Merge branch 'master' into pavel/web-format

# Conflicts:
#	lib/src/web/base.dart

@@ -77,33 +77,41 @@ class _BarcodeScannerWithControllerState
                   child: Row(
                     mainAxisAlignment: MainAxisAlignment.spaceEvenly,
                     children: [
-                      IconButton(
-                        color: Colors.white,
-                        icon: ValueListenableBuilder(
-                          valueListenable: controller.torchState,
-                          builder: (context, state, child) {
-                            if (state == null) {
-                              return const Icon(
-                                Icons.flash_off,
-                                color: Colors.grey,
-                              );
-                            }
-                            switch (state as TorchState) {
-                              case TorchState.off:
-                                return const Icon(
-                                  Icons.flash_off,
-                                  color: Colors.grey,
-                                );
-                              case TorchState.on:
-                                return const Icon(
-                                  Icons.flash_on,
-                                  color: Colors.yellow,
-                                );
-                            }
-                          },
-                        ),
-                        iconSize: 32.0,
-                        onPressed: () => controller.toggleTorch(),
+                      ValueListenableBuilder(
+                        valueListenable: controller.hasTorchState,
+                        builder: (context, state, child) {
+                          if (state != true) {
+                            return const SizedBox.shrink();
+                          }
+                          return IconButton(
+                            color: Colors.white,
+                            icon: ValueListenableBuilder(
+                              valueListenable: controller.torchState,
+                              builder: (context, state, child) {
+                                if (state == null) {
+                                  return const Icon(
+                                    Icons.flash_off,
+                                    color: Colors.grey,
+                                  );
+                                }
+                                switch (state as TorchState) {
+                                  case TorchState.off:
+                                    return const Icon(
+                                      Icons.flash_off,
+                                      color: Colors.grey,
+                                    );
+                                  case TorchState.on:
+                                    return const Icon(
+                                      Icons.flash_on,
+                                      color: Colors.yellow,
+                                    );
+                                }
+                              },
+                            ),
+                            iconSize: 32.0,
+                            onPressed: () => controller.toggleTorch(),
+                          );
+                        },
                       ),
                       IconButton(
                         color: Colors.white,

@@ -84,11 +84,12 @@ class MobileScannerWebPlugin {
 
     // Check if stream is running
     if (barCodeReader.isStarted) {
+      final hasTorch = await barCodeReader.hasTorch();
       return {
         'ViewID': viewID,
         'videoWidth': barCodeReader.videoWidth,
         'videoHeight': barCodeReader.videoHeight,
-        'torchable': barCodeReader.hasTorch,
+        'torchable': hasTorch,
       };
     }
     try {
@@ -124,12 +125,17 @@ class MobileScannerWebPlugin {
           });
         }
       });
+      final hasTorch = await barCodeReader.hasTorch();
+
+      if (hasTorch && arguments.containsKey('torch')) {
+        barCodeReader.toggleTorch(enabled: arguments['torch'] as bool);
+      }
 
       return {
         'ViewID': viewID,
         'videoWidth': barCodeReader.videoWidth,
         'videoHeight': barCodeReader.videoHeight,
-        'torchable': barCodeReader.hasTorch,
+        'torchable': hasTorch,
       };
     } catch (e) {
       throw PlatformException(code: 'MobileScannerWeb', message: '$e');

@@ -99,19 +99,21 @@ class MobileScannerController {
 
   bool isStarting = false;
 
-  bool? _hasTorch;
+  /// A notifier that provides availability of the Torch (Flash)
+  final ValueNotifier<bool?> hasTorchState = ValueNotifier(false);
 
   /// Returns whether the device has a torch.
   ///
   /// Throws an error if the controller is not initialized.
   bool get hasTorch {
-    if (_hasTorch == null) {
+    final hasTorch = hasTorchState.value;
+    if (hasTorch == null) {
       throw const MobileScannerException(
         errorCode: MobileScannerErrorCode.controllerUninitialized,
       );
     }
 
-    return _hasTorch!;
+    return hasTorch;
   }
 
   /// Set the starting arguments for the camera
@@ -210,8 +212,9 @@ class MobileScannerController {
       );
     }
 
-    _hasTorch = startResult['torchable'] as bool? ?? false;
-    if (_hasTorch! && torchEnabled) {
+    final hasTorch = startResult['torchable'] as bool? ?? false;
+    hasTorchState.value = hasTorch;
+    if (hasTorch && torchEnabled) {
       torchState.value = TorchState.on;
     }
 
@@ -223,7 +226,7 @@ class MobileScannerController {
               startResult['videoHeight'] as double? ?? 0,
             )
           : toSize(startResult['size'] as Map? ?? {}),
-      hasTorch: _hasTorch!,
+      hasTorch: hasTorch,
       textureId: kIsWeb ? null : startResult['textureId'] as int?,
       webId: kIsWeb ? startResult['ViewID'] as String? : null,
     );
@@ -244,7 +247,7 @@ class MobileScannerController {
   ///
   /// Throws if the controller was not initialized.
   Future<void> toggleTorch() async {
-    final hasTorch = _hasTorch;
+    final hasTorch = hasTorchState.value;
 
     if (hasTorch == null) {
       throw const MobileScannerException(

-import 'dart:html';
+import 'dart:html' as html;
 
 import 'package:flutter/material.dart';
 import 'package:js/js.dart';
+import 'package:js/js_util.dart';
 import 'package:mobile_scanner/src/enums/camera_facing.dart';
 import 'package:mobile_scanner/src/objects/barcode.dart';
 import 'package:mobile_scanner/src/web/media.dart';
@@ -9,7 +10,7 @@ import 'package:mobile_scanner/src/web/media.dart';
 abstract class WebBarcodeReaderBase {
   /// Timer used to capture frames to be analyzed
   Duration frameInterval = const Duration(milliseconds: 200);
-  final DivElement videoContainer;
+  final html.DivElement videoContainer;
 
   WebBarcodeReaderBase({
     required this.videoContainer,
@@ -37,24 +38,24 @@ abstract class WebBarcodeReaderBase {
   Future<void> toggleTorch({required bool enabled});
 
   /// Determine whether device has flash
-  bool get hasTorch;
+  Future<bool> hasTorch();
 }
 
 mixin InternalStreamCreation on WebBarcodeReaderBase {
   /// The video stream.
   /// Will be initialized later to see which camera needs to be used.
-  MediaStream? localMediaStream;
-  final VideoElement video = VideoElement();
+  html.MediaStream? localMediaStream;
+  final html.VideoElement video = html.VideoElement();
 
   @override
   int get videoWidth => video.videoWidth;
   @override
   int get videoHeight => video.videoHeight;
 
-  Future<MediaStream?> initMediaStream(CameraFacing cameraFacing) async {
+  Future<html.MediaStream?> initMediaStream(CameraFacing cameraFacing) async {
     // Check if browser supports multiple camera's and set if supported
     final Map? capabilities =
-        window.navigator.mediaDevices?.getSupportedConstraints();
+        html.window.navigator.mediaDevices?.getSupportedConstraints();
     final Map<String, dynamic> constraints;
     if (capabilities != null && capabilities['facingMode'] as bool) {
       constraints = {
@@ -67,15 +68,15 @@ mixin InternalStreamCreation on WebBarcodeReaderBase {
       constraints = {'video': true};
     }
     final stream =
-        await window.navigator.mediaDevices?.getUserMedia(constraints);
+        await html.window.navigator.mediaDevices?.getUserMedia(constraints);
     return stream;
   }
 
-  void prepareVideoElement(VideoElement videoSource);
+  void prepareVideoElement(html.VideoElement videoSource);
 
   Future<void> attachStreamToVideo(
-    MediaStream stream,
-    VideoElement videoSource,
+    html.MediaStream stream,
+    html.VideoElement videoSource,
   );
 
   @override
@@ -98,19 +99,34 @@ mixin InternalStreamCreation on WebBarcodeReaderBase {
 
 /// Mixin for libraries that don't have built-in torch support
 mixin InternalTorchDetection on InternalStreamCreation {
+  Future<List<String>> getSupportedTorchStates() async {
+    try {
+      final track = localMediaStream?.getVideoTracks();
+      if (track != null) {
+        final imageCapture = ImageCapture(track.first);
+        final photoCapabilities = await promiseToFuture<PhotoCapabilities>(
+          imageCapture.getPhotoCapabilities(),
+        );
+        final fillLightMode = photoCapabilities.fillLightMode;
+        if (fillLightMode != null) {
+          return fillLightMode;
+        }
+      }
+    } catch (e) {
+      // ImageCapture is not supported by some browsers:
+      // https://developer.mozilla.org/en-US/docs/Web/API/ImageCapture#browser_compatibility
+    }
+    return [];
+  }
+
   @override
-  bool get hasTorch {
-    // TODO: fix flash light. See https://github.com/dart-lang/sdk/issues/48533
-    // final track = _localStream?.getVideoTracks();
-    // if (track != null) {
-    //   final imageCapture = html.ImageCapture(track.first);
-    //   final photoCapabilities = await imageCapture.getPhotoCapabilities();
-    // }
-    return false;
+  Future<bool> hasTorch() async {
+    return (await getSupportedTorchStates()).isNotEmpty;
   }
 
   @override
   Future<void> toggleTorch({required bool enabled}) async {
+    final hasTorch = await this.hasTorch();
     if (hasTorch) {
       final track = localMediaStream?.getVideoTracks();
       await track?.first.applyConstraints({
@@ -122,6 +138,28 @@ mixin InternalTorchDetection on InternalStreamCreation {
   }
 }
 
+@JS('Promise')
+@staticInterop
+class Promise<T> {}
+
+@JS()
+@anonymous
+class PhotoCapabilities {
+  /// Returns an array of available fill light options. Options include auto, off, or flash.
+  external List<String>? get fillLightMode;
+}
+
+@JS('ImageCapture')
+@staticInterop
+class ImageCapture {
+  /// MediaStreamTrack
+  external factory ImageCapture(dynamic track);
+}
+
+extension ImageCaptureExt on ImageCapture {
+  external Promise<PhotoCapabilities> getPhotoCapabilities();
+}
+
 @JS('Map')
 @staticInterop
 class JsMap {

@@ -7,10 +7,6 @@ import 'package:mobile_scanner/src/enums/camera_facing.dart';
 import 'package:mobile_scanner/src/objects/barcode.dart';
 import 'package:mobile_scanner/src/web/base.dart';
 
-@JS('Promise')
-@staticInterop
-class Promise<T> {}
-
 @JS('ZXing.BrowserMultiFormatReader')
 @staticInterop
 class JsZXingBrowserMultiFormatReader {