added guardian letters with chat and multiple answer functionalities

2026-09-20 16:12:45 +02:00
parent 67c935c05b
commit 2423c1a75e
68 changed files with 8348 additions and 226 deletions
@@ -0,0 +1,125 @@
+import 'dart:typed_data';
+
+import 'package:flutter/material.dart';
+import 'package:signature/signature.dart';
+
+import '../../../../widget/info_dialog.dart';
+
+/// Upper bound the server accepts for a signature image.
+const int maxSignatureBytes = 256 * 1024;
+
+/// Lets the guardian draw a signature. Resolves to the PNG (transparent
+/// background, cropped to the strokes) or null when dismissed.
+Future<Uint8List?> showSignatureSheet(
+  BuildContext context, {
+  required String signerHint,
+}) => showModalBottomSheet<Uint8List>(
+  context: context,
+  isScrollControlled: true,
+  enableDrag: false,
+  showDragHandle: false,
+  builder: (_) => _SignatureSheet(signerHint: signerHint),
+);
+
+class _SignatureSheet extends StatefulWidget {
+  final String signerHint;
+
+  const _SignatureSheet({required this.signerHint});
+
+  @override
+  State<_SignatureSheet> createState() => _SignatureSheetState();
+}
+
+class _SignatureSheetState extends State<_SignatureSheet> {
+  // Paper-like pad in both themes: what is drawn is what gets exported.
+  final SignatureController _controller = SignatureController(
+    penStrokeWidth: 2.5,
+    penColor: Colors.black,
+    strokeCap: StrokeCap.round,
+    strokeJoin: StrokeJoin.round,
+  );
+
+  @override
+  void initState() {
+    super.initState();
+    _controller.addListener(_onChanged);
+  }
+
+  bool _isEmpty = true;
+
+  // The controller notifies per drawn point; only the buttons depend on it.
+  void _onChanged() {
+    if (_controller.isEmpty == _isEmpty) return;
+    setState(() => _isEmpty = _controller.isEmpty);
+  }
+
+  @override
+  void dispose() {
+    _controller.removeListener(_onChanged);
+    _controller.dispose();
+    super.dispose();
+  }
+
+  Future<void> _accept() async {
+    var png = await _controller.toPngBytes();
+    if (png != null && png.lengthInBytes > maxSignatureBytes) {
+      png = await _controller.toPngBytes(width: 600);
+    }
+    if (!mounted) return;
+    if (png == null || png.lengthInBytes > maxSignatureBytes) {
+      InfoDialog.show(
+        context,
+        'Die Unterschrift konnte nicht übernommen werden. Bitte versuche es '
+        'erneut.',
+        title: 'Unterschrift',
+      );
+      return;
+    }
+    Navigator.pop(context, png);
+  }
+
+  @override
+  Widget build(BuildContext context) => SafeArea(
+    child: Padding(
+      padding: const EdgeInsets.fromLTRB(16, 16, 16, 8),
+      child: Column(
+        mainAxisSize: MainAxisSize.min,
+        crossAxisAlignment: CrossAxisAlignment.stretch,
+        children: [
+          Text('Unterschrift', style: Theme.of(context).textTheme.titleLarge),
+          const SizedBox(height: 4),
+          Text(widget.signerHint),
+          const SizedBox(height: 12),
+          ClipRRect(
+            borderRadius: BorderRadius.circular(12),
+            child: Signature(
+              controller: _controller,
+              height: 220,
+              backgroundColor: Colors.white,
+            ),
+          ),
+          const SizedBox(height: 8),
+          Row(
+            children: [
+              TextButton.icon(
+                onPressed: _isEmpty ? null : _controller.clear,
+                icon: const Icon(Icons.undo),
+                label: const Text('Löschen'),
+              ),
+              const Spacer(),
+              TextButton(
+                onPressed: () => Navigator.pop(context),
+                child: const Text('Abbrechen'),
+              ),
+              const SizedBox(width: 8),
+              FilledButton(
+                onPressed: _isEmpty ? null : _accept,
+                child: const Text('Übernehmen'),
+              ),
+            ],
+          ),
+        ],
+      ),
+    ),
+  );
+}