feat: retain last finalized image. (#61)

Author: Dhruv1797

lib/provider/image_loader.dart

@@ -1,30 +1,68 @@
+import 'dart:io';
 import 'dart:typed_data';
 
 import 'package:flutter/material.dart';
 import 'package:image/image.dart' as img;
 import 'package:image_cropper/image_cropper.dart';
 import 'package:image_picker/image_picker.dart';
+import 'package:path_provider/path_provider.dart';
+import 'package:path/path.dart' as path;
 
 class ImageLoader extends ChangeNotifier {
   img.Image? image;
   final List<img.Image> processedImgs = List.empty(growable: true);
+  bool isLoading = false;
 
-  void pickImage({required int width, required int height}) async {
+  Future<bool> pickImage({required int width, required int height}) async {
     final ImagePicker picker = ImagePicker();
     final XFile? file = await picker.pickImage(source: ImageSource.gallery);
-    if (file == null) return;
+    if (file == null) return false;
 
     final croppedFile = await ImageCropper().cropImage(
       sourcePath: file.path,
-      aspectRatio:
-          CropAspectRatio(ratioX: width.toDouble(), ratioY: height.toDouble()),
+      aspectRatio: CropAspectRatio(
+        ratioX: width.toDouble(),
+        ratioY: height.toDouble(),
+      ),
     );
-    if (croppedFile == null) return;
+    if (croppedFile == null) return false;
 
     processedImgs.clear();
     image = await img.decodeImageFile(croppedFile.path);
 
     notifyListeners();
+    return true;
+  }
+
+  Future<void> saveFinalizedImageBytes(Uint8List bytes) async {
+    final dir = await getApplicationDocumentsDirectory();
+    final file = File(path.join(dir.path, 'last_finalized.png'));
+    await file.writeAsBytes(bytes);
+  }
+
+  Future<void> loadFinalizedImage({
+    required int width,
+    required int height,
+  }) async {
+    isLoading = true;
+    notifyListeners();
+
+    try {
+      final dir = await getApplicationDocumentsDirectory();
+      final file = File('${dir.path}/last_finalized.png');
+
+      if (await file.exists()) {
+        final bytes = await file.readAsBytes();
+        final decoded = img.decodeImage(bytes);
+        if (decoded != null) {
+          final resized = img.copyResize(decoded, width: width, height: height);
+          image = resized;
+        }
+      }
+    } finally {
+      isLoading = false;
+      notifyListeners();
+    }
   }
 
   Future<void> updateImage({

lib/view/image_editor.dart

@@ -28,6 +28,20 @@ class _ImageEditorState extends State<ImageEditor> {
   List<img.Image> _rawImages = [];
   List<Uint8List> _processedPngs = [];
 
+  @override
+  void initState() {
+    super.initState();
+    Future.microtask(() {
+      final imgLoader = context.read<ImageLoader>();
+      if (imgLoader.image == null) {
+        imgLoader.loadFinalizedImage(
+          width: widget.epd.width,
+          height: widget.epd.height,
+        );
+      }
+    });
+  }
+
   void _onFilterSelected(int index) {
     if (_selectedFilterIndex != index) {
       setState(() {
@@ -127,29 +141,36 @@ class _ImageEditorState extends State<ImageEditor> {
             ),
         ],
       ),
-      body: SafeArea(
-        child: Padding(
-          padding: const EdgeInsets.symmetric(horizontal: 8.0),
-          child: _processedPngs.isNotEmpty
-              ? ImageList(
-                  key: ValueKey(_processedSourceImage),
-                  processedPngs: _processedPngs,
-                  epd: widget.epd,
-                  selectedIndex: _selectedFilterIndex,
-                  flipHorizontal: flipHorizontal,
-                  flipVertical: flipVertical,
-                  onFilterSelected: _onFilterSelected,
-                  onFlipHorizontal: toggleFlipHorizontal,
-                  onFlipVertical: toggleFlipVertical,
-                )
-              : const Center(
-                  child: Text(
-                    "Import an image to begin",
-                    style: TextStyle(color: Colors.grey, fontSize: 16),
-                  ),
-                ),
-        ),
-      ),
+      body: imgLoader.isLoading
+          ? const Center(
+              child: Text('Loading...',
+                  style: TextStyle(
+                    color: colorBlack,
+                    fontSize: 14,
+                  )))
+          : SafeArea(
+              child: Padding(
+                padding: const EdgeInsets.symmetric(horizontal: 8.0),
+                child: _processedPngs.isNotEmpty
+                    ? ImageList(
+                        key: ValueKey(_processedSourceImage),
+                        processedPngs: _processedPngs,
+                        epd: widget.epd,
+                        selectedIndex: _selectedFilterIndex,
+                        flipHorizontal: flipHorizontal,
+                        flipVertical: flipVertical,
+                        onFilterSelected: _onFilterSelected,
+                        onFlipHorizontal: toggleFlipHorizontal,
+                        onFlipVertical: toggleFlipVertical,
+                      )
+                    : const Center(
+                        child: Text(
+                          "Import an image to begin",
+                          style: TextStyle(color: Colors.grey, fontSize: 16),
+                        ),
+                      ),
+              ),
+            ),
       bottomNavigationBar: BottomActionMenu(
         epd: widget.epd,
         imgLoader: imgLoader,
@@ -193,8 +214,14 @@ class BottomActionMenu extends StatelessWidget {
                 context: context,
                 icon: Icons.add_photo_alternate_outlined,
                 label: 'Import New',
-                onTap: () {
-                  imgLoader.pickImage(width: epd.width, height: epd.height);
+                onTap: () async {
+                  final success = await imgLoader.pickImage(
+                      width: epd.width, height: epd.height);
+                  if (success && imgLoader.image != null) {
+                    final bytes =
+                        Uint8List.fromList(img.encodePng(imgLoader.image!));
+                    await imgLoader.saveFinalizedImageBytes(bytes);
+                  }
                 },
               ),
               _buildActionButton(
@@ -210,11 +237,12 @@ class BottomActionMenu extends StatelessWidget {
                     ),
                   );
                   if (canvasBytes != null) {
-                    imgLoader.updateImage(
+                    await imgLoader.updateImage(
                       bytes: canvasBytes,
                       width: epd.width,
                       height: epd.height,
                     );
+                    await imgLoader.saveFinalizedImageBytes(canvasBytes);
                   }
                 },
               ),

pubspec.yaml

@@ -42,6 +42,7 @@ dependencies:
   intl: ^0.19.0
   path_provider: ^2.0.15
   get_it: ^8.0.3
+  path: ^1.9.1
 
 dev_dependencies:
   flutter_test: