Add message clear option

test/utils/image_message_parser_test.dart

@@ -0,0 +1,116 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:meshcore_sar_app/utils/image_message_parser.dart';
+
+void main() {
+  group('ImageEnvelope', () {
+    test('encodes and parses IE2 with compressed session id', () {
+      final env = ImageEnvelope(
+        sessionId: '0000000a',
+        format: ImageFormat.avif,
+        total: 14,
+        width: 256,
+        height: 171,
+        sizeBytes: 2100,
+        senderKey6: 'aabbccddeeff',
+        timestampSec: 1700000000,
+      );
+
+      final text = env.encode();
+      expect(text.startsWith('IE2:'), isTrue);
+      expect(text.split(':')[1], equals('a'));
+
+      final parsed = ImageEnvelope.tryParse(text);
+      expect(parsed, isNotNull);
+      expect(parsed!.sessionId, equals('0000000a'));
+      expect(parsed.format, equals(ImageFormat.avif));
+      expect(parsed.total, equals(14));
+      expect(parsed.width, equals(256));
+      expect(parsed.height, equals(171));
+      expect(parsed.sizeBytes, equals(2100));
+      expect(parsed.senderKey6, equals('aabbccddeeff'));
+      expect(parsed.version, equals(2));
+    });
+
+    test('rejects IE1 legacy prefix', () {
+      const legacy = 'IE1:deadbeef:0:7:128:128:1050:aabbccddeeff:1700000000:1';
+      expect(ImageEnvelope.tryParse(legacy), isNull);
+    });
+  });
+
+  group('ImageFetchRequest', () {
+    test('encodes and parses IR2 with compressed sid', () {
+      final req = ImageFetchRequest(
+        sessionId: '0000000a',
+        requesterKey6: 'ffeeddccbbaa',
+        timestampSec: 1700000001,
+      );
+
+      final text = req.encode();
+      expect(text.startsWith('IR2:'), isTrue);
+      expect(text.split(':')[1], equals('a'));
+
+      final parsed = ImageFetchRequest.tryParse(text);
+      expect(parsed, isNotNull);
+      expect(parsed!.sessionId, equals('0000000a'));
+      expect(parsed.want, equals('all'));
+      expect(parsed.requesterKey6, equals('ffeeddccbbaa'));
+      expect(parsed.version, equals(2));
+    });
+
+    test('encodes and parses compact missing index ranges', () {
+      final req = ImageFetchRequest(
+        sessionId: '0000000a',
+        want: 'missing',
+        missingIndices: const [0, 1, 2, 5, 6, 8],
+        requesterKey6: 'ffeeddccbbaa',
+        timestampSec: 1700000001,
+      );
+
+      final text = req.encode();
+      expect(text, contains(':m0-2.5-6.8:'));
+
+      final parsed = ImageFetchRequest.tryParse(text);
+      expect(parsed, isNotNull);
+      expect(parsed!.want, equals('missing'));
+      expect(parsed.missingIndices, equals([0, 1, 2, 5, 6, 8]));
+    });
+
+    test('rejects IR1 legacy prefix', () {
+      const legacy = 'IR1:00112233:a:ffeeddccbbaa:1700000001:1';
+      expect(ImageFetchRequest.tryParse(legacy), isNull);
+    });
+
+    test('encodes and parses binary fetch request', () {
+      final req = ImageFetchRequest(
+        sessionId: '01020304',
+        want: 'missing',
+        missingIndices: const [0, 2, 5],
+        requesterKey6: 'ffeeddccbbaa',
+        timestampSec: 1700000001,
+      );
+
+      final payload = req.encodeBinary();
+      expect(ImageFetchRequest.isRequestBinary(payload), isTrue);
+
+      final parsed = ImageFetchRequest.tryParseBinary(payload);
+      expect(parsed, isNotNull);
+      expect(parsed!.sessionId, equals('01020304'));
+      expect(parsed.want, equals('missing'));
+      expect(parsed.missingIndices, equals([0, 2, 5]));
+      expect(parsed.requesterKey6, equals('ffeeddccbbaa'));
+      expect(parsed.version, equals(2));
+    });
+  });
+
+  group('ImageFragmentAck', () {
+    test('encodes and parses binary ack', () {
+      final ack = ImageFragmentAck(sessionId: '01020304', index: 9);
+      final payload = ack.encodeBinary();
+      expect(ImageFragmentAck.isImageFragmentAckBinary(payload), isTrue);
+      final parsed = ImageFragmentAck.tryParseBinary(payload);
+      expect(parsed, isNotNull);
+      expect(parsed!.sessionId, equals('01020304'));
+      expect(parsed.index, equals(9));
+    });
+  });
+}