Camera1 To Camerax

[versions]
camerax = "<minimum_version_needed>"

[libraries]
androidx-camera-core = { group = "androidx.camera", name = "camera-core", version.ref = "camerax" }
androidx-camera-camera2 = { group = "androidx.camera", name = "camera-camera2", version.ref = "camerax" }
androidx-camera-lifecycle = { group = "androidx.camera", name = "camera-lifecycle", version.ref = "camerax" }
androidx-camera-view = { group = "androidx.camera", name = "camera-view", version.ref = "camerax" }
androidx-camera-compose = { group = "androidx.camera", name = "camera-compose", version.ref = "camerax" }

implementation(libs.androidx.camera.core)
implementation(libs.androidx.camera.camera2)
implementation(libs.androidx.camera.lifecycle)
implementation(libs.androidx.camera.view)
implementation(libs.androidx.camera.compose)

implementation "androidx.camera:camera-core:<minimum_version_needed>"
implementation "androidx.camera:camera-camera2:<minimum_version_needed>"
implementation "androidx.camera:camera-lifecycle:<minimum_version_needed>"
implementation "androidx.camera:camera-view:<minimum_version_needed>"
implementation "androidx.camera:camera-compose:<minimum_version_needed>"

val context = LocalContext.current
val lifecycleOwner = LocalLifecycleOwner.current
LaunchedEffect(context, lifecycleOwner) {
  val cameraProviderFuture = ProcessCameraProvider.getInstance(context)
  cameraProviderFuture.addListener({
      val cameraProvider = cameraProviderFuture.get()

      val cameraSelector = CameraSelector.Builder()
        .requireLensFacing(CameraSelector.LENS_FACING_BACK)
        .build()

      val preview = Preview.Builder().build()
      val imageCapture = ImageCapture.Builder()
        .setCaptureMode(ImageCapture.CAPTURE_MODE_MINIMIZE_LATENCY)
        .build()

      cameraProvider.unbindAll() // Unbind before rebinding

      val camera = cameraProvider.bindToLifecycle(
        lifecycleOwner,
        cameraSelector,
        preview,
        imageCapture
      )
      val cameraControl = camera.cameraControl
    }, ContextCompat.getMainExecutor(context)
  )
}

preview.setSurfaceProvider(previewView.surfaceProvider)

val factory = previewView.meteringPointFactory
val point = factory.createPoint(x, y) // x, y from touch event
val action = FocusMeteringAction.Builder(point, FocusMeteringAction.FLAG_AF).build()
cameraControl?.startFocusAndMetering(action)

var surfaceRequest by remember { mutableStateOf<SurfaceRequest?>(null) }
val preview = remember {
  Preview.Builder().build().apply {
    setSurfaceProvider { request -> surfaceRequest = request }
  }
}

surfaceRequest?.let { request ->
  CameraXViewfinder(
    surfaceRequest = request,
    coordinateTransformer = coordinateTransformer,
    modifier = Modifier
  )
}

// Inside your tap gesture handler...
val surfaceCoords = with(coordinateTransformer) { offset.transform() }
val factory = SurfaceOrientedMeteringPointFactory(
  request.resolution.width.toFloat(),
  request.resolution.height.toFloat()
)
val point = factory.createPoint(surfaceCoords.x, surfaceCoords.y)
val action = FocusMeteringAction.Builder(point, FocusMeteringAction.FLAG_AF).build()
cameraControl?.startFocusAndMetering(action)

LaunchedEffect(configuration) {
  if (!view.isInEditMode) {
    val rotation = view.display?.rotation ?: Surface.ROTATION_0
    imageCapture.targetRotation = rotation
    preview.targetRotation = rotation
  }
}

imageCapture.takePicture(
  cameraExecutor,
  object : ImageCapture.OnImageCapturedCallback() {
    override fun onCaptureSuccess(image: ImageProxy) {
      val buffer = image.planes[0].buffer
      val bytes = ByteArray(buffer.remaining())
      buffer.get(bytes)
      val bitmap = BitmapFactory.decodeByteArray(bytes, 0, bytes.size)

      // Adjust rotation natively via ImageProxy
      val matrix = Matrix()
      matrix.postRotate(image.imageInfo.rotationDegrees.toFloat())
      if (lensFacing == CameraSelector.LENS_FACING_FRONT) {
        matrix.postScale(-1f, 1f) // Mirror for front camera
      }

      val rotatedBitmap = Bitmap.createBitmap(
        bitmap, 0, 0, bitmap.width, bitmap.height, matrix, true
      )

      // MUST close proxy
      image.close()
    }

    override fun onError(exception: ImageCaptureException) {
      Log.e("CameraX", "Capture failed: ${exception.message}", exception)
    }
  }
)

lensFacing = if (lensFacing == CameraSelector.LENS_FACING_BACK) {
  CameraSelector.LENS_FACING_FRONT
} else {
  CameraSelector.LENS_FACING_BACK
}