let torch state notify that it is unsupported

@@ -43,7 +43,9 @@ abstract class BarcodeReader {
 
   /// Check whether the active camera has a flashlight.
   Future<bool> hasTorch() {
-    throw UnimplementedError('hasTorch() has not been implemented.');
+    // The torch of a media stream is not available for video tracks.
+    // See https://developer.mozilla.org/en-US/docs/Web/API/MediaTrackConstraints#instance_properties_of_video_tracks
+    return Future<bool>.value(false);
   }
 
   /// Load the barcode reader library.
@@ -108,7 +110,10 @@ abstract class BarcodeReader {
 
   /// Set the torch state for the active camera to the given [value].
   Future<void> setTorchState(TorchState value) {
-    throw UnimplementedError('setTorchState() has not been implemented.');
+    throw UnsupportedError(
+      'Setting the torch state is not supported for video tracks on the web.\n'
+      'See https://developer.mozilla.org/en-US/docs/Web/API/MediaTrackConstraints#instance_properties_of_video_tracks',
+    );
   }
 
   /// Start the barcode reader and initialize the [videoStream].

@@ -77,7 +77,7 @@ class MobileScannerWeb extends MobileScannerPlatform {
 
   @override
   Stream<TorchState> get torchStateStream =>
-      _settingsController.stream.map((_) => TorchState.off);
+      _settingsController.stream.map((_) => TorchState.unavailable);
 
   @override
   Stream<double> get zoomScaleStateStream =>

@@ -3,7 +3,6 @@ import 'dart:js_interop';
 import 'dart:ui';
 
 import 'package:mobile_scanner/src/enums/barcode_format.dart';
-import 'package:mobile_scanner/src/enums/torch_state.dart';
 import 'package:mobile_scanner/src/objects/barcode_capture.dart';
 import 'package:mobile_scanner/src/objects/start_options.dart';
 import 'package:mobile_scanner/src/web/barcode_reader.dart';
@@ -165,17 +164,6 @@ final class ZXingBarcodeReader extends BarcodeReader {
   }
 
   @override
-  Future<bool> hasTorch() {
-    final web.MediaStream? mediaStream = _reader?.stream;
-
-    if (mediaStream == null) {
-      return Future<bool>.value(false);
-    }
-
-    return _mediaTrackConstraintsDelegate.hasFlashlight(mediaStream);
-  }
-
-  @override
   void setMediaTrackSettingsListener(
     void Function(web.MediaTrackSettings) listener,
   ) {
@@ -183,33 +171,6 @@ final class ZXingBarcodeReader extends BarcodeReader {
   }
 
   @override
-  Future<void> setTorchState(TorchState value) async {
-    switch (value) {
-      case TorchState.unavailable:
-        return Future<void>.value();
-      case TorchState.off:
-      case TorchState.on:
-        final web.MediaStream? mediaStream = _reader?.stream;
-
-        if (mediaStream == null) {
-          return Future<void>.value();
-        }
-
-        await _mediaTrackConstraintsDelegate.setFlashlightState(
-          mediaStream,
-          value,
-        );
-
-        final web.MediaTrackSettings? settings =
-            _mediaTrackConstraintsDelegate.getSettings(mediaStream);
-
-        if (settings != null) {
-          _onMediaTrackSettingsChanged?.call(settings);
-        }
-    }
-  }
-
-  @override
   Future<void> start(
     StartOptions options, {
     required web.HTMLVideoElement videoElement,