fix(barcode-scanner): check if iOS platform supports scanning (#3222)

.changes/fix-barcode-scanner-ios-sim-crash.md

@@ -0,0 +1,6 @@
+---
+barcode-scanner: patch
+barcode-scanner-js: patch
+---
+
+On iOS, fixed an application crash happening when the scanner was started on the iOS Simulator (no camera available).

plugins/barcode-scanner/ios/Sources/BarcodeScannerPlugin.swift

@@ -269,20 +269,20 @@ class BarcodeScannerPlugin: Plugin, AVCaptureMetadataOutputObjectsDelegate {
     scanFormats = [AVMetadataObject.ObjectType]()
 
     (args.formats ?? []).forEach { format in
-        if let formatValue = format.value {
-            scanFormats.append(formatValue)
-        } else {
-            invoke.reject("Unsupported barcode format on this iOS version: \(format)")
-            return
-        }
+      if let formatValue = format.value {
+        scanFormats.append(formatValue)
+      } else {
+        invoke.reject("Unsupported barcode format on this iOS version: \(format)")
+        return
+      }
     }
 
     if scanFormats.isEmpty {
-        for supportedFormat in SupportedFormat.allCases {
-            if let formatValue = supportedFormat.value {
-                scanFormats.append(formatValue)
-            }
+      for supportedFormat in SupportedFormat.allCases {
+        if let formatValue = supportedFormat.value {
+          scanFormats.append(formatValue)
         }
+      }
     }
 
     self.metaOutput!.metadataObjectTypes = self.scanFormats
@@ -305,6 +305,13 @@ class BarcodeScannerPlugin: Plugin, AVCaptureMetadataOutputObjectsDelegate {
       return
     }
 
+    // Check if camera is available on this platform (iOS simulator doesn't have cameras)
+    let availableVideoDevices = discoverCaptureDevices()
+    if availableVideoDevices.isEmpty {
+      invoke.reject("No camera available on this device (e.g., iOS Simulator)")
+      return
+    }
+
     var iOS14min: Bool = false
     if #available(iOS 14.0, *) { iOS14min = true }
     if !iOS14min && self.getPermissionState() != "granted" {