handle missing webcam dependency on windows showing error alert with link to resolve

src/main/java/com/sparrowwallet/sparrow/AppServices.java

@@ -9,6 +9,7 @@ import com.sparrowwallet.drongo.psbt.PSBT;
 import com.sparrowwallet.drongo.uri.BitcoinURI;
 import com.sparrowwallet.drongo.wallet.KeystoreSource;
 import com.sparrowwallet.drongo.wallet.Wallet;
+import com.sparrowwallet.sparrow.control.TextUtils;
 import com.sparrowwallet.sparrow.control.TrayManager;
 import com.sparrowwallet.sparrow.event.*;
 import com.sparrowwallet.sparrow.io.Config;
@@ -27,10 +28,7 @@ import javafx.fxml.FXMLLoader;
 import javafx.scene.Node;
 import javafx.scene.Parent;
 import javafx.scene.Scene;
-import javafx.scene.control.Alert;
+import javafx.scene.control.*;
-import javafx.scene.control.ButtonType;
-import javafx.scene.control.Dialog;
-import javafx.scene.control.DialogPane;
 import javafx.scene.image.Image;
 import javafx.scene.text.Font;
 import javafx.stage.Screen;
@@ -38,6 +36,7 @@ import javafx.stage.Stage;
 import javafx.stage.Window;
 import javafx.util.Duration;
 import org.berndpruenster.netlayer.tor.Tor;
+import org.controlsfx.control.HyperlinkLabel;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -49,6 +48,8 @@ import java.time.LocalDateTime;
 import java.time.ZoneId;
 import java.time.temporal.ChronoUnit;
 import java.util.*;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 import java.util.stream.Collectors;
 
 public class AppServices {
@@ -514,6 +515,23 @@ public class AppServices {
         alert.getDialogPane().getScene().getStylesheets().add(AppServices.class.getResource("general.css").toExternalForm());
         alert.setTitle(title);
         alert.setHeaderText(title);
+
+        Pattern linkPattern = Pattern.compile("\\[(http.+)]");
+        Matcher matcher = linkPattern.matcher(content);
+        if(matcher.find()) {
+            String link = matcher.group(1);
+            HyperlinkLabel hyperlinkLabel = new HyperlinkLabel(content);
+            hyperlinkLabel.setMaxWidth(Double.MAX_VALUE);
+            hyperlinkLabel.setMaxHeight(Double.MAX_VALUE);
+            hyperlinkLabel.getStyleClass().add("content");
+            Label label = new Label();
+            hyperlinkLabel.setPrefWidth(Math.max(360, TextUtils.computeTextWidth(label.getFont(), link, 0.0D) + 50));
+            hyperlinkLabel.setOnAction(event -> {
+                get().getApplication().getHostServices().showDocument(link);
+            });
+            alert.getDialogPane().setContent(hyperlinkLabel);
+        }
+
         moveToActiveWindowScreen(alert);
         return alert.showAndWait();
     }

src/main/java/com/sparrowwallet/sparrow/control/QRScanDialog.java

@@ -113,7 +113,19 @@ public class QRScanDialog extends Dialog<QRScanDialog.Result> {
 
         webcamService.resultProperty().addListener(new QRResultListener());
         webcamService.setOnFailed(failedEvent -> {
-            Platform.runLater(() -> setResult(new Result(failedEvent.getSource().getException())));
+            Throwable exception = failedEvent.getSource().getException();
+
+            Throwable nested = exception;
+            while(nested.getCause() != null) {
+                nested = nested.getCause();
+            }
+            if(org.controlsfx.tools.Platform.getCurrent() == org.controlsfx.tools.Platform.WINDOWS &&
+                    nested.getMessage().startsWith("Library 'OpenIMAJGrabber' was not loaded successfully from file")) {
+                exception = new WebcamDependencyException("Your system is missing a dependency required for the webcam. Follow the link below for more details.\n\n[https://sparrowwallet.com/docs/faq.html#your-system-is-missing-a-dependency-for-the-webcam]", exception);
+            }
+
+            final Throwable result = exception;
+            Platform.runLater(() -> setResult(new Result(result)));
         });
         webcamService.start();
         webcamResolutionProperty.addListener((observable, oldValue, newResolution) -> {
@@ -715,6 +727,24 @@ public class QRScanDialog extends Dialog<QRScanDialog.Result> {
         }
     }
 
+    public static class WebcamDependencyException extends ScanException {
+        public WebcamDependencyException() {
+            super();
+        }
+
+        public WebcamDependencyException(String message) {
+            super(message);
+        }
+
+        public WebcamDependencyException(Throwable cause) {
+            super(cause);
+        }
+
+        public WebcamDependencyException(String message, Throwable cause) {
+            super(message, cause);
+        }
+    }
+
     public static class ScanDelayCalculator implements WebcamUpdater.DelayCalculator {
         public long calculateDelay(long snapshotDuration, double deviceFps) {
             return Math.max(SCAN_PERIOD_MILLIS - snapshotDuration, 0L);

src/main/java/com/sparrowwallet/sparrow/control/TextAreaDialog.java

@@ -12,10 +12,14 @@ import javafx.scene.image.ImageView;
 import javafx.scene.layout.HBox;
 import javafx.scene.layout.Priority;
 import org.controlsfx.glyphfont.Glyph;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.util.Optional;
 
 public class TextAreaDialog extends Dialog<String> {
+    private static final Logger log = LoggerFactory.getLogger(TextAreaDialog.class);
+
     private final TextArea textArea;
     private final String defaultValue;
 
@@ -99,6 +103,7 @@ public class TextAreaDialog extends Dialog<String> {
                         } else if(result.outputDescriptor != null) {
                             textArea.setText(result.outputDescriptor.toString(true));
                         } else if(result.exception != null) {
+                            log.error("Error scanning QR", result.exception);
                             AppServices.showErrorDialog("Error scanning QR", result.exception.getMessage());
                         }
                     }

src/main/java/com/sparrowwallet/sparrow/wallet/PaymentController.java

@@ -30,13 +30,19 @@ import javafx.scene.control.*;
 import org.controlsfx.validation.ValidationResult;
 import org.controlsfx.validation.ValidationSupport;
 import org.controlsfx.validation.Validator;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.net.URL;
 import java.text.DecimalFormat;
 import java.text.DecimalFormatSymbols;
 import java.util.*;
 
+import static com.sparrowwallet.sparrow.AppServices.showErrorDialog;
+
 public class PaymentController extends WalletFormController implements Initializable {
+    private static final Logger log = LoggerFactory.getLogger(PaymentController.class);
+
     private SendController sendController;
 
     private ValidationSupport validationSupport;
@@ -327,6 +333,9 @@ public class PaymentController extends WalletFormController implements Initializ
             QRScanDialog.Result result = optionalResult.get();
             if(result.uri != null) {
                 updateFromURI(result.uri);
+            } else if(result.exception != null) {
+                log.error("Error scanning QR", result.exception);
+                showErrorDialog("Error scanning QR", result.exception.getMessage());
             }
         }
     }

src/main/java/com/sparrowwallet/sparrow/wallet/SettingsController.java

@@ -289,6 +289,7 @@ public class SettingsController extends WalletFormController implements Initiali
             } else if(result.payload != null && !result.payload.isEmpty()) {
                 setDescriptorText(result.payload);
             } else if(result.exception != null) {
+                log.error("Error scanning QR", result.exception);
                 AppServices.showErrorDialog("Error scanning QR", result.exception.getMessage());
             }
         }