docs(qa): mark P1 issues 1-3 as resolved

README.md

@@ -2,56 +2,67 @@
 
 Prototype Flutter app for generating bottle-cap mosaics from imported images.
 
-## Implemented MVP
+## Features
 
 - Import target image from gallery (`image_picker`)
 - Resolution controls:
   - explicit grid width/height
   - or auto grid by approximate cap size in source image pixels
-- Cap palette management:
+- Persistent **Cap Catalog** (local JSON in app documents directory):
-  - list caps with name + color
+  - each entry stores `name`, `color` (hex/swatch), and optional preview image path
-  - add color via picker and/or manual hex
+  - survives app restarts
-  - remove caps
+- Catalog management:
-- Mosaic generation:
+  - add entries manually (name + hex/color picker + optional photo)
-  - resize source to grid
+  - **Deckel fotografieren**: robust circular cap detection (edge-based circle search with fallback), color is computed only from masked cap interior pixels
-  - nearest cap color match using CIELAB + DeltaE (CIE76)
+  - selectable extraction mode in photo review dialog: **Dominante Farbe** or **Durchschnitt**
-  - fallback concept is RGB distance, but LAB path is implemented directly
+  - dedicated catalog browser with **list/grid** modes
-- Output:
+  - edit existing entry name/color
-  - mosaic grid preview
+  - delete entries (with thumbnail cleanup)
-  - bill of materials counts per cap color
+- Mosaic preview + bill of materials counts per cap color
+- Mosaic palette source is always the current catalog entries
 
-## Current blocker on this machine
+## Style controls (new)
 
-`flutter` SDK is not installed (`flutter: command not found`), so I could not run:
+User-facing controls are integrated directly in the main screen:
 
-- `flutter create`
+- **Fidelity ↔ Structure** slider
-- `flutter pub get`
+  - fidelity side keeps direct color faithfulness
-- `flutter analyze`
+  - structure side applies edge-aware smoothing for cleaner large forms
-- `flutter build apk --debug`
+- **Dithering strength** slider
+  - scales Floyd–Steinberg error diffusion
+- **Edge emphasis** slider
+  - boosts edge readability during color assignment
+- **Color tolerance / variation** slider
+  - allows controlled variation among similar cap colors in flatter regions
 
-## Setup commands (Ubuntu/Debian)
+## Presets
+
+Three presets are provided and selectable via segmented buttons:
+
+- **Realistisch**
+- **Ausgewogen**
+- **Künstlerisch**
+
+Selecting a preset sets all four style controls at once.
+
+## Pipeline notes
+
+The generation pipeline still uses fast CIELAB (`DeltaE CIE76`) nearest-color matching,
+with precomputed palette LAB values, LAB caching, and low-cost edge-aware processing to keep performance responsive.
+
+## Build (arm64 split debug)
 
 ```bash
-cd /home/yadciel/.openclaw/workspace
-sudo snap install flutter --classic
-# OR: install manually from flutter.dev and add to PATH
-
-flutter doctor
-
 cd /home/yadciel/.openclaw/workspace/korken_mosaic
-flutter create .
 flutter pub get
-flutter run
+flutter build apk --debug --split-per-abi
-flutter build apk --debug
 ```
 
-Expected APK artifact:
+Expected arm64 artifact:
 
-`build/app/outputs/flutter-apk/app-debug.apk`
+`build/app/outputs/flutter-apk/app-arm64-v8a-debug.apk`
 
-## Project files
+## Main files
 
-- `lib/main.dart` – complete MVP UI + mosaic logic
+- `lib/main.dart` – UI + mosaic logic
-- `pubspec.yaml` – dependencies
+- `README.md` – overview and build instructions
-- `analysis_options.yaml`
-- `.gitignore`

android/app/src/main/AndroidManifest.xml

@@ -0,0 +1,47 @@
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+    <uses-permission android:name="android.permission.CAMERA" />
+
+    <application
+        android:label="korken_mosaic"
+        android:name="${applicationName}"
+        android:icon="@mipmap/ic_launcher">
+        <activity
+            android:name=".MainActivity"
+            android:exported="true"
+            android:launchMode="singleTop"
+            android:taskAffinity=""
+            android:theme="@style/LaunchTheme"
+            android:configChanges="orientation|keyboardHidden|keyboard|screenSize|smallestScreenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"
+            android:hardwareAccelerated="true"
+            android:windowSoftInputMode="adjustResize">
+            <!-- Specifies an Android theme to apply to this Activity as soon as
+                 the Android process has started. This theme is visible to the user
+                 while the Flutter UI initializes. After that, this theme continues
+                 to determine the Window background behind the Flutter UI. -->
+            <meta-data
+              android:name="io.flutter.embedding.android.NormalTheme"
+              android:resource="@style/NormalTheme"
+              />
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN"/>
+                <category android:name="android.intent.category.LAUNCHER"/>
+            </intent-filter>
+        </activity>
+        <!-- Don't delete the meta-data below.
+             This is used by the Flutter tool to generate GeneratedPluginRegistrant.java -->
+        <meta-data
+            android:name="flutterEmbedding"
+            android:value="2" />
+    </application>
+    <!-- Required to query activities that can process text, see:
+         https://developer.android.com/training/package-visibility and
+         https://developer.android.com/reference/android/content/Intent#ACTION_PROCESS_TEXT.
+
+         In particular, this is used by the Flutter engine in io.flutter.plugin.text.ProcessTextPlugin. -->
+    <queries>
+        <intent>
+            <action android:name="android.intent.action.PROCESS_TEXT"/>
+            <data android:mimeType="text/plain"/>
+        </intent>
+    </queries>
+</manifest>

docs/qa/issues-20260224.md

@@ -0,0 +1,136 @@
+# QA Issues – 2026-02-24
+
+Scope: Agentische, statische QA-Review (Flutter/Dart CLI lokal nicht verfügbar: `flutter` fehlt). Fokus auf 4-Step-Flow, Save/Load/Delete, JSON-Export und UX-Kantenfälle.
+
+## Issue 1 (P1) – 4-Step-Flow lässt Fortschritt ohne Pflichtdaten zu ✅ ERLEDIGT (feat/mosaic-stepper-export)
+**Bereich:** 4-Step-Flow
+
+**Beobachtung**
+- Im `Stepper` kann man per `Weiter`/Tap bis Schritt 4 springen, auch ohne Bildauswahl.
+- Auf Schritt 4 ist „Generate Mosaic“ aktiv, aber `_generate()` bricht stillschweigend ab, wenn kein Bild vorhanden ist.
+
+**Code-Hinweis**
+- `lib/main.dart:1068-1127` (`Stepper` ohne Guard/Validation)
+- `lib/main.dart:1250-1255` (Generate-Button nur an `_isGenerating` gebunden)
+- `lib/main.dart:884`ff (`_generate()` returnt bei `_sourceImageBytes == null` ohne User-Feedback)
+
+**Repro-Schritte**
+1. App öffnen (kein Bild geladen).
+2. Im Mosaic-Stepper mehrfach „Weiter“ klicken oder direkt auf Schritt 4 tippen.
+3. „Generate Mosaic“ klicken.
+4. Es passiert visuell nichts (kein Ergebnis, kein Hinweis).
+
+**Akzeptanzkriterium**
+- Schritt-Navigation ist zustandsbasiert: Schritt 2-4 erst zugänglich, wenn notwendige Voraussetzungen erfüllt sind.
+- „Generate Mosaic“ ist deaktiviert, solange kein Bild geladen ist.
+- Alternativ/zusätzlich: verständliche Fehlermeldung (Snackbar), falls Generierung ohne Bild ausgelöst wird.
+
+---
+
+## Issue 2 (P1) – Projekt-Load mit leerem Bild leert bestehenden Zustand nicht ✅ ERLEDIGT (feat/mosaic-stepper-export)
+**Bereich:** Save/Load-Flow
+
+**Beobachtung**
+- Beim Laden werden `_sourceImageBytes` und `_result` nur gesetzt, wenn `data.sourceImageBytes != null`.
+- Lädt man ein Projekt ohne Bild, bleibt ggf. ein altes Bild/Ergebnis aus vorherigem Zustand erhalten.
+
+**Code-Hinweis**
+- `lib/main.dart:308-313` (fehlender `else`-Zweig zum expliziten Zurücksetzen)
+
+**Repro-Schritte**
+1. Projekt A mit Bild laden/generieren.
+2. Projekt B laden, das ohne Bild gespeichert wurde (oder manuell erstellt wurde).
+3. Erwartung: leerer/initialer Zustand.
+4. Ist-Zustand: vorheriges Bild kann bestehen bleiben.
+
+**Akzeptanzkriterium**
+- Beim Laden eines Projekts ohne `sourceImageBytes` wird Zustand explizit zurückgesetzt (`_sourceImageBytes = null`, `_result = null`, ggf. Step auf 1).
+- UI zeigt konsistent den tatsächlich geladenen Projektzustand.
+
+---
+
+## Issue 3 (P1) – Projekt-Snapshots sind nicht reproduzierbar, da Katalog nicht versioniert wird ✅ ERLEDIGT (feat/mosaic-stepper-export)
+**Bereich:** Save/Load-Flow + JSON-Export
+
+**Beobachtung**
+- Gespeicherte Projekte enthalten Parameter + Bild, aber **keinen Snapshot des verwendeten Farb-Katalogs**.
+- Beim Laden wird mit aktuellem globalen `_catalog` neu generiert → Ergebnis kann von ursprünglichem Snapshot abweichen.
+
+**Code-Hinweis**
+- `lib/project_codec.dart` (`MosaicProjectData` ohne Katalogdaten)
+- `lib/main.dart:316` (`_generate()` nach Load nutzt aktuellen `_catalog`)
+
+**Repro-Schritte**
+1. Mit Katalog-Set A ein Projekt erzeugen/speichern.
+2. Katalogfarben ändern (hinzufügen/löschen/umfärben).
+3. Projekt laden.
+4. Ergebnisfarben/Zuordnung unterscheiden sich vom ursprünglichen Stand.
+
+**Akzeptanzkriterium**
+- Projektspeicherung enthält eine Palette/Katalog-Snapshot-Version (mind. Name + Farbe pro Eintrag).
+- Load nutzt standardmäßig den gespeicherten Snapshot (mit klarer UX bei Konflikten/Optionen).
+- Reproduzierbarkeit des Mosaiks ist gewährleistet.
+
+---
+
+## Issue 4 (P2) – Export JSON nicht klar reproduzierbar ohne Ergebnis
+**Bereich:** JSON-Export
+
+**Beobachtung**
+- Export enthält `project` immer, `result` aber nur falls bereits generiert.
+- Wenn vor Export keine Generierung lief, fehlt Kerninformation (`assignments`/`palette`) ohne klaren Nutzerhinweis.
+
+**Code-Hinweis**
+- `lib/main.dart:378-392`
+
+**Repro-Schritte**
+1. Bild laden, aber nicht generieren.
+2. „Export JSON“ klicken.
+3. Exportdatei enthält kein `result`-Objekt.
+
+**Akzeptanzkriterium**
+- UX-Entscheidung explizit umsetzen:
+  - entweder Export-Button nur mit vorhandenem Ergebnis aktivieren, oder
+  - vor Export automatisch generieren, oder
+  - deutlichen Hinweisdialog anzeigen („Export ohne Ergebnisdaten“).
+
+---
+
+## Issue 5 (P3) – „Fertig“-CTA im letzten Step ohne klaren Effekt
+**Bereich:** 4-Step-Flow UX
+
+**Beobachtung**
+- Im letzten Step zeigt der Continue-Button „Fertig“, führt aber funktional zu keiner sichtbaren Aktion.
+
+**Code-Hinweis**
+- `lib/main.dart:1071-1093` (`onStepContinue` erhöht nur bis max. letztem Step)
+
+**Repro-Schritte**
+1. Bis Schritt 4 navigieren.
+2. „Fertig“ klicken.
+3. Kein Abschluss-Feedback/State-Change.
+
+**Akzeptanzkriterium**
+- Letzter CTA hat klare Bedeutung (z. B. „Generieren“, „Abschließen“, „Zum Export“) oder wird im letzten Step ausgeblendet.
+- Nutzer erhält eindeutiges Abschlussfeedback.
+
+---
+
+## Issue 6 (P3) – Lösch-Flow ohne Hinweis auf betroffenen Arbeitsstand
+**Bereich:** Delete-Flow UX
+
+**Beobachtung**
+- Beim Löschen eines Snapshots gibt es nur Dateiname + Bestätigung.
+- Kein Hinweis, ob gerade geladener Stand betroffen ist bzw. wie sich das auf „Letzten Stand laden“ auswirkt.
+
+**Code-Hinweis**
+- `lib/main.dart:333-367`
+
+**Repro-Schritte**
+1. Snapshot laden.
+2. In Projekte denselben Snapshot löschen.
+3. Nutzer bleibt ohne Kontext, ob aktiver Stand/Latest-Verhalten beeinflusst ist.
+
+**Akzeptanzkriterium**
+- Dialog/Feedback benennt Auswirkungen klar (z. B. „Aktuell geladener Zustand bleibt im Speicher bis Wechsel/Neustart“).
+- Optional: Markierung des aktuell geladenen Snapshots in der Liste.

docs/review/review-20260224.md

@@ -0,0 +1,52 @@
+# Code Review – Änderungen von `814705c` bis `HEAD` (`ab7aa62`)
+
+## 1) High-risk Findings
+
+### Keine blocker-kritischen Defekte gefunden
+Ich habe im betrachteten Commit keine eindeutigen Crash-/Datenverlust-Blocker gefunden, die einen sofortigen Release-Stopp erzwingen.
+
+> Hinweis: Es gibt aber eine **relevante funktionale Regression** (siehe Nitpicks #1), die je nach Produktanforderung als Go/No-Go-Kriterium gewertet werden kann.
+
+---
+
+## 2) Nitpicks / Verbesserungen
+
+1. **Funktionale Regression in der UI (ehemals 4 Style-Regler, jetzt nur noch 1 sichtbar)**  
+   In `lib/main.dart` zeigt `_buildColorStep()` nur noch den Slider `fidelityStructure`.  
+   Die bisherigen Feineinstellungen `ditheringStrength`, `edgeEmphasis`, `colorVariation` sind weiter im State/Codec vorhanden, aber nicht mehr direkt im UI editierbar.  
+   **Impact:** Nutzer verlieren granulare Qualitätskontrolle; gespeicherte Werte bleiben zwar erhalten, sind aber kaum noch aktiv manipulierbar.
+
+2. **Stepper-Logik ohne Validierung / Guidance**  
+   `onStepContinue` lässt das Voranschreiten ohne notwendige Preconditions zu (z. B. ohne Bildauswahl bis Schritt 4). Das ist technisch robust (Generate guarded), aber UX-seitig irreführend.  
+   **Vorschlag:** Continue-Button je Schritt konditional deaktivieren oder klare Inline-Hinweise anzeigen.
+
+3. **`Fertig`-Button im letzten Step ohne echte Aktion**  
+   In `controlsBuilder` wird im letzten Schritt der Label-Text auf `Fertig` gesetzt, aber `onStepContinue` führt dort effektiv nichts mehr aus.  
+   **Vorschlag:** Auf letzter Stufe Button ausblenden oder mit sinnvoller Aktion belegen (z. B. Export, Speichern, Zur Projektliste).
+
+4. **Projekt-Ladesemantik setzt immer auf Step `result`**  
+   Beim Laden mit Bild springt der Flow direkt auf `MosaicFlowStep.result`. Das ist für „Quick resume“ okay, nimmt aber ggf. den Guided-Flow-Charakter.  
+   **Vorschlag:** Optionales Verhalten (z. B. Restore des letzten Steps oder Konfiguration `resumeAtResult`).
+
+5. **Testabdeckung für neue Kernpfade noch dünn**  
+   Es gibt gute Basis-Tests (`project_codec_test`, einfacher Stepper-Smoke-Test), aber es fehlen Tests für:
+   - latest/autosave-Verhalten (`latest_project.json`),
+   - manuell vs. automatisch speichern,
+   - Export-JSON-Struktur inkl. Result-Payload,
+   - Laden aus Snapshot vs. latest.
+
+---
+
+## 3) Go/No-Go Empfehlung
+
+**Empfehlung: GO mit Auflagen (kein Hard No-Go).**
+
+Begründung:
+- Die neuen Features (4-Step-Flow, autosave/latest, JSON-Export, Bestätigungsdialog beim Löschen) sind grundsätzlich sinnvoll umgesetzt.
+- Kein klarer, reproduzierbarer Blocker im Diff erkennbar.
+- Vor Release sollten jedoch mindestens die UX-/Funktionsregressionspunkte (insb. fehlende 3 Style-Regler) bewusst entschieden/fixiert werden.
+
+**Release-Auflagen (kurz):**
+1. Entscheiden/fixen, ob die 3 fehlenden Style-Regler absichtliche Scope-Reduktion oder Regression sind.  
+2. Stepper-UX (Continue/Finish-Verhalten) konsistenter machen.  
+3. 2–3 gezielte Tests für Save/Load/Export-Pfade ergänzen.

ios/Runner/Info.plist

@@ -0,0 +1,72 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>CADisableMinimumFrameDurationOnPhone</key>
+	<true/>
+	<key>CFBundleDevelopmentRegion</key>
+	<string>$(DEVELOPMENT_LANGUAGE)</string>
+	<key>CFBundleDisplayName</key>
+	<string>Korken Mosaic</string>
+	<key>CFBundleExecutable</key>
+	<string>$(EXECUTABLE_NAME)</string>
+	<key>CFBundleIdentifier</key>
+	<string>$(PRODUCT_BUNDLE_IDENTIFIER)</string>
+	<key>CFBundleInfoDictionaryVersion</key>
+	<string>6.0</string>
+	<key>CFBundleName</key>
+	<string>korken_mosaic</string>
+	<key>CFBundlePackageType</key>
+	<string>APPL</string>
+	<key>CFBundleShortVersionString</key>
+	<string>$(FLUTTER_BUILD_NAME)</string>
+	<key>CFBundleSignature</key>
+	<string>????</string>
+	<key>CFBundleVersion</key>
+	<string>$(FLUTTER_BUILD_NUMBER)</string>
+	<key>LSRequiresIPhoneOS</key>
+	<true/>
+	<key>NSCameraUsageDescription</key>
+	<string>Die Kamera wird verwendet, um einen Flaschendeckel für die Farbpalette zu fotografieren.</string>
+	<key>UIApplicationSceneManifest</key>
+	<dict>
+		<key>UIApplicationSupportsMultipleScenes</key>
+		<false/>
+		<key>UISceneConfigurations</key>
+		<dict>
+			<key>UIWindowSceneSessionRoleApplication</key>
+			<array>
+				<dict>
+					<key>UISceneClassName</key>
+					<string>UIWindowScene</string>
+					<key>UISceneConfigurationName</key>
+					<string>flutter</string>
+					<key>UISceneDelegateClassName</key>
+					<string>$(PRODUCT_MODULE_NAME).SceneDelegate</string>
+					<key>UISceneStoryboardFile</key>
+					<string>Main</string>
+				</dict>
+			</array>
+		</dict>
+	</dict>
+	<key>UIApplicationSupportsIndirectInputEvents</key>
+	<true/>
+	<key>UILaunchStoryboardName</key>
+	<string>LaunchScreen</string>
+	<key>UIMainStoryboardFile</key>
+	<string>Main</string>
+	<key>UISupportedInterfaceOrientations</key>
+	<array>
+		<string>UIInterfaceOrientationPortrait</string>
+		<string>UIInterfaceOrientationLandscapeLeft</string>
+		<string>UIInterfaceOrientationLandscapeRight</string>
+	</array>
+	<key>UISupportedInterfaceOrientations~ipad</key>
+	<array>
+		<string>UIInterfaceOrientationPortrait</string>
+		<string>UIInterfaceOrientationPortraitUpsideDown</string>
+		<string>UIInterfaceOrientationLandscapeLeft</string>
+		<string>UIInterfaceOrientationLandscapeRight</string>
+	</array>
+</dict>
+</plist>

lib/project_codec.dart

@@ -0,0 +1,95 @@
+import 'dart:convert';
+import 'dart:typed_data';
+
+class MosaicPaletteSnapshotEntry {
+  final String name;
+  final int colorValue;
+
+  const MosaicPaletteSnapshotEntry({
+    required this.name,
+    required this.colorValue,
+  });
+
+  Map<String, dynamic> toJson() => {
+        'name': name,
+        'colorValue': colorValue,
+      };
+
+  factory MosaicPaletteSnapshotEntry.fromJson(Map<String, dynamic> json) {
+    return MosaicPaletteSnapshotEntry(
+      name: json['name'] as String? ?? 'Unbenannt',
+      colorValue: (json['colorValue'] as num?)?.toInt() ?? 0xFF000000,
+    );
+  }
+}
+
+class MosaicProjectData {
+  final bool useCapSize;
+  final String gridWidth;
+  final String gridHeight;
+  final String capSize;
+  final double fidelityStructure;
+  final double ditheringStrength;
+  final double edgeEmphasis;
+  final double colorVariation;
+  final String selectedPreset;
+  final Uint8List? sourceImageBytes;
+  final List<MosaicPaletteSnapshotEntry> catalogSnapshot;
+  final DateTime savedAt;
+
+  const MosaicProjectData({
+    required this.useCapSize,
+    required this.gridWidth,
+    required this.gridHeight,
+    required this.capSize,
+    required this.fidelityStructure,
+    required this.ditheringStrength,
+    required this.edgeEmphasis,
+    required this.colorVariation,
+    required this.selectedPreset,
+    required this.sourceImageBytes,
+    required this.catalogSnapshot,
+    required this.savedAt,
+  });
+
+  Map<String, dynamic> toJson() => {
+        'useCapSize': useCapSize,
+        'gridWidth': gridWidth,
+        'gridHeight': gridHeight,
+        'capSize': capSize,
+        'fidelityStructure': fidelityStructure,
+        'ditheringStrength': ditheringStrength,
+        'edgeEmphasis': edgeEmphasis,
+        'colorVariation': colorVariation,
+        'selectedPreset': selectedPreset,
+        'sourceImageBase64':
+            sourceImageBytes == null ? null : base64Encode(sourceImageBytes!),
+        'catalogSnapshot': catalogSnapshot.map((entry) => entry.toJson()).toList(),
+        'savedAt': savedAt.toIso8601String(),
+      };
+
+  factory MosaicProjectData.fromJson(Map<String, dynamic> json) {
+    final sourceB64 = json['sourceImageBase64'] as String?;
+    final snapshotRaw = (json['catalogSnapshot'] as List?) ?? const [];
+    return MosaicProjectData(
+      useCapSize: json['useCapSize'] as bool? ?? false,
+      gridWidth: json['gridWidth'] as String? ?? '40',
+      gridHeight: json['gridHeight'] as String? ?? '30',
+      capSize: json['capSize'] as String? ?? '12',
+      fidelityStructure: (json['fidelityStructure'] as num?)?.toDouble() ?? 0.5,
+      ditheringStrength:
+          (json['ditheringStrength'] as num?)?.toDouble() ?? 0.35,
+      edgeEmphasis: (json['edgeEmphasis'] as num?)?.toDouble() ?? 0.4,
+      colorVariation: (json['colorVariation'] as num?)?.toDouble() ?? 0.3,
+      selectedPreset: json['selectedPreset'] as String? ?? 'ausgewogen',
+      sourceImageBytes: sourceB64 == null ? null : base64Decode(sourceB64),
+      catalogSnapshot: snapshotRaw
+          .whereType<Map>()
+          .map((entry) => MosaicPaletteSnapshotEntry.fromJson(
+              Map<String, dynamic>.from(entry)))
+          .toList(growable: false),
+      savedAt:
+          DateTime.tryParse(json['savedAt'] as String? ?? '') ?? DateTime.now(),
+    );
+  }
+}

pubspec.lock

@@ -0,0 +1,578 @@
+# Generated by pub
+# See https://dart.dev/tools/pub/glossary#lockfile
+packages:
+  archive:
+    dependency: transitive
+    description:
+      name: archive
+      sha256: a96e8b390886ee8abb49b7bd3ac8df6f451c621619f52a26e815fdcf568959ff
+      url: "https://pub.dev"
+    source: hosted
+    version: "4.0.9"
+  async:
+    dependency: transitive
+    description:
+      name: async
+      sha256: "758e6d74e971c3e5aceb4110bfd6698efc7f501675bcfe0c775459a8140750eb"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.13.0"
+  boolean_selector:
+    dependency: transitive
+    description:
+      name: boolean_selector
+      sha256: "8aab1771e1243a5063b8b0ff68042d67334e3feab9e95b9490f9a6ebf73b42ea"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.1.2"
+  characters:
+    dependency: transitive
+    description:
+      name: characters
+      sha256: faf38497bda5ead2a8c7615f4f7939df04333478bf32e4173fcb06d428b5716b
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.4.1"
+  clock:
+    dependency: transitive
+    description:
+      name: clock
+      sha256: fddb70d9b5277016c77a80201021d40a2247104d9f4aa7bab7157b7e3f05b84b
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.1.2"
+  code_assets:
+    dependency: transitive
+    description:
+      name: code_assets
+      sha256: "83ccdaa064c980b5596c35dd64a8d3ecc68620174ab9b90b6343b753aa721687"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.0.0"
+  collection:
+    dependency: transitive
+    description:
+      name: collection
+      sha256: "2f5709ae4d3d59dd8f7cd309b4e023046b57d8a6c82130785d2b0e5868084e76"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.19.1"
+  cross_file:
+    dependency: transitive
+    description:
+      name: cross_file
+      sha256: "28bb3ae56f117b5aec029d702a90f57d285cd975c3c5c281eaca38dbc47c5937"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.3.5+2"
+  crypto:
+    dependency: transitive
+    description:
+      name: crypto
+      sha256: c8ea0233063ba03258fbcf2ca4d6dadfefe14f02fab57702265467a19f27fadf
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.0.7"
+  cupertino_icons:
+    dependency: "direct main"
+    description:
+      name: cupertino_icons
+      sha256: ba631d1c7f7bef6b729a622b7b752645a2d076dba9976925b8f25725a30e1ee6
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.0.8"
+  fake_async:
+    dependency: transitive
+    description:
+      name: fake_async
+      sha256: "5368f224a74523e8d2e7399ea1638b37aecfca824a3cc4dfdf77bf1fa905ac44"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.3.3"
+  ffi:
+    dependency: transitive
+    description:
+      name: ffi
+      sha256: "6d7fd89431262d8f3125e81b50d3847a091d846eafcd4fdb88dd06f36d705a45"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.2.0"
+  file:
+    dependency: transitive
+    description:
+      name: file
+      sha256: a3b4f84adafef897088c160faf7dfffb7696046cb13ae90b508c2cbc95d3b8d4
+      url: "https://pub.dev"
+    source: hosted
+    version: "7.0.1"
+  file_selector_linux:
+    dependency: transitive
+    description:
+      name: file_selector_linux
+      sha256: "2567f398e06ac72dcf2e98a0c95df2a9edd03c2c2e0cacd4780f20cdf56263a0"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.9.4"
+  file_selector_macos:
+    dependency: transitive
+    description:
+      name: file_selector_macos
+      sha256: "5e0bbe9c312416f1787a68259ea1505b52f258c587f12920422671807c4d618a"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.9.5"
+  file_selector_platform_interface:
+    dependency: transitive
+    description:
+      name: file_selector_platform_interface
+      sha256: "35e0bd61ebcdb91a3505813b055b09b79dfdc7d0aee9c09a7ba59ae4bb13dc85"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.7.0"
+  file_selector_windows:
+    dependency: transitive
+    description:
+      name: file_selector_windows
+      sha256: "62197474ae75893a62df75939c777763d39c2bc5f73ce5b88497208bc269abfd"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.9.3+5"
+  flutter:
+    dependency: "direct main"
+    description: flutter
+    source: sdk
+    version: "0.0.0"
+  flutter_colorpicker:
+    dependency: "direct main"
+    description:
+      name: flutter_colorpicker
+      sha256: "969de5f6f9e2a570ac660fb7b501551451ea2a1ab9e2097e89475f60e07816ea"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.1.0"
+  flutter_lints:
+    dependency: "direct dev"
+    description:
+      name: flutter_lints
+      sha256: "3f41d009ba7172d5ff9be5f6e6e6abb4300e263aab8866d2a0842ed2a70f8f0c"
+      url: "https://pub.dev"
+    source: hosted
+    version: "4.0.0"
+  flutter_plugin_android_lifecycle:
+    dependency: transitive
+    description:
+      name: flutter_plugin_android_lifecycle
+      sha256: ee8068e0e1cd16c4a82714119918efdeed33b3ba7772c54b5d094ab53f9b7fd1
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.0.33"
+  flutter_test:
+    dependency: "direct dev"
+    description: flutter
+    source: sdk
+    version: "0.0.0"
+  flutter_web_plugins:
+    dependency: transitive
+    description: flutter
+    source: sdk
+    version: "0.0.0"
+  glob:
+    dependency: transitive
+    description:
+      name: glob
+      sha256: c3f1ee72c96f8f78935e18aa8cecced9ab132419e8625dc187e1c2408efc20de
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.1.3"
+  hooks:
+    dependency: transitive
+    description:
+      name: hooks
+      sha256: "7a08a0d684cb3b8fb604b78455d5d352f502b68079f7b80b831c62220ab0a4f6"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.0.1"
+  http:
+    dependency: transitive
+    description:
+      name: http
+      sha256: "87721a4a50b19c7f1d49001e51409bddc46303966ce89a65af4f4e6004896412"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.6.0"
+  http_parser:
+    dependency: transitive
+    description:
+      name: http_parser
+      sha256: "178d74305e7866013777bab2c3d8726205dc5a4dd935297175b19a23a2e66571"
+      url: "https://pub.dev"
+    source: hosted
+    version: "4.1.2"
+  image:
+    dependency: "direct main"
+    description:
+      name: image
+      sha256: f9881ff4998044947ec38d098bc7c8316ae1186fa786eddffdb867b9bc94dfce
+      url: "https://pub.dev"
+    source: hosted
+    version: "4.8.0"
+  image_picker:
+    dependency: "direct main"
+    description:
+      name: image_picker
+      sha256: "784210112be18ea55f69d7076e2c656a4e24949fa9e76429fe53af0c0f4fa320"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.2.1"
+  image_picker_android:
+    dependency: transitive
+    description:
+      name: image_picker_android
+      sha256: eda9b91b7e266d9041084a42d605a74937d996b87083395c5e47835916a86156
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.8.13+14"
+  image_picker_for_web:
+    dependency: transitive
+    description:
+      name: image_picker_for_web
+      sha256: "66257a3191ab360d23a55c8241c91a6e329d31e94efa7be9cf7a212e65850214"
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.1.1"
+  image_picker_ios:
+    dependency: transitive
+    description:
+      name: image_picker_ios
+      sha256: b9c4a438a9ff4f60808c9cf0039b93a42bb6c2211ef6ebb647394b2b3fa84588
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.8.13+6"
+  image_picker_linux:
+    dependency: transitive
+    description:
+      name: image_picker_linux
+      sha256: "1f81c5f2046b9ab724f85523e4af65be1d47b038160a8c8deed909762c308ed4"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.2.2"
+  image_picker_macos:
+    dependency: transitive
+    description:
+      name: image_picker_macos
+      sha256: "86f0f15a309de7e1a552c12df9ce5b59fe927e71385329355aec4776c6a8ec91"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.2.2+1"
+  image_picker_platform_interface:
+    dependency: transitive
+    description:
+      name: image_picker_platform_interface
+      sha256: "567e056716333a1647c64bb6bd873cff7622233a5c3f694be28a583d4715690c"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.11.1"
+  image_picker_windows:
+    dependency: transitive
+    description:
+      name: image_picker_windows
+      sha256: d248c86554a72b5495a31c56f060cf73a41c7ff541689327b1a7dbccc33adfae
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.2.2"
+  leak_tracker:
+    dependency: transitive
+    description:
+      name: leak_tracker
+      sha256: "33e2e26bdd85a0112ec15400c8cbffea70d0f9c3407491f672a2fad47915e2de"
+      url: "https://pub.dev"
+    source: hosted
+    version: "11.0.2"
+  leak_tracker_flutter_testing:
+    dependency: transitive
+    description:
+      name: leak_tracker_flutter_testing
+      sha256: "1dbc140bb5a23c75ea9c4811222756104fbcd1a27173f0c34ca01e16bea473c1"
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.0.10"
+  leak_tracker_testing:
+    dependency: transitive
+    description:
+      name: leak_tracker_testing
+      sha256: "8d5a2d49f4a66b49744b23b018848400d23e54caf9463f4eb20df3eb8acb2eb1"
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.0.2"
+  lints:
+    dependency: transitive
+    description:
+      name: lints
+      sha256: "976c774dd944a42e83e2467f4cc670daef7eed6295b10b36ae8c85bcbf828235"
+      url: "https://pub.dev"
+    source: hosted
+    version: "4.0.0"
+  logging:
+    dependency: transitive
+    description:
+      name: logging
+      sha256: c8245ada5f1717ed44271ed1c26b8ce85ca3228fd2ffdb75468ab01979309d61
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.3.0"
+  matcher:
+    dependency: transitive
+    description:
+      name: matcher
+      sha256: "12956d0ad8390bbcc63ca2e1469c0619946ccb52809807067a7020d57e647aa6"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.12.18"
+  material_color_utilities:
+    dependency: transitive
+    description:
+      name: material_color_utilities
+      sha256: "9c337007e82b1889149c82ed242ed1cb24a66044e30979c44912381e9be4c48b"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.13.0"
+  meta:
+    dependency: transitive
+    description:
+      name: meta
+      sha256: "23f08335362185a5ea2ad3a4e597f1375e78bce8a040df5c600c8d3552ef2394"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.17.0"
+  mime:
+    dependency: transitive
+    description:
+      name: mime
+      sha256: "41a20518f0cb1256669420fdba0cd90d21561e560ac240f26ef8322e45bb7ed6"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.0.0"
+  native_toolchain_c:
+    dependency: transitive
+    description:
+      name: native_toolchain_c
+      sha256: "89e83885ba09da5fdf2cdacc8002a712ca238c28b7f717910b34bcd27b0d03ac"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.17.4"
+  objective_c:
+    dependency: transitive
+    description:
+      name: objective_c
+      sha256: "100a1c87616ab6ed41ec263b083c0ef3261ee6cd1dc3b0f35f8ddfa4f996fe52"
+      url: "https://pub.dev"
+    source: hosted
+    version: "9.3.0"
+  path:
+    dependency: transitive
+    description:
+      name: path
+      sha256: "75cca69d1490965be98c73ceaea117e8a04dd21217b37b292c9ddbec0d955bc5"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.9.1"
+  path_provider:
+    dependency: "direct main"
+    description:
+      name: path_provider
+      sha256: "50c5dd5b6e1aaf6fb3a78b33f6aa3afca52bf903a8a5298f53101fdaee55bbcd"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.1.5"
+  path_provider_android:
+    dependency: transitive
+    description:
+      name: path_provider_android
+      sha256: f2c65e21139ce2c3dad46922be8272bb5963516045659e71bb16e151c93b580e
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.2.22"
+  path_provider_foundation:
+    dependency: transitive
+    description:
+      name: path_provider_foundation
+      sha256: "2a376b7d6392d80cd3705782d2caa734ca4727776db0b6ec36ef3f1855197699"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.6.0"
+  path_provider_linux:
+    dependency: transitive
+    description:
+      name: path_provider_linux
+      sha256: f7a1fe3a634fe7734c8d3f2766ad746ae2a2884abe22e241a8b301bf5cac3279
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.2.1"
+  path_provider_platform_interface:
+    dependency: transitive
+    description:
+      name: path_provider_platform_interface
+      sha256: "88f5779f72ba699763fa3a3b06aa4bf6de76c8e5de842cf6f29e2e06476c2334"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.1.2"
+  path_provider_windows:
+    dependency: transitive
+    description:
+      name: path_provider_windows
+      sha256: bd6f00dbd873bfb70d0761682da2b3a2c2fccc2b9e84c495821639601d81afe7
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.3.0"
+  petitparser:
+    dependency: transitive
+    description:
+      name: petitparser
+      sha256: "91bd59303e9f769f108f8df05e371341b15d59e995e6806aefab827b58336675"
+      url: "https://pub.dev"
+    source: hosted
+    version: "7.0.2"
+  platform:
+    dependency: transitive
+    description:
+      name: platform
+      sha256: "5d6b1b0036a5f331ebc77c850ebc8506cbc1e9416c27e59b439f917a902a4984"
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.1.6"
+  plugin_platform_interface:
+    dependency: transitive
+    description:
+      name: plugin_platform_interface
+      sha256: "4820fbfdb9478b1ebae27888254d445073732dae3d6ea81f0b7e06d5dedc3f02"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.1.8"
+  posix:
+    dependency: transitive
+    description:
+      name: posix
+      sha256: "6323a5b0fa688b6a010df4905a56b00181479e6d10534cecfecede2aa55add61"
+      url: "https://pub.dev"
+    source: hosted
+    version: "6.0.3"
+  pub_semver:
+    dependency: transitive
+    description:
+      name: pub_semver
+      sha256: "5bfcf68ca79ef689f8990d1160781b4bad40a3bd5e5218ad4076ddb7f4081585"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.2.0"
+  sky_engine:
+    dependency: transitive
+    description: flutter
+    source: sdk
+    version: "0.0.0"
+  source_span:
+    dependency: transitive
+    description:
+      name: source_span
+      sha256: "56a02f1f4cd1a2d96303c0144c93bd6d909eea6bee6bf5a0e0b685edbd4c47ab"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.10.2"
+  stack_trace:
+    dependency: transitive
+    description:
+      name: stack_trace
+      sha256: "8b27215b45d22309b5cddda1aa2b19bdfec9df0e765f2de506401c071d38d1b1"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.12.1"
+  stream_channel:
+    dependency: transitive
+    description:
+      name: stream_channel
+      sha256: "969e04c80b8bcdf826f8f16579c7b14d780458bd97f56d107d3950fdbeef059d"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.1.4"
+  string_scanner:
+    dependency: transitive
+    description:
+      name: string_scanner
+      sha256: "921cd31725b72fe181906c6a94d987c78e3b98c2e205b397ea399d4054872b43"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.4.1"
+  term_glyph:
+    dependency: transitive
+    description:
+      name: term_glyph
+      sha256: "7f554798625ea768a7518313e58f83891c7f5024f88e46e7182a4558850a4b8e"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.2.2"
+  test_api:
+    dependency: transitive
+    description:
+      name: test_api
+      sha256: "93167629bfc610f71560ab9312acdda4959de4df6fac7492c89ff0d3886f6636"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.7.9"
+  typed_data:
+    dependency: transitive
+    description:
+      name: typed_data
+      sha256: f9049c039ebfeb4cf7a7104a675823cd72dba8297f264b6637062516699fa006
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.4.0"
+  vector_math:
+    dependency: transitive
+    description:
+      name: vector_math
+      sha256: d530bd74fea330e6e364cda7a85019c434070188383e1cd8d9777ee586914c5b
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.2.0"
+  vm_service:
+    dependency: transitive
+    description:
+      name: vm_service
+      sha256: "45caa6c5917fa127b5dbcfbd1fa60b14e583afdc08bfc96dda38886ca252eb60"
+      url: "https://pub.dev"
+    source: hosted
+    version: "15.0.2"
+  web:
+    dependency: transitive
+    description:
+      name: web
+      sha256: "868d88a33d8a87b18ffc05f9f030ba328ffefba92d6c127917a2ba740f9cfe4a"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.1.1"
+  xdg_directories:
+    dependency: transitive
+    description:
+      name: xdg_directories
+      sha256: "7a3f37b05d989967cdddcbb571f1ea834867ae2faa29725fd085180e0883aa15"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.1.0"
+  xml:
+    dependency: transitive
+    description:
+      name: xml
+      sha256: "971043b3a0d3da28727e40ed3e0b5d18b742fa5a68665cca88e74b7876d5e025"
+      url: "https://pub.dev"
+    source: hosted
+    version: "6.6.1"
+  yaml:
+    dependency: transitive
+    description:
+      name: yaml
+      sha256: b9da305ac7c39faa3f030eccd175340f968459dae4af175130b3fc47e40d76ce
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.1.3"
+sdks:
+  dart: ">=3.10.3 <4.0.0"
+  flutter: ">=3.38.4"

pubspec.yaml

@@ -13,6 +13,7 @@ dependencies:
   image_picker: ^1.1.2
   image: ^4.2.0
   flutter_colorpicker: ^1.1.0
+  path_provider: ^2.1.5
 
 dev_dependencies:
   flutter_test:

test/project_codec_test.dart

@@ -0,0 +1,53 @@
+import 'dart:typed_data';
+
+import 'package:flutter_test/flutter_test.dart';
+import 'package:korken_mosaic/project_codec.dart';
+
+void main() {
+  test('MosaicProjectData json roundtrip keeps values including catalog snapshot', () {
+    final original = MosaicProjectData(
+      useCapSize: true,
+      gridWidth: '50',
+      gridHeight: '40',
+      capSize: '10',
+      fidelityStructure: 0.3,
+      ditheringStrength: 0.2,
+      edgeEmphasis: 0.4,
+      colorVariation: 0.5,
+      selectedPreset: 'realistisch',
+      sourceImageBytes: Uint8List.fromList([1, 2, 3]),
+      catalogSnapshot: const [
+        MosaicPaletteSnapshotEntry(name: 'White', colorValue: 0xFFF2F2F2),
+        MosaicPaletteSnapshotEntry(name: 'Blue', colorValue: 0xFF3F6FD8),
+      ],
+      savedAt: DateTime.parse('2026-01-01T12:00:00Z'),
+    );
+
+    final decoded = MosaicProjectData.fromJson(original.toJson());
+
+    expect(decoded.useCapSize, isTrue);
+    expect(decoded.gridWidth, '50');
+    expect(decoded.gridHeight, '40');
+    expect(decoded.capSize, '10');
+    expect(decoded.selectedPreset, 'realistisch');
+    expect(decoded.sourceImageBytes, isNotNull);
+    expect(decoded.sourceImageBytes!, [1, 2, 3]);
+    expect(decoded.catalogSnapshot.length, 2);
+    expect(decoded.catalogSnapshot.first.name, 'White');
+    expect(decoded.catalogSnapshot.last.colorValue, 0xFF3F6FD8);
+  });
+
+  test('MosaicProjectData defaults to empty snapshot when old project has none', () {
+    final decoded = MosaicProjectData.fromJson({
+      'useCapSize': false,
+      'gridWidth': '40',
+      'gridHeight': '30',
+      'capSize': '12',
+      'selectedPreset': 'ausgewogen',
+      'savedAt': '2026-01-01T12:00:00Z',
+    });
+
+    expect(decoded.catalogSnapshot, isEmpty);
+    expect(decoded.sourceImageBytes, isNull);
+  });
+}

test/widget_test.dart

@@ -0,0 +1,35 @@
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:korken_mosaic/main.dart';
+
+void main() {
+  testWidgets('stepper blocks forward navigation without image and shows hint',
+      (WidgetTester tester) async {
+    await tester.pumpWidget(const KorkenMosaicApp());
+
+    expect(find.text('1) Bild'), findsOneWidget);
+    expect(find.text('2) Größe'), findsOneWidget);
+    expect(find.text('3) Farben'), findsOneWidget);
+    expect(find.text('4) Ergebnis'), findsOneWidget);
+
+    await tester.tap(find.text('Weiter'));
+    await tester.pump();
+
+    // Stays on step 1 because no source image is available yet.
+    expect(find.text('Import target image'), findsOneWidget);
+    expect(find.text('Bitte zuerst ein Bild auswählen.'), findsOneWidget);
+  });
+
+  testWidgets('generate actions are disabled without image',
+      (WidgetTester tester) async {
+    await tester.pumpWidget(const KorkenMosaicApp());
+
+    final fab = tester.widget<FloatingActionButton>(
+      find.byType(FloatingActionButton),
+    );
+    expect(fab.onPressed, isNull);
+
+    // Result-step action is not reachable before image selection.
+    expect(find.byKey(const Key('generate-btn')), findsNothing);
+  });
+}