feat(app): the path editor in two cards, as before

On the tinted ground, one card holds the path's details (title,
secondary title, a line, the description row, a line, its tags behind an
Add tags chip) and one below holds its steps under their header, lines
between them, filling the window at least.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MMm7usAo6q9ZZRoPkWjoxi
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>

halkyon_learn_flutter/lib/l10n/app_de.arb

@@ -99,6 +99,7 @@
   "pathDescriptionEditTitle": "Pfadbeschreibung",
   "pathAddTags": "Tags hinzufügen",
   "pathTags": "Tags",
+  "pathEditTags": "Tags bearbeiten",
   "pathSteps": "Schritte",
   "pathStepsEmpty": "Noch keine Schritte",
   "pathStepsEmptyHint": "Wähle einen Schritt-Typ, um mit dem Schreiben der Lektion zu beginnen.",

halkyon_learn_flutter/lib/l10n/app_en.arb

@@ -108,6 +108,7 @@
   "pathDescriptionEditTitle": "Path description",
   "pathAddTags": "Add tags",
   "pathTags": "Tags",
+  "pathEditTags": "Edit tags",
   "pathSteps": "Steps",
   "pathStepsEmpty": "No steps yet",
   "pathStepsEmptyHint": "Pick a step type to start writing the lesson.",

halkyon_learn_flutter/lib/l10n/app_localizations.dart

@@ -652,6 +652,12 @@ abstract class AppLocalizations {
   /// **'Tags'**
   String get pathTags;
 
+  /// No description provided for @pathEditTags.
+  ///
+  /// In en, this message translates to:
+  /// **'Edit tags'**
+  String get pathEditTags;
+
   /// No description provided for @pathSteps.
   ///
   /// In en, this message translates to:

halkyon_learn_flutter/lib/l10n/app_localizations_de.dart

@@ -368,6 +368,9 @@ class AppLocalizationsDe extends AppLocalizations {
   @override
   String get pathTags => 'Tags';
 
+  @override
+  String get pathEditTags => 'Tags bearbeiten';
+
   @override
   String get pathSteps => 'Schritte';
 

halkyon_learn_flutter/lib/l10n/app_localizations_en.dart

@@ -365,6 +365,9 @@ class AppLocalizationsEn extends AppLocalizations {
   @override
   String get pathTags => 'Tags';
 
+  @override
+  String get pathEditTags => 'Edit tags';
+
   @override
   String get pathSteps => 'Steps';
 

halkyon_learn_flutter/lib/src/feature/learning_path/widget/path_editor_screen.dart

@@ -1,11 +1,13 @@
 import 'package:flutter_bloc/flutter_bloc.dart';
 import 'package:go_router/go_router.dart';
 import 'package:halkyon_learn_flutter/l10n/app_localizations.dart';
+import 'package:halkyon_learn_flutter/src/core/content/rich_content.dart';
 import 'package:halkyon_learn_flutter/src/core/dependencies/person_scope.dart';
 import 'package:halkyon_learn_flutter/src/core/editor/rich_text_screen.dart';
 import 'package:halkyon_learn_flutter/src/core/layout/readable_width.dart';
 import 'package:halkyon_learn_flutter/src/core/router/route_paths.dart';
 import 'package:halkyon_learn_flutter/src/core/widget/app_loading_indicator.dart';
+import 'package:halkyon_learn_flutter/src/core/widget/section_card.dart';
 import 'package:halkyon_learn_flutter/src/core/widget/undo_snack_bar.dart';
 import 'package:halkyon_learn_flutter/src/feature/learning_path/bloc/path_editor_bloc.dart';
 import 'package:halkyon_learn_flutter/src/feature/learning_path/model/exercise.dart';
@@ -17,9 +19,9 @@ import 'package:lucide_icons_flutter/lucide_icons.dart';
 import 'package:material_ui/material_ui.dart';
 
 /// Writes a learning path of the studyset [studysetId] in the whole window,
-/// over the tabs: its title, secondary title, description and tags, and its
+/// over the tabs: a card of its title, secondary title, description and
-/// steps, added by kind, reordered and deleted with an undo
+/// tags, and a card of its steps, added by kind, reordered and deleted with
-/// (`PathEditorBloc`). A step added opens at once.
+/// an undo (`PathEditorBloc`). A step added opens at once.
 class const PathEditorScreen({
   required final String studysetId,
   required final String pathId,
@@ -61,6 +63,7 @@ class _PathEditorScreenState() extends State<PathEditorScreen> {
         }
       },
       builder: (context, state) => Scaffold(
+        backgroundColor: Theme.of(context).colorScheme.surfaceContainerLow,
         appBar: AppBar(title: Text(l10n.pathEditTitle)),
         body: switch (state) {
           PathEditorState(loaded: false) => const Center(
@@ -86,63 +89,63 @@ class _PathEditorScreenState() extends State<PathEditorScreen> {
     }
   }
 
+  /// The path in two cards on the tinted ground: its details (title,
+  /// secondary title, description, tags), and below them its steps, filling
+  /// the window at least.
   Widget _form(BuildContext context, PathEditorState state) {
     final l10n = AppLocalizations.of(context);
     final theme = Theme.of(context);
     final bloc = context.read<PathEditorBloc>();
-    final description = state.content.description;
     final chosenTags = [
       for (final tag in state.tagging.all)
         if (state.tagIds.contains(tag.id)) tag,
     ];
-    return Align(
+    final label = theme.textTheme.labelMedium?.copyWith(
-      alignment: Alignment.topCenter,
+      color: theme.colorScheme.onSurfaceVariant,
-      child: ConstrainedBox(
+    );
-        constraints: const BoxConstraints(maxWidth: readableContentMaxWidth),
+    final details = SectionCard(
-        child: ListView(
+      padding: EdgeInsets.zero,
-          padding: const EdgeInsets.all(16),
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.stretch,
         children: [
-            TextField(
+          Padding(
+            padding: const EdgeInsets.fromLTRB(16, 8, 16, 0),
+            child: TextField(
               controller: _title,
-              style: theme.textTheme.titleLarge,
+              style: theme.textTheme.headlineSmall,
               decoration: InputDecoration(
-                labelText: l10n.pathTitleLabel,
+                hintText: l10n.pathTitleLabel,
+                border: InputBorder.none,
                 errorText: state.content.title.trim().isEmpty
                     ? l10n.pathTitleRequired
                     : null,
               ),
               onChanged: (text) => bloc.add(PathEditorEventTitleChanged(text)),
             ),
-            const SizedBox(height: 12),
+          ),
-            TextField(
+          Padding(
+            padding: const EdgeInsets.fromLTRB(16, 0, 16, 8),
+            child: TextField(
               controller: _secondary,
+              style: theme.textTheme.titleSmall?.copyWith(
+                color: theme.colorScheme.onSurfaceVariant,
+              ),
               decoration: InputDecoration(
-                labelText: l10n.pathSecondaryTitleLabel,
+                hintText: l10n.pathSecondaryTitleLabel,
-                hintText: l10n.pathSecondaryTitleHint,
+                isDense: true,
+                border: InputBorder.none,
               ),
               onChanged: (text) =>
                   bloc.add(PathEditorEventSecondaryTitleChanged(text)),
             ),
-            const SizedBox(height: 8),
-            ListTile(
-              contentPadding: EdgeInsets.zero,
-              leading: const Icon(LucideIcons.text),
-              title: Text(
-                description.isBlank
-                    ? l10n.pathAddDescription
-                    : l10n.pathDescription,
-              ),
-              subtitle: description.isBlank
-                  ? null
-                  : Text(
-                      description.plainText.trim(),
-                      maxLines: 2,
-                      overflow: TextOverflow.ellipsis,
           ),
+          const Divider(height: 1),
+          _DescriptionRow(
+            description: state.content.description,
             onTap: () async {
               final edited = await editRichText(
                 context,
-                  description,
+                state.content.description,
                 title: l10n.pathDescriptionEditTitle,
               );
               if (edited != null) {
@@ -150,16 +153,26 @@ class _PathEditorScreenState() extends State<PathEditorScreen> {
               }
             },
           ),
+          const Divider(height: 1),
+          Padding(
+            padding: const EdgeInsets.fromLTRB(16, 12, 16, 12),
+            child: Column(
+              crossAxisAlignment: CrossAxisAlignment.start,
+              children: [
+                Text(l10n.pathTags, style: label),
+                const SizedBox(height: 8),
                 Wrap(
                   spacing: 8,
-              runSpacing: 4,
+                  runSpacing: 8,
                   crossAxisAlignment: WrapCrossAlignment.center,
                   children: [
                     for (final tag in chosenTags) TagChip(tag: tag),
-                TextButton.icon(
+                    ActionChip(
-                  icon: const Icon(LucideIcons.tag, size: 16),
+                      avatar: const Icon(LucideIcons.pencil, size: 16),
                       label: Text(
-                    chosenTags.isEmpty ? l10n.pathAddTags : l10n.pathTags,
+                        chosenTags.isEmpty
+                            ? l10n.pathAddTags
+                            : l10n.pathEditTags,
                       ),
                       onPressed: () => showTagPicker(
                         context,
@@ -170,8 +183,20 @@ class _PathEditorScreenState() extends State<PathEditorScreen> {
                     ),
                   ],
                 ),
-            const SizedBox(height: 16),
+              ],
-            Row(
+            ),
+          ),
+        ],
+      ),
+    );
+    final steps = SectionCard(
+      padding: EdgeInsets.zero,
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.stretch,
+        children: [
+          Padding(
+            padding: const EdgeInsets.fromLTRB(16, 8, 8, 8),
+            child: Row(
               children: [
                 Expanded(
                   child: Text(
@@ -204,16 +229,14 @@ class _PathEditorScreenState() extends State<PathEditorScreen> {
                 ),
               ],
             ),
-            const SizedBox(height: 8),
+          ),
+          const Divider(height: 1),
           if (state.steps.isEmpty)
             Padding(
-                padding: const EdgeInsets.symmetric(vertical: 24),
+              padding: const EdgeInsets.all(24),
               child: Column(
                 children: [
-                    Text(
+                  Text(l10n.pathStepsEmpty, style: theme.textTheme.titleSmall),
-                      l10n.pathStepsEmpty,
-                      style: theme.textTheme.titleSmall,
-                    ),
                   const SizedBox(height: 4),
                   Text(
                     l10n.pathStepsEmptyHint,
@@ -246,9 +269,9 @@ class _PathEditorScreenState() extends State<PathEditorScreen> {
               ],
             )
           else
-              for (final step in state.steps)
+            for (final (index, step) in state.steps.indexed) ...[
+              if (index > 0) const Divider(height: 1),
               ListTile(
-                  contentPadding: EdgeInsets.zero,
                 leading: Icon(stepKindIcon(step.kind)),
                 title: _StepTitle(step: step),
                 subtitle: Text(stepKindLabel(l10n, step.kind)),
@@ -262,13 +285,35 @@ class _PathEditorScreenState() extends State<PathEditorScreen> {
                 trailing: IconButton(
                   icon: Icon(
                     LucideIcons.trash2,
-                      color: Theme.of(context).colorScheme.error,
+                    color: theme.colorScheme.error,
                   ),
                   tooltip: l10n.pathStepDelete,
                   onPressed: () => _deleteStep(context, step),
                 ),
               ),
             ],
+        ],
+      ),
+    );
+    return Align(
+      alignment: Alignment.topCenter,
+      child: ConstrainedBox(
+        constraints: const BoxConstraints(maxWidth: readableContentMaxWidth),
+        child: CustomScrollView(
+          slivers: [
+            SliverPadding(
+              padding: const EdgeInsets.fromLTRB(12, 8, 12, 12),
+              sliver: SliverToBoxAdapter(child: details),
+            ),
+            // Padded inside: the sliver fills to the window's edge.
+            SliverFillRemaining(
+              hasScrollBody: false,
+              child: Padding(
+                padding: const EdgeInsets.fromLTRB(12, 0, 12, 12),
+                child: steps,
+              ),
+            ),
+          ],
         ),
       ),
     );
@@ -286,6 +331,54 @@ class _PathEditorScreenState() extends State<PathEditorScreen> {
   }
 }
 
+/// The path's description, a few lines of it or an invitation to write
+/// one, opening its editor.
+class const _DescriptionRow({
+  required final RichContent description,
+  required final VoidCallback onTap,
+}) extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    final l10n = AppLocalizations.of(context);
+    final theme = Theme.of(context);
+    final muted = theme.colorScheme.onSurfaceVariant;
+    final text = description.plainText.trim();
+    return InkWell(
+      onTap: onTap,
+      child: Padding(
+        padding: const EdgeInsets.fromLTRB(16, 12, 12, 12),
+        child: Row(
+          children: [
+            Expanded(
+              child: Column(
+                crossAxisAlignment: CrossAxisAlignment.start,
+                children: [
+                  Text(
+                    l10n.pathDescription,
+                    style: theme.textTheme.labelMedium?.copyWith(color: muted),
+                  ),
+                  const SizedBox(height: 4),
+                  Text(
+                    text.isEmpty ? l10n.pathAddDescription : text,
+                    maxLines: 3,
+                    overflow: TextOverflow.ellipsis,
+                    style: theme.textTheme.bodyMedium?.copyWith(
+                      color: text.isEmpty ? muted : null,
+                      fontStyle: text.isEmpty ? FontStyle.italic : null,
+                    ),
+                  ),
+                ],
+              ),
+            ),
+            const SizedBox(width: 8),
+            Icon(LucideIcons.chevronRight, size: 18, color: muted),
+          ],
+        ),
+      ),
+    );
+  }
+}
+
 /// A step's title, or "Untitled step".
 class const _StepTitle({required final LearningPathStep step})
     extends StatelessWidget {

halkyon_learn_flutter/test/feature/learning_path/widget/path_screens_test.dart

@@ -6,6 +6,7 @@ import 'package:halkyon_learn_flutter/src/core/citation/model/source.dart';
 import 'package:halkyon_learn_flutter/src/core/content/rich_content.dart';
 import 'package:halkyon_learn_flutter/src/core/device_settings/model/device_settings.dart';
 import 'package:halkyon_learn_flutter/src/core/router/route_paths.dart';
+import 'package:halkyon_learn_flutter/src/core/widget/section_card.dart';
 import 'package:halkyon_learn_flutter/src/feature/learning_path/data/learning_path_repository.dart';
 import 'package:halkyon_learn_flutter/src/feature/learning_path/model/exercise.dart';
 import 'package:halkyon_learn_flutter/src/feature/learning_path/model/learning_path.dart';
@@ -186,6 +187,33 @@ void main() {
     expect(find.text('Which one?'), findsOneWidget);
   });
 
+  testWidgets("the path editor groups the path's details in one card and its "
+      'steps in another, filling the window below', (tester) async {
+    final paths = repository();
+    final id = await paths.createPath(
+      'japanese',
+      LearningPathContent.titled('Particles'),
+    );
+    await paths.createStep(id, StepKind.info, step(StepKind.info, 'Read'));
+    await showApp(tester, RoutePaths.editPath('japanese', id));
+
+    final cards = find.byType(SectionCard);
+    expect(cards, findsNWidgets(2));
+    Finder inCard(int index, Finder part) =>
+        find.descendant(of: cards.at(index), matching: part);
+    for (final part in ['Particles', 'Description', 'Add a description']) {
+      expect(inCard(0, find.text(part)), findsOneWidget, reason: part);
+    }
+    expect(inCard(0, find.widgetWithText(ActionChip, 'Add tags')), findsOne);
+    for (final part in ['Steps', 'Add step', 'Read']) {
+      expect(inCard(1, find.text(part)), findsOneWidget, reason: part);
+    }
+    expect(
+      tester.getRect(cards.at(1)).bottom,
+      moreOrLessEquals(1000 - 12, epsilon: 1),
+    );
+  });
+
   testWidgets('imports a path from a file, saying what came in and what was '
       'left out', (tester) async {
     files.next = (