feat: finalize transport v2 migration (Phase C)

docs/architecture/TRANSPORT_V2_MIGRATION.md

@@ -18,10 +18,12 @@ during the migration window.
 > - **Reference client (CLI)**: `MostroP2P/mostro-cli` PRs #176, #177, #178 and
 >   its `docs/TRANSPORT_V2_SPEC.md`.
 >
-> **Status.** Living design specification. **Phase A (dual receive)** —
-> including `protocol_version` auto-detection and per-node transport resolution
-> on the receive path — is merged to `main`. **Phase B (dual send)** is
-> implemented in this branch. Phases C–D (§5) are pending.
+> **Status.** **Migration complete.** All phases (§5) are implemented and
+> merged: dual receive (A), dual send (B), per-node `protocol_version`
+> auto-detection and transport wiring (folded into A/B), the `version`-field
+> cleanup (C), and the test suite (D). The app speaks both transports and
+> selects per node; the v1 gift-wrap path is unchanged and the v2 NIP-44 path
+> engages automatically against a node advertising `protocol_version=2`.
 
 ---
 
@@ -231,16 +233,14 @@ this is the version-skew guard. The downgrade must be **logged explicitly** (at
 `warn`) so a misconfigured or unreachable node cannot silently leave the app in
 a degraded transport without anyone noticing.
 
-### 4.2 `version` field stops being a global constant
+### 4.2 `version` field is derived from the transport
 
-`Config.mostroVersion` is currently a hardcoded `1`
-(`lib/core/config.dart:56`) read by `MostroMessage.toJson()`
-(`lib/data/models/mostro_message.dart:30`). The message `version` must instead
-be **derived from the resolved `Transport`** (1 for `giftWrap`, 2 for `nip44` —
-decision #2). The cleanest seam is to pass the `Transport` (not a raw int) into
-the serialize/wrap path rather than reading a global, so the version number is
-always a function of the transport and a single `MostroMessage` can be wrapped
-for either transport without the two drifting apart.
+The global `Config.mostroVersion` constant has been **removed**. The message
+`version` is now a function of the wire transport: `MostroMessage.toJson({int?
+version})` defaults to `1` (gift wrap — used by storage, logging and the v1 send
+path), and `wrapNip44` passes `version: 2` explicitly. The same serialized
+message JSON is reused for the tuple, the trade signature and the identity-proof
+payload, so element 0, element 1 and element 2 can never drift apart.
 
 ### 4.3 Touch points (current v1 code → where v2 plugs in)
 
@@ -256,7 +256,7 @@ for either transport without the two drifting apart.
 | Background receive decrypt (unWrap → `result[0]`) | `lib/features/notifications/services/background_notification_service.dart:199-322` |
 | NIP-59 unwrap | `lib/shared/utils/nostr_utils.dart:383-443` |
 | Node info / `protocol_version` parse | `lib/features/mostro/mostro_instance.dart:119-251` |
-| Global `version` constant | `lib/core/config.dart:56` |
+| `version` derived from transport (no global constant) | `lib/data/models/mostro_message.dart` (`toJson`) |
 
 ---
 
@@ -321,25 +321,35 @@ unchanged.
 - The NIP-40 `expiration` tag is **omitted** (the daemon treats it as optional /
   caller-supplied), avoiding any risk of a message expiring before processing.
 
-### Phase C — Send-side wiring
-
-> `protocol_version` parsing and per-node transport resolution already landed in
-> Phase A (receive). This phase only threads that same resolved transport into
-> the **send** path.
-
-- Thread the resolved `Transport` (§4.1) into `MostroService.publishOrder` so
-  outbound messages use the v2 `wrap` from Phase B against a v2 node, while v1
-  nodes keep the gift-wrap path.
-- Reuse the version-skew guard from Phase A: degrade to v1 on an unsupported /
-  unreachable node, keeping the existing explicit downgrade logging.
-
-### Phase D — Tests
-
-- v2 `wrap` → `unwrap` round-trip: produces a kind-14 event authored by the
-  trade key; decodes back to the same `MostroMessage`.
-- `protocol_version` tag parse → transport mapping (including absent → v1).
-- Identity proof: present in normal mode, `null` in full-privacy; domain string
-  is exactly `mostro-transport-v2-identity:<tradePubkey>:<messageJSON>`.
+### Phase C — Wiring & finalization ✅
+
+> Send-side transport wiring landed with Phase B: every outbound Mostro send
+> already routes through `MostroMessage.wrapForTransport(protocolVersion: …)`,
+> and receive-side detection landed with Phase A. This phase finalized the
+> remaining loose ends.
+
+- Removed the global `Config.mostroVersion`; the message `version` is derived
+  from the transport (§4.2).
+- Extracted the transport → orders-filter mapping into the testable top-level
+  `buildOrdersFilter` (`subscription_manager.dart`).
+- The version-skew guard (`resolveTransport`) degrades to v1 on an unsupported
+  protocol version and logs it (§4.1).
+
+### Phase D — Tests ✅
+
+- v2 `wrap` → `unwrap` round-trip, reputation and full-privacy
+  (`test/data/mostro_message_nip44_test.dart`): produces a kind-14 event
+  authored by the trade key and decodes back to the same message; cryptographically
+  verifies the trade signature and the identity proof, including the exact domain
+  string `mostro-transport-v2-identity:<tradePubkey>:<messageJSON>` (`null` in
+  full-privacy).
+- `protocol_version` tag parse → transport mapping, including absent → v1
+  (`test/features/mostro/transport_test.dart`,
+  `test/features/mostro/mostro_instance_test.dart`).
+- Orders subscription filter is transport-aware
+  (`test/features/subscriptions/orders_filter_test.dart`).
+- Restore decode handles both transports and yields identical results
+  (`test/features/restore/restore_decode_test.dart`).
 - Regression: the v1 gift-wrap path is byte-for-byte unchanged (existing
   serialization tests stay green).
 

lib/core/config.dart

@@ -52,9 +52,6 @@ class Config {
   // Debug mode
   static bool get isDebug => !kReleaseMode;
 
-  // Mostro version
-  static int mostroVersion = 1;
-
   // Key derivation configuration
   static const String keyDerivationPath = "m/44'/1237'/38383'/0";
 

lib/data/models/mostro_message.dart

@@ -3,7 +3,6 @@ import 'package:convert/convert.dart';
 import 'package:crypto/crypto.dart';
 import 'package:dart_nostr/nostr/core/key_pairs.dart';
 import 'package:dart_nostr/nostr/model/event/event.dart';
-import 'package:mostro_mobile/core/config.dart';
 import 'package:mostro_mobile/data/models/enums/action.dart';
 import 'package:mostro_mobile/data/models/payload.dart';
 import 'package:mostro_mobile/features/mostro/transport.dart';
@@ -28,7 +27,11 @@ class MostroMessage<T extends Payload> {
 
   Map<String, dynamic> toJson({int? version}) {
     Map<String, dynamic> json = {
-      'version': version ?? Config.mostroVersion,
+      // The message version is derived from the wire transport: 1 for gift wrap
+      // (the default here, used by storage/logging and the v1 send path) and 2
+      // for NIP-44 direct (passed explicitly by `wrapNip44`). See §4.2 of
+      // docs/architecture/TRANSPORT_V2_MIGRATION.md.
+      'version': version ?? 1,
       'request_id': requestId,
       'trade_index': tradeIndex,
     };

lib/features/settings/about_screen.dart

@@ -335,6 +335,14 @@ class AboutScreen extends ConsumerWidget {
             ),
             const SizedBox(height: 16),
 
+            _buildInfoRowWithDialog(
+              context,
+              S.of(context)!.protocolVersion,
+              instance.protocolVersion.toString(),
+              S.of(context)!.protocolVersionExplanation,
+            ),
+            const SizedBox(height: 16),
+
             _buildInfoRowWithDialog(
               context,
               S.of(context)!.mostroCommitId,

lib/features/subscriptions/subscription_manager.dart

@@ -1,5 +1,6 @@
 import 'dart:async';
 
+import 'package:flutter/foundation.dart';
 import 'package:dart_nostr/dart_nostr.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:mostro_mobile/services/logger_service.dart';
@@ -186,22 +187,11 @@ class SubscriptionManager {
         // and re-subscribe when the node info arrives after this subscription.
         final transport = _resolveOrdersTransport();
         _appliedOrdersTransport = transport;
-        switch (transport) {
-          case Transport.giftWrap:
-            return NostrFilter(
-              kinds: [1059],
-              p: tradeKeys,
-            );
-          case Transport.nip44:
-            // v2 Mostro replies are kind 14 authored by the node and addressed
-            // (p) to the trade key; the authors pin disambiguates them from
-            // NIP-17 peer chat, which is also kind 14 (§3.4).
-            return NostrFilter(
-              kinds: [14],
-              authors: [ref.read(settingsProvider).mostroPublicKey],
-              p: tradeKeys,
-            );
-        }
+        return buildOrdersFilter(
+          transport,
+          tradeKeys,
+          ref.read(settingsProvider).mostroPublicKey,
+        );
       case SubscriptionType.chat:
         if (sessions.isEmpty) {
           return null;
@@ -423,3 +413,33 @@ class SubscriptionManager {
     _relayListController.close();
   }
 }
+
+/// Builds the orders subscription filter for the resolved [transport] (§4.1).
+///
+/// - v1 ([Transport.giftWrap]): kind 1059 addressed (`p`) to the trade keys.
+/// - v2 ([Transport.nip44]): kind 14 authored by the node ([mostroPubkey]) and
+///   addressed to the trade keys — the `authors` pin disambiguates Mostro v2
+///   replies from NIP-17 peer chat, which is also kind 14 (§3.4).
+///
+/// Top-level so the transport → filter mapping can be unit-tested without the
+/// full [SubscriptionManager] / Riverpod orchestration.
+@visibleForTesting
+NostrFilter buildOrdersFilter(
+  Transport transport,
+  List<String> tradeKeys,
+  String mostroPubkey,
+) {
+  switch (transport) {
+    case Transport.giftWrap:
+      return NostrFilter(
+        kinds: [1059],
+        p: tradeKeys,
+      );
+    case Transport.nip44:
+      return NostrFilter(
+        kinds: [14],
+        authors: [mostroPubkey],
+        p: tradeKeys,
+      );
+  }
+}

lib/l10n/intl_de.arb

@@ -975,6 +975,8 @@
     "read": "Lesen",
     "technicalDetails": "Technische Details",
     "mostroDaemonVersion": "Mostro-Version",
+    "protocolVersion": "Protokollversion",
+    "protocolVersionExplanation": "Das Transportprotokoll dieses Knotens: 1 = NIP-59 Gift Wrap, 2 = NIP-44 Direktnachrichten. Die App erkennt dies automatisch und verwendet den passenden Transport.",
     "mostroCommitId": "Mostro Commit-ID",
     "orderExpiration": "Order-Ablaufzeit",
     "holdInvoiceExpiration": "Hold-Invoice Ablaufzeit",

lib/l10n/intl_en.arb

@@ -975,6 +975,8 @@
     "read": "Read",
     "technicalDetails": "Technical Details",
     "mostroDaemonVersion": "Mostro Version",
+    "protocolVersion": "Protocol Version",
+    "protocolVersionExplanation": "The wire transport protocol this node speaks: 1 = NIP-59 gift wrap, 2 = NIP-44 direct messages. The app detects this automatically and uses the matching transport.",
     "mostroCommitId": "Mostro Commit ID",
     "orderExpiration": "Order Expiration",
     "holdInvoiceExpiration": "Hold Invoice Expiration",

lib/l10n/intl_es.arb

@@ -952,6 +952,8 @@
     "read": "Leer",
     "technicalDetails": "Detalles Técnicos",
     "mostroDaemonVersion": "Versión de Mostro",
+    "protocolVersion": "Versión del Protocolo",
+    "protocolVersionExplanation": "El protocolo de transporte que habla este nodo: 1 = gift wrap NIP-59, 2 = mensajes directos NIP-44. La app lo detecta automáticamente y usa el transporte correspondiente.",
     "mostroCommitId": "ID de Commit Mostro",
     "orderExpiration": "Expiración de Orden",
     "holdInvoiceExpiration": "Expiración de Factura de Retención",

lib/l10n/intl_fr.arb

@@ -975,6 +975,8 @@
     "read": "Lire",
     "technicalDetails": "Détails techniques",
     "mostroDaemonVersion": "Version de Mostro",
+    "protocolVersion": "Version du Protocole",
+    "protocolVersionExplanation": "Le protocole de transport utilisé par ce nœud : 1 = gift wrap NIP-59, 2 = messages directs NIP-44. L'application le détecte automatiquement et utilise le transport correspondant.",
     "mostroCommitId": "ID de commit Mostro",
     "orderExpiration": "Expiration de commande",
     "holdInvoiceExpiration": "Expiration hold invoice",

lib/l10n/intl_it.arb

@@ -1014,6 +1014,8 @@
     "read": "Leggi",
     "technicalDetails": "Dettagli Tecnici",
     "mostroDaemonVersion": "Versione di Mostro",
+    "protocolVersion": "Versione del Protocollo",
+    "protocolVersionExplanation": "Il protocollo di trasporto utilizzato da questo nodo: 1 = gift wrap NIP-59, 2 = messaggi diretti NIP-44. L'app lo rileva automaticamente e usa il trasporto corrispondente.",
     "mostroCommitId": "ID Commit Mostro",
     "orderExpiration": "Scadenza Ordine",
     "holdInvoiceExpiration": "Scadenza Fattura di Blocco",

test/features/subscriptions/orders_filter_test.dart

@@ -0,0 +1,35 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:mostro_mobile/features/mostro/transport.dart';
+import 'package:mostro_mobile/features/subscriptions/subscription_manager.dart';
+
+void main() {
+  group('buildOrdersFilter (transport-aware orders subscription)', () {
+    final mostroPubkey = 'a' * 64;
+    final tradeKeys = ['b' * 64, 'c' * 64];
+
+    test('v1 (giftWrap) → kind 1059, no authors pin', () {
+      final filter = buildOrdersFilter(
+        Transport.giftWrap,
+        tradeKeys,
+        mostroPubkey,
+      );
+
+      expect(filter.kinds, [1059]);
+      expect(filter.p, tradeKeys);
+      expect(filter.authors, isNull);
+    });
+
+    test('v2 (nip44) → kind 14 authored by the node, addressed to trade keys',
+        () {
+      final filter = buildOrdersFilter(
+        Transport.nip44,
+        tradeKeys,
+        mostroPubkey,
+      );
+
+      expect(filter.kinds, [14]);
+      expect(filter.authors, [mostroPubkey]);
+      expect(filter.p, tradeKeys);
+    });
+  });
+}

test/services/mostro_service_test.dart

@@ -228,7 +228,7 @@ void main() {
 
       final messageContent = {
         'order': {
-          'version': Config.mostroVersion,
+          'version': 1,
           'id': orderId,
           'action': 'take-sell',
           'payload': {
@@ -289,7 +289,7 @@ void main() {
         userPubKey: userPubKey,
         messageContent: {
           'order': {
-            'version': Config.mostroVersion,
+            'version': 1,
             'id': orderId,
             'action': 'take-sell',
             'payload': {
@@ -349,7 +349,7 @@ void main() {
         userPubKey: userPubKey,
         messageContent: {
           'order': {
-            'version': Config.mostroVersion,
+            'version': 1,
             'id': orderId,
             'action': 'take-sell',
             'payload': {
@@ -407,7 +407,7 @@ void main() {
       // Simulate server-side verification
       final messageContent = {
         'order': {
-          'version': Config.mostroVersion,
+          'version': 1,
           'id': orderId,
           'action': 'take-sell',
           'payload': {