TF-56 Implement local file picker

lib/features/upload/domain/state/local_file_picker_state.dart

@@ -0,0 +1,26 @@
+
+import 'package:core/core.dart';
+import 'package:model/model.dart';
+
+class LocalFilePickerSuccess extends UIState {
+  final FileInfo fileInfo;
+
+  LocalFilePickerSuccess(this.fileInfo);
+
+  @override
+  List<Object> get props => [fileInfo];
+}
+
+class LocalFilePickerFailure extends FeatureFailure {
+  final exception;
+
+  LocalFilePickerFailure(this.exception);
+
+  @override
+  List<Object> get props => [exception];
+}
+
+class LocalFilePickerCancel extends FeatureFailure {
+  @override
+  List<Object> get props => [];
+}

lib/features/upload/domain/usecases/local_file_picker_interactor.dart

@@ -0,0 +1,30 @@
+
+import 'package:core/core.dart';
+import 'package:dartz/dartz.dart';
+import 'package:file_picker/file_picker.dart';
+import 'package:model/model.dart';
+import 'package:tmail_ui_user/features/upload/domain/state/local_file_picker_state.dart';
+
+class LocalFilePickerInteractor {
+
+  LocalFilePickerInteractor();
+
+  Stream<Either<Failure, Success>> execute({FileType fileType = FileType.any}) async* {
+    try {
+      final filesResult = await FilePicker.platform.pickFiles(type: fileType);
+      if (filesResult != null && filesResult.files.isNotEmpty) {
+        final platformFile = filesResult.files.first;
+        final fileInfoResult = FileInfo(
+          platformFile.name,
+          platformFile.path ?? '',
+          platformFile.size,
+        );
+        yield Right<Failure, Success>(LocalFilePickerSuccess(fileInfoResult));
+      } else {
+        yield Left<Failure, Success>(LocalFilePickerCancel());
+      }
+    } catch (exception) {
+      yield Left<Failure, Success>(LocalFilePickerFailure(exception));
+    }
+  }
+}