add platform type to userAgent header

packages/stream_chat/lib/src/client.dart

@@ -10,6 +10,7 @@ import 'package:stream_chat/src/api/retry_policy.dart';
 import 'package:stream_chat/src/event_type.dart';
 import 'package:stream_chat/src/models/attachment_file.dart';
 import 'package:stream_chat/src/models/own_user.dart';
+import 'package:stream_chat/src/platform_detector/platform_detector.dart';
 import 'package:stream_chat/version.dart';
 import 'package:uuid/uuid.dart';
 
@@ -888,9 +889,8 @@ class StreamChatClient {
 
   String get _authType => _anonymous ? 'anonymous' : 'jwt';
 
-  // TODO: get the right version of the lib from the build toolchain
   String get _userAgent =>
-      'stream-chat-dart-client-${PACKAGE_VERSION.split('+')[0]}';
+      'stream-chat-dart-client-${Platform.name}-${PACKAGE_VERSION.split('+')[0]}';
 
   Map<String, String> get _commonQueryParams => {
         'user_id': state.user?.id,

packages/stream_chat/lib/src/platform_detector/platform_detector.dart

@@ -0,0 +1,44 @@
+import 'platform_detector_web.dart' if (dart.library.io) 'src/platform_io.dart';
+
+enum PlatformType {
+  Android,
+  Ios,
+  Web,
+  MacOS,
+  Windows,
+  Linux,
+  Fuchsia,
+}
+
+abstract class Platform {
+  static bool get isAndroid => currentPlatform == PlatformType.Android;
+  static bool get isIos => currentPlatform == PlatformType.Ios;
+  static bool get isWeb => currentPlatform == PlatformType.Web;
+  static bool get isMacOS => currentPlatform == PlatformType.MacOS;
+  static bool get isWindows => currentPlatform == PlatformType.Windows;
+  static bool get isLinux => currentPlatform == PlatformType.Linux;
+  static bool get isFuchsia => currentPlatform == PlatformType.Fuchsia;
+
+  static String get name {
+    switch (currentPlatform) {
+      case PlatformType.Android:
+        return 'android';
+      case PlatformType.Ios:
+        return 'ios';
+      case PlatformType.Web:
+        return 'web';
+      case PlatformType.MacOS:
+        return 'macos';
+      case PlatformType.Windows:
+        return 'windows';
+      case PlatformType.Linux:
+        return 'linux';
+      case PlatformType.Fuchsia:
+        return 'fuchsia';
+      default:
+        return '';
+    }
+  }
+
+  PlatformType get type => currentPlatform;
+}

packages/stream_chat/lib/src/platform_detector/platform_detector_io.dart

@@ -0,0 +1,11 @@
+import 'dart:io';
+import 'platform_detector.dart';
+
+PlatformType get currentPlatform {
+  if (Platform.isWindows) return PlatformType.Windows;
+  if (Platform.isFuchsia) return PlatformType.Fuchsia;
+  if (Platform.isMacOS) return PlatformType.MacOS;
+  if (Platform.isLinux) return PlatformType.Linux;
+  if (Platform.isIos) return PlatformType.Ios;
+  return PlatformType.Android;
+}

packages/stream_chat/lib/src/platform_detector/platform_detector_web.dart

@@ -0,0 +1,3 @@
+import 'platform_detector.dart';
+
+PlatformType get currentPlatform => PlatformType.Web;