improve tab reorder logic

Author: FaFre

app/build.yaml

@@ -15,6 +15,7 @@ targets:
                 lexo_rank_next: "text (int, text null)"
                 lexo_rank_previous: "text (int, text null)"
                 lexo_rank_reorder_after: "text (text null, text null)"
+                lexo_rank_reorder_before: "text (text null, text null)"
               modules:
                 - json1
                 - fts5

app/lib/data/database/functions/lexo_rank_functions.dart

@@ -40,6 +40,19 @@ String _reorderAfter(List<Object?> args) {
   }
 }
 
+String _reorderBefore(List<Object?> args) {
+  final first = args[0].mapNotNull((arg) => LexoRank.parse(arg as String));
+  final last = args[1].mapNotNull((arg) => LexoRank.parse(arg as String));
+
+  if (first == null) {
+    throw Exception('Tab not found');
+  } else if (last == null) {
+    return first.genPrev().value;
+  } else {
+    return last.genBetween(first).value;
+  }
+}
+
 void registerLexorankFunctions(CommonDatabase database) {
   database.createFunction(
     functionName: 'lexo_rank_next',
@@ -56,4 +69,9 @@ void registerLexorankFunctions(CommonDatabase database) {
     argumentCount: const AllowedArgumentCount(2),
     function: _reorderAfter,
   );
+  database.createFunction(
+    functionName: 'lexo_rank_reorder_before',
+    argumentCount: const AllowedArgumentCount(2),
+    function: _reorderBefore,
+  );
 }

app/lib/features/geckoview/features/browser/presentation/widgets/sheets/view_tabs.dart

@@ -300,6 +300,8 @@ class ViewTabsSheetWidget extends HookConsumerWidget {
             Expanded(
               child: HookConsumer(
                 builder: (context, ref, child) {
+                  final gridViewKey = useMemoized(() => GlobalKey());
+
                   final container = ref.watch(selectedContainerProvider);
 
                   final filteredTabEntities = ref.watch(
@@ -387,10 +389,11 @@ class ViewTabsSheetWidget extends HookConsumerWidget {
 
                   return Padding(
                     padding: const EdgeInsets.symmetric(horizontal: 4.0),
-                    child: ReorderableBuilder(
+                    child: ReorderableBuilder.builder(
                       //Rebuild when cross axis count changes
                       key: ValueKey(crossAxisCount),
                       scrollController: sheetScrollController,
+                      itemCount: tabs.length,
                       onDragStarted: (index) {
                         ref.read(willAcceptDropProvider.notifier).clear();
                       },
@@ -423,19 +426,27 @@ class ViewTabsSheetWidget extends HookConsumerWidget {
                             containerId,
                           );
                         } else {
-                          final orderAfterIndex = newIndex;
-                          key = await containerRepository.getOrderKeyAfterTab(
-                            filteredTabEntities.value[orderAfterIndex].tabId,
-                            containerId,
-                          );
+                          if (newIndex < oldIndex) {
+                            key = await containerRepository.getOrderKeyAfterTab(
+                              filteredTabEntities.value[newIndex - 1].tabId,
+                              containerId,
+                            );
+                          } else {
+                            key = await containerRepository
+                                .getOrderKeyBeforeTab(
+                                  filteredTabEntities.value[newIndex + 1].tabId,
+                                  containerId,
+                                );
+                          }
                         }
 
                         await ref
                             .read(tabDataRepositoryProvider.notifier)
                             .assignOrderKey(tabId, key);
                       },
-                      builder: (children) {
+                      childBuilder: (itemBuilder) {
                         return GridView.builder(
+                          key: gridViewKey,
                           controller: sheetScrollController,
                           gridDelegate: SliverGridDelegateWithFixedCrossAxisCount(
                             //Sync values for itemHeight calculation _calculateItemHeight
@@ -444,11 +455,11 @@ class ViewTabsSheetWidget extends HookConsumerWidget {
                             crossAxisSpacing: 8.0,
                             crossAxisCount: crossAxisCount,
                           ),
-                          itemCount: children.length,
-                          itemBuilder: (context, index) => children[index],
+                          itemCount: tabs.length,
+                          itemBuilder: (context, index) =>
+                              itemBuilder(tabs[index], index),
                         );
                       },
-                      children: tabs,
                     ),
                   );
                 },

app/lib/features/geckoview/features/tabs/data/database/daos/container.dart

@@ -96,4 +96,11 @@ class ContainerDao extends DatabaseAccessor<TabDatabase>
   ) {
     return db.orderKeyAfterTab(containerId: containerId, tabId: tabId);
   }
+
+  SingleSelectable<String> generateOrderKeyBeforeTabId(
+    String? containerId,
+    String tabId,
+  ) {
+    return db.orderKeyBeforeTab(containerId: containerId, tabId: tabId);
+  }
 }

app/lib/features/geckoview/features/tabs/data/database/database.drift

@@ -118,6 +118,18 @@ orderKeyAfterTab(:tab_id AS TEXT, :container_id AS TEXT OR NULL):
   FROM ordered_table
   WHERE id = :tab_id;
 
+orderKeyBeforeTab(:tab_id AS TEXT, :container_id AS TEXT OR NULL):
+  WITH ordered_table AS (
+    SELECT id,
+          order_key,
+          LAG(order_key) OVER (ORDER BY order_key) AS prev_order_key
+    FROM tab 
+    WHERE container_id IS :container_id 
+  )
+  SELECT lexo_rank_reorder_before(order_key, prev_order_key)
+  FROM ordered_table
+  WHERE id = :tab_id;
+
 queryTabsBasic WITH TabQueryResult:
   WITH weights AS (
     SELECT 

app/lib/features/geckoview/features/tabs/data/database/database.g.dart

@@ -83,6 +83,14 @@ class ContainerRepository extends _$ContainerRepository {
         .getSingle();
   }
 
+  Future<String> getOrderKeyBeforeTab(String tabId, String? containerId) {
+    return ref
+        .read(tabDatabaseProvider)
+        .containerDao
+        .generateOrderKeyBeforeTabId(containerId, tabId)
+        .getSingle();
+  }
+
   Future<Color> unusedRandomContainerColor() async {
     final allColors = colorTypes.flattened.toList();
     final usedColors = await getDistinctColors();

app/lib/features/geckoview/features/tabs/domain/repositories/container.dart

@@ -24,7 +24,10 @@ dependencies:
   flutter_material_design_icons: ^1.1.7447
   flutter_mozilla_components:
     path: ../packages/flutter_mozilla_components
-  flutter_reorderable_grid_view: ^5.5.0
+  flutter_reorderable_grid_view: 
+    git:
+      url: https://github.com/FaFre/flutter-reorderable-grid-view.git
+      ref: fix_builder_assert
   flutter_secure_storage: ^10.0.0-beta.4
   flutter_slidable: ^4.0.0
   flutter_svg: ^2.2.0