PE-9211: The version list becomes a control the recipient can use

lib/blocs/shared_file/shared_file_cubit.dart

@@ -326,7 +326,16 @@ class SharedFileCubit extends Cubit<SharedFileState> {
     final resolution = _resolution;
     final fileKey = _lastAttemptedFileKey;
 
-    emit(current.copyWith(activityStatus: SharedFileActivityStatus.loading));
+    emit(current.copyWith(
+      activityStatus: SharedFileActivityStatus.loading,
+      // The version the link named is already in hand - it is what the page is
+      // showing. It renders the moment the list is opened, and the rest of the
+      // history fills in around it, so expanding never costs a wait and a
+      // failed lookup never empties the list.
+      activityRevisions: current.activityRevisions.isEmpty
+          ? [current.sharedRevision]
+          : current.activityRevisions,
+    ));
 
     try {
       final entities = await _bounded(
@@ -371,6 +380,45 @@ class SharedFileCubit extends Cubit<SharedFileState> {
     }
   }
 
+  /// Makes [revision] what the page shows and downloads.
+  ///
+  /// The version list's own action. [showLatestRevision] and
+  /// [showSharedRevision] remain the banner's two shortcuts; this is the
+  /// general case behind them, so a recipient can pick any version the file
+  /// has rather than only the two the page happens to offer.
+  ///
+  /// The banner stays honest afterwards because "a newer version exists" is
+  /// re-derived from where the selection landed: on the newest revision there
+  /// is nothing newer to offer, and on any older one there is.
+  ///
+  /// Selecting is deliberate, so unlike the freshness check it *does* move the
+  /// download target - that is the whole point of the control. Nothing moves it
+  /// on the recipient's behalf.
+  Future<void> showRevision(FileRevision revision) async {
+    final current = state;
+
+    if (current is! SharedFileLoadSuccess) {
+      return;
+    }
+
+    // Already the target. Re-emitting would drop the license for no reason.
+    if (revision.dataTxId == current.revision.dataTxId) {
+      return;
+    }
+
+    final history = current.activityRevisions;
+    final isNewest =
+        history.isNotEmpty && revision.dataTxId == history.first.dataTxId;
+
+    emit(_withTarget(current, revision, showsLatestRevision: isNewest));
+
+    await _fetchLicense(
+      revision,
+      current.ownerAddress,
+      resolution: _resolution,
+    );
+  }
+
   /// Takes the file's newest revision as what the page shows and downloads.
   ///
   /// The freshness check never moves the target; it raises a flag, and the page
@@ -1683,8 +1731,8 @@ class SharedFileCubit extends Cubit<SharedFileState> {
         parentFolderId: '',
         name: payload.name ?? '',
         size: payload.size ?? 0,
-        lastModifiedDate: _unknownDate,
-        dateCreated: _unknownDate,
+        lastModifiedDate: unknownDate,
+        dateCreated: unknownDate,
         metadataTxId: payload.metadataTxId ?? '',
         dataTxId: payload.dataTxId!,
         dataContentType: payload.contentType,
@@ -1805,7 +1853,14 @@ class SharedFileCubit extends Cubit<SharedFileState> {
   bool _isStale(int resolution) => isClosed || resolution != _resolution;
 
   /// The link carries no timestamps. Rendered as "unknown", never as 1970.
-  static final _unknownDate = DateTime.fromMillisecondsSinceEpoch(0);
+  static final unknownDate = DateTime.fromMillisecondsSinceEpoch(0);
+
+  /// Whether [date] is the placeholder a link-derived revision carries.
+  ///
+  /// A link carries no timestamps, so anything painted from one has this in
+  /// place of a date. The UI asks rather than rendering it: shown, it reads as
+  /// 1 January 1970, which is worse than showing nothing.
+  static bool isUnknownDate(DateTime date) => date == unknownDate;
 }
 
 /// A revision resolved straight from its metadata transaction.

lib/l10n/app_en.arb

@@ -2146,6 +2146,10 @@
   "@sharedFileAccessKeyStaysOnThisDevice": {
     "description": "Reassurance shown under the access key field on the shared file page"
   },
+  "sharedFileTransactionDetails": "Transaction details",
+  "@sharedFileTransactionDetails": {
+    "description": "Nested disclosure inside the file details tab, holding the identifiers a recipient never needs to see"
+  },
   "sharedFileDetailsDrawerTitle": "File details",
   "@sharedFileDetailsDrawerTitle": {
     "description": "Title of the collapsed drawer holding the technical details of a shared file"
@@ -2242,10 +2246,6 @@
   "@sharedFilePasteAccessKey": {
     "description": "Placeholder of the access key field on the shared file page"
   },
-  "sharedFilePermanentFileSharing": "Permanent file sharing",
-  "@sharedFilePermanentFileSharing": {
-    "description": "Tagline shown under the ArDrive logo on the shared file page"
-  },
   "sharedFilePreviewPaneHint": "Preview this file here without downloading it.",
   "@sharedFilePreviewPaneHint": {
     "description": "Caption in the preview pane of the shared file page, on a desktop screen, saying what pressing Preview will do"
@@ -2298,10 +2298,6 @@
       }
     }
   },
-  "sharedFileStoredPermanently": "This file is stored permanently and can be downloaded any time.",
-  "@sharedFileStoredPermanently": {
-    "description": "Reassurance shown at the bottom of the shared file page"
-  },
   "sharedFileUnlockedWithAccessKey": "Unlocked with your access key. This file stays encrypted for everyone else.",
   "@sharedFileUnlockedWithAccessKey": {
     "description": "Shown after a private shared file has been unlocked with an access key"
@@ -2362,6 +2358,26 @@
   "@shareDriveSendKeySeparately": {
     "description": "Helper text under the drive key field explaining the two-artifact handover"
   },
+  "sharedFileChooseVersion": "Choose which version to download.",
+  "@sharedFileChooseVersion": {
+    "description": "Helper line above the recipient's list of file versions"
+  },
+  "sharedFileVersionLatest": "Latest",
+  "@sharedFileVersionLatest": {
+    "description": "Chip marking the newest version in the recipient's version list"
+  },
+  "sharedFileVersionPinned": "Pinned",
+  "@sharedFileVersionPinned": {
+    "description": "Chip marking the version a pinned share link deliberately points at, as opposed to merely the version the link carried"
+  },
+  "sharedFileVersionsLooking": "Looking for other versions\u2026",
+  "@sharedFileVersionsLooking": {
+    "description": "Shown while the rest of a file's version history is being fetched"
+  },
+  "sharedFileVersionsUnavailableShort": "Couldn\u2019t check for other versions.",
+  "@sharedFileVersionsUnavailableShort": {
+    "description": "Shown when the version history could not be read; the version the recipient was sent is still listed and downloadable"
+  },
   "attachDriveLookingUp": "Looking up drive…",
   "@attachDriveLookingUp": {
     "description": "Shown while the entered drive ID is being resolved"

lib/l10n/app_es.arb

@@ -1877,10 +1877,6 @@
   "@sharedFilePasteAccessKey": {
     "description": "Placeholder of the access key field on the shared file page"
   },
-  "sharedFilePermanentFileSharing": "Compartir archivos de forma permanente",
-  "@sharedFilePermanentFileSharing": {
-    "description": "Tagline shown under the ArDrive logo on the shared file page"
-  },
   "sharedFilePreviewPaneHint": "Previsualiza este archivo aquí, sin descargarlo.",
   "@sharedFilePreviewPaneHint": {
     "description": "Caption in the preview pane of the shared file page, on a desktop screen, saying what pressing Preview will do"

lib/l10n/app_hi.arb

@@ -1877,10 +1877,6 @@
   "@sharedFilePasteAccessKey": {
     "description": "Placeholder of the access key field on the shared file page"
   },
-  "sharedFilePermanentFileSharing": "स्थायी फ़ाइल शेयरिंग",
-  "@sharedFilePermanentFileSharing": {
-    "description": "Tagline shown under the ArDrive logo on the shared file page"
-  },
   "sharedFilePreviewPaneHint": "इस फ़ाइल को डाउनलोड किए बिना यहीं देखें।",
   "@sharedFilePreviewPaneHint": {
     "description": "Caption in the preview pane of the shared file page, on a desktop screen, saying what pressing Preview will do"

lib/l10n/app_ja.arb

@@ -1877,10 +1877,6 @@
   "@sharedFilePasteAccessKey": {
     "description": "Placeholder of the access key field on the shared file page"
   },
-  "sharedFilePermanentFileSharing": "永続的なファイル共有",
-  "@sharedFilePermanentFileSharing": {
-    "description": "Tagline shown under the ArDrive logo on the shared file page"
-  },
   "sharedFilePreviewPaneHint": "ダウンロードせずに、このファイルをここでプレビューできます。",
   "@sharedFilePreviewPaneHint": {
     "description": "Caption in the preview pane of the shared file page, on a desktop screen, saying what pressing Preview will do"

lib/l10n/app_zh-HK.arb

@@ -1877,10 +1877,6 @@
   "@sharedFilePasteAccessKey": {
     "description": "Placeholder of the access key field on the shared file page"
   },
-  "sharedFilePermanentFileSharing": "永久檔案分享",
-  "@sharedFilePermanentFileSharing": {
-    "description": "Tagline shown under the ArDrive logo on the shared file page"
-  },
   "sharedFilePreviewPaneHint": "無需下載，即可在這裡預覽此檔案。",
   "@sharedFilePreviewPaneHint": {
     "description": "Caption in the preview pane of the shared file page, on a desktop screen, saying what pressing Preview will do"

lib/l10n/app_zh.arb

@@ -1877,10 +1877,6 @@
   "@sharedFilePasteAccessKey": {
     "description": "Placeholder of the access key field on the shared file page"
   },
-  "sharedFilePermanentFileSharing": "永久文件共享",
-  "@sharedFilePermanentFileSharing": {
-    "description": "Tagline shown under the ArDrive logo on the shared file page"
-  },
   "sharedFilePreviewPaneHint": "无需下载，即可在这里预览此文件。",
   "@sharedFilePreviewPaneHint": {
     "description": "Caption in the preview pane of the shared file page, on a desktop screen, saying what pressing Preview will do"

lib/pages/raw_transaction_view/raw_transaction_view_page.dart

@@ -190,7 +190,6 @@ class _RawTransactionReadyViewState extends State<_RawTransactionReadyView> {
 
   @override
   Widget build(BuildContext context) {
-    final colors = ArDriveTheme.of(context).themeData.colors;
     final state = widget.state;
 
     return Column(
@@ -215,14 +214,6 @@ class _RawTransactionReadyViewState extends State<_RawTransactionReadyView> {
         RawTransactionPreview(state: state),
         const SizedBox(height: 16),
         _RawTransactionDetailsDrawer(state: state),
-        const SizedBox(height: 12),
-        Text(
-          appLocalizationsOf(context).sharedFileStoredPermanently,
-          textAlign: TextAlign.center,
-          style: ArDriveTypography.body.captionRegular(
-            color: colors.themeFgSubtle,
-          ),
-        ),
       ],
     );
   }
@@ -275,7 +266,7 @@ class _RawTransactionReadyViewState extends State<_RawTransactionReadyView> {
 
 /// Where the protocol lives, one deliberate tap away.
 ///
-/// Mirrors `SharedFileDetailsDrawer`, whose row and drawer helpers are private
+/// Mirrors `SharedFileDetailsContent`, whose row and drawer helpers are private
 /// to `shared_file_ready_view.dart` and are built around a `FileRevision` that a
 /// raw transaction does not have. Extracting them would mean reshaping the
 /// recipient page's ready view around a second caller for two rows; this copy

lib/pages/shared_file/shared_file_frame.dart

@@ -130,14 +130,6 @@ class SharedFileFrame extends StatelessWidget {
             fit: BoxFit.contain,
           ),
         ),
-        const SizedBox(height: 8),
-        Text(
-          appLocalizationsOf(context).sharedFilePermanentFileSharing,
-          textAlign: TextAlign.center,
-          style: ArDriveTypography.body.captionRegular(
-            color: SharedFileColors.subtle(context),
-          ),
-        ),
       ],
     );
   }