From 74c298fd933a296d5251fa96d9bf9d1ed45e3c57 Mon Sep 17 00:00:00 2001
From: Craig Raw <craigraw@gmail.com>
Date: Thu, 29 May 2025 13:58:46 +0200
Subject: [PATCH] iterate and remove faulty capture devices on opening qr scan
 dialog

---
 .../sparrow/control/QRScanDialog.java         | 15 ++++----
 .../sparrow/control/WebcamService.java        | 34 ++++++++++++++-----
 2 files changed, 32 insertions(+), 17 deletions(-)

diff --git a/src/main/java/com/sparrowwallet/sparrow/control/QRScanDialog.java b/src/main/java/com/sparrowwallet/sparrow/control/QRScanDialog.java
index d6c39809..608468c7 100644
--- a/src/main/java/com/sparrowwallet/sparrow/control/QRScanDialog.java
+++ b/src/main/java/com/sparrowwallet/sparrow/control/QRScanDialog.java
@@ -122,19 +122,21 @@ public class QRScanDialog extends Dialog<QRScanDialog.Result> {
             if(percentComplete.get() <= 0.0) {
                 Platform.runLater(() -> percentComplete.set(opening ? 0.0 : -1.0));
             }
+        });
 
-            if(opening) {
+        webcamService.openedProperty().addListener((_, _, opened) -> {
+            if(opened) {
                 Platform.runLater(() -> {
                     try {
                         postOpenUpdate = true;
-                        List<CaptureDevice> newDevices = new ArrayList<>(webcamService.getDevices());
+                        List<CaptureDevice> newDevices = new ArrayList<>(webcamService.getAvailableDevices());
                         newDevices.removeAll(foundDevices);
                         foundDevices.addAll(newDevices);
                         foundDevices.removeIf(device -> !webcamService.getDevices().contains(device));
 
-                        if(Config.get().getWebcamDevice() != null && webcamDeviceProperty.get() == null) {
+                        if(webcamService.getDevice() != null) {
                             for(CaptureDevice device : foundDevices) {
-                                if(device.getName().equals(Config.get().getWebcamDevice())) {
+                                if(device.equals(webcamService.getDevice())) {
                                     webcamDeviceProperty.set(device);
                                 }
                             }
@@ -146,10 +148,7 @@ public class QRScanDialog extends Dialog<QRScanDialog.Result> {
                         postOpenUpdate = false;
                     }
                 });
-            }
-        });
-        webcamService.closedProperty().addListener((_, _, closed) -> {
-           if(closed && webcamResolutionProperty.get() != null) {
+            } else if(webcamResolutionProperty.get() != null) {
                webcamService.setResolution(webcamResolutionProperty.get());
                webcamService.setDevice(webcamDeviceProperty.get());
                Platform.runLater(() -> {
diff --git a/src/main/java/com/sparrowwallet/sparrow/control/WebcamService.java b/src/main/java/com/sparrowwallet/sparrow/control/WebcamService.java
index e7f97973..bffa0532 100644
--- a/src/main/java/com/sparrowwallet/sparrow/control/WebcamService.java
+++ b/src/main/java/com/sparrowwallet/sparrow/control/WebcamService.java
@@ -35,12 +35,13 @@ public class WebcamService extends ScheduledService<Image> {
     private static final Logger log = LoggerFactory.getLogger(WebcamService.class);
 
     private List<CaptureDevice> devices;
+    private List<CaptureDevice> availableDevices;
     private Set<WebcamResolution> resolutions;
 
     private WebcamResolution resolution;
     private CaptureDevice device;
     private final BooleanProperty opening = new SimpleBooleanProperty(false);
-    private final BooleanProperty closed = new SimpleBooleanProperty(false);
+    private final BooleanProperty opened = new SimpleBooleanProperty(false);
 
     private final ObjectProperty<Result> resultProperty = new SimpleObjectProperty<>(null);
 
@@ -106,23 +107,26 @@ public class WebcamService extends ScheduledService<Image> {
             @Override
             protected Image call() throws Exception {
                 try {
-                    if(stream == null) {
+                    if(devices == null) {
                         devices = capture.getDevices();
+                        availableDevices = new ArrayList<>(devices);
 
                         if(devices.isEmpty()) {
                             throw new UnsupportedOperationException("No cameras available");
                         }
+                    }
 
-                        CaptureDevice selectedDevice = devices.stream().filter(d -> !d.getFormats().isEmpty()).findFirst().orElse(devices.getFirst());
+                    while(stream == null && !availableDevices.isEmpty()) {
+                        CaptureDevice selectedDevice = availableDevices.stream().filter(d -> !d.getFormats().isEmpty()).findFirst().orElse(availableDevices.getFirst());
 
                         if(device != null) {
-                            for(CaptureDevice webcam : devices) {
+                            for(CaptureDevice webcam : availableDevices) {
                                 if(webcam.getName().equals(device.getName())) {
                                     selectedDevice = webcam;
                                 }
                             }
                         } else if(Config.get().getWebcamDevice() != null) {
-                            for(CaptureDevice webcam : devices) {
+                            for(CaptureDevice webcam : availableDevices) {
                                 if(webcam.getName().equals(Config.get().getWebcamDevice())) {
                                     selectedDevice = webcam;
                                 }
@@ -170,15 +174,23 @@ public class WebcamService extends ScheduledService<Image> {
                         opening.set(true);
                         stream = device.openStream(format);
                         opening.set(false);
-                        closed.set(false);
 
                         try {
                             zoomLimits = stream.getPropertyLimits(CaptureProperty.Zoom);
                         } catch(Throwable e) {
                             log.debug("Error getting zoom limits on " + device + ", assuming no zoom function");
                         }
+
+                        if(stream == null) {
+                            availableDevices.remove(device);
+                        }
                     }
 
+                    if(stream == null) {
+                        throw new UnsupportedOperationException("No usable cameras available, tried " + devices);
+                    }
+
+                    opened.set(true);
                     BufferedImage originalImage = stream.capture();
                     CroppedDimension cropped = getCroppedDimension(originalImage);
                     BufferedImage croppedImage = originalImage.getSubimage(cropped.x, cropped.y, cropped.length, cropped.length);
@@ -211,7 +223,7 @@ public class WebcamService extends ScheduledService<Image> {
     public boolean cancel() {
         if(stream != null) {
             stream.close();
-            closed.set(true);
+            opened.set(false);
         }
 
         return super.cancel();
@@ -336,6 +348,10 @@ public class WebcamService extends ScheduledService<Image> {
         return devices;
     }
 
+    public List<CaptureDevice> getAvailableDevices() {
+        return availableDevices;
+    }
+
     public Set<WebcamResolution> getResolutions() {
         return resolutions;
     }
@@ -376,8 +392,8 @@ public class WebcamService extends ScheduledService<Image> {
         return opening;
     }
 
-    public BooleanProperty closedProperty() {
-        return closed;
+    public BooleanProperty openedProperty() {
+        return opened;
     }
 
     public static <T extends Enum<T>> T getNearestEnum(T target) {