Implement restoring of backup and show progress in UI

Note that the progress view is not exact as the progress reporting of
AOSP seems to be buggy.

app/src/main/java/com/stevesoltys/backup/Backup.kt

@@ -62,3 +62,5 @@ class Backup : Application() {
 }
 
 fun Uri.isOnExternalStorage() = authority == URI_AUTHORITY_EXTERNAL_STORAGE
+
+fun isDebugBuild() = Build.TYPE == "userdebug"

app/src/main/java/com/stevesoltys/backup/NotificationBackupObserver.kt

@@ -3,6 +3,7 @@ package com.stevesoltys.backup
 import android.app.backup.BackupProgress
 import android.app.backup.IBackupObserver
 import android.content.Context
+import android.content.pm.PackageManager
 import android.util.Log
 import android.util.Log.INFO
 import android.util.Log.isLoggable
@@ -62,10 +63,12 @@ class NotificationBackupObserver(context: Context, private val userInitiated: Bo
         nm.onBackupFinished()
     }
 
-    private fun getAppName(packageId: String): CharSequence {
+    private fun getAppName(packageId: String): CharSequence = getAppName(pm, packageId)
+
+}
+
+fun getAppName(pm: PackageManager, packageId: String): CharSequence {
     if (packageId == "@pm@") return packageId
     val appInfo = pm.getApplicationInfo(packageId, 0)
     return pm.getApplicationLabel(appInfo)
 }
-
-}

app/src/main/java/com/stevesoltys/backup/restore/RestoreActivity.kt

@@ -1,6 +1,7 @@
 package com.stevesoltys.backup.restore
 
 import android.os.Bundle
+import androidx.lifecycle.Observer
 import androidx.lifecycle.ViewModelProviders
 import com.stevesoltys.backup.R
 import com.stevesoltys.backup.ui.BackupActivity
@@ -20,7 +21,13 @@ class RestoreActivity : BackupActivity() {
 
         setContentView(R.layout.activity_fragment_container)
 
-        if (savedInstanceState == null) showFragment(getInitialFragment())
+        viewModel.chosenRestoreSet.observe(this, Observer { set ->
+            if (set != null) showFragment(RestoreProgressFragment())
+        })
+
+        if (savedInstanceState == null && viewModel.validLocationIsSet()) {
+            showFragment(getInitialFragment())
+        }
     }
 
     override fun onInvalidLocation() {

app/src/main/java/com/stevesoltys/backup/restore/RestoreProgressFragment.kt

@@ -0,0 +1,70 @@
+package com.stevesoltys.backup.restore
+
+import android.os.Bundle
+import android.view.LayoutInflater
+import android.view.View
+import android.view.View.INVISIBLE
+import android.view.View.VISIBLE
+import android.view.ViewGroup
+import android.view.WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON
+import androidx.fragment.app.Fragment
+import androidx.lifecycle.Observer
+import androidx.lifecycle.ViewModelProviders
+import com.stevesoltys.backup.R
+import com.stevesoltys.backup.getAppName
+import com.stevesoltys.backup.isDebugBuild
+import kotlinx.android.synthetic.main.fragment_restore_progress.*
+
+class RestoreProgressFragment : Fragment() {
+
+    private lateinit var viewModel: RestoreViewModel
+
+    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?,
+                              savedInstanceState: Bundle?): View? {
+        return inflater.inflate(R.layout.fragment_restore_progress, container, false)
+    }
+
+    override fun onActivityCreated(savedInstanceState: Bundle?) {
+        super.onActivityCreated(savedInstanceState)
+
+        // decryption will fail when the device is locked, so keep the screen on to prevent locking
+        requireActivity().window.addFlags(FLAG_KEEP_SCREEN_ON)
+
+        viewModel = ViewModelProviders.of(requireActivity()).get(RestoreViewModel::class.java)
+
+        viewModel.numPackages.observe(this, Observer { numPackages ->
+            progressBar.min = 0
+            progressBar.max = numPackages
+        })
+
+        viewModel.chosenRestoreSet.observe(this, Observer { set ->
+            backupNameView.text = set.device
+        })
+
+        viewModel.restoreProgress.observe(this, Observer { progress ->
+            progressBar.progress = progress.nowBeingRestored
+            val appName = getAppName(requireActivity().packageManager, progress.currentPackage)
+            val displayName = if (isDebugBuild()) "$appName (${progress.currentPackage})" else appName
+            currentPackageView.text = getString(R.string.restore_current_package, displayName)
+        })
+
+        viewModel.restoreFinished.observe(this, Observer { finished ->
+            progressBarIndefinite.visibility = INVISIBLE
+            progressBar.progress = viewModel.numPackages.value ?: progressBar.max
+            button.visibility = VISIBLE
+            if (finished == 0) {
+                // success
+                currentPackageView.text = getString(R.string.restore_finished_success)
+                warningView.visibility = VISIBLE
+            } else {
+                // error
+                currentPackageView.text = getString(R.string.restore_finished_error)
+                currentPackageView.setTextColor(warningView.textColors)
+            }
+            activity?.window?.clearFlags(FLAG_KEEP_SCREEN_ON)
+        })
+
+        button.setOnClickListener { requireActivity().finishAfterTransition() }
+    }
+
+}

app/src/main/java/com/stevesoltys/backup/restore/RestoreSetAdapter.kt

@@ -34,7 +34,7 @@ internal class RestoreSetAdapter(
         internal fun bind(item: RestoreSet) {
             v.setOnClickListener { listener.onRestoreSetClicked(item) }
             titleView.text = item.name
-            subtitleView.text = item.device
+            subtitleView.text = "Android Backup" // TODO change to backup date when available
         }
 
     }

app/src/main/java/com/stevesoltys/backup/restore/RestoreSetFragment.kt

@@ -2,7 +2,6 @@ package com.stevesoltys.backup.restore
 
 import android.app.backup.RestoreSet
 import android.os.Bundle
-import android.util.Log
 import android.view.LayoutInflater
 import android.view.View
 import android.view.View.INVISIBLE
@@ -14,7 +13,7 @@ import androidx.lifecycle.ViewModelProviders
 import com.stevesoltys.backup.R
 import kotlinx.android.synthetic.main.fragment_restore_set.*
 
-class RestoreSetFragment : Fragment(), RestoreSetClickListener {
+class RestoreSetFragment : Fragment() {
 
     private lateinit var viewModel: RestoreViewModel
 
@@ -34,8 +33,10 @@ class RestoreSetFragment : Fragment(), RestoreSetClickListener {
 
     override fun onStart() {
         super.onStart()
+        if (viewModel.recoveryCodeIsSet() && viewModel.validLocationIsSet()) {
             viewModel.loadRestoreSets()
         }
+    }
 
     private fun onRestoreSetsLoaded(result: RestoreSetResult) {
         if (result.hasError()) {
@@ -49,14 +50,10 @@ class RestoreSetFragment : Fragment(), RestoreSetClickListener {
             listView.visibility = VISIBLE
             progressBar.visibility = INVISIBLE
 
-            listView.adapter = RestoreSetAdapter(this, result.sets)
+            listView.adapter = RestoreSetAdapter(viewModel, result.sets)
         }
     }
 
-    override fun onRestoreSetClicked(set: RestoreSet) {
-        Log.e("TEST", "RESTORE SET CLICKED: ${set.name} ${set.device} ${set.token}")
-    }
-
 }
 
 internal interface RestoreSetClickListener {

app/src/main/java/com/stevesoltys/backup/restore/RestoreViewModel.kt

@@ -6,6 +6,7 @@ import android.app.backup.IRestoreSession
 import android.app.backup.RestoreSet
 import android.net.Uri
 import android.util.Log
+import androidx.annotation.WorkerThread
 import androidx.lifecycle.LiveData
 import androidx.lifecycle.MutableLiveData
 import com.stevesoltys.backup.Backup
@@ -16,7 +17,7 @@ import com.stevesoltys.backup.ui.BackupViewModel
 
 private val TAG = RestoreViewModel::class.java.simpleName
 
-class RestoreViewModel(app: Application) : BackupViewModel(app) {
+class RestoreViewModel(app: Application) : BackupViewModel(app), RestoreSetClickListener {
 
     private val backupManager = Backup.backupManager
 
@@ -27,8 +28,21 @@ class RestoreViewModel(app: Application) : BackupViewModel(app) {
     private val mRestoreSets = MutableLiveData<RestoreSetResult>()
     internal val restoreSets: LiveData<RestoreSetResult> get() = mRestoreSets
 
+    private val mChosenRestoreSet = MutableLiveData<RestoreSet>()
+    internal val chosenRestoreSet: LiveData<RestoreSet> get() = mChosenRestoreSet
+
+    private var mNumPackages = MutableLiveData<Int>()
+    internal val numPackages: LiveData<Int> get() = mNumPackages
+
+    private val mRestoreProgress = MutableLiveData<RestoreProgress>()
+    internal val restoreProgress: LiveData<RestoreProgress> get() = mRestoreProgress
+
+    private val mRestoreFinished = MutableLiveData<Int>()
+    // Zero on success; a nonzero error code if the restore operation as a whole failed.
+    internal val restoreFinished: LiveData<Int> get() = mRestoreFinished
+
     override fun acceptBackupLocation(folderUri: Uri): Boolean {
-        // TODO
+        // TODO search if there's really a backup available in this location and see if we can decrypt it
         return true
     }
 
@@ -52,6 +66,14 @@ class RestoreViewModel(app: Application) : BackupViewModel(app) {
         }
     }
 
+    override fun onRestoreSetClicked(set: RestoreSet) {
+        val session = this.session
+        check(session != null)
+        session.restoreAll(set.token, observer, monitor)
+
+        mChosenRestoreSet.value = set
+    }
+
     override fun onCleared() {
         super.onCleared()
         endSession()
@@ -63,8 +85,11 @@ class RestoreViewModel(app: Application) : BackupViewModel(app) {
         observer = null
     }
 
+    @WorkerThread
     private inner class RestoreObserver : IRestoreObserver.Stub() {
 
+        private var correctedNow: Int = -1
+
         /**
          * Supply a list of the restore datasets available from the current transport.
          * This method is invoked as a callback following the application's use of the
@@ -76,7 +101,7 @@ class RestoreViewModel(app: Application) : BackupViewModel(app) {
          */
         override fun restoreSetsAvailable(restoreSets: Array<out RestoreSet>?) {
             if (restoreSets == null || restoreSets.isEmpty()) {
-                mRestoreSets.value = RestoreSetResult(app.getString(R.string.restore_set_empty_result))
+                mRestoreSets.postValue(RestoreSetResult(app.getString(R.string.restore_set_empty_result)))
             } else {
                 mRestoreSets.postValue(RestoreSetResult(restoreSets))
             }
@@ -88,7 +113,7 @@ class RestoreViewModel(app: Application) : BackupViewModel(app) {
          * @param numPackages The total number of packages being processed in this restore operation.
          */
         override fun restoreStarting(numPackages: Int) {
-            Log.e(TAG, "RESTORE STARTING $numPackages")
+            mNumPackages.postValue(numPackages)
         }
 
         /**
@@ -101,17 +126,22 @@ class RestoreViewModel(app: Application) : BackupViewModel(app) {
          * @param currentPackage The name of the package now being restored.
          */
         override fun onUpdate(nowBeingRestored: Int, currentPackage: String) {
-            Log.e(TAG, "RESTORE UPDATE $nowBeingRestored $currentPackage")
+            if (nowBeingRestored <= correctedNow) {
+                correctedNow += 1
+            } else {
+                correctedNow = nowBeingRestored
+            }
+            mRestoreProgress.postValue(RestoreProgress(correctedNow, currentPackage))
         }
 
         /**
          * The restore operation has completed.
          *
-         * @param error Zero on success; a nonzero error code if the restore operation
+         * @param result Zero on success; a nonzero error code if the restore operation
          *   as a whole failed.
          */
-        override fun restoreFinished(error: Int) {
+        override fun restoreFinished(result: Int) {
-            Log.e(TAG, "RESTORE FINISHED $error")
+            mRestoreFinished.postValue(result)
             endSession()
         }
 
@@ -129,3 +159,7 @@ internal class RestoreSetResult(
 
     internal fun hasError(): Boolean = errorMsg != null
 }
+
+internal class RestoreProgress(
+        internal val nowBeingRestored: Int,
+        internal val currentPackage: String)

app/src/main/java/com/stevesoltys/backup/transport/restore/KVRestore.kt

@@ -13,6 +13,7 @@ import com.stevesoltys.backup.header.UnsupportedVersionException
 import libcore.io.IoUtils.closeQuietly
 import java.io.IOException
 import java.util.*
+import javax.crypto.AEADBadTagException
 
 private class KVRestoreState(
         internal val token: Long,
@@ -86,6 +87,9 @@ internal class KVRestore(
         } catch (e: UnsupportedVersionException) {
             Log.e(TAG, "Unsupported version in backup: ${e.version}", e)
             TRANSPORT_ERROR
+        } catch (e: AEADBadTagException) {
+            Log.e(TAG, "Decryption failed", e)
+            TRANSPORT_ERROR
         } finally {
             this.state = null
             closeQuietly(data)

app/src/main/java/com/stevesoltys/backup/ui/BackupActivity.kt

@@ -59,7 +59,9 @@ abstract class BackupActivity : AppCompatActivity() {
 
     @CallSuper
     override fun onActivityResult(requestCode: Int, resultCode: Int, result: Intent?) {
-        if (resultCode != RESULT_OK) {
+        if (resultCode == RESULT_OK && requestCode == REQUEST_CODE_OPEN_DOCUMENT_TREE) {
+            getViewModel().handleChooseFolderResult(result)
+        } else if (resultCode != RESULT_OK) {
             Log.w(TAG, "Error in activity result: $requestCode")
             finishAfterTransition()
         } else {

app/src/main/java/com/stevesoltys/backup/ui/BackupLocationFragment.kt

@@ -1,6 +1,5 @@
 package com.stevesoltys.backup.ui
 
-import android.app.Activity.RESULT_OK
 import android.content.ActivityNotFoundException
 import android.content.Intent
 import android.content.Intent.*
@@ -8,23 +7,17 @@ import android.os.Bundle
 import android.provider.DocumentsContract.EXTRA_PROMPT
 import android.widget.Toast
 import android.widget.Toast.LENGTH_LONG
-import androidx.lifecycle.ViewModelProviders
 import androidx.preference.Preference
 import androidx.preference.PreferenceFragmentCompat
 import com.stevesoltys.backup.R
-import com.stevesoltys.backup.settings.SettingsViewModel
 
 class BackupLocationFragment : PreferenceFragmentCompat() {
 
-    private lateinit var viewModel: SettingsViewModel
-
     override fun onCreatePreferences(savedInstanceState: Bundle?, rootKey: String?) {
         setPreferencesFromResource(R.xml.backup_location, rootKey)
 
         requireActivity().setTitle(R.string.settings_backup_location_title)
 
-        viewModel = ViewModelProviders.of(requireActivity()).get(SettingsViewModel::class.java)
-
         val externalStorage = Preference(requireContext()).apply {
             setIcon(R.drawable.ic_storage)
             setTitle(R.string.settings_backup_external_storage)
@@ -43,18 +36,11 @@ class BackupLocationFragment : PreferenceFragmentCompat() {
                 FLAG_GRANT_READ_URI_PERMISSION or FLAG_GRANT_WRITE_URI_PERMISSION)
         try {
             val documentChooser = createChooser(openTreeIntent, null)
-            startActivityForResult(documentChooser, REQUEST_CODE_OPEN_DOCUMENT_TREE)
+            // start from the activity context, so we can receive and handle the result there
+            requireActivity().startActivityForResult(documentChooser, REQUEST_CODE_OPEN_DOCUMENT_TREE)
         } catch (ex: ActivityNotFoundException) {
             Toast.makeText(requireContext(), "Please install a file manager.", LENGTH_LONG).show()
         }
     }
 
-    override fun onActivityResult(requestCode: Int, resultCode: Int, result: Intent?) {
-        if (resultCode == RESULT_OK && requestCode == REQUEST_CODE_OPEN_DOCUMENT_TREE) {
-            viewModel.handleChooseFolderResult(result)
-        } else {
-            super.onActivityResult(requestCode, resultCode, result)
-        }
-    }
-
 }

app/src/main/java/com/stevesoltys/backup/ui/BackupViewModel.kt

@@ -23,10 +23,10 @@ abstract class BackupViewModel(protected val app: Application) : AndroidViewMode
      * Will be set to true if this is the initial location.
      * It will be false if an existing location was changed.
      */
-    internal val onLocationSet: LiveEvent<LocationResult> = locationWasSet
+    internal val onLocationSet: LiveEvent<LocationResult> get() = locationWasSet
 
     private val mChooseBackupLocation = MutableLiveEvent<Boolean>()
-    internal val chooseBackupLocation: LiveEvent<Boolean> = mChooseBackupLocation
+    internal val chooseBackupLocation: LiveEvent<Boolean> get() = mChooseBackupLocation
     internal fun chooseBackupLocation() = mChooseBackupLocation.setEvent(true)
 
     internal fun recoveryCodeIsSet() = Backup.keyManager.hasBackupKey()
@@ -52,12 +52,12 @@ abstract class BackupViewModel(protected val app: Application) : AndroidViewMode
             // store backup folder location in settings
             setBackupFolderUri(app, folderUri)
 
-            // notify the UI that the location has been set
-            locationWasSet.setEvent(LocationResult(true, initialSetUp))
-
             // stop backup service to be sure the old location will get updated
             app.stopService(Intent(app, ConfigurableBackupTransportService::class.java))
 
+            // notify the UI that the location has been set
+            locationWasSet.setEvent(LocationResult(true, initialSetUp))
+
             Log.d(TAG, "New storage location chosen: $folderUri")
         } else {
             Log.w(TAG, "Location was rejected: $folderUri")

app/src/main/java/com/stevesoltys/backup/ui/RecoveryCodeInputFragment.kt

@@ -1,6 +1,5 @@
 package com.stevesoltys.backup.ui
 
-import android.os.Build
 import android.os.Bundle
 import android.view.LayoutInflater
 import android.view.View
@@ -11,6 +10,7 @@ import android.widget.Toast.LENGTH_LONG
 import androidx.fragment.app.Fragment
 import androidx.lifecycle.ViewModelProviders
 import com.stevesoltys.backup.R
+import com.stevesoltys.backup.isDebugBuild
 import io.github.novacrypto.bip39.Validation.InvalidChecksumException
 import io.github.novacrypto.bip39.Validation.WordNotFoundException
 import kotlinx.android.synthetic.main.fragment_recovery_code_input.*
@@ -37,7 +37,7 @@ class RecoveryCodeInputFragment : Fragment() {
         }
         doneButton.setOnClickListener { done() }
 
-        if (Build.TYPE == "userdebug") debugPreFill()
+        if (isDebugBuild()) debugPreFill()
     }
 
     private fun getInput(): List<CharSequence> = ArrayList<String>(WORD_NUM).apply {

app/src/main/res/layout/fragment_restore_progress.xml

@@ -0,0 +1,110 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent">
+
+    <ImageView
+        android:id="@+id/imageView"
+        android:layout_width="32dp"
+        android:layout_height="32dp"
+        android:layout_margin="16dp"
+        android:tint="?android:colorAccent"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toTopOf="parent"
+        app:srcCompat="@drawable/ic_cloud_download"
+        tools:ignore="ContentDescription" />
+
+    <TextView
+        android:id="@+id/titleView"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_margin="16dp"
+        android:text="@string/restore_restoring"
+        android:textColor="?android:textColorSecondary"
+        android:textSize="24sp"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toBottomOf="@+id/imageView" />
+
+    <TextView
+        android:id="@+id/backupNameView"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_margin="16dp"
+        android:textColor="?android:textColorTertiary"
+        android:textSize="18sp"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toBottomOf="@+id/titleView"
+        tools:text="Pixel 2 XL" />
+
+    <TextView
+        android:id="@+id/currentPackageView"
+        android:layout_width="0dp"
+        android:layout_height="wrap_content"
+        android:layout_marginStart="16dp"
+        android:layout_marginTop="32dp"
+        android:layout_marginEnd="16dp"
+        android:gravity="center_horizontal"
+        android:textColor="?android:textColorSecondary"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toBottomOf="@+id/backupNameView"
+        tools:text="@string/restore_current_package" />
+
+    <ProgressBar
+        android:id="@+id/progressBarIndefinite"
+        style="?android:attr/progressBarStyle"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_margin="16dp"
+        android:indeterminate="true"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toBottomOf="@+id/currentPackageView" />
+
+    <ProgressBar
+        android:id="@+id/progressBar"
+        style="?android:attr/progressBarStyleHorizontal"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_margin="16dp"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toBottomOf="@+id/progressBarIndefinite"
+        tools:progress="50" />
+
+    <TextView
+        android:id="@+id/warningView"
+        android:layout_width="0dp"
+        android:layout_height="wrap_content"
+        android:layout_marginStart="16dp"
+        android:layout_marginTop="32dp"
+        android:layout_marginEnd="16dp"
+        android:text="@string/restore_finished_warning_only_installed"
+        android:textColor="@android:color/holo_red_dark"
+        android:visibility="gone"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintTop_toBottomOf="@+id/progressBar"
+        tools:visibility="visible" />
+
+    <Button
+        android:id="@+id/button"
+        style="@style/Widget.AppCompat.Button.Colored"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginEnd="16dp"
+        android:layout_marginBottom="16dp"
+        android:text="@string/restore_finished_button"
+        android:visibility="invisible"
+        app:layout_constraintBottom_toBottomOf="parent"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintTop_toBottomOf="@+id/warningView"
+        app:layout_constraintVertical_bias="1.0"
+        tools:visibility="visible" />
+
+</androidx.constraintlayout.widget.ConstraintLayout>

app/src/main/res/values/strings.xml

@@ -77,5 +77,11 @@
     <string name="restore_back">Don\'t restore</string>
     <string name="restore_set_error">An error occurred loading the backups.</string>
     <string name="restore_set_empty_result">No backups found at given location.</string>
+    <string name="restore_restoring">Restoring Backup</string>
+    <string name="restore_current_package">Restoring %s…</string>
+    <string name="restore_finished_success">Restore complete.</string>
+    <string name="restore_finished_error">An error occurred while restoring the backup.</string>
+    <string name="restore_finished_warning_only_installed">Note that we could only restore data for apps that are already installed.\n\nWhen you install more apps, we will try to restore their data and settings from this backup. So please do not delete it as long as it might still be needed.</string>
+    <string name="restore_finished_button">Finish</string>
 
 </resources>