feat: add barcode scanner plugin (#536)

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

@@ -0,0 +1,81 @@
+// Copyright 2019-2023 Tauri Programme within The Commons Conservancy
+// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: MIT
+
+import AVFoundation
+
+func createCaptureDeviceInput(
+  cameraDirection: String, backCamera: AVCaptureDevice?, frontCamera: AVCaptureDevice?
+) throws
+  -> AVCaptureDeviceInput
+{
+  var captureDevice: AVCaptureDevice
+  if cameraDirection == "back" {
+    if backCamera != nil {
+      captureDevice = backCamera!
+    } else {
+      throw CaptureError.backCameraUnavailable
+    }
+  } else {
+    if frontCamera != nil {
+      captureDevice = frontCamera!
+    } else {
+      throw CaptureError.frontCameraUnavailable
+    }
+  }
+  let captureDeviceInput: AVCaptureDeviceInput
+  do {
+    captureDeviceInput = try AVCaptureDeviceInput(device: captureDevice)
+  } catch let error as NSError {
+    throw CaptureError.couldNotCaptureInput(error: error)
+  }
+  return captureDeviceInput
+}
+
+func discoverCaptureDevices() -> [AVCaptureDevice] {
+  if #available(iOS 13.0, *) {
+    return AVCaptureDevice.DiscoverySession(
+      deviceTypes: [
+        .builtInTripleCamera, .builtInDualCamera, .builtInTelephotoCamera,
+        .builtInTrueDepthCamera,
+        .builtInUltraWideCamera, .builtInDualWideCamera, .builtInWideAngleCamera,
+      ], mediaType: .video, position: .unspecified
+    ).devices
+  } else {
+    return AVCaptureDevice.DiscoverySession(
+      deviceTypes: [
+        .builtInDualCamera, .builtInWideAngleCamera, .builtInTelephotoCamera,
+        .builtInTrueDepthCamera,
+      ], mediaType: .video, position: .unspecified
+    ).devices
+  }
+}
+
+func formatStringFromMetadata(_ type: AVMetadataObject.ObjectType) -> String {
+  switch type {
+  case AVMetadataObject.ObjectType.upce:
+    return "UPC_E"
+  case AVMetadataObject.ObjectType.ean8:
+    return "EAN_8"
+  case AVMetadataObject.ObjectType.ean13:
+    return "EAN_13"
+  case AVMetadataObject.ObjectType.code39:
+    return "CODE_39"
+  case AVMetadataObject.ObjectType.code93:
+    return "CODE_93"
+  case AVMetadataObject.ObjectType.code128:
+    return "CODE_128"
+  case AVMetadataObject.ObjectType.interleaved2of5:
+    return "ITF"
+  case AVMetadataObject.ObjectType.aztec:
+    return "AZTEC"
+  case AVMetadataObject.ObjectType.dataMatrix:
+    return "DATA_MATRIX"
+  case AVMetadataObject.ObjectType.pdf417:
+    return "PDF_417"
+  case AVMetadataObject.ObjectType.qr:
+    return "QR_CODE"
+  default:
+    return type.rawValue
+  }
+}