From 72704ddebbef048325e02d7bf1d5ead21a2c78fa Mon Sep 17 00:00:00 2001
From: lowrt <nineder197789@gmail.com>
Date: Wed, 9 Sep 2026 18:52:08 +0800
Subject: [PATCH 1/3] fix(eew): continue replay when historical RTS data is
 missing
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Fix(zh-Hant): 修正歷史 RTS 資料不存在時地震重播無法繼續
Fix(en-US): fix earthquake replay stopping when historical RTS data is unavailable
---
 lib/core/network/api_exception.dart                 | 12 +++++++++---
 lib/core/realtime/realtime_channel.dart             |  3 +++
 lib/core/realtime/realtime_source.dart              |  6 ++++++
 lib/features/earthquake/data/rts_replay_source.dart |  7 ++++++-
 4 files changed, 24 insertions(+), 4 deletions(-)

diff --git a/lib/core/network/api_exception.dart b/lib/core/network/api_exception.dart
index d46f47dfa..b6db943c0 100644
--- a/lib/core/network/api_exception.dart
+++ b/lib/core/network/api_exception.dart
@@ -10,15 +10,21 @@ import 'package:dpip/core/logging/log.dart';
 /// every repository method is a one-liner and none can accidentally forget the
 /// `try` or return `Ok` on failure — which for a safety feed would turn a dead
 /// source into a false all-clear.
-Future<Result<T>> guardResult<T>(Future<T> Function() body) async {
+Future<Result<T>> guardResult<T>(
+  Future<T> Function() body, {
+  bool Function(Failure failure)? shouldLog,
+}) async {
   try {
     return Ok(await body());
   } catch (error, stackTrace) {
     // Silent failures are the worst kind: the UI shows its error state and
     // nothing else records WHY. One line per failure, here at the single
     // choke point every repository passes through.
-    Log.handle(error, stackTrace, 'repository fetch/decode');
-    return Err(mapException(error));
+    final failure = mapException(error);
+    if (shouldLog?.call(failure) ?? true) {
+      Log.handle(error, stackTrace, 'repository fetch/decode');
+    }
+    return Err(failure);
   }
 }
 
diff --git a/lib/core/realtime/realtime_channel.dart b/lib/core/realtime/realtime_channel.dart
index 27c68c168..40864f6c3 100644
--- a/lib/core/realtime/realtime_channel.dart
+++ b/lib/core/realtime/realtime_channel.dart
@@ -234,6 +234,9 @@ class RealtimeChannel<T> implements RealtimeChannelBase {
           );
           if (changed) _publish();
         case Err(:final failure):
+          if (_source.isIgnorableFailure(failure)) {
+            return;
+          }
           final status = _classify();
           final changed = status != _current.status;
           _current = _current.copyWith(
diff --git a/lib/core/realtime/realtime_source.dart b/lib/core/realtime/realtime_source.dart
index 12a7710e2..9b17d30f0 100644
--- a/lib/core/realtime/realtime_source.dart
+++ b/lib/core/realtime/realtime_source.dart
@@ -1,5 +1,7 @@
 import 'package:dpip/core/error/result.dart';
 
+import '../error/failure.dart';
+
 /// The transport + freshness-reference seam a [RealtimeChannel] polls.
 ///
 /// One implementation per feed (EEW now, RTS later). Implementing this is the
@@ -23,6 +25,10 @@ abstract class RealtimeSource<T> {
   /// whose default `==` is identity (e.g. `List`).
   bool sameData(T? a, T? b) => identical(a, b) || a == b;
 
+  /// Returns true when a fetch failure means there is simply no data
+  /// for the requested point in time, rather than a realtime failure.
+  bool isIgnorableFailure(Failure failure) => false;
+
   /// Drops any transport the source is holding open while the app is in the
   /// background, where nothing is watching the feed.
   ///
diff --git a/lib/features/earthquake/data/rts_replay_source.dart b/lib/features/earthquake/data/rts_replay_source.dart
index d7f0687d2..55cc1202f 100644
--- a/lib/features/earthquake/data/rts_replay_source.dart
+++ b/lib/features/earthquake/data/rts_replay_source.dart
@@ -5,6 +5,8 @@ import 'package:dpip/core/realtime/replay_clock.dart';
 import 'package:dpip/features/earthquake/data/earthquake_api.dart';
 import 'package:dpip/features/earthquake/domain/rts.dart';
 
+import '../../../core/error/failure.dart';
+
 /// Replays the RTS feed at a fixed point in the past — a plain **polling**
 /// source (not SSE): each [fetch] asks [EarthquakeApi.getRtsAt] for the
 /// snapshot at the current second of [clock], which ticks 1:1 with real time
@@ -25,7 +27,10 @@ class RtsReplaySource extends RealtimeSource<Rts> {
     final seconds = clock.now().millisecondsSinceEpoch ~/ 1000;
     final json = await _api.getRtsAt(seconds);
     return Rts.fromJson(json as Map<String, dynamic>);
-  });
+  }, shouldLog: (failure) => failure is! NotFoundFailure);
+
+  @override
+  bool isIgnorableFailure(Failure failure) => failure is NotFoundFailure;
 
   /// Null: freshness is "did the last poll succeed", not payload age — the
   /// payload's own [Rts.time] is *intentionally* historical, so keying off it

From b47cad9d3efb45b8ebce91736fa7fc7399685351 Mon Sep 17 00:00:00 2001
From: PiscesXD <rclu2881@gmail.com>
Date: Thu, 10 Sep 2026 11:03:27 +0800
Subject: [PATCH 2/3] fix(eew): say an old replay is replaying, not
 disconnected
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Fix(zh-Hant): 重播較舊的地震時，狀態列不再寫「連線中斷」，改成「重播中」
Fix(en-US): replaying an older earthquake no longer reads "connection lost"
---
 lib/core/network/api_exception.dart           |  9 ++-
 lib/core/realtime/realtime_channel.dart       | 40 +++++++++++---
 lib/core/realtime/realtime_source.dart        | 19 +++++--
 .../earthquake/data/rts_replay_source.dart    | 11 +++-
 .../pages/report_replay_page.dart             | 18 ++++--
 .../presentation/rts_realtime_controller.dart |  9 +++
 lib/l10n/app_en.arb                           |  4 ++
 lib/l10n/app_fil.arb                          |  1 +
 lib/l10n/app_id.arb                           |  1 +
 lib/l10n/app_ja.arb                           |  1 +
 lib/l10n/app_ko.arb                           |  1 +
 lib/l10n/app_th.arb                           |  1 +
 lib/l10n/app_vi.arb                           |  1 +
 lib/l10n/app_yue.arb                          |  1 +
 lib/l10n/app_zh.arb                           |  1 +
 lib/l10n/app_zh_Hans.arb                      |  1 +
 lib/l10n/app_zh_Hant_HK.arb                   |  1 +
 lib/l10n/app_zh_TW.arb                        |  1 +
 lib/l10n/gen/app_localizations.dart           |  6 ++
 lib/l10n/gen/app_localizations_en.dart        |  3 +
 lib/l10n/gen/app_localizations_fil.dart       |  3 +
 lib/l10n/gen/app_localizations_id.dart        |  3 +
 lib/l10n/gen/app_localizations_ja.dart        |  3 +
 lib/l10n/gen/app_localizations_ko.dart        |  3 +
 lib/l10n/gen/app_localizations_th.dart        |  3 +
 lib/l10n/gen/app_localizations_vi.dart        |  3 +
 lib/l10n/gen/app_localizations_yue.dart       |  3 +
 lib/l10n/gen/app_localizations_zh.dart        | 12 ++++
 test/core/network/api_exception_test.dart     | 38 +++++++++++++
 test/core/realtime/realtime_channel_test.dart | 55 +++++++++++++++++++
 30 files changed, 233 insertions(+), 23 deletions(-)

diff --git a/lib/core/network/api_exception.dart b/lib/core/network/api_exception.dart
index b6db943c0..83ef63c80 100644
--- a/lib/core/network/api_exception.dart
+++ b/lib/core/network/api_exception.dart
@@ -10,6 +10,12 @@ import 'package:dpip/core/logging/log.dart';
 /// every repository method is a one-liner and none can accidentally forget the
 /// `try` or return `Ok` on failure — which for a safety feed would turn a dead
 /// source into a false all-clear.
+///
+/// [shouldLog] is the narrow exception to the logging below, for a caller whose
+/// failure is an expected shape rather than a fault — a replay polling past the
+/// end of a feed's retention, say, where the 404 arrives once a second for the
+/// whole session. It drops the log line only; the [Err] is returned either way,
+/// so no caller can mistake a suppressed log for a success.
 Future<Result<T>> guardResult<T>(
   Future<T> Function() body, {
   bool Function(Failure failure)? shouldLog,
@@ -19,7 +25,8 @@ Future<Result<T>> guardResult<T>(
   } catch (error, stackTrace) {
     // Silent failures are the worst kind: the UI shows its error state and
     // nothing else records WHY. One line per failure, here at the single
-    // choke point every repository passes through.
+    // choke point every repository passes through — unless the caller has
+    // said this particular failure is expected (see [shouldLog]).
     final failure = mapException(error);
     if (shouldLog?.call(failure) ?? true) {
       Log.handle(error, stackTrace, 'repository fetch/decode');
diff --git a/lib/core/realtime/realtime_channel.dart b/lib/core/realtime/realtime_channel.dart
index 40864f6c3..fabc938f3 100644
--- a/lib/core/realtime/realtime_channel.dart
+++ b/lib/core/realtime/realtime_channel.dart
@@ -224,6 +224,10 @@ class RealtimeChannel<T> implements RealtimeChannelBase {
           final status = _classify();
           final changed =
               status != _current.status ||
+              // A recovery is always worth telling: the state being replaced
+              // carries the reason the feed was empty, which the replay page
+              // shows even while the status word itself hasn't moved.
+              _current.lastFailure != null ||
               !_source.sameData(value, _current.data);
           _current = RealtimeState<T>(
             status: status,
@@ -234,20 +238,38 @@ class RealtimeChannel<T> implements RealtimeChannelBase {
           );
           if (changed) _publish();
         case Err(:final failure):
-          if (_source.isIgnorableFailure(failure)) {
-            return;
-          }
+          // "There is no data for that instant" is an answer, not a fault. It
+          // is still *recorded* — a replay page reads it to say "重播中" rather
+          // than "連線中斷" — but it is not counted and not logged: the poll
+          // runs at 1 Hz, so an old replay would otherwise file one crash
+          // report a second for its whole length.
+          //
+          // Freshness is untouched either way. The tick that preceded this
+          // fetch already aged the status (see [_onTick]), so an ignored
+          // failure still reaches stale and then offline on schedule — nothing
+          // here can hold a feed that is receiving nothing at `live`.
+          final ignorable = _source.isIgnorableFailure(failure);
           final status = _classify();
-          final changed = status != _current.status;
+          // A change of failure *kind* is published even when the status word
+          // hasn't moved, because that is what the replay page switches on.
+          // Repeats of one kind are not: at 1 Hz that would be a rebuild a
+          // second for the length of an outage.
+          final changed =
+              status != _current.status ||
+              _current.lastFailure.runtimeType != failure.runtimeType;
           _current = _current.copyWith(
             status: status,
             lastFailure: failure,
-            consecutiveFailures: _current.consecutiveFailures + 1,
-          );
-          Log.warning(
-            '[$_label] poll failed '
-            '(${_current.consecutiveFailures}×): ${failure.message}',
+            consecutiveFailures: ignorable
+                ? _current.consecutiveFailures
+                : _current.consecutiveFailures + 1,
           );
+          if (!ignorable) {
+            Log.warning(
+              '[$_label] poll failed '
+              '(${_current.consecutiveFailures}×): ${failure.message}',
+            );
+          }
           if (changed) _publish();
       }
     } catch (error, stackTrace) {
diff --git a/lib/core/realtime/realtime_source.dart b/lib/core/realtime/realtime_source.dart
index 9b17d30f0..707a104a3 100644
--- a/lib/core/realtime/realtime_source.dart
+++ b/lib/core/realtime/realtime_source.dart
@@ -1,7 +1,6 @@
+import 'package:dpip/core/error/failure.dart';
 import 'package:dpip/core/error/result.dart';
 
-import '../error/failure.dart';
-
 /// The transport + freshness-reference seam a [RealtimeChannel] polls.
 ///
 /// One implementation per feed (EEW now, RTS later). Implementing this is the
@@ -25,8 +24,20 @@ abstract class RealtimeSource<T> {
   /// whose default `==` is identity (e.g. `List`).
   bool sameData(T? a, T? b) => identical(a, b) || a == b;
 
-  /// Returns true when a fetch failure means there is simply no data
-  /// for the requested point in time, rather than a realtime failure.
+  /// Whether a fetch failure means there is simply no data for the requested
+  /// point in time, rather than a fault worth counting. The channel still
+  /// records it as `lastFailure` — that is what a replay page reads to say the
+  /// instant has no snapshot instead of calling itself disconnected — but does
+  /// not count it toward `consecutiveFailures` and does not log it.
+  ///
+  /// **A noise switch, not a liveness one.** Freshness is unaffected either
+  /// way: the channel ages its status from elapsed time alone, so a source that
+  /// ignores every failure still goes stale and then offline on schedule and
+  /// nothing here can present a dead feed as current.
+  ///
+  /// Only a replay source has cause to override it — it polls a fixed instant
+  /// in the past, where "this far back is no longer retained" is an answer, not
+  /// a fault. For a live feed every failure is a real one; leave this alone.
   bool isIgnorableFailure(Failure failure) => false;
 
   /// Drops any transport the source is holding open while the app is in the
diff --git a/lib/features/earthquake/data/rts_replay_source.dart b/lib/features/earthquake/data/rts_replay_source.dart
index 55cc1202f..caee7b2d4 100644
--- a/lib/features/earthquake/data/rts_replay_source.dart
+++ b/lib/features/earthquake/data/rts_replay_source.dart
@@ -1,3 +1,4 @@
+import 'package:dpip/core/error/failure.dart';
 import 'package:dpip/core/error/result.dart';
 import 'package:dpip/core/network/api_exception.dart';
 import 'package:dpip/core/realtime/realtime_source.dart';
@@ -5,8 +6,6 @@ import 'package:dpip/core/realtime/replay_clock.dart';
 import 'package:dpip/features/earthquake/data/earthquake_api.dart';
 import 'package:dpip/features/earthquake/domain/rts.dart';
 
-import '../../../core/error/failure.dart';
-
 /// Replays the RTS feed at a fixed point in the past — a plain **polling**
 /// source (not SSE): each [fetch] asks [EarthquakeApi.getRtsAt] for the
 /// snapshot at the current second of [clock], which ticks 1:1 with real time
@@ -27,8 +26,14 @@ class RtsReplaySource extends RealtimeSource<Rts> {
     final seconds = clock.now().millisecondsSinceEpoch ~/ 1000;
     final json = await _api.getRtsAt(seconds);
     return Rts.fromJson(json as Map<String, dynamic>);
-  }, shouldLog: (failure) => failure is! NotFoundFailure);
+  }, shouldLog: (failure) => !isIgnorableFailure(failure));
 
+  /// A 404 is the ordinary shape of an old replay, not a fault: RTS snapshots
+  /// are retained for far less time than the EEW history, so an event old
+  /// enough (0403, say) still has alerts to replay and no shaking left to draw.
+  /// Counted as a failure it would be one crash report and one log line **per
+  /// second** for the whole session — the poll runs at 1 Hz, which never trips
+  /// `Log`'s repeat suppression (8 within 5s).
   @override
   bool isIgnorableFailure(Failure failure) => failure is NotFoundFailure;
 
diff --git a/lib/features/earthquake/presentation/pages/report_replay_page.dart b/lib/features/earthquake/presentation/pages/report_replay_page.dart
index 9e347d8ac..53e8c96b4 100644
--- a/lib/features/earthquake/presentation/pages/report_replay_page.dart
+++ b/lib/features/earthquake/presentation/pages/report_replay_page.dart
@@ -1342,12 +1342,18 @@ class _ReplayStatusBar extends StatelessWidget {
     final taipeiTime = AppTime.taipei(clock.now());
     final timeText = _clockFormat.format(taipeiTime);
 
-    final (Color dot, String? statusWord) = switch (rts.status) {
-      RealtimeStatus.live => (Colors.green, null),
-      RealtimeStatus.stale => (Colors.amber, l10n.feedStale),
-      RealtimeStatus.offline => (Colors.red, l10n.feedOffline),
-      RealtimeStatus.connecting => (Colors.grey, l10n.feedConnecting),
-    };
+    // RTS snapshots age out of the server long before the EEW history does, so
+    // an old enough event replays as alerts over a map with no shaking on it.
+    // That feed is not broken and saying "連線中斷" reads as a broken app —
+    // the replay is running, there is just nothing recorded that far back.
+    final (Color dot, String? statusWord) = rts.isMissingHistory
+        ? (Colors.orange, l10n.feedReplaying)
+        : switch (rts.status) {
+            RealtimeStatus.live => (Colors.green, null),
+            RealtimeStatus.stale => (Colors.amber, l10n.feedStale),
+            RealtimeStatus.offline => (Colors.red, l10n.feedOffline),
+            RealtimeStatus.connecting => (Colors.grey, l10n.feedConnecting),
+          };
 
     final alertCount = eew.alerts.length;
     final hasActiveEew = alertCount > 0;
diff --git a/lib/features/earthquake/presentation/rts_realtime_controller.dart b/lib/features/earthquake/presentation/rts_realtime_controller.dart
index ecda87ab7..6df35c7b9 100644
--- a/lib/features/earthquake/presentation/rts_realtime_controller.dart
+++ b/lib/features/earthquake/presentation/rts_realtime_controller.dart
@@ -1,3 +1,4 @@
+import 'package:dpip/core/error/failure.dart';
 import 'package:dpip/core/realtime/realtime_notifier.dart';
 import 'package:dpip/core/realtime/realtime_state.dart';
 import 'package:dpip/features/earthquake/domain/rts.dart';
@@ -29,4 +30,12 @@ class RtsRealtimeController extends RealtimeNotifier<Rts> {
 
   /// Whether the feed has aged past the freshness threshold.
   bool get isStale => status == RealtimeStatus.stale;
+
+  /// Whether the last poll found no snapshot for the instant it asked for.
+  ///
+  /// Only a replay reaches this: RTS snapshots are retained for far less time
+  /// than the EEW history, so an old enough event still has alerts to replay
+  /// and no shaking left to draw. The feed is not broken, so a UI must not call
+  /// it disconnected — there is simply nothing recorded that far back.
+  bool get isMissingHistory => state.lastFailure is NotFoundFailure;
 }
diff --git a/lib/l10n/app_en.arb b/lib/l10n/app_en.arb
index b0bb8156a..b2018d793 100644
--- a/lib/l10n/app_en.arb
+++ b/lib/l10n/app_en.arb
@@ -831,6 +831,7 @@
   },
   "moreSectionLinks": "Links",
   "feedOffline": "Connection lost",
+  "feedReplaying": "Replaying",
   "mapLayerStyleBd": "Dvorak BD",
   "@mapLayerSatelliteB09": {
     "description": "Himawari mid-level water-vapour channel (B09, 6.9 µm) layer name"
@@ -1136,6 +1137,9 @@
   "@feedOffline": {
     "description": "Banner/headline when a realtime feed has gone offline"
   },
+  "@feedReplaying": {
+    "description": "Status word on the replay page when the replayed instant is older than the RTS retention window: the replay is running, the server just has no shaking snapshot that far back. Never 'offline' — the feed is not broken"
+  },
   "reportFilterIntensityInfoModernTitle": "Current (from 2020)",
   "@mapAppGoogleMaps": {
     "description": "External map app choice: Google Maps"
diff --git a/lib/l10n/app_fil.arb b/lib/l10n/app_fil.arb
index 02e6014d1..b38b0f46b 100644
--- a/lib/l10n/app_fil.arb
+++ b/lib/l10n/app_fil.arb
@@ -284,6 +284,7 @@
   "reportListYesterday": "Kahapon",
   "moreSectionLinks": "Mga Link",
   "feedOffline": "Nawala ang koneksyon",
+  "feedReplaying": "Nire-replay",
   "mapLayerStyleBd": "Dvorak BD",
   "moreSectionDisplay": "Display",
   "rainInterval3d": "3 araw",
diff --git a/lib/l10n/app_id.arb b/lib/l10n/app_id.arb
index 0b4c57c32..2860d3038 100644
--- a/lib/l10n/app_id.arb
+++ b/lib/l10n/app_id.arb
@@ -284,6 +284,7 @@
   "reportListYesterday": "Kemarin",
   "moreSectionLinks": "Tautan",
   "feedOffline": "Koneksi terputus",
+  "feedReplaying": "Memutar ulang",
   "mapLayerStyleBd": "Dvorak BD",
   "moreSectionDisplay": "Tampilan",
   "rainInterval3d": "3 hr",
diff --git a/lib/l10n/app_ja.arb b/lib/l10n/app_ja.arb
index cfe219f27..0ebbe5d6f 100644
--- a/lib/l10n/app_ja.arb
+++ b/lib/l10n/app_ja.arb
@@ -284,6 +284,7 @@
   "reportListYesterday": "昨日",
   "moreSectionLinks": "関連リンク",
   "feedOffline": "接続が切断されました",
+  "feedReplaying": "再生中",
   "mapLayerStyleBd": "Dvorak BD",
   "moreSectionDisplay": "表示",
   "rainInterval3d": "3日",
diff --git a/lib/l10n/app_ko.arb b/lib/l10n/app_ko.arb
index a5f5e97e3..787c107f9 100644
--- a/lib/l10n/app_ko.arb
+++ b/lib/l10n/app_ko.arb
@@ -284,6 +284,7 @@
   "reportListYesterday": "어제",
   "moreSectionLinks": "링크",
   "feedOffline": "연결이 끊어졌습니다",
+  "feedReplaying": "재생 중",
   "mapLayerStyleBd": "Dvorak BD",
   "moreSectionDisplay": "표시",
   "rainInterval3d": "3일",
diff --git a/lib/l10n/app_th.arb b/lib/l10n/app_th.arb
index b6c184c6d..705871ac6 100644
--- a/lib/l10n/app_th.arb
+++ b/lib/l10n/app_th.arb
@@ -284,6 +284,7 @@
   "reportListYesterday": "เมื่อวาน",
   "moreSectionLinks": "ลิงก์ที่เกี่ยวข้อง",
   "feedOffline": "การเชื่อมต่อขาดหาย",
+  "feedReplaying": "กำลังเล่นซ้ำ",
   "mapLayerStyleBd": "Dvorak BD",
   "moreSectionDisplay": "การแสดงผล",
   "rainInterval3d": "3 วัน",
diff --git a/lib/l10n/app_vi.arb b/lib/l10n/app_vi.arb
index 0e25756c1..13d337b5f 100644
--- a/lib/l10n/app_vi.arb
+++ b/lib/l10n/app_vi.arb
@@ -284,6 +284,7 @@
   "reportListYesterday": "Hôm qua",
   "moreSectionLinks": "Liên kết",
   "feedOffline": "Mất kết nối",
+  "feedReplaying": "Đang phát lại",
   "mapLayerStyleBd": "Dvorak BD",
   "moreSectionDisplay": "Hiển thị",
   "rainInterval3d": "3 ngày",
diff --git a/lib/l10n/app_yue.arb b/lib/l10n/app_yue.arb
index 8df7c7431..4b05be91c 100644
--- a/lib/l10n/app_yue.arb
+++ b/lib/l10n/app_yue.arb
@@ -286,6 +286,7 @@
   "reportListYesterday": "昨天",
   "moreSectionLinks": "相關連結",
   "feedOffline": "連接中斷",
+  "feedReplaying": "重播緊",
   "mapLayerStyleBd": "Dvorak BD",
   "moreSectionDisplay": "顯示",
   "rainInterval3d": "3 日",
diff --git a/lib/l10n/app_zh.arb b/lib/l10n/app_zh.arb
index 06cd6a355..3d94cd0fd 100644
--- a/lib/l10n/app_zh.arb
+++ b/lib/l10n/app_zh.arb
@@ -284,6 +284,7 @@
   "reportListYesterday": "昨天",
   "moreSectionLinks": "相關連結",
   "feedOffline": "連線中斷",
+  "feedReplaying": "重播中",
   "mapLayerStyleBd": "Dvorak BD",
   "moreSectionDisplay": "顯示",
   "rainInterval3d": "3 日",
diff --git a/lib/l10n/app_zh_Hans.arb b/lib/l10n/app_zh_Hans.arb
index 318a6dff7..cb72be38e 100644
--- a/lib/l10n/app_zh_Hans.arb
+++ b/lib/l10n/app_zh_Hans.arb
@@ -284,6 +284,7 @@
   "reportListYesterday": "昨天",
   "moreSectionLinks": "相关链接",
   "feedOffline": "连接中断",
+  "feedReplaying": "重播中",
   "mapLayerStyleBd": "Dvorak BD",
   "moreSectionDisplay": "显示",
   "rainInterval3d": "3 日",
diff --git a/lib/l10n/app_zh_Hant_HK.arb b/lib/l10n/app_zh_Hant_HK.arb
index d55860c70..cb9c46e94 100644
--- a/lib/l10n/app_zh_Hant_HK.arb
+++ b/lib/l10n/app_zh_Hant_HK.arb
@@ -284,6 +284,7 @@
   "reportListYesterday": "昨天",
   "moreSectionLinks": "相關連結",
   "feedOffline": "連接中斷",
+  "feedReplaying": "重播中",
   "mapLayerStyleBd": "Dvorak BD",
   "moreSectionDisplay": "顯示",
   "rainInterval3d": "3 日",
diff --git a/lib/l10n/app_zh_TW.arb b/lib/l10n/app_zh_TW.arb
index 712899bbf..b24e0505f 100644
--- a/lib/l10n/app_zh_TW.arb
+++ b/lib/l10n/app_zh_TW.arb
@@ -284,6 +284,7 @@
   "reportListYesterday": "昨天",
   "moreSectionLinks": "相關連結",
   "feedOffline": "連線中斷",
+  "feedReplaying": "重播中",
   "mapLayerStyleBd": "Dvorak BD",
   "moreSectionDisplay": "顯示",
   "rainInterval3d": "3 日",
diff --git a/lib/l10n/gen/app_localizations.dart b/lib/l10n/gen/app_localizations.dart
index 3061da64b..e9912f770 100644
--- a/lib/l10n/gen/app_localizations.dart
+++ b/lib/l10n/gen/app_localizations.dart
@@ -1265,6 +1265,12 @@ abstract class AppLocalizations {
   /// **'Connection lost'**
   String get feedOffline;
 
+  /// Status word on the replay page when the replayed instant is older than the RTS retention window: the replay is running, the server just has no shaking snapshot that far back. Never 'offline' — the feed is not broken
+  ///
+  /// In en, this message translates to:
+  /// **'Replaying'**
+  String get feedReplaying;
+
   /// Colour-style option: Dvorak BD curve stepped grayscale
   ///
   /// In en, this message translates to:
diff --git a/lib/l10n/gen/app_localizations_en.dart b/lib/l10n/gen/app_localizations_en.dart
index 3b682ae57..aeafddcc2 100644
--- a/lib/l10n/gen/app_localizations_en.dart
+++ b/lib/l10n/gen/app_localizations_en.dart
@@ -631,6 +631,9 @@ class AppLocalizationsEn extends AppLocalizations {
   @override
   String get feedOffline => 'Connection lost';
 
+  @override
+  String get feedReplaying => 'Replaying';
+
   @override
   String get mapLayerStyleBd => 'Dvorak BD';
 
diff --git a/lib/l10n/gen/app_localizations_fil.dart b/lib/l10n/gen/app_localizations_fil.dart
index 65604e5bc..5baed22f8 100644
--- a/lib/l10n/gen/app_localizations_fil.dart
+++ b/lib/l10n/gen/app_localizations_fil.dart
@@ -634,6 +634,9 @@ class AppLocalizationsFil extends AppLocalizations {
   @override
   String get feedOffline => 'Nawala ang koneksyon';
 
+  @override
+  String get feedReplaying => 'Nire-replay';
+
   @override
   String get mapLayerStyleBd => 'Dvorak BD';
 
diff --git a/lib/l10n/gen/app_localizations_id.dart b/lib/l10n/gen/app_localizations_id.dart
index bfe1d624f..273b7834a 100644
--- a/lib/l10n/gen/app_localizations_id.dart
+++ b/lib/l10n/gen/app_localizations_id.dart
@@ -632,6 +632,9 @@ class AppLocalizationsId extends AppLocalizations {
   @override
   String get feedOffline => 'Koneksi terputus';
 
+  @override
+  String get feedReplaying => 'Memutar ulang';
+
   @override
   String get mapLayerStyleBd => 'Dvorak BD';
 
diff --git a/lib/l10n/gen/app_localizations_ja.dart b/lib/l10n/gen/app_localizations_ja.dart
index b2b84b383..1fbb99eae 100644
--- a/lib/l10n/gen/app_localizations_ja.dart
+++ b/lib/l10n/gen/app_localizations_ja.dart
@@ -623,6 +623,9 @@ class AppLocalizationsJa extends AppLocalizations {
   @override
   String get feedOffline => '接続が切断されました';
 
+  @override
+  String get feedReplaying => '再生中';
+
   @override
   String get mapLayerStyleBd => 'Dvorak BD';
 
diff --git a/lib/l10n/gen/app_localizations_ko.dart b/lib/l10n/gen/app_localizations_ko.dart
index c9f516da2..8377fe20b 100644
--- a/lib/l10n/gen/app_localizations_ko.dart
+++ b/lib/l10n/gen/app_localizations_ko.dart
@@ -622,6 +622,9 @@ class AppLocalizationsKo extends AppLocalizations {
   @override
   String get feedOffline => '연결이 끊어졌습니다';
 
+  @override
+  String get feedReplaying => '재생 중';
+
   @override
   String get mapLayerStyleBd => 'Dvorak BD';
 
diff --git a/lib/l10n/gen/app_localizations_th.dart b/lib/l10n/gen/app_localizations_th.dart
index 4346de7fa..288d3b439 100644
--- a/lib/l10n/gen/app_localizations_th.dart
+++ b/lib/l10n/gen/app_localizations_th.dart
@@ -629,6 +629,9 @@ class AppLocalizationsTh extends AppLocalizations {
   @override
   String get feedOffline => 'การเชื่อมต่อขาดหาย';
 
+  @override
+  String get feedReplaying => 'กำลังเล่นซ้ำ';
+
   @override
   String get mapLayerStyleBd => 'Dvorak BD';
 
diff --git a/lib/l10n/gen/app_localizations_vi.dart b/lib/l10n/gen/app_localizations_vi.dart
index 9817eef11..9ab556fe5 100644
--- a/lib/l10n/gen/app_localizations_vi.dart
+++ b/lib/l10n/gen/app_localizations_vi.dart
@@ -629,6 +629,9 @@ class AppLocalizationsVi extends AppLocalizations {
   @override
   String get feedOffline => 'Mất kết nối';
 
+  @override
+  String get feedReplaying => 'Đang phát lại';
+
   @override
   String get mapLayerStyleBd => 'Dvorak BD';
 
diff --git a/lib/l10n/gen/app_localizations_yue.dart b/lib/l10n/gen/app_localizations_yue.dart
index 5a5af9485..27e8bbbac 100644
--- a/lib/l10n/gen/app_localizations_yue.dart
+++ b/lib/l10n/gen/app_localizations_yue.dart
@@ -619,6 +619,9 @@ class AppLocalizationsYue extends AppLocalizations {
   @override
   String get feedOffline => '連接中斷';
 
+  @override
+  String get feedReplaying => '重播緊';
+
   @override
   String get mapLayerStyleBd => 'Dvorak BD';
 
diff --git a/lib/l10n/gen/app_localizations_zh.dart b/lib/l10n/gen/app_localizations_zh.dart
index e158b2952..3b965b2e1 100644
--- a/lib/l10n/gen/app_localizations_zh.dart
+++ b/lib/l10n/gen/app_localizations_zh.dart
@@ -619,6 +619,9 @@ class AppLocalizationsZh extends AppLocalizations {
   @override
   String get feedOffline => '連線中斷';
 
+  @override
+  String get feedReplaying => '重播中';
+
   @override
   String get mapLayerStyleBd => 'Dvorak BD';
 
@@ -3854,6 +3857,9 @@ class AppLocalizationsZhHans extends AppLocalizationsZh {
   @override
   String get feedOffline => '连接中断';
 
+  @override
+  String get feedReplaying => '重播中';
+
   @override
   String get mapLayerStyleBd => 'Dvorak BD';
 
@@ -7089,6 +7095,9 @@ class AppLocalizationsZhHantHk extends AppLocalizationsZh {
   @override
   String get feedOffline => '連接中斷';
 
+  @override
+  String get feedReplaying => '重播中';
+
   @override
   String get mapLayerStyleBd => 'Dvorak BD';
 
@@ -10324,6 +10333,9 @@ class AppLocalizationsZhTw extends AppLocalizationsZh {
   @override
   String get feedOffline => '連線中斷';
 
+  @override
+  String get feedReplaying => '重播中';
+
   @override
   String get mapLayerStyleBd => 'Dvorak BD';
 
diff --git a/test/core/network/api_exception_test.dart b/test/core/network/api_exception_test.dart
index 5cfc13ad2..799b3bd98 100644
--- a/test/core/network/api_exception_test.dart
+++ b/test/core/network/api_exception_test.dart
@@ -1,9 +1,22 @@
 import 'package:dio/dio.dart';
 import 'package:dpip/core/error/failure.dart';
 import 'package:dpip/core/error/result.dart';
+import 'package:dpip/core/logging/log.dart';
 import 'package:dpip/core/network/api_exception.dart';
 import 'package:flutter_test/flutter_test.dart';
 
+Future<Result<int>> _throwing({bool Function(Failure)? shouldLog}) =>
+    guardResult<int>(() async {
+      throw DioException(
+        requestOptions: RequestOptions(),
+        type: DioExceptionType.badResponse,
+        response: Response<void>(
+          requestOptions: RequestOptions(),
+          statusCode: 404,
+        ),
+      );
+    }, shouldLog: shouldLog);
+
 void main() {
   group('guardResult', () {
     test('returns Ok with the body value on success', () async {
@@ -30,5 +43,30 @@ void main() {
       });
       expect(result.failureOrNull, isA<DecodeFailure>());
     });
+
+    test('logs the failure by default', () async {
+      Log.talker.cleanHistory();
+      final result = await _throwing();
+      expect(result.failureOrNull, isA<NotFoundFailure>());
+      expect(Log.talker.history, isNotEmpty);
+    });
+
+    test('shouldLog:false drops the log line but still returns Err', () async {
+      Log.talker.cleanHistory();
+      Failure? seen;
+      final result = await _throwing(
+        shouldLog: (failure) {
+          seen = failure;
+          return false;
+        },
+      );
+      // The suppression is of the log line only — a caller can never mistake a
+      // quiet failure for a success.
+      expect(result, isA<Err<int>>());
+      expect(result.failureOrNull, isA<NotFoundFailure>());
+      // And it decides on the classified failure, not the raw exception.
+      expect(seen, isA<NotFoundFailure>());
+      expect(Log.talker.history, isEmpty);
+    });
   });
 }
diff --git a/test/core/realtime/realtime_channel_test.dart b/test/core/realtime/realtime_channel_test.dart
index 8bcb24969..a1cfa1bed 100644
--- a/test/core/realtime/realtime_channel_test.dart
+++ b/test/core/realtime/realtime_channel_test.dart
@@ -53,6 +53,11 @@ class _FakeSource extends RealtimeSource<int> {
   Result<int> next = const Ok(0);
   Completer<Result<int>>? pending;
 
+  /// Only a replay source overrides this in production; here it lets a test
+  /// pick which failures the channel should treat as "no data for that
+  /// instant" rather than as a fault.
+  bool Function(Failure)? ignorable;
+
   @override
   Future<Result<int>> fetch() async {
     fetchCount++;
@@ -62,6 +67,9 @@ class _FakeSource extends RealtimeSource<int> {
 
   @override
   DateTime? timestampOf(int value) => null; // fetch-freshness
+
+  @override
+  bool isIgnorableFailure(Failure failure) => ignorable?.call(failure) ?? false;
 }
 
 /// Flushes pending microtasks so broadcast emissions and unawaited fetches land.
@@ -180,6 +188,53 @@ void main() {
     expect(channel.state.lastFailure, isNull);
   });
 
+  test('an ignorable failure is recorded but not counted', () async {
+    source.ignorable = (failure) => failure is NotFoundFailure;
+    source.next = const Ok(9);
+    await channel.refreshNow();
+    await pump();
+    final count = events.length;
+
+    source.next = const Err(NotFoundFailure('nothing at that instant'));
+    await channel.refreshNow();
+    await pump();
+    expect(channel.state.data, 9); // the last snapshot is kept
+    // The reason is kept for the UI (a replay says so instead of calling
+    // itself disconnected) without being charged to the feed as a fault.
+    expect(channel.state.lastFailure, isA<NotFoundFailure>());
+    expect(channel.state.consecutiveFailures, 0);
+    expect(events.length, count + 1);
+
+    // A repeat of the same kind is not republished: at 1 Hz that would be a
+    // rebuild a second for the length of the replay.
+    await channel.refreshNow();
+    await pump();
+    expect(events.length, count + 1);
+
+    // Recovering clears the reason, and says so even though the status word
+    // never moved.
+    source.next = const Ok(10);
+    await channel.refreshNow();
+    await pump();
+    expect(channel.state.lastFailure, isNull);
+    expect(events.length, count + 2);
+  });
+
+  test('an ignored failure still ages the feed to offline', () async {
+    // The safety property: ignoring a failure silences the *record* of it, and
+    // must never keep a feed that is receiving nothing looking current.
+    source.ignorable = (failure) => failure is NotFoundFailure;
+    source.next = const Err(NotFoundFailure('retention ran out'));
+    channel.start();
+    await pump();
+    expect(channel.state.status, RealtimeStatus.connecting);
+
+    elapsed.advance(const Duration(seconds: 11)); // > offlineAfter(10)
+    ticker.fire();
+    await pump();
+    expect(channel.state.status, RealtimeStatus.offline);
+  });
+
   test('a slow poll is not stacked by the next tick', () async {
     source.next = const Ok(1);
     channel.start();

From 1619934ac42465d941cb7851700ca34c736705f3 Mon Sep 17 00:00:00 2001
From: PiscesXD <rclu2881@gmail.com>
Date: Thu, 10 Sep 2026 11:03:44 +0800
Subject: [PATCH 3/3] fix(network): stop blaming the region for a missing
 resource
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Fix(zh-Hant): 伺服器狀態不再因為某筆資料找不到，就把整個連線區域標成離線
Fix(en-US): a missing resource no longer marks a whole API region as down
---
 lib/core/network/api_client.dart       | 17 +++++++++++++----
 test/core/network/api_client_test.dart | 22 ++++++++++++++++++++++
 2 files changed, 35 insertions(+), 4 deletions(-)

diff --git a/lib/core/network/api_client.dart b/lib/core/network/api_client.dart
index b92c4ee79..b707869e4 100644
--- a/lib/core/network/api_client.dart
+++ b/lib/core/network/api_client.dart
@@ -188,9 +188,15 @@ class ApiClient {
         _health?.success(tier, hosts[i], path);
         return response;
       } on DioException catch (e) {
-        _health?.failure(tier, hosts[i], path);
+        final retryable = _isRetryable(e);
+        // Only what the *host* is answerable for, which is what [_isRetryable]
+        // already separates. A 404 says the route or the resource is wrong, not
+        // that the region is sick: replaying an event older than the RTS
+        // retention 404s once a second, and charging those to the host parked
+        // `api-1` at `down` on the status screen for the rest of the session.
+        if (retryable) _health?.failure(tier, hosts[i], path);
         final isLastHost = i == hosts.length - 1;
-        if (isLastHost || !_isRetryable(e)) rethrow;
+        if (isLastHost || !retryable) rethrow;
         Log.warning(
           'ApiClient: ${tier.name} ${hosts[i]} failed (${_describe(e)}); '
           'failing over to ${hosts[i + 1]}',
@@ -239,9 +245,12 @@ class ApiClient {
         _health?.success(tier, hosts[i], path);
         return StreamedResponse(response.data!.stream, cancelToken.cancel);
       } on DioException catch (e) {
-        _health?.failure(tier, hosts[i], path);
+        // Same split as [request]: a host is only charged for what it is
+        // answerable for.
+        final retryable = _isRetryable(e);
+        if (retryable) _health?.failure(tier, hosts[i], path);
         final isLastHost = i == hosts.length - 1;
-        if (isLastHost || !_isRetryable(e)) rethrow;
+        if (isLastHost || !retryable) rethrow;
         Log.warning(
           'ApiClient: ${tier.name} stream ${hosts[i]} failed (${_describe(e)}); '
           'failing over to ${hosts[i + 1]}',
diff --git a/test/core/network/api_client_test.dart b/test/core/network/api_client_test.dart
index b4e940346..e579f1640 100644
--- a/test/core/network/api_client_test.dart
+++ b/test/core/network/api_client_test.dart
@@ -175,6 +175,28 @@ void main() {
     expect(health.summary, EndpointState.degraded);
   });
 
+  test('a 4xx is not charged to the host', () async {
+    // A 404 says the route or the resource is wrong, not that the region is
+    // sick. Replaying an event older than the RTS retention 404s once a second,
+    // and counting those parked the host at `down` for the rest of the session.
+    final health = EndpointHealthMonitor();
+    final adapter = _FakeAdapter((_, _) => _json('{"err":"bad"}', 404));
+    await expectLater(
+      () => monitoredClient(adapter, health).request(ApiTier.lbApi, '/x'),
+      throwsA(isA<DioException>()),
+    );
+
+    expect(
+      health.of(
+        EndpointService.other,
+        ApiTier.lbApi,
+        'api.lb-tpe1.exptech.dev',
+      ),
+      isNull, // untouched, not merely still healthy
+    );
+    expect(health.summary, EndpointState.unknown);
+  });
+
   test('exclusive and core tiers track the same host separately', () async {
     final health = EndpointHealthMonitor();
     final adapter = _FakeAdapter((_, _) => _json('{"ok":true}', 200));