnknownAvatarError extends AvatarError {}
+
+class UserAvatar {
   const UserAvatar({ required this.base64, required this.hash });
   final String base64;
   final String hash;
 }
 
 class UserAvatarMetadata {
-
   const UserAvatarMetadata(
     this.id,
     this.length,
@@ -62,30 +65,30 @@ class UserAvatarManager extends XmppManagerBase {
   // TODO(PapaTutuWawa): Check for PEP support
   @override
   Future<bool> isSupported() async => true;
-  
+
   /// Requests the avatar from [jid]. Returns the avatar data if the request was
   /// successful. Null otherwise
-  // TODO(Unknown): Migrate to Resultsv2
-  Future<UserAvatar?> getUserAvatar(String jid) async {
+  Future<Result<AvatarError, UserAvatar>> getUserAvatar(String jid) async {
     final pubsub = _getPubSubManager();
     final resultsRaw = await pubsub.getItems(jid, userAvatarDataXmlns);
-    if (resultsRaw.isType<PubSubError>()) return null;
+    if (resultsRaw.isType<PubSubError>()) return Result(UnknownAvatarError());
 
     final results = resultsRaw.get<List<PubSubItem>>();
-    if (results.isEmpty) return null;
+    if (results.isEmpty) return Result(UnknownAvatarError());
 
     final item = results[0];
-    return UserAvatar(
-      base64: item.payload.innerText(),
-      hash: item.id,
+    return Result(
+      UserAvatar(
+        base64: item.payload.innerText(),
+        hash: item.id,
+      ),
     );
   }
 
   /// Publish the avatar data, [base64], on the pubsub node using [hash] as
   /// the item id. [hash] must be the SHA-1 hash of the image data, while
   /// [base64] must be the base64-encoded version of the image data.
-  // TODO(Unknown): Migrate to Resultsv2
-  Future<bool> publishUserAvatar(String base64, String hash, bool public) async {
+  Future<Result<AvatarError, bool>> publishUserAvatar(String base64, String hash, bool public) async {
     final pubsub = _getPubSubManager();
     final result = await pubsub.publish(
       getAttributes().getFullJID().toBare().toString(),
@@ -101,14 +104,15 @@ class UserAvatarManager extends XmppManagerBase {
       ),
     );
 
-    return !result.isType<PubSubError>();
+    if (result.isType<PubSubError>()) return Result(UnknownAvatarError());
+    
+    return const Result(true);
   }
 
   /// Publish avatar metadata [metadata] to the User Avatar's metadata node. If [public]
   /// is true, then the node will be set to an 'open' access model. If [public] is false,
   /// then the node will be set to an 'roster' access model.
-  // TODO(Unknown): Migrate to Resultsv2
-  Future<bool> publishUserAvatarMetadata(UserAvatarMetadata metadata, bool public) async {
+  Future<Result<AvatarError, bool>> publishUserAvatarMetadata(UserAvatarMetadata metadata, bool public) async {
     final pubsub = _getPubSubManager();
     final result = await pubsub.publish(
       getAttributes().getFullJID().toBare().toString(),
@@ -135,39 +139,37 @@ class UserAvatarManager extends XmppManagerBase {
       ),
     );
 
-    return result.isType<PubSubError>();
+    if (result.isType<PubSubError>()) return Result(UnknownAvatarError());
+    return const Result(true);
   }
   
   /// Subscribe the data and metadata node of [jid].
-  // TODO(Unknown): Migrate to Resultsv2
-  Future<bool> subscribe(String jid) async {
+  Future<Result<AvatarError, bool>> subscribe(String jid) async {
     await _getPubSubManager().subscribe(jid, userAvatarDataXmlns);
     await _getPubSubManager().subscribe(jid, userAvatarMetadataXmlns);
 
-    return true;
+    return const Result(true);
   }
 
   /// Unsubscribe the data and metadata node of [jid].
-  // TODO(Unknown): Migrate to Resultsv2
-  Future<bool> unsubscribe(String jid) async {
+  Future<Result<AvatarError, bool>> unsubscribe(String jid) async {
     await _getPubSubManager().unsubscribe(jid, userAvatarDataXmlns);
     await _getPubSubManager().subscribe(jid, userAvatarMetadataXmlns);
 
-    return true;
+    return const Result(true);
   }
 
   /// Returns the PubSub Id of an avatar after doing a disco#items query.
   /// Note that this assumes that there is only one (1) item published on
   /// the node.
-  // TODO(Unknown): Migrate to Resultsv2
-  Future<String?> getAvatarId(String jid) async {
+  Future<Result<AvatarError, String>> getAvatarId(String jid) async {
     final disco = getAttributes().getManagerById(discoManager)! as DiscoManager;
-    final response = await disco.discoItemsQuery(jid, node: userAvatarDataXmlns);
-    if (response.isType<DiscoError>()) return null;
+    final response = await disco.discoItemsQuery(jid, node: userAvatarDataXmlns, shouldEncrypt: false);
+    if (response.isType<DiscoError>()) return Result(UnknownAvatarError());
 
     final items = response.get<List<DiscoItem>>();
-    if (items.isEmpty) return null;
+    if (items.isEmpty) return Result(UnknownAvatarError());
 
-    return items.first.name;
+    return Result(items.first.name);
   }
 }

packages/moxxmpp/lib/src/xeps/xep_0203.dart

@@ -8,14 +8,12 @@ import 'package:moxxmpp/src/stanza.dart';
 
 @immutable
 class DelayedDelivery {
-
   const DelayedDelivery(this.from, this.timestamp);
   final DateTime timestamp;
   final String from;
 }
 
 class DelayedDeliveryManager extends XmppManagerBase {
-
   @override
   String getId() => delayedDeliveryManager;
 

packages/moxxmpp/lib/src/xeps/xep_0308.dart

@@ -0,0 +1,50 @@
+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';
+import 'package:moxxmpp/src/stringxml.dart';
+
+XMLNode makeLastMessageCorrectionEdit(String id) {
+  return XMLNode.xmlns(
+    tag: 'replace',
+    xmlns: lmcXmlns,
+    attributes: <String, String>{
+      'id': id,
+    },
+  );
+}
+
+class LastMessageCorrectionManager extends XmppManagerBase {
+  @override
+  String getName() => 'LastMessageCorrectionManager';
+
+  @override
+  String getId() => lastMessageCorrectionManager;
+
+  @override
+  List<String> getDiscoFeatures() => [ lmcXmlns ];
+  
+  @override
+  List<StanzaHandler> getIncomingStanzaHandlers() => [
+    StanzaHandler(
+      stanzaTag: 'message',
+      tagName: 'replace',
+      tagXmlns: lmcXmlns,
+      callback: _onMessage,
+      // Before the message handler
+      priority: -99,
+    )
+  ];
+
+  @override
+  Future<bool> isSupported() async => true;
+  
+  Future<StanzaHandlerData> _onMessage(Stanza stanza, StanzaHandlerData state) async {
+    final edit = stanza.firstTag('replace', xmlns: lmcXmlns)!;
+    return state.copyWith(
+      lastMessageCorrectionSid: edit.attributes['id']! as String,
+    );
+  }
+}

packages/moxxmpp/lib/src/xeps/xep_0334.dart

@@ -8,8 +8,18 @@ enum MessageProcessingHint {
   store,
 }
 
-/// NOTE: We do not define a function for turning a Message Processing Hint element into
-///       an enum value since the elements do not concern us as a client.
+MessageProcessingHint messageProcessingHintFromXml(XMLNode element) {
+  switch (element.tag) {
+    case 'no-permanent-store': return MessageProcessingHint.noPermanentStore;
+    case 'no-store': return MessageProcessingHint.noStore;
+    case 'no-copy': return MessageProcessingHint.noCopies;
+    case 'store': return MessageProcessingHint.store;
+  }
+    
+  assert(false, 'Invalid Message Processing Hint: ${element.tag}');
+  return MessageProcessingHint.noStore;
+}
+
 extension XmlExtension on MessageProcessingHint {
   XMLNode toXml() {
     String tag;

packages/moxxmpp/lib/src/xeps/xep_0359.dart

@@ -58,8 +58,16 @@ class StableIdManager extends XmppManagerBase {
     String? stanzaIdBy;
     final originIdTag = message.firstTag('origin-id', xmlns: stableIdXmlns);
     final stanzaIdTag = message.firstTag('stanza-id', xmlns: stableIdXmlns);
-    if (originIdTag != null || stanzaIdTag != null) {
-      logger.finest('Found Unique and Stable Stanza Id tag');
+
+    // Process the origin id
+    if (originIdTag != null) {
+      logger.finest('Found origin Id tag');
+      originId = originIdTag.attributes['id']! as String;
+    }
+
+    // Process the stanza id tag
+    if (stanzaIdTag != null) {
+      logger.finest('Found stanza Id tag');
       final attrs = getAttributes();
       final disco = attrs.getManagerById<DiscoManager>(discoManager)!;
       final result = await disco.discoInfoQuery(from.toString());
@@ -68,17 +76,10 @@ class StableIdManager extends XmppManagerBase {
         logger.finest('Got info for ${from.toString()}');
         if (info.features.contains(stableIdXmlns)) {
           logger.finest('${from.toString()} supports $stableIdXmlns.');
-
-          if (originIdTag != null) {
-            originId = originIdTag.attributes['id']! as String;
-          }
-
-          if (stanzaIdTag != null) {
-            stanzaId = stanzaIdTag.attributes['id']! as String;
-            stanzaIdBy = stanzaIdTag.attributes['by']! as String;
-          }
+          stanzaId = stanzaIdTag.attributes['id']! as String;
+          stanzaIdBy = stanzaIdTag.attributes['by']! as String;
         } else {
-          logger.finest('${from.toString()} does not support $stableIdXmlns. Ignoring... ');
+          logger.finest('${from.toString()} does not support $stableIdXmlns. Ignoring stanza id... ');
         }
       } else {
         logger.finest('Failed to find out if ${from.toString()} supports $stableIdXmlns. Ignoring... ');

packages/moxxmpp/lib/src/xeps/xep_0384/xep_0384.dart

@@ -1,8 +1,6 @@
 import 'dart:async';
-import 'dart:collection';
 import 'dart:convert';
 import 'package:meta/meta.dart';
-import 'package:moxlib/moxlib.dart';
 import 'package:moxxmpp/src/events.dart';
 import 'package:moxxmpp/src/jid.dart';
 import 'package:moxxmpp/src/managers/base.dart';
@@ -25,7 +23,6 @@ import 'package:moxxmpp/src/xeps/xep_0384/errors.dart';
 import 'package:moxxmpp/src/xeps/xep_0384/helpers.dart';
 import 'package:moxxmpp/src/xeps/xep_0384/types.dart';
 import 'package:omemo_dart/omemo_dart.dart';
-import 'package:synchronized/synchronized.dart';
 
 const _doNotEncryptList = [
   // XEP-0033
@@ -43,17 +40,7 @@ const _doNotEncryptList = [
   DoNotEncrypt('stanza-id', stableIdXmlns),
 ];
 
-abstract class OmemoManager extends XmppManagerBase {
-  OmemoManager() : _handlerLock = Lock(), _handlerFutures = {}, super();
-
-  final Lock _handlerLock;
-  final Map<JID, Queue<Completer<void>>> _handlerFutures;
-
-  final Map<JID, List<int>> _deviceMap = {};
-
-  // Mapping whether we already tried to subscribe to the JID's devices node
-  final Map<JID, bool> _subscriptionMap = {};
-  
+abstract class BaseOmemoManager extends XmppManagerBase {
   @override
   String getId() => omemoManager;
 
@@ -127,60 +114,31 @@ abstract class OmemoManager extends XmppManagerBase {
       } else {
         // Someone published to their device list node
         logger.finest('Got devices $ids');
-        _deviceMap[jid] = ids;
       }
 
+      // Tell the OmemoManager
+      (await getOmemoManager())
+        .onDeviceListUpdate(jid.toString(), ids);
+
       // Generate an event
       getAttributes().sendEvent(OmemoDeviceListUpdatedEvent(jid, ids));
     }
   }
-  
+
   @visibleForOverriding
-  Future<OmemoSessionManager> getSessionManager();
+  Future<OmemoManager> getOmemoManager();
 
-  /// Wrapper around using getSessionManager and then calling encryptToJids on it.
-  Future<EncryptionResult> _encryptToJids(List<String> jids, String? plaintext, { List<OmemoBundle>? newSessions }) async {
-    final session = await getSessionManager();
-    return session.encryptToJids(jids, plaintext, newSessions: newSessions);
-  }
-
-  /// Wrapper around using getSessionManager and then calling encryptToJids on it.
-  Future<String?> _decryptMessage(List<int>? ciphertext, String senderJid, int senderDeviceId, List<EncryptedKey> keys, int sendTimestamp) async {
-    final session = await getSessionManager();
-    return session.decryptMessage(
-      ciphertext,
-      senderJid,
-      senderDeviceId,
-      keys,
-      sendTimestamp,
-    );
-  }
   
   /// Wrapper around using getSessionManager and then calling getDeviceId on it.
-  Future<int> _getDeviceId() async {
-    final session = await getSessionManager();
-    return session.getDeviceId();
-  }
+  Future<int> _getDeviceId() async => (await getOmemoManager()).getDeviceId();
 
   /// Wrapper around using getSessionManager and then calling getDeviceId on it.
   Future<OmemoBundle> _getDeviceBundle() async {
-    final session = await getSessionManager();
-    return session.getDeviceBundle();
+    final om = await getOmemoManager();
+    final device = await om.getDevice();
+    return device.toBundle();
   }
 
-  /// Wrapper around using getSessionManager and then calling isRatchetAcknowledged on it.
-  Future<bool> _isRatchetAcknowledged(String jid, int deviceId) async {
-    final session = await getSessionManager();
-    return session.isRatchetAcknowledged(jid, deviceId);
-  }
-
-  /// Wrapper around checking if [jid] appears in the session manager's device map.
-  Future<bool> _hasSessionWith(String jid) async {
-    final session = await getSessionManager();
-    final deviceMap = await session.getDeviceMap();
-    return deviceMap.containsKey(jid);
-  }
-  
   /// Determines what child elements of a stanza should be encrypted. If shouldEncrypt
   /// returns true for [element], then [element] will be encrypted. If shouldEncrypt
   /// returns false, then [element] won't be encrypted.
@@ -205,56 +163,51 @@ abstract class OmemoManager extends XmppManagerBase {
   /// an attached payload, if [children] is not null, or an empty OMEMO message if
   /// [children] is null. This function takes care of creating the affix elements as
   /// specified by both XEP-0420 and XEP-0384.
-  /// [jids] is the list of JIDs the payload should be encrypted for.
-  Future<XMLNode> _encryptChildren(List<XMLNode>? children, List<String> jids, String toJid, List<OmemoBundle> newSessions) async {
-    XMLNode? payload;
-    if (children != null) {
-      payload = XMLNode.xmlns(
-        tag: 'envelope',
-        xmlns: sceXmlns,
-        children: [
-          XMLNode(
-            tag: 'content',
-            children: children,
-          ),
+  /// [toJid] is the list of JIDs the payload should be encrypted for.
+  String _buildEnvelope(List<XMLNode> children, String toJid) {
+    final payload = XMLNode.xmlns(
+      tag: 'envelope',
+      xmlns: sceXmlns,
+      children: [
+        XMLNode(
+          tag: 'content',
+          children: children,
+        ),
 
-          XMLNode(
-            tag: 'rpad',
-            text: generateRpad(),
-          ),
-          XMLNode(
-            tag: 'to',
-            attributes: <String, String>{
-              'jid': toJid,
-            },
-          ),
-          XMLNode(
-            tag: 'from',
-            attributes: <String, String>{
-              'jid': getAttributes().getFullJID().toString(),
-            },
-          ),
-          /*
-          XMLNode(
-            tag: 'time',
-            // TODO(Unknown): Implement
-            attributes: <String, String>{
-              'stamp': '',
-            },
-          ),
-          */
-        ],
-      );
-    }
-
-    final encryptedEnvelope = await _encryptToJids(
-      jids,
-      payload?.toXml(),
-      newSessions: newSessions,
+        XMLNode(
+          tag: 'rpad',
+          text: generateRpad(),
+        ),
+        XMLNode(
+          tag: 'to',
+          attributes: <String, String>{
+            'jid': toJid,
+          },
+        ),
+        XMLNode(
+          tag: 'from',
+          attributes: <String, String>{
+            'jid': getAttributes().getFullJID().toString(),
+          },
+        ),
+        /*
+        XMLNode(
+          tag: 'time',
+          // TODO(Unknown): Implement
+          attributes: <String, String>{
+            'stamp': '',
+          },
+        ),
+        */
+      ],
     );
 
+    return payload.toXml();
+  }
+
+  XMLNode _buildEncryptedElement(EncryptionResult result, String recipientJid, int deviceId) {
     final keyElements = <String, List<XMLNode>>{};
-    for (final key in encryptedEnvelope.encryptedKeys) {
+    for (final key in result.encryptedKeys) {
       final keyElement = XMLNode(
         tag: 'key',
         attributes: <String, String>{
@@ -282,11 +235,11 @@ abstract class OmemoManager extends XmppManagerBase {
     }).toList();
 
     var payloadElement = <XMLNode>[];
-    if (payload != null) {
+    if (result.ciphertext != null) {
       payloadElement = [
         XMLNode(
           tag: 'payload',
-          text: base64.encode(encryptedEnvelope.ciphertext!),
+          text: base64.encode(result.ciphertext!),
         ),
       ];
     }
@@ -299,7 +252,7 @@ abstract class OmemoManager extends XmppManagerBase {
         XMLNode(
           tag: 'header',
           attributes: <String, String>{
-            'sid': (await _getDeviceId()).toString(),
+            'sid': deviceId.toString(),
           },
           children: keysElements,
         ),
@@ -307,136 +260,18 @@ abstract class OmemoManager extends XmppManagerBase {
     );
   }
 
-  /// A logging wrapper around acking the ratchet with [jid] with identifier [deviceId].
-  Future<void> _ackRatchet(String jid, int deviceId) async {
-    logger.finest('Acking ratchet $jid:$deviceId');
-    final session = await getSessionManager();
-    await session.ratchetAcknowledged(jid, deviceId);
-  }
-
-  /// Figure out if new sessions need to be built. [toJid] is the JID of the entity we
-  /// want to send a message to. [children] refers to the unencrypted children of the
-  /// message. They are required to be passed because shouldIgnoreUnackedRatchets is
-  /// called here.
-  ///
-  /// Either returns a list of bundles we "need" to build a session with or an OmemoError.
-  Future<Result<OmemoError, List<OmemoBundle>>> _findNewSessions(JID toJid, List<XMLNode> children) async {
-    final ownJid = getAttributes().getFullJID().toBare();
-    final session = await getSessionManager();
-    final ownId = await session.getDeviceId();
-
-    // Ignore our own device if it is the only published device on our devices node
-    if (toJid.toBare() == ownJid) {
-      final deviceList = await getDeviceList(ownJid);
-      if (deviceList.isType<List<int>>()) {
-        final devices = deviceList.get<List<int>>();
-        if (devices.length == 1 && devices.first == ownId) {
-          return const Result(<OmemoBundle>[]);
-        }
-      }
-    }
-
-    final newSessions = List<OmemoBundle>.empty(growable: true);
-    final sessionAvailable = await _hasSessionWith(toJid.toString());   
-    if (!sessionAvailable) {
-      logger.finest('No session for $toJid. Retrieving bundles to build a new session.');
-      final result = await retrieveDeviceBundles(toJid);
-      if (result.isType<List<OmemoBundle>>()) {
-        final bundles = result.get<List<OmemoBundle>>();
-
-        if (ownJid == toJid) {
-          logger.finest('Requesting bundles for own JID. Ignoring current device');
-          newSessions.addAll(bundles.where((bundle) => bundle.id != ownId));
-        } else {
-          newSessions.addAll(bundles);
-        }
-      } else {
-        logger.warning('Failed to retrieve device bundles for $toJid');
-        return Result(OmemoNotSupportedForContactException());
-      }
-
-      if (!_subscriptionMap.containsKey(toJid)) {
-        await subscribeToDeviceList(toJid);
-      }
-    } else {
-      final toBare = toJid.toBare();
-      final ratchetSessions = (await session.getDeviceMap())[toBare.toString()]!;
-      final deviceMapRaw = await getDeviceList(toBare);
-      if (!_subscriptionMap.containsKey(toBare)) {
-        unawaited(subscribeToDeviceList(toBare));
-      }
-
-      if (deviceMapRaw.isType<OmemoError>()) {
-        logger.warning('Failed to get device list');
-        return Result(UnknownOmemoError());
-      }
-
-      final deviceList = deviceMapRaw.get<List<int>>();
-      for (final id in deviceList) {
-        // We already have a session with that device
-        if (ratchetSessions.contains(id)) continue;
-
-        // Ignore requests for our own device.
-        if (toJid == ownJid && id == ownId) {
-          logger.finest('Attempted to request bundle for our own device $id, which is the current device. Skipping request...');
-          continue;
-        }
-
-        logger.finest('Retrieving bundle for $toJid:$id');
-        final bundle = await retrieveDeviceBundle(toJid, id);
-        if (bundle.isType<OmemoBundle>()) {
-          newSessions.add(bundle.get<OmemoBundle>());
-        } else {
-          logger.warning('Failed to retrieve bundle for $toJid:$id');
-        }
-      }
-    }
-    
-    return Result(newSessions);
-  }
-
-  /// Sends an empty Omemo message to [toJid].
-  ///
-  /// If [findNewSessions] is true, then
-  /// new devices will be looked for first before sending the message. This means that
-  /// the new sessions will be included in the empty Omemo message. If false, then no
-  /// new sessions will be looked for before encrypting.
-  ///
-  /// [calledFromCriticalSection] MUST NOT be used from outside the manager. If true, then
-  /// sendEmptyMessage will not attempt to enter the critical section guarding the
-  /// encryption and decryption. If false, then the critical section will be entered before
-  /// encryption and left after sending the message.
-  Future<void> sendEmptyMessage(JID toJid, {
-    bool findNewSessions = false,
-    @protected
-    bool calledFromCriticalSection = false,
-  }) async {
-    if (!calledFromCriticalSection) {
-      final completer = await _handlerEntry(toJid);
-      if (completer != null) {
-        await completer.future;
-      }
-    }
-
-    var newSessions = <OmemoBundle>[];
-    if (findNewSessions) {
-      final result = await _findNewSessions(toJid, <XMLNode>[]);
-      if (!result.isType<OmemoError>()) newSessions = result.get<List<OmemoBundle>>();
-    }
-
-    final empty = await _encryptChildren(
-      null,
-      [toJid.toString()],
-      toJid.toString(),
-      newSessions,
-    );
-
+  /// For usage with omemo_dart's OmemoManager.
+  Future<void> sendEmptyMessageImpl(EncryptionResult result, String toJid) async {
     await getAttributes().sendStanza(
       Stanza.message(
-        to: toJid.toString(),
+        to: toJid,
         type: 'chat',
         children: [
-          empty,
+          _buildEncryptedElement(
+            result,
+            toJid,
+            await _getDeviceId(),
+          ),
 
           // Add a storage hint in case this is a message
           // Taken from the example at
@@ -447,10 +282,28 @@ abstract class OmemoManager extends XmppManagerBase {
       awaitable: false,
       encrypted: true,
     );
+  }
 
-    if (!calledFromCriticalSection) {
-      await _handlerExit(toJid);
-    }
+  /// Send a heartbeat message to [jid].
+  Future<void> sendOmemoHeartbeat(String jid) async {
+    final om = await getOmemoManager();
+    await om.sendOmemoHeartbeat(jid);
+  }
+  
+  /// For usage with omemo_dart's OmemoManager
+  Future<List<int>?> fetchDeviceList(String jid) async {
+    final result = await getDeviceList(JID.fromString(jid));
+    if (result.isType<OmemoError>()) return null;
+
+    return result.get<List<int>>();
+  }
+
+  /// For usage with omemo_dart's OmemoManager
+  Future<OmemoBundle?> fetchDeviceBundle(String jid, int id) async {
+    final result = await retrieveDeviceBundle(JID.fromString(jid), id);
+    if (result.isType<OmemoError>()) return null;
+
+    return result.get<OmemoBundle>();
   }
   
   Future<StanzaHandlerData> _onOutgoingStanza(Stanza stanza, StanzaHandlerData state) async {
@@ -461,6 +314,7 @@ abstract class OmemoManager extends XmppManagerBase {
 
     if (stanza.to == null) {
       // We cannot encrypt in this case.
+      logger.finest('Not encrypting since stanza.to is null');
       return state;
     }
 
@@ -471,34 +325,7 @@ abstract class OmemoManager extends XmppManagerBase {
     } else {
       logger.finest('shouldEncryptStanza returned true for message to $toJid.');
     }
-    
-    final completer = await _handlerEntry(toJid);
-    if (completer != null) {
-      await completer.future;
-    }
 
-    final newSessions = List<OmemoBundle>.empty(growable: true);
-    // Try to find new sessions for [toJid].
-    final resultToJid = await _findNewSessions(toJid, stanza.children);
-    if (resultToJid.isType<List<OmemoBundle>>()) {
-      newSessions.addAll(resultToJid.get<List<OmemoBundle>>());
-    } else {
-      if (resultToJid.isType<OmemoNotSupportedForContactException>()) {
-        await _handlerExit(toJid);
-        return state.copyWith(
-          cancel: true,
-          cancelReason: resultToJid.get<OmemoNotSupportedForContactException>(),
-        );
-      }
-    }
-
-    // Try to find new sessions for our own Jid.
-    final ownJid = getAttributes().getFullJID().toBare();
-    final resultOwnJid = await _findNewSessions(ownJid, stanza.children);
-    if (resultOwnJid.isType<List<OmemoBundle>>()) {
-      newSessions.addAll(resultOwnJid.get<List<OmemoBundle>>());
-    }
-    
     final toEncrypt = List<XMLNode>.empty(growable: true);
     final children = List<XMLNode>.empty(growable: true);
     for (final child in stanza.children) {
@@ -508,76 +335,40 @@ abstract class OmemoManager extends XmppManagerBase {
         toEncrypt.add(child);
       }
     }
+    
+    logger.finest('Beginning encryption');
+    final om = await getOmemoManager();
+    final result = await om.onOutgoingStanza(
+      OmemoOutgoingStanza(
+        [toJid.toString()],
+        _buildEnvelope(toEncrypt, toJid.toString()),
+      ),
+    );
+    logger.finest('Encryption done');
 
-    final jidsToEncryptFor = <String>[JID.fromString(stanza.to!).toBare().toString()];
-    // Prevent encrypting to self if there is only one device (ours).
-    if (await _hasSessionWith(ownJid.toString())) {
-      jidsToEncryptFor.add(ownJid.toString());
+    final encrypted = _buildEncryptedElement(
+      result,
+      toJid.toString(),
+      await _getDeviceId(),
+    );
+    children.add(encrypted);
+    
+    // Only add message specific metadata when actually sending a message
+    if (stanza.tag == 'message') {
+      children
+        // Add EME data
+        ..add(buildEmeElement(ExplicitEncryptionType.omemo2))
+        // Add a storage hint in case this is a message
+        // Taken from the example at
+        // https://xmpp.org/extensions/xep-0384.html#message-structure-description.
+        ..add(MessageProcessingHint.store.toXml());
     }
-
-    try {
-      logger.finest('Encrypting stanza');
-      final encrypted = await _encryptChildren(
-        toEncrypt,
-        jidsToEncryptFor,
-        stanza.to!,
-        newSessions,
-      );
-      logger.finest('Encryption done');
-
-      children.add(encrypted);
-
-      // Only add EME when sending a message
-      if (stanza.tag == 'message') {
-        children.add(buildEmeElement(ExplicitEncryptionType.omemo2));
-      }
-
-      // Add a storage hint in case this is a message
-      // Taken from the example at
-      // https://xmpp.org/extensions/xep-0384.html#message-structure-description.
-      if (stanza.tag == 'message') {
-        children.add(MessageProcessingHint.store.toXml());
-      }
-      
-      await _handlerExit(toJid);
-      return state.copyWith(
-        stanza: state.stanza.copyWith(
-          children: children,
-        ),
-        encrypted: true,
-      );
-    } catch (ex) {
-      logger.severe('Encryption failed! $ex');
-      await _handlerExit(toJid);
-      return state.copyWith(
-        cancel: true,
-        cancelReason: EncryptionFailedException(),
-        other: {
-          ...state.other,
-          'encryption_error': ex,
-        },
-      );
-    }
-  }
-
-  /// This function returns true if the encryption scheme should ignore unacked ratchets
-  /// and don't try to build a new ratchet even though there are unacked ones.
-  /// The current logic is that chat states with no body ignore the "ack" state of the
-  /// ratchets.
-  ///
-  /// This function may be overriden. By default, the ack status of the ratchet is ignored
-  /// if we're sending a message containing chatstates or chat markers and the message does
-  /// not contain a <body /> element.
-  @visibleForOverriding
-  bool shouldIgnoreUnackedRatchets(List<XMLNode> children) {
-    return listContains(
-      children,
-      (XMLNode child) {
-        return child.attributes['xmlns'] == chatStateXmlns || child.attributes['xmlns'] == chatMarkersXmlns;
-      },
-    ) && !listContains(
-      children,
-      (XMLNode child) => child.tag == 'body',
+    
+    return state.copyWith(
+      stanza: state.stanza.copyWith(
+        children: children,
+      ),
+      encrypted: true,
     );
   }
 
@@ -587,48 +378,12 @@ abstract class OmemoManager extends XmppManagerBase {
   @visibleForOverriding
   Future<bool> shouldEncryptStanza(JID toJid, Stanza stanza);
   
-  /// Wrapper function that attempts to enter the encryption/decryption critical section.
-  /// In case the critical section could be entered, null is returned. If not, then a
-  /// Completer is returned whose future will resolve once the critical section can be
-  /// entered.
-  Future<Completer<void>?> _handlerEntry(JID fromJid) async {
-    return _handlerLock.synchronized(() {
-      if (_handlerFutures.containsKey(fromJid)) {
-        final c = Completer<void>();
-        _handlerFutures[fromJid]!.addLast(c);
-        return c;
-      }
-
-      _handlerFutures[fromJid] = Queue();
-      return null;
-    });
-  }
-
-  /// Wrapper function that exits the critical section.
-  Future<void> _handlerExit(JID fromJid) async {
-    await _handlerLock.synchronized(() {
-      if (_handlerFutures.containsKey(fromJid)) {
-        if (_handlerFutures[fromJid]!.isEmpty) {
-          _handlerFutures.remove(fromJid);
-          return;
-        }
-
-        _handlerFutures[fromJid]!.removeFirst().complete();
-      }
-    });
-  }
-  
   Future<StanzaHandlerData> _onIncomingStanza(Stanza stanza, StanzaHandlerData state) async {
     final encrypted = stanza.firstTag('encrypted', xmlns: omemoXmlns);
     if (encrypted == null) return state;
     if (stanza.from == null) return state;
 
     final fromJid = JID.fromString(stanza.from!).toBare();
-    final completer = await _handlerEntry(fromJid);
-    if (completer != null) {
-      await completer.future;
-    }
-    
     final header = encrypted.firstTag('header')!;
     final payloadElement = encrypted.firstTag('payload');
     final keys = List<EncryptedKey>.empty(growable: true);
@@ -649,118 +404,49 @@ abstract class OmemoManager extends XmppManagerBase {
     final ourJid = getAttributes().getFullJID();
     final sid = int.parse(header.attributes['sid']! as String);
 
-    // Ensure that if we receive a message from a device that we don't know about, we
-    // ensure that _deviceMap is up-to-date.
-    final devices = _deviceMap[fromJid] ?? <int>[];
-    if (!devices.contains(sid)) {
-      await getDeviceList(fromJid);
-    }
-
-    String? decrypted;
-    try {
-      decrypted = await _decryptMessage(
-        payloadElement != null ? base64.decode(payloadElement.innerText()) : null,
+    final om = await getOmemoManager();
+    final result = await om.onIncomingStanza(
+      OmemoIncomingStanza(
         fromJid.toString(),
         sid,
-        keys,
         state.delayedDelivery?.timestamp.millisecondsSinceEpoch ?? DateTime.now().millisecondsSinceEpoch,
-      );
-    } catch (ex) {
-      logger.warning('Error occurred during message decryption: $ex');
+        keys,
+        payloadElement?.innerText(),
+      ),
+    );
 
-      await _handlerExit(fromJid);
-      return state.copyWith(
-        other: {
-          ...state.other,
-          'encryption_error': ex,
-        },
-      );
+    final children = stanza.children.where(
+      (child) => child.tag != 'encrypted' || child.attributes['xmlns'] != omemoXmlns,
+    ).toList();
+    final other = Map<String, dynamic>.from(state.other);
+    if (result.error != null) {
+      other['encryption_error'] = result.error;
     }
-    
-    final isAcked = await _isRatchetAcknowledged(fromJid.toString(), sid);
-    if (!isAcked) {
-      // Unacked ratchet decrypted this message
-      if (decrypted != null) {
-        // The message is not empty, i.e. contains content
-        logger.finest('Received non-empty OMEMO encrypted message for unacked ratchet. Acking with empty OMEMO message.');
 
-        await _ackRatchet(fromJid.toString(), sid);
-        await sendEmptyMessage(fromJid, calledFromCriticalSection: true);
+    if (result.payload != null) {
+      final envelope = XMLNode.fromString(result.payload!);
+      children.addAll(
+        envelope.firstTag('content')!.children,
+      );
 
-        final envelope = XMLNode.fromString(decrypted);
-        final children = stanza.children.where(
-          (child) => child.tag != 'encrypted' || child.attributes['xmlns'] != omemoXmlns,
-        ).toList()
-          ..addAll(envelope.firstTag('content')!.children);
-
-        final other = Map<String, dynamic>.from(state.other);
-        if (!checkAffixElements(envelope, stanza.from!, ourJid)) {
-          other['encryption_error'] = InvalidAffixElementsException();
-        }
-
-        await _handlerExit(fromJid);
-        return state.copyWith(
-          encrypted: true,
-          stanza: Stanza(
-            to: stanza.to,
-            from: stanza.from,
-            id: stanza.id,
-            type: stanza.type,
-            children: children,
-            tag: stanza.tag,
-            attributes: Map<String, String>.from(stanza.attributes),
-          ),
-          other: other,
-        );
-      } else {
-        logger.info('Received empty OMEMO message for unacked ratchet. Marking $fromJid:$sid as acked');
-        await _ackRatchet(fromJid.toString(), sid);
-
-        final ownId = await (await getSessionManager()).getDeviceId();
-        final kex = keys.any((key) => key.kex && key.rid == ownId);
-        if (kex) {
-          logger.info('Empty OMEMO message contained a kex. Answering.');
-          await sendEmptyMessage(fromJid, calledFromCriticalSection: true);
-        }
-
-        await _handlerExit(fromJid);
-        return state;
-      }
-    } else {
-      // The ratchet that decrypted the message was acked
-      if (decrypted != null) {
-        final envelope = XMLNode.fromString(decrypted);
-
-        final children = stanza.children.where(
-          (child) => child.tag != 'encrypted' || child.attributes['xmlns'] != omemoXmlns,
-        ).toList()
-          ..addAll(envelope.firstTag('content')!.children);
-
-        final other = Map<String, dynamic>.from(state.other);
-        if (!checkAffixElements(envelope, stanza.from!, ourJid)) {
-          other['encryption_error'] = InvalidAffixElementsException();
-        }
-        
-        await _handlerExit(fromJid);
-        return state.copyWith(
-          encrypted: true,
-          stanza: Stanza(
-            to: stanza.to,
-            from: stanza.from,
-            id: stanza.id,
-            type: stanza.type,
-            children: children,
-            tag: stanza.tag,
-            attributes: Map<String, String>.from(stanza.attributes),
-          ),
-          other: other,
-        );
-      } else {
-        logger.info('Received empty OMEMO message on acked ratchet. Doing nothing');
-        await _handlerExit(fromJid);
-        return state;
+      if (!checkAffixElements(envelope, stanza.from!, ourJid)) {
+        other['encryption_error'] = InvalidAffixElementsException();
       }
     }
+
+    return state.copyWith(
+      encrypted: true,
+      stanza: Stanza(
+        to: stanza.to,
+        from: stanza.from,
+        id: stanza.id,
+        type: stanza.type,
+        children: children,
+        tag: stanza.tag,
+        attributes: Map<String, String>.from(stanza.attributes),
+      ),
+      other: other,
+    );
   }
 
   /// Convenience function that attempts to retrieve the raw XML payload from the
@@ -776,15 +462,12 @@ abstract class OmemoManager extends XmppManagerBase {
   
   /// Retrieves the OMEMO device list from [jid].
   Future<Result<OmemoError, List<int>>> getDeviceList(JID jid) async {
-    if (_deviceMap.containsKey(jid)) return Result(_deviceMap[jid]);
-
     final itemsRaw = await _retrieveDeviceListPayload(jid);
     if (itemsRaw.isType<OmemoError>()) return Result(UnknownOmemoError());
 
     final ids = itemsRaw.get<XMLNode>().children
       .map((child) => int.parse(child.attributes['id']! as String))
       .toList();
-    _deviceMap[jid] = ids;
     return Result(ids);
   }
 
@@ -882,13 +565,9 @@ abstract class OmemoManager extends XmppManagerBase {
   }
 
   /// Subscribes to the device list PubSub node of [jid].
-  Future<void> subscribeToDeviceList(JID jid) async {
+  Future<void> subscribeToDeviceListImpl(String jid) async {
     final pm = getAttributes().getManagerById<PubSubManager>(pubsubManager)!;
-    final result = await pm.subscribe(jid.toString(), omemoDevicesXmlns);
-
-    if (!result.isType<PubSubError>()) {
-      _subscriptionMap[jid] = true;
-    }
+    await pm.subscribe(jid, omemoDevicesXmlns);
   }
 
   /// Attempts to find out if [jid] supports omemo:2.

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,
+      ),
+    );
+  }
+}

packages/moxxmpp/lib/src/xeps/xep_0444.dart

@@ -0,0 +1,68 @@
+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';
+import 'package:moxxmpp/src/stringxml.dart';
+
+class MessageReactions {
+  const MessageReactions(this.messageId, this.emojis);
+  final String messageId;
+  final List<String> emojis;
+
+  XMLNode toXml() {
+    return XMLNode.xmlns(
+      tag: 'reactions',
+      xmlns: messageReactionsXmlns,
+      attributes: <String, String>{
+        'id': messageId,
+      },
+      children: emojis.map((emoji) {
+        return XMLNode(
+          tag: 'reaction',
+          text: emoji,
+        );
+      }).toList(),
+    );
+  }
+}
+
+class MessageReactionsManager extends XmppManagerBase {
+  @override
+  List<String> getDiscoFeatures() => [ messageReactionsXmlns ];
+
+  @override
+  String getName() => 'MessageReactionsManager';
+
+  @override
+  String getId() => messageReactionsManager;
+
+  @override
+  List<StanzaHandler> getIncomingStanzaHandlers() => [
+    StanzaHandler(
+      stanzaTag: 'message',
+      tagName: 'reactions',
+      tagXmlns: messageReactionsXmlns,
+      callback: _onReactionsReceived,
+      // Before the message handler
+      priority: -99,
+    ),
+  ];
+
+  @override
+  Future<bool> isSupported() async => true;
+ 
+  Future<StanzaHandlerData> _onReactionsReceived(Stanza message, StanzaHandlerData state) async {
+    final reactionsElement = message.firstTag('reactions', xmlns: messageReactionsXmlns)!;
+    return state.copyWith(
+      messageReactions: MessageReactions(
+        reactionsElement.attributes['id']! as String,
+        reactionsElement.children
+          .where((c) => c.tag == 'reaction')
+          .map((c) => c.innerText())
+          .toList(),
+      ),
+    );
+  }
+}

packages/moxxmpp/lib/src/xeps/xep_0446.dart

@@ -4,7 +4,6 @@ import 'package:moxxmpp/src/xeps/staging/extensible_file_thumbnails.dart';
 import 'package:moxxmpp/src/xeps/xep_0300.dart';
 
 class FileMetadataData {
-
   const FileMetadataData({
     this.mediaType,
     this.width,

packages/moxxmpp/lib/src/xeps/xep_0447.dart

@@ -18,7 +18,6 @@ abstract class StatelessFileSharingSource {
 
 /// Implementation for url-data source elements.
 class StatelessFileSharingUrlSource extends StatelessFileSharingSource {
-
   StatelessFileSharingUrlSource(this.url);
 
   factory StatelessFileSharingUrlSource.fromXml(XMLNode element) {
@@ -41,8 +40,29 @@ class StatelessFileSharingUrlSource extends StatelessFileSharingSource {
   }
 }
 
-class StatelessFileSharingData {
+/// Finds the <sources/> element in [node] and returns the list of
+/// StatelessFileSharingSources contained with it.
+/// If [checkXmlns] is true, then the sources element must also have an xmlns attribute
+/// of "urn:xmpp:sfs:0".
+List<StatelessFileSharingSource> processStatelessFileSharingSources(XMLNode node, { bool checkXmlns = true }) {
+  final sources = List<StatelessFileSharingSource>.empty(growable: true);
+  
+  final sourcesElement = node.firstTag(
+    'sources',
+    xmlns: checkXmlns ? sfsXmlns : null,
+  )!;
+  for (final source in sourcesElement.children) {
+    if (source.attributes['xmlns'] == urlDataXmlns) {
+      sources.add(StatelessFileSharingUrlSource.fromXml(source));
+    } else if (source.attributes['xmlns'] == sfsEncryptionXmlns) {
+      sources.add(StatelessFileSharingEncryptedSource.fromXml(source));
+    }
+  }
 
+  return sources;
+}
+
+class StatelessFileSharingData {
   const StatelessFileSharingData(this.metadata, this.sources);
 
   /// Parse [node] as a StatelessFileSharingData element.
@@ -50,20 +70,10 @@ class StatelessFileSharingData {
     assert(node.attributes['xmlns'] == sfsXmlns, 'Invalid element xmlns');
     assert(node.tag == 'file-sharing', 'Invalid element name');
 
-    final sources = List<StatelessFileSharingSource>.empty(growable: true);
-    
-    final sourcesElement = node.firstTag('sources')!;
-    for (final source in sourcesElement.children) {
-      if (source.attributes['xmlns'] == urlDataXmlns) {
-        sources.add(StatelessFileSharingUrlSource.fromXml(source));
-      } else if (source.attributes['xmlns'] == sfsEncryptionXmlns) {
-        sources.add(StatelessFileSharingEncryptedSource.fromXml(source));
-      }
-    }
-
     return StatelessFileSharingData(
       FileMetadataData.fromXML(node.firstTag('file')!),
-      sources,
+      // TODO(PapaTutuWawa): This is a work around for Stickers where the source element has a XMLNS but SFS does not have one.
+      processStatelessFileSharingSources(node, checkXmlns: false),
     );
   }
 
@@ -120,7 +130,7 @@ class SFSManager extends XmppManagerBase {
     final sfs = message.firstTag('file-sharing', xmlns: sfsXmlns)!;
 
     return state.copyWith(
-      sfs: StatelessFileSharingData.fromXML(sfs),
+      sfs: StatelessFileSharingData.fromXML(sfs, ),
     );
   }
 }

packages/moxxmpp/lib/src/xeps/xep_0449.dart

@@ -0,0 +1,308 @@
+import 'dart:convert';
+import 'package:moxxmpp/src/jid.dart';
+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/rfcs/rfc_4790.dart';
+import 'package:moxxmpp/src/stanza.dart';
+import 'package:moxxmpp/src/stringxml.dart';
+import 'package:moxxmpp/src/types/result.dart';
+import 'package:moxxmpp/src/xeps/xep_0060/errors.dart';
+import 'package:moxxmpp/src/xeps/xep_0060/xep_0060.dart';
+import 'package:moxxmpp/src/xeps/xep_0300.dart';
+import 'package:moxxmpp/src/xeps/xep_0446.dart';
+import 'package:moxxmpp/src/xeps/xep_0447.dart';
+
+class Sticker {
+  const Sticker(this.metadata, this.sources, this.suggests);
+
+  factory Sticker.fromXML(XMLNode node) {
+    assert(node.tag == 'item', 'sticker has wrong tag');
+
+    return Sticker(
+      FileMetadataData.fromXML(node.firstTag('file', xmlns: fileMetadataXmlns)!),
+      processStatelessFileSharingSources(node, checkXmlns: false),
+      {},
+    );
+  }
+
+  final FileMetadataData metadata;
+  final List<StatelessFileSharingSource> sources;
+  // Language -> suggestion
+  final Map<String, String> suggests; 
+
+  XMLNode toPubSubXML() {
+    final suggestsElements = suggests.keys.map((suggest) {
+      Map<String, String> attrs;
+      if (suggest.isEmpty) {
+        attrs = {};
+      } else {
+        attrs = {
+          'xml:lang': suggest,
+        };
+      }
+
+      return XMLNode(
+        tag: 'suggest',
+        attributes: attrs,
+        text: suggests[suggest],
+      );
+    });
+
+    return XMLNode(
+      tag: 'item',
+      children: [
+        metadata.toXML(),
+        ...sources.map((source) => source.toXml()),
+        ...suggestsElements,
+      ],
+    );
+  }
+}
+
+class StickerPack {
+  const StickerPack(
+    this.id,
+    this.name,
+    this.summary,
+    this.hashAlgorithm,
+    this.hashValue,
+    this.stickers,
+    this.restricted,
+  );
+
+  factory StickerPack.fromXML(String id, XMLNode node, { bool hashAvailable = true }) {
+    assert(node.tag == 'pack', 'node has wrong tag');
+    assert(node.attributes['xmlns'] == stickersXmlns, 'node has wrong XMLNS');
+
+    var hashAlgorithm = HashFunction.sha256;
+    var hashValue = '';
+    if (hashAvailable) {
+      final hash = node.firstTag('hash', xmlns: hashXmlns)!;
+      hashAlgorithm = hashFunctionFromName(hash.attributes['algo']! as String);
+      hashValue = hash.innerText();
+    }
+    
+    return StickerPack(
+      id,
+      node.firstTag('name')!.innerText(),
+      node.firstTag('summary')!.innerText(),
+      hashAlgorithm,
+      hashValue,
+      node.children
+        .where((e) => e.tag == 'item')
+        .map<Sticker>(Sticker.fromXML)
+        .toList(),
+      node.firstTag('restricted') != null,
+    );
+  }
+
+  final String id;
+  // TODO(PapaTutuWawa): Turn name and summary into a Map as it may contain a xml:lang
+  final String name;
+  final String summary;
+  final HashFunction hashAlgorithm;
+  final String hashValue;
+  final List<Sticker> stickers;
+  final bool restricted;
+
+  /// When using the fromXML factory to parse a description of a sticker pack with a
+  /// yet unknown hash, then this function can be used in order to apply the freshly
+  /// calculated hash to the object.
+  StickerPack copyWithId(HashFunction newHashFunction, String newId) {
+    return StickerPack(
+      newId,
+      name,
+      summary,
+      newHashFunction,
+      newId,
+      stickers,
+      restricted,
+    );
+  }
+  
+  XMLNode toXML() {
+    return XMLNode.xmlns(
+      tag: 'pack',
+      xmlns: stickersXmlns,
+      children: [
+        // Pack metadata
+        XMLNode(
+          tag: 'name',
+          text: name,
+        ),
+        XMLNode(
+          tag: 'summary',
+          text: summary,
+        ),
+        constructHashElement(
+          hashAlgorithm.toName(),
+          hashValue,
+        ),
+
+        ...restricted ?
+          [XMLNode(tag: 'restricted')] :
+          [],
+        
+        // Stickers
+        ...stickers
+          .map((sticker) => sticker.toPubSubXML()),
+      ],
+    );
+  }
+
+  /// Calculates the sticker pack's hash as specified by XEP-0449.
+  Future<String> getHash(HashFunction hashFunction) async {
+    // Build the meta string
+    final metaTmp = [
+      <int>[
+        ...utf8.encode('name'),
+        0x1f,
+        0x1f,
+        ...utf8.encode(name),
+        0x1f,
+        0x1e,
+      ],
+      <int>[
+        ...utf8.encode('summary'),
+        0x1f,
+        0x1f,
+        ...utf8.encode(summary),
+        0x1f,
+        0x1e,
+      ],
+    ]..sort(ioctetSortComparatorRaw);
+    final metaString = List<int>.empty(growable: true);
+    for (final m in metaTmp) {
+      metaString.addAll(m);
+    }
+    metaString.add(0x1c);
+
+    // Build item hashes
+    final items = List<List<int>>.empty(growable: true);
+    for (final sticker in stickers) {
+      final tmp = List<int>.empty(growable: true)
+        ..addAll(utf8.encode(sticker.metadata.desc!))
+        ..add(0x1e);
+
+      final hashes = List<List<int>>.empty(growable: true);
+      for (final hash in sticker.metadata.hashes.keys) {
+        hashes.add([
+          ...utf8.encode(hash),
+          0x1f,
+          ...utf8.encode(sticker.metadata.hashes[hash]!),
+          0x1f,
+          0x1e,
+        ]);
+      }
+      hashes.sort(ioctetSortComparatorRaw);
+
+      for (final hash in hashes) {
+        tmp.addAll(hash);
+      }
+      tmp.add(0x1d);
+      items.add(tmp);
+    }
+    items.sort(ioctetSortComparatorRaw);
+    final stickersString = List<int>.empty(growable: true);
+    for (final item in items) {
+      stickersString.addAll(item);
+    }
+    stickersString.add(0x1c);
+
+    // Calculate the hash
+    final rawHash = await CryptographicHashManager.hashFromData(
+      [
+        ...metaString,
+        ...stickersString,
+      ],
+      hashFunction,
+    );
+    return base64.encode(rawHash).substring(0, 24);
+  }
+}
+
+class StickersManager extends XmppManagerBase {
+  @override
+  String getId() => stickersManager;
+
+  @override
+  String getName() => 'StickersManager';
+
+  @override
+  Future<bool> isSupported() async => true;
+
+  @override
+  List<StanzaHandler> getIncomingStanzaHandlers() => [
+    StanzaHandler(
+      stanzaTag: 'message',
+      tagXmlns: stickersXmlns,
+      tagName: 'sticker',
+      callback: _onIncomingMessage,
+      priority: -99,
+    ),
+  ];
+
+  Future<StanzaHandlerData> _onIncomingMessage(Stanza stanza, StanzaHandlerData state) async {
+    final sticker = stanza.firstTag('sticker', xmlns: stickersXmlns)!;
+    return state.copyWith(
+      stickerPackId: sticker.attributes['pack']! as String,
+    );
+  }
+
+  /// Publishes the StickerPack [pack] to the PubSub node of [jid].
+  ///
+  /// On success, returns true. On failure, returns a PubSubError.
+  Future<Result<PubSubError, bool>> publishStickerPack(JID jid, StickerPack pack) async {
+    assert(pack.id != '', 'The sticker pack must have an id');
+    final pm = getAttributes().getManagerById<PubSubManager>(pubsubManager)!;
+
+    return pm.publish(
+      jid.toBare().toString(),
+      stickersXmlns,
+      pack.toXML(),
+      id: pack.id,
+      options: const PubSubPublishOptions(
+        maxItems: 'max',
+      ),
+    );
+  }
+
+  /// Removes the sticker pack with id [id] from the PubSub node of [jid].
+  ///
+  /// On success, returns the true. On failure, returns a PubSubError.
+  Future<Result<PubSubError, bool>> retractStickerPack(JID jid, String id) async {
+    final pm = getAttributes().getManagerById<PubSubManager>(pubsubManager)!;
+
+    return pm.retract(
+      jid,
+      stickersXmlns,
+      id,
+    );
+  }
+
+  /// Fetches the sticker pack with id [id] from [jid].
+  ///
+  /// On success, returns the StickerPack. On failure, returns a PubSubError.
+  Future<Result<PubSubError, StickerPack>> fetchStickerPack(JID jid, String id) async {
+    final pm = getAttributes().getManagerById<PubSubManager>(pubsubManager)!;
+    final stickerPackDataRaw = await pm.getItem(
+      jid.toBare().toString(),
+      stickersXmlns,
+      id,
+    );
+    if (stickerPackDataRaw.isType<PubSubError>()) {
+      return Result(stickerPackDataRaw.get<PubSubError>());
+    }
+
+    final stickerPackData = stickerPackDataRaw.get<PubSubItem>();
+    final stickerPack = StickerPack.fromXML(
+      stickerPackData.id,
+      stickerPackData.payload,
+    );
+
+    return Result(stickerPack);
+  }
+}

packages/moxxmpp/pubspec.yaml

@@ -1,6 +1,6 @@
 name: moxxmpp
 description: A pure-Dart XMPP library
-version: 0.1.3+1
+version: 0.1.6+1
 homepage: https://codeberg.org/moxxy/moxxmpp
 publish_to: https://git.polynom.me/api/packages/Moxxy/pub
 
@@ -19,8 +19,8 @@ dependencies:
    hosted: https://git.polynom.me/api/packages/Moxxy/pub
    version: ^0.1.5
   omemo_dart:
-   hosted: https://git.polynom.me/api/packages/PapaTutuWawa/pub
-   version: ^0.3.2
+    hosted: https://git.polynom.me/api/packages/PapaTutuWawa/pub
+    version: ^0.4.0
   random_string: ^2.3.1
   saslprep: ^1.0.2
   synchronized: ^3.0.0+2
@@ -31,6 +31,6 @@ dev_dependencies:
   build_runner: ^2.1.11
   moxxmpp_socket_tcp:
    hosted: https://git.polynom.me/api/packages/Moxxy/pub
-   version: ^0.1.2+5
+   version: ^0.1.2+9
   test: ^1.16.0
   very_good_analysis: ^3.0.1

packages/moxxmpp_socket_tcp/CHANGELOG.md

@@ -1,3 +1,19 @@
+## 0.1.2+9
+
+ - Update a dependency to the latest release.
+
+## 0.1.2+8
+
+ - Update a dependency to the latest release.
+
+## 0.1.2+7
+
+ - Update a dependency to the latest release.
+
+## 0.1.2+6
+
+ - Update a dependency to the latest release.
+
 ## 0.1.2+5
 
  - Update a dependency to the latest release.

packages/moxxmpp_socket_tcp/README.md

@@ -14,3 +14,9 @@ is, for example, [moxdns](https://codeberg.org/moxxy/moxdns).
 ## License
 
 See `./LICENSE`.
+
+## Support
+
+If you like what I do and you want to support me, feel free to donate to me on Ko-Fi.
+
+[<img src="https://codeberg.org/moxxy/moxxyv2/raw/branch/master/assets/repo/kofi.png" height="36" style="height: 36px; border: 0px;"></img>](https://ko-fi.com/papatutuwawa)

packages/moxxmpp_socket_tcp/pubspec.yaml

@@ -1,6 +1,6 @@
 name: moxxmpp_socket_tcp
 description: A socket for moxxmpp using TCP that implements the RFC6120 connection algorithm and XEP-0368
-version: 0.1.2+5
+version: 0.1.2+9
 homepage: https://codeberg.org/moxxy/moxxmpp
 publish_to: https://git.polynom.me/api/packages/Moxxy/pub
 
@@ -12,7 +12,7 @@ dependencies:
   meta: ^1.6.0
   moxxmpp:
     hosted: https://git.polynom.me/api/packages/Moxxy/pub
-    version: ^0.1.3+1
+    version: ^0.1.6+1
 
 dev_dependencies:
   lints: ^2.0.0