Integrate backup file validation to backup playground.

app/src/main/java/org/thoughtcrime/securesms/components/settings/app/internal/backup/InternalBackupPlaygroundFragment.kt

@@ -48,6 +48,7 @@ class InternalBackupPlaygroundFragment : ComposeFragment() {
   private val viewModel: InternalBackupPlaygroundViewModel by viewModels()
   private lateinit var exportFileLauncher: ActivityResultLauncher<Intent>
   private lateinit var importFileLauncher: ActivityResultLauncher<Intent>
+  private lateinit var validateFileLauncher: ActivityResultLauncher<Intent>
 
   override fun onCreate(savedInstanceState: Bundle?) {
     super.onCreate(savedInstanceState)
@@ -72,6 +73,16 @@ class InternalBackupPlaygroundFragment : ComposeFragment() {
         } ?: Toast.makeText(requireContext(), "No URI selected", Toast.LENGTH_SHORT).show()
       }
     }
+
+    validateFileLauncher = registerForActivityResult(ActivityResultContracts.StartActivityForResult()) { result ->
+      if (result.resultCode == RESULT_OK) {
+        result.data?.data?.let { uri ->
+          requireContext().contentResolver.getLength(uri)?.let { length ->
+            viewModel.validate(length) { requireContext().contentResolver.openInputStream(uri)!! }
+          }
+        } ?: Toast.makeText(requireContext(), "No URI selected", Toast.LENGTH_SHORT).show()
+      }
+    }
   }
 
   @Composable
@@ -103,7 +114,16 @@ class InternalBackupPlaygroundFragment : ComposeFragment() {
         exportFileLauncher.launch(intent)
       },
       onUploadToRemoteClicked = { viewModel.uploadBackupToRemote() },
-      onCheckRemoteBackupStateClicked = { viewModel.checkRemoteBackupState() }
+      onCheckRemoteBackupStateClicked = { viewModel.checkRemoteBackupState() },
+      onValidateFileClicked = {
+        val intent = Intent().apply {
+          action = Intent.ACTION_GET_CONTENT
+          type = "application/octet-stream"
+          addCategory(Intent.CATEGORY_OPENABLE)
+        }
+
+        validateFileLauncher.launch(intent)
+      }
     )
   }
 
@@ -120,6 +140,7 @@ fun Screen(
   onImportFileClicked: () -> Unit = {},
   onPlaintextClicked: () -> Unit = {},
   onSaveToDiskClicked: () -> Unit = {},
+  onValidateFileClicked: () -> Unit = {},
   onUploadToRemoteClicked: () -> Unit = {},
   onCheckRemoteBackupStateClicked: () -> Unit = {}
 ) {
@@ -165,6 +186,12 @@ fun Screen(
         Text("Import from file")
       }
 
+      Buttons.LargeTonal(
+        onClick = onValidateFileClicked
+      ) {
+        Text("Validate file")
+      }
+
       Spacer(modifier = Modifier.height(16.dp))
 
       when (state.backupState) {

app/src/main/java/org/thoughtcrime/securesms/components/settings/app/internal/backup/InternalBackupPlaygroundViewModel.kt

@@ -78,6 +78,19 @@ class InternalBackupPlaygroundViewModel : ViewModel() {
       }
   }
 
+  fun validate(length: Long, inputStreamFactory: () -> InputStream) {
+    val self = Recipient.self()
+    val selfData = BackupRepository.SelfData(self.aci.get(), self.pni.get(), self.e164.get(), ProfileKey(self.profileKey))
+
+    disposables += Single.fromCallable { BackupRepository.validate(length, inputStreamFactory, selfData) }
+      .subscribeOn(Schedulers.io())
+      .observeOn(AndroidSchedulers.mainThread())
+      .subscribe { nothing ->
+        backupData = null
+        _state.value = _state.value.copy(backupState = BackupState.NONE)
+      }
+  }
+
   fun onPlaintextToggled() {
     _state.value = _state.value.copy(plaintext = !_state.value.plaintext)
   }