Merge branch 'master' into github-action-unit-tests

ground/src/main/java/com/google/android/ground/ui/datacollection/tasks/photo/PhotoTaskViewModel.kt

@@ -15,7 +15,11 @@
  */
 package com.google.android.ground.ui.datacollection.tasks.photo
 
+import android.content.Context
 import android.content.res.Resources
+import android.graphics.Bitmap
+import android.graphics.Matrix
+import android.media.ExifInterface
 import android.net.Uri
 import androidx.lifecycle.LiveData
 import androidx.lifecycle.asLiveData
@@ -25,14 +29,17 @@ import com.google.android.ground.persistence.remote.firebase.FirebaseStorageMana
 import com.google.android.ground.repository.UserMediaRepository
 import com.google.android.ground.ui.datacollection.tasks.AbstractTaskViewModel
 import com.google.android.ground.ui.util.BitmapUtil
+import dagger.hilt.android.qualifiers.ApplicationContext
 import java.io.IOException
+import java.lang.UnsupportedOperationException
 import javax.inject.Inject
 import kotlinx.coroutines.flow.map
 import timber.log.Timber
 
 class PhotoTaskViewModel
 @Inject
 constructor(
+  @ApplicationContext private val context: Context,
   private val userMediaRepository: UserMediaRepository,
   private val bitmapUtil: BitmapUtil,
   resources: Resources,
@@ -50,6 +57,15 @@ constructor(
     taskTaskData.map { userMediaRepository.getDownloadUrl(it?.getDetailsText()) }.asLiveData()
   val isPhotoPresent: LiveData<Boolean> = taskTaskData.map { it.isNotNullOrEmpty() }.asLiveData()
 
+  private fun rotateBitmap(bitmap: Bitmap, rotateDegrees: Float): Bitmap {
+    val matrix = Matrix()
+    // Rotate iff rotation is non-zero.
+    if (rotateDegrees != 0f) {
+      matrix.postRotate(rotateDegrees)
+    }
+    return Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(), matrix, true)
+  }
+
   /**
    * Saves photo data stored on an on-device URI in Ground-associated storage and prepares it for
    * inclusion in a data collection submission.
@@ -59,7 +75,9 @@ constructor(
     requireNotNull(currentTask) { "Photo captured but no task waiting for the result" }
 
     try {
-      val bitmap = bitmapUtil.fromUri(uri)
+      val orientation = getOrientationFromExif(uri)
+      val rotateDegrees = getRotationDegrees(orientation)
+      val bitmap = rotateBitmap(bitmapUtil.fromUri(uri), rotateDegrees)
       val file = userMediaRepository.savePhoto(bitmap, currentTask)
       userMediaRepository.addImageToGallery(file.absolutePath, file.name)
       val remoteFilename = FirebaseStorageManager.getRemoteMediaPath(surveyId, file.absolutePath)
@@ -68,4 +86,26 @@ constructor(
       Timber.e(e, "Error getting photo selected from storage")
     }
   }
+
+  /**
+   * Returns the number of degrees a photo should be rotated based on the value of its orientation
+   * EXIF tag.
+   */
+  private fun getRotationDegrees(orientation: Int): Float =
+    when (orientation) {
+      ExifInterface.ORIENTATION_NORMAL -> 0f
+      ExifInterface.ORIENTATION_ROTATE_90 -> 90f
+      ExifInterface.ORIENTATION_ROTATE_180 -> 180f
+      ExifInterface.ORIENTATION_ROTATE_270 -> 270f
+      else -> throw UnsupportedOperationException("Unsupported photo orientation $orientation")
+    }
+
+  /** Returns the EXIF orientation attribute of the JPEG image at the specified URI. */
+  private fun getOrientationFromExif(uri: Uri): Int {
+    val inputStream =
+      context.contentResolver.openInputStream(uri)
+        ?: throw IOException("Content resolver returned null for $uri")
+    val exif = ExifInterface(inputStream)
+    return exif.getAttributeInt(ExifInterface.TAG_ORIENTATION, ExifInterface.ORIENTATION_NORMAL)
+  }
 }