Migrate assignment module

lib/app/app.dart

@@ -8,7 +8,7 @@ export 'package:hive/hive.dart'
 export 'package:hive_cache/hive_cache.dart';
 export 'package:meta/meta.dart';
 export 'package:pedantic/pedantic.dart';
-export 'package:time_machine/time_machine.dart' show Instant;
+export 'package:time_machine/time_machine.dart' show Instant, LocalDate, Period;
 
 export 'app_config.dart';
 export 'data.dart';

lib/app/services/network.dart

@@ -297,7 +297,7 @@ class NetworkService {
     // ignore: parameter_assignments
     headers = {
       'Content-Type': 'application/json',
-      if (headers != null) ...headers,
+      ...?headers,
     };
     for (final entry in headers.entries) {
       request.headers[entry.key] = entry.value;

lib/assignment/assignment.dart

@@ -1,4 +1,3 @@
 export 'data.dart';
 export 'routes.dart';
-export 'widgets/assignments_screen.dart';
 export 'widgets/dashboard_card.dart';

lib/assignment/pages/assignment_detail_page/page.dart

@@ -0,0 +1,124 @@
+import 'dart:math' as math;
+
+import 'package:flutter/material.dart';
+import 'package:schulcloud/app/app.dart';
+import 'package:schulcloud/course/course.dart';
+
+import '../../data.dart';
+import 'tab_details.dart';
+import 'tab_feedback.dart';
+import 'tab_submission.dart';
+import 'tab_submissions.dart';
+
+class AssignmentDetailPage extends StatefulWidget {
+  const AssignmentDetailPage(this.assignmentId, {this.initialTab})
+      : assert(assignmentId != null);
+
+  final Id<Assignment> assignmentId;
+  final String initialTab;
+
+  @override
+  _AssignmentDetailPageState createState() => _AssignmentDetailPageState();
+}
+
+class _AssignmentDetailPageState extends State<AssignmentDetailPage>
+    with TickerProviderStateMixin {
+  TabController _controller;
+
+  @override
+  Widget build(BuildContext context) {
+    final s = context.s;
+
+    return EntityBuilder<Assignment>(
+      id: widget.assignmentId,
+      builder: handleLoadingError((context, assignment, _) {
+        return EntityBuilder<User>(
+          id: services.storage.userId,
+          builder: handleLoadingError((context, user, fetch) {
+            final showSubmissionTab = assignment.isPrivate || !user.isTeacher;
+            final showFeedbackTab = assignment.isPublic && !user.isTeacher;
+            final showSubmissionsTab = assignment.isPublic &&
+                (user.isTeacher || assignment.hasPublicSubmissions);
+
+            final tabs = [
+              'extended',
+              if (showSubmissionTab) 'submission',
+              if (showFeedbackTab) 'feedback',
+              if (showSubmissionsTab) 'submissions',
+            ];
+            var initialTabIndex = tabs.indexOf(widget.initialTab);
+            if (initialTabIndex < 0) {
+              initialTabIndex = null;
+            }
+
+            if (_controller == null || _controller.length != tabs.length) {
+              _controller = TabController(
+                initialIndex: math.min(initialTabIndex ?? 0, tabs.length - 1),
+                length: tabs.length,
+                vsync: this,
+              );
+            }
+
+            return FancyTabbedScaffold(
+              initialTabIndex: initialTabIndex,
+              controller: _controller,
+              appBarBuilder: (_) => FancyAppBar(
+                title: Text(assignment.name),
+                subtitle: CourseName.orNull(assignment.courseId),
+                actions: <Widget>[
+                  if (user.hasPermission(Permission.assignmentEdit))
+                    _buildArchiveAction(context, assignment),
+                ],
+                bottom: TabBar(
+                  controller: _controller,
+                  tabs: [
+                    Tab(text: s.assignment_assignmentDetails_details),
+                    if (showSubmissionTab)
+                      Tab(text: s.assignment_assignmentDetails_submission),
+                    if (showFeedbackTab)
+                      Tab(text: s.assignment_assignmentDetails_feedback),
+                    if (showSubmissionsTab)
+                      Tab(text: s.assignment_assignmentDetails_submissions),
+                  ],
+                ),
+                // We want a permanent elevation so tabs are more noticeable.
+                forceElevated: true,
+              ),
+              tabs: [
+                DetailsTab(assignment: assignment),
+                if (showSubmissionTab) SubmissionTab(assignment: assignment),
+                if (showFeedbackTab) FeedbackTab(assignment: assignment),
+                if (showSubmissionsTab) SubmissionsTab(),
+              ],
+            );
+          }),
+        );
+      }),
+    );
+  }
+
+  Widget _buildArchiveAction(BuildContext context, Assignment assignment) {
+    final s = context.s;
+
+    return IconButton(
+      icon: Icon(assignment.isArchived ? Icons.unarchive : Icons.archive),
+      tooltip: assignment.isArchived
+          ? s.assignment_assignmentDetails_unarchive
+          : s.assignment_assignmentDetails_archive,
+      onPressed: () async {
+        await assignment.toggleArchived();
+        context.scaffold.showSnackBar(SnackBar(
+          content: Text(
+            assignment.isArchived
+                ? s.assignment_assignmentDetails_unarchived
+                : s.assignment_assignmentDetails_archived,
+          ),
+          action: SnackBarAction(
+            label: s.general_undo,
+            onPressed: assignment.toggleArchived,
+          ),
+        ));
+      },
+    );
+  }
+}

lib/assignment/pages/assignment_detail_page/tab_details.dart

@@ -0,0 +1,85 @@
+import 'package:flutter/material.dart';
+import 'package:schulcloud/app/app.dart';
+
+import '../../data.dart';
+import 'utils.dart';
+
+class DetailsTab extends StatelessWidget {
+  const DetailsTab({Key key, @required this.assignment})
+      : assert(assignment != null),
+        super(key: key);
+
+  final Assignment assignment;
+
+  @override
+  Widget build(BuildContext context) {
+    final textTheme = context.textTheme;
+    final s = context.s;
+
+    final datesText = [
+      s.assignment_assignmentDetails_details_available(
+          assignment.availableAt.longDateTimeString),
+      if (assignment.dueAt != null)
+        s.assignment_assignmentDetails_details_due(
+            assignment.dueAt.longDateTimeString),
+    ].join('\n');
+
+    return TabContent(
+      pageStorageKey: PageStorageKey<String>('details'),
+      omitHorizontalPadding: true,
+      sliver: SliverList(
+        delegate: SliverChildListDelegate.fixed([
+          Padding(
+            padding: EdgeInsets.symmetric(horizontal: 16),
+            child: ChipGroup(children: _buildChips(context)),
+          ),
+          Padding(
+            padding: EdgeInsets.symmetric(horizontal: 16),
+            child: Text(
+              datesText,
+              style: textTheme.bodyText2,
+              textAlign: TextAlign.end,
+            ),
+          ),
+          SizedBox(height: 4),
+          Padding(
+            padding: EdgeInsets.symmetric(horizontal: 16),
+            child: FancyText.rich(assignment.description),
+          ),
+          ...buildFileSection(context, assignment.fileIds),
+        ]),
+      ),
+    );
+  }
+
+  List<Widget> _buildChips(BuildContext context) {
+    final s = context.s;
+
+    return <Widget>[
+      if (assignment.isOverdue)
+        ActionChip(
+          avatar: Icon(
+            Icons.flag,
+            color: context.theme.errorColor,
+          ),
+          label: Text(s.assignment_assignment_overdue),
+          onPressed: () {},
+        ),
+      if (assignment.isArchived)
+        Chip(
+          avatar: Icon(Icons.archive),
+          label: Text(s.assignment_assignment_isArchived),
+        ),
+      if (assignment.isPrivate)
+        Chip(
+          avatar: Icon(Icons.lock),
+          label: Text(s.assignment_assignment_isPrivate),
+        ),
+      if (assignment.hasPublicSubmissions)
+        Chip(
+          avatar: Icon(Icons.public),
+          label: Text(s.assignment_assignment_property_hasPublicSubmissions),
+        ),
+    ];
+  }
+}

lib/assignment/pages/assignment_detail_page/tab_feedback.dart

@@ -0,0 +1,46 @@
+import 'package:flutter/material.dart';
+import 'package:schulcloud/app/app.dart';
+
+import '../../data.dart';
+import '../../widgets/grade_indicator.dart';
+
+class FeedbackTab extends StatelessWidget {
+  const FeedbackTab({Key key, @required this.assignment})
+      : assert(assignment != null),
+        super(key: key);
+
+  final Assignment assignment;
+
+  @override
+  Widget build(BuildContext context) {
+    final s = context.s;
+
+    return ConnectionBuilder.populated<Submission>(
+      connection: assignment.mySubmission,
+      builder: handleLoadingError((context, submission, isFetching) {
+        return TabContent(
+          pageStorageKey: PageStorageKey<String>('feedback'),
+          omitHorizontalPadding: true,
+          sliver: SliverList(
+            delegate: SliverChildListDelegate.fixed([
+              if (submission?.grade != null) ...[
+                ListTile(
+                  leading: GradeIndicator(grade: submission.grade),
+                  title: Text(s.assignment_assignmentDetails_feedback_grade(
+                      submission.grade)),
+                ),
+                SizedBox(height: 8),
+              ],
+              Padding(
+                padding: EdgeInsets.symmetric(horizontal: 16),
+                child: submission?.gradeComment != null
+                    ? FancyText.rich(submission.gradeComment)
+                    : Text(s.assignment_assignmentDetails_feedback_textEmpty),
+              ),
+            ]),
+          ),
+        );
+      }),
+    );
+  }
+}

lib/assignment/pages/assignment_detail_page/tab_submission.dart

@@ -0,0 +1,86 @@
+import 'package:flutter/material.dart';
+import 'package:schulcloud/app/app.dart';
+
+import '../../data.dart';
+import 'utils.dart';
+
+class SubmissionTab extends StatelessWidget {
+  const SubmissionTab({Key key, @required this.assignment})
+      : assert(assignment != null),
+        super(key: key);
+
+  final Assignment assignment;
+
+  @override
+  Widget build(BuildContext context) {
+    return ConnectionBuilder.populated<Submission>(
+      connection: assignment.mySubmission,
+      builder: handleLoadingError((context, submission, isFetching) {
+        // TODO(JonasWanke): differentiate between loading and no submission
+        return Stack(
+          children: <Widget>[
+            TabContent(
+              pageStorageKey: PageStorageKey<String>('submission'),
+              omitHorizontalPadding: true,
+              sliver: _buildContent(context, submission),
+            ),
+            _buildOverlay(context, submission),
+          ],
+        );
+      }),
+    );
+  }
+
+  Widget _buildContent(BuildContext context, Submission submission) {
+    return SliverList(
+      delegate: SliverChildListDelegate([
+        Padding(
+          padding: EdgeInsets.symmetric(horizontal: 16),
+          child: submission == null
+              ? Text(context.s.assignment_assignmentDetails_submission_empty)
+              : FancyText.rich(submission.comment),
+        ),
+        if (submission != null)
+          ...buildFileSection(context, submission.fileIds),
+        if (!assignment.isOverdue) FabSpacer(),
+      ]),
+    );
+  }
+
+  Widget _buildOverlay(BuildContext context, Submission submission) {
+    if (assignment.isOverdue) {
+      return SizedBox.shrink();
+    }
+
+    final s = context.s;
+
+    return EntityBuilder<User>(
+      id: services.storage.userId,
+      builder: handleLoadingError((context, user, isFetching) {
+        String labelText;
+        if (submission == null &&
+            user.hasPermission(Permission.submissionsCreate)) {
+          labelText = s.assignment_assignmentDetails_submission_create;
+        } else if (submission != null &&
+            user.hasPermission(Permission.submissionsEdit)) {
+          labelText = s.assignment_assignmentDetails_submission_edit;
+        }
+        if (labelText == null) {
+          return SizedBox.shrink();
+        }
+
+        return Scaffold(
+          backgroundColor: Colors.transparent,
+          floatingActionButton: Builder(
+            builder: (context) => FloatingActionButton.extended(
+              onPressed: () => context.navigator
+                  .pushNamed('/homework/${assignment.id}/submission'),
+              label: Text(labelText),
+              icon: Icon(Icons.edit),
+            ),
+          ),
+        );
+      }),
+    );
+  }
+}

lib/assignment/pages/assignment_detail_page/tab_submissions.dart

@@ -0,0 +1,21 @@
+import 'package:flutter/material.dart';
+import 'package:schulcloud/app/app.dart';
+
+class SubmissionsTab extends StatelessWidget {
+  const SubmissionsTab({Key key}) : super(key: key);
+
+  @override
+  Widget build(BuildContext context) {
+    return TabContent(
+      pageStorageKey: PageStorageKey<String>('submissions'),
+      sliver: SliverFillRemaining(
+        child: Center(
+          child: Text(
+            context.s.assignment_assignmentDetails_submissions_placeholder,
+            textAlign: TextAlign.center,
+          ),
+        ),
+      ),
+    );
+  }
+}