Frontend first draft

frontend/pshared/lib/service/files.dart

@@ -0,0 +1,38 @@
+import 'dart:math';
+
+import 'package:cached_network_image/cached_network_image.dart';
+
+import 'package:share_plus/share_plus.dart';
+
+import 'package:pshared/service/authorization/service.dart';
+import 'package:pshared/utils/image/conversion.dart';
+import 'package:pshared/utils/image/transformed.dart';
+
+
+String generateRandomLatinString(int length) {
+  const String chars = 'abcdefghijklmnopqrstuvwxyz';
+  final Random random = Random.secure();
+  return List.generate(length, (index) => chars[random.nextInt(chars.length)]).join();
+}
+
+class FilesService {
+  static Future<String> uploadImage(
+    String objectType,
+    String? id,
+    XFile imageFile, {
+    Future<TransformedImage> Function(XFile) fileReader = defaultTransformImage,
+  }) async {
+    final objRef = id ?? generateRandomLatinString(16);
+    final image = await fileReader(imageFile);
+    final res = await AuthorizationService.getFileUploadResponseAuth(
+      objectType, 
+      'image/$objRef',
+      '$objRef.${image.imageType.split('/').last}', 
+      'image', 
+      image.imageType, 
+      image.bytes
+    );
+    CachedNetworkImage.evictFromCache(res);
+    return res;
+  }
+}