feat: condivisione piano pasti via QR code

Porta la funzionalità QR code dalla versione Vue a Flutter. Condividi: pulsante in fondo alla tab Pasti (attivo solo con piano non vuoto) → bottom sheet con QR code generato da qr_flutter. Payload: { "v": 1, "meals": { ... } }, limite 2953 byte. Ricevi: pulsante sempre visibile → QrScanPage full-screen con fotocamera via mobile_scanner, cornice di mira, validazione struttura JSON e importazione via MealPlannerProvider.importPlan(). Nuovi package: qr_flutter ^4.1.0, mobile_scanner ^5.0.0 Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
2026-05-17 23:09:16 +02:00
parent 404a5f44ac
commit cebeaf889a
5 changed files with 255 additions and 0 deletions
@@ -0,0 +1,99 @@
+import 'dart:convert';
+import 'package:flutter/material.dart';
+import 'package:qr_flutter/qr_flutter.dart';
+import '../../models/meal_plan.dart';
+
+const int _kQrMaxBytes = 2953;
+
+void showQrShareSheet(BuildContext context, MealPlan plan) {
+  showModalBottomSheet(
+    context: context,
+    isScrollControlled: true,
+    shape: const RoundedRectangleBorder(
+      borderRadius: BorderRadius.vertical(top: Radius.circular(16)),
+    ),
+    builder: (_) => _QrShareSheet(plan: plan),
+  );
+}
+
+class _QrShareSheet extends StatelessWidget {
+  final MealPlan plan;
+  const _QrShareSheet({required this.plan});
+
+  String? _buildPayload() {
+    final payload = jsonEncode({'v': 1, 'meals': plan.days.map(
+      (k, v) => MapEntry(k, {
+        'colazione': v.colazione,
+        'pranzo': v.pranzo,
+        'cena': v.cena,
+      }),
+    )});
+    if (payload.length > _kQrMaxBytes) return null;
+    return payload;
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final payload = _buildPayload();
+    final scheme = Theme.of(context).colorScheme;
+
+    return SafeArea(
+      child: Padding(
+        padding: const EdgeInsets.fromLTRB(20, 12, 20, 32),
+        child: Column(
+          mainAxisSize: MainAxisSize.min,
+          children: [
+            // handle
+            Container(
+              width: 36, height: 4,
+              decoration: BoxDecoration(
+                color: scheme.outlineVariant,
+                borderRadius: BorderRadius.circular(2),
+              ),
+            ),
+            const SizedBox(height: 16),
+            Row(
+              mainAxisAlignment: MainAxisAlignment.spaceBetween,
+              children: [
+                Text('Condividi piano',
+                    style: Theme.of(context)
+                        .textTheme
+                        .titleMedium
+                        ?.copyWith(fontWeight: FontWeight.bold)),
+                IconButton(
+                  icon: const Icon(Icons.close),
+                  onPressed: () => Navigator.pop(context),
+                ),
+              ],
+            ),
+            const SizedBox(height: 4),
+            Text(
+              'Fai scansionare questo codice dall\'altro dispositivo',
+              style: Theme.of(context).textTheme.bodySmall?.copyWith(
+                    color: scheme.onSurfaceVariant,
+                  ),
+            ),
+            const SizedBox(height: 20),
+            if (payload == null)
+              Padding(
+                padding: const EdgeInsets.symmetric(vertical: 24),
+                child: Text(
+                  'Dati troppo grandi per un QR code.\nRiduci il numero di alimenti inseriti.',
+                  textAlign: TextAlign.center,
+                  style: TextStyle(color: scheme.error),
+                ),
+              )
+            else
+              QrImageView(
+                data: payload,
+                version: QrVersions.auto,
+                size: 260,
+                errorCorrectionLevel: QrErrorCorrectLevel.L,
+                backgroundColor: Colors.white,
+              ),
+          ],
+        ),
+      ),
+    );
+  }
+}