Save the time of the last backup and only do automatic flash drive backups once a day

This commit also turns SettingsManager into a class, so we can mock
and later also inject it.

app/src/androidTest/java/com/stevesoltys/backup/DocumentsStorageTest.kt

@@ -3,8 +3,6 @@ package com.stevesoltys.backup
 import androidx.documentfile.provider.DocumentFile
 import androidx.test.platform.app.InstrumentationRegistry
 import androidx.test.runner.AndroidJUnit4
-import com.stevesoltys.backup.settings.getBackupToken
-import com.stevesoltys.backup.settings.getStorage
 import com.stevesoltys.backup.transport.backup.plugins.DocumentsStorage
 import com.stevesoltys.backup.transport.backup.plugins.createOrGetFile
 import org.junit.After
@@ -21,9 +19,8 @@ private const val filename = "test-file"
 class DocumentsStorageTest {
 
     private val context = InstrumentationRegistry.getInstrumentation().targetContext
-    private val token = getBackupToken(context)
+    private val settingsManager = (context.applicationContext as Backup).settingsManager
-    private val folderUri = getStorage(context)
+    private val storage = DocumentsStorage(context, settingsManager)
-    private val storage = DocumentsStorage(context, folderUri, token)
 
     private lateinit var file: DocumentFile
 

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

@@ -3,12 +3,11 @@ package com.stevesoltys.backup
 import android.app.Application
 import android.app.backup.IBackupManager
 import android.content.Context.BACKUP_SERVICE
-import android.net.Uri
 import android.os.Build
 import android.os.ServiceManager.getService
 import com.stevesoltys.backup.crypto.KeyManager
 import com.stevesoltys.backup.crypto.KeyManagerImpl
-import com.stevesoltys.backup.ui.storage.AUTHORITY_STORAGE
+import com.stevesoltys.backup.settings.SettingsManager
 
 /**
  * @author Steve Soltys
@@ -25,6 +24,9 @@ class Backup : Application() {
         }
     }
 
+    val settingsManager by lazy {
+        SettingsManager(this)
+    }
     val notificationManager by lazy {
         BackupNotificationManager(this)
     }

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

@@ -13,9 +13,10 @@ import android.os.Handler
 import android.provider.DocumentsContract
 import android.util.Log
 import com.stevesoltys.backup.settings.FlashDrive
-import com.stevesoltys.backup.settings.getFlashDrive
 import com.stevesoltys.backup.transport.requestBackup
 import com.stevesoltys.backup.ui.storage.AUTHORITY_STORAGE
+import java.util.*
+import java.util.concurrent.TimeUnit.HOURS
 
 private val TAG = UsbIntentReceiver::class.java.simpleName
 
@@ -28,12 +29,17 @@ class UsbIntentReceiver : BroadcastReceiver() {
         Log.d(TAG, "New USB mass-storage device attached.")
         device.log()
 
-        val savedFlashDrive = getFlashDrive(context) ?: return
+        val settingsManager = (context.applicationContext as Backup).settingsManager
+        val savedFlashDrive = settingsManager.getFlashDrive() ?: return
         val attachedFlashDrive = FlashDrive.from(device)
         if (savedFlashDrive == attachedFlashDrive) {
-            Log.d(TAG, "Matches stored device, requesting backup...")
+            Log.d(TAG, "Matches stored device, checking backup time...")
-            // TODO only if last backup older than 24h
+            if (Date().time - settingsManager.getBackupTime() >= HOURS.toMillis(24)) {
+                Log.d(TAG, "Last backup older than 24 hours, requesting a backup...")
                 startBackupOnceMounted(context)
+            } else {
+                Log.d(TAG, "We have a recent backup, not requesting a new one.")
+            }
         }
     }
 

app/src/main/java/com/stevesoltys/backup/activity/MainActivityController.java

@@ -18,8 +18,6 @@ import static android.content.Intent.FLAG_GRANT_READ_URI_PERMISSION;
 import static android.content.Intent.FLAG_GRANT_WRITE_URI_PERMISSION;
 import static com.stevesoltys.backup.activity.MainActivity.OPEN_DOCUMENT_TREE_BACKUP_REQUEST_CODE;
 import static com.stevesoltys.backup.activity.MainActivity.OPEN_DOCUMENT_TREE_REQUEST_CODE;
-import static com.stevesoltys.backup.settings.SettingsManagerKt.getBackupPassword;
-import static com.stevesoltys.backup.settings.SettingsManagerKt.getStorage;
 
 /**
  * @author Steve Soltys
@@ -41,7 +39,7 @@ public class MainActivityController {
     }
 
     boolean isChangeBackupLocationButtonVisible(Activity parent) {
-        return getStorage(parent) != null;
+        return false;
     }
 
     private void showChooseFolderActivity(Activity parent, boolean continueToBackup) {
@@ -74,17 +72,10 @@ public class MainActivityController {
     }
 
     boolean onAutomaticBackupsButtonClicked(Activity parent) {
-        if (getStorage(parent) == null || getBackupPassword(parent) == null) {
         Toast.makeText(parent, "Please make at least one manual backup first.", Toast.LENGTH_SHORT).show();
         return false;
     }
 
-        // show Toast informing the user
-        Toast.makeText(parent, "REMOVED", Toast.LENGTH_SHORT).show();
-
-        return true;
-    }
-
     void onChangeBackupLocationButtonClicked(Activity parent) {
         showChooseFolderActivity(parent, false);
     }

app/src/main/java/com/stevesoltys/backup/activity/backup/CreateBackupActivityController.java

@@ -21,8 +21,6 @@ import com.stevesoltys.backup.service.backup.BackupService;
 import java.util.Set;
 import java.util.concurrent.atomic.AtomicReference;
 
-import static com.stevesoltys.backup.settings.SettingsManagerKt.getBackupPassword;
-
 /**
  * @author Steve Soltys
  */
@@ -70,13 +68,8 @@ class CreateBackupActivityController {
     }
 
     void onCreateBackupButtonClicked(Set<String> selectedPackages, Activity parent) {
-        String password = getBackupPassword(parent);
-        if (password == null) {
-            showEnterPasswordAlert(selectedPackages, parent);
-        } else {
         backupService.backupPackageData(selectedPackages, parent);
     }
-    }
 
     private void showEnterPasswordAlert(Set<String> selectedPackages, Activity parent) {
         final EditText passwordTextView = new EditText(parent);

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

@@ -10,10 +10,10 @@ 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.Backup
 import com.stevesoltys.backup.R
 import com.stevesoltys.backup.getAppName
 import com.stevesoltys.backup.isDebugBuild
-import com.stevesoltys.backup.settings.getStorage
 import kotlinx.android.synthetic.main.fragment_restore_progress.*
 
 class RestoreProgressFragment : Fragment() {
@@ -49,7 +49,8 @@ class RestoreProgressFragment : Fragment() {
             if (finished == 0) {
                 // success
                 currentPackageView.text = getString(R.string.restore_finished_success)
-                warningView.text = if (getStorage(requireContext())?.ejectable == true) {
+                val settingsManager = (requireContext().applicationContext as Backup).settingsManager
+                warningView.text = if (settingsManager.getStorage()?.ejectable == true) {
                     getString(R.string.restore_finished_warning_only_installed, getString(R.string.restore_finished_warning_ejectable))
                 } else {
                     getString(R.string.restore_finished_warning_only_installed, null)

app/src/main/java/com/stevesoltys/backup/settings/SettingsFragment.kt

@@ -6,6 +6,8 @@ import android.os.Bundle
 import android.os.RemoteException
 import android.provider.Settings
 import android.provider.Settings.Secure.BACKUP_AUTO_RESTORE
+import android.text.format.DateUtils
+import android.text.format.DateUtils.*
 import android.util.Log
 import android.view.Menu
 import android.view.MenuInflater
@@ -18,6 +20,7 @@ import androidx.preference.TwoStatePreference
 import com.stevesoltys.backup.Backup
 import com.stevesoltys.backup.R
 import com.stevesoltys.backup.restore.RestoreActivity
+import java.util.*
 
 private val TAG = SettingsFragment::class.java.name
 
@@ -26,6 +29,7 @@ class SettingsFragment : PreferenceFragmentCompat() {
     private val backupManager = Backup.backupManager
 
     private lateinit var viewModel: SettingsViewModel
+    private lateinit var settingsManager: SettingsManager
 
     private lateinit var backup: TwoStatePreference
     private lateinit var autoRestore: TwoStatePreference
@@ -36,6 +40,7 @@ class SettingsFragment : PreferenceFragmentCompat() {
         setHasOptionsMenu(true)
 
         viewModel = ViewModelProviders.of(requireActivity()).get(SettingsViewModel::class.java)
+        settingsManager = (requireContext().applicationContext as Backup).settingsManager
 
         backup = findPreference<TwoStatePreference>("backup")!!
         backup.onPreferenceChangeListener = OnPreferenceChangeListener { _, newValue ->
@@ -74,7 +79,8 @@ class SettingsFragment : PreferenceFragmentCompat() {
         super.onStart()
 
         // we need to re-set the title when returning to this fragment
-        requireActivity().setTitle(R.string.app_name)
+        val activity = requireActivity()
+        activity.setTitle(R.string.app_name)
 
         try {
             backup.isChecked = backupManager.isBackupEnabled
@@ -84,12 +90,21 @@ class SettingsFragment : PreferenceFragmentCompat() {
             backup.isEnabled = false
         }
 
-        val resolver = requireContext().contentResolver
+        val resolver = activity.contentResolver
         autoRestore.isChecked = Settings.Secure.getInt(resolver, BACKUP_AUTO_RESTORE, 1) == 1
 
-        // TODO add time of last backup here
+        // get name of storage location
-        val storageName = getStorage(requireContext())?.name
+        val storageName = settingsManager.getStorage()?.name
-        backupLocation.summary = storageName ?: getString(R.string.settings_backup_location_none )
+                ?: getString(R.string.settings_backup_location_none)
+
+        // get time of last backup
+        val lastBackupInMillis = settingsManager.getBackupTime()
+        val lastBackup = if (lastBackupInMillis == 0L) {
+            getString(R.string.settings_backup_last_backup_never)
+        } else {
+            getRelativeTimeSpanString(lastBackupInMillis, Date().time, MINUTE_IN_MILLIS, 0)
+        }
+        backupLocation.summary = getString(R.string.settings_backup_location_summary, storageName, lastBackup)
     }
 
     override fun onCreateOptionsMenu(menu: Menu, inflater: MenuInflater) {

app/src/main/java/com/stevesoltys/backup/settings/SettingsManager.kt

@@ -17,8 +17,104 @@ private const val PREF_KEY_FLASH_DRIVE_VENDOR_ID = "flashDriveVendorId"
 private const val PREF_KEY_FLASH_DRIVE_PRODUCT_ID = "flashDriveProductId"
 
 private const val PREF_KEY_BACKUP_TOKEN = "backupToken"
+private const val PREF_KEY_BACKUP_TIME = "backupTime"
 private const val PREF_KEY_BACKUP_PASSWORD = "backupLegacyPassword"
 
+class SettingsManager(context: Context) {
+
+    private val prefs = PreferenceManager.getDefaultSharedPreferences(context)
+
+    fun setStorage(storage: Storage) {
+        prefs.edit()
+                .putString(PREF_KEY_STORAGE_URI, storage.uri.toString())
+                .putString(PREF_KEY_STORAGE_NAME, storage.name)
+                .putBoolean(PREF_KEY_STORAGE_EJECTABLE, storage.ejectable)
+                .apply()
+    }
+
+    fun getStorage(): Storage? {
+        val uriStr = prefs.getString(PREF_KEY_STORAGE_URI, null) ?: return null
+        val uri = Uri.parse(uriStr)
+        val name = prefs.getString(PREF_KEY_STORAGE_NAME, null) ?: throw IllegalStateException()
+        val ejectable = prefs.getBoolean(PREF_KEY_STORAGE_EJECTABLE, false)
+        return Storage(uri, name, ejectable)
+    }
+
+    fun setFlashDrive(usb: FlashDrive?) {
+        if (usb == null) {
+            prefs.edit()
+                    .remove(PREF_KEY_FLASH_DRIVE_NAME)
+                    .remove(PREF_KEY_FLASH_DRIVE_SERIAL_NUMBER)
+                    .remove(PREF_KEY_FLASH_DRIVE_VENDOR_ID)
+                    .remove(PREF_KEY_FLASH_DRIVE_PRODUCT_ID)
+                    .apply()
+        } else {
+            prefs.edit()
+                    .putString(PREF_KEY_FLASH_DRIVE_NAME, usb.name)
+                    .putString(PREF_KEY_FLASH_DRIVE_SERIAL_NUMBER, usb.serialNumber)
+                    .putInt(PREF_KEY_FLASH_DRIVE_VENDOR_ID, usb.vendorId)
+                    .putInt(PREF_KEY_FLASH_DRIVE_PRODUCT_ID, usb.productId)
+                    .apply()
+        }
+    }
+
+    fun getFlashDrive(): FlashDrive? {
+        val name = prefs.getString(PREF_KEY_FLASH_DRIVE_NAME, null) ?: return null
+        val serialNumber = prefs.getString(PREF_KEY_FLASH_DRIVE_SERIAL_NUMBER, null)
+        val vendorId = prefs.getInt(PREF_KEY_FLASH_DRIVE_VENDOR_ID, -1)
+        val productId = prefs.getInt(PREF_KEY_FLASH_DRIVE_PRODUCT_ID, -1)
+        return FlashDrive(name, serialNumber, vendorId, productId)
+    }
+
+    /**
+     * Generates and returns a new backup token while saving it as well.
+     * Subsequent calls to [getBackupToken] will return this new token once saved.
+     */
+    fun getAndSaveNewBackupToken(): Long = Date().time.apply {
+        prefs.edit()
+                .putLong(PREF_KEY_BACKUP_TOKEN, this)
+                .apply()
+    }
+
+    /**
+     * Returns the current backup token or 0 if none exists.
+     */
+    fun getBackupToken(): Long {
+        return prefs.getLong(PREF_KEY_BACKUP_TOKEN, 0L)
+    }
+
+    /**
+     * Sets the last backup time to "now".
+     */
+    fun saveNewBackupTime() {
+        prefs.edit()
+                .putLong(PREF_KEY_BACKUP_TIME, Date().time)
+                .apply()
+    }
+
+    /**
+     * Sets the last backup time to "never".
+     */
+    fun resetBackupTime() {
+        prefs.edit()
+                .putLong(PREF_KEY_BACKUP_TIME, 0L)
+                .apply()
+    }
+
+    /**
+     * Returns the last backup time in unix epoch milli seconds.
+     */
+    fun getBackupTime(): Long {
+        return prefs.getLong(PREF_KEY_BACKUP_TIME, 0L)
+    }
+
+    @Deprecated("Replaced by KeyManager#getBackupKey()")
+    fun getBackupPassword(): String? {
+        return prefs.getString(PREF_KEY_BACKUP_PASSWORD, null)
+    }
+
+}
+
 data class Storage(
         val uri: Uri,
         val name: String,
@@ -27,24 +123,6 @@ data class Storage(
             ?: throw AssertionError("Should only happen on API < 21.")
 }
 
-fun setStorage(context: Context, storage: Storage) {
-    PreferenceManager.getDefaultSharedPreferences(context)
-            .edit()
-            .putString(PREF_KEY_STORAGE_URI, storage.uri.toString())
-            .putString(PREF_KEY_STORAGE_NAME, storage.name)
-            .putBoolean(PREF_KEY_STORAGE_EJECTABLE, storage.ejectable)
-            .apply()
-}
-
-fun getStorage(context: Context): Storage? {
-    val prefs = PreferenceManager.getDefaultSharedPreferences(context)
-    val uriStr = prefs.getString(PREF_KEY_STORAGE_URI, null) ?: return null
-    val uri = Uri.parse(uriStr)
-    val name = prefs.getString(PREF_KEY_STORAGE_NAME, null) ?: throw IllegalStateException()
-    val ejectable = prefs.getBoolean(PREF_KEY_STORAGE_EJECTABLE, false)
-    return Storage(uri, name, ejectable)
-}
-
 data class FlashDrive(
         val name: String,
         val serialNumber: String?,
@@ -59,55 +137,3 @@ data class FlashDrive(
         )
     }
 }
-
-fun setFlashDrive(context: Context, usb: FlashDrive?) {
-    val prefs = PreferenceManager.getDefaultSharedPreferences(context)
-    if (usb == null) {
-        prefs.edit()
-                .remove(PREF_KEY_FLASH_DRIVE_NAME)
-                .remove(PREF_KEY_FLASH_DRIVE_SERIAL_NUMBER)
-                .remove(PREF_KEY_FLASH_DRIVE_VENDOR_ID)
-                .remove(PREF_KEY_FLASH_DRIVE_PRODUCT_ID)
-                .apply()
-    } else {
-        prefs.edit()
-                .putString(PREF_KEY_FLASH_DRIVE_NAME, usb.name)
-                .putString(PREF_KEY_FLASH_DRIVE_SERIAL_NUMBER, usb.serialNumber)
-                .putInt(PREF_KEY_FLASH_DRIVE_VENDOR_ID, usb.vendorId)
-                .putInt(PREF_KEY_FLASH_DRIVE_PRODUCT_ID, usb.productId)
-                .apply()
-    }
-}
-
-fun getFlashDrive(context: Context): FlashDrive? {
-    val prefs = PreferenceManager.getDefaultSharedPreferences(context)
-    val name = prefs.getString(PREF_KEY_FLASH_DRIVE_NAME, null) ?: return null
-    val serialNumber = prefs.getString(PREF_KEY_FLASH_DRIVE_SERIAL_NUMBER, null)
-    val vendorId = prefs.getInt(PREF_KEY_FLASH_DRIVE_VENDOR_ID, -1)
-    val productId = prefs.getInt(PREF_KEY_FLASH_DRIVE_PRODUCT_ID, -1)
-    return FlashDrive(name, serialNumber, vendorId, productId)
-}
-
-
-/**
- * Generates and returns a new backup token while saving it as well.
- * Subsequent calls to [getBackupToken] will return this new token once saved.
- */
-fun getAndSaveNewBackupToken(context: Context): Long = Date().time.apply {
-    PreferenceManager.getDefaultSharedPreferences(context)
-            .edit()
-            .putLong(PREF_KEY_BACKUP_TOKEN, this)
-            .apply()
-}
-
-/**
- * Returns the current backup token or 0 if none exists.
- */
-fun getBackupToken(context: Context): Long {
-    return PreferenceManager.getDefaultSharedPreferences(context).getLong(PREF_KEY_BACKUP_TOKEN, 0L)
-}
-
-@Deprecated("Replaced by KeyManager#getBackupKey()")
-fun getBackupPassword(context: Context): String? {
-    return PreferenceManager.getDefaultSharedPreferences(context).getString(PREF_KEY_BACKUP_PASSWORD, null)
-}

app/src/main/java/com/stevesoltys/backup/transport/PluginManager.kt

@@ -8,8 +8,6 @@ import com.stevesoltys.backup.header.HeaderReaderImpl
 import com.stevesoltys.backup.header.HeaderWriterImpl
 import com.stevesoltys.backup.metadata.MetadataReaderImpl
 import com.stevesoltys.backup.metadata.MetadataWriterImpl
-import com.stevesoltys.backup.settings.getBackupToken
-import com.stevesoltys.backup.settings.getStorage
 import com.stevesoltys.backup.transport.backup.BackupCoordinator
 import com.stevesoltys.backup.transport.backup.FullBackup
 import com.stevesoltys.backup.transport.backup.InputFactory
@@ -24,9 +22,10 @@ import com.stevesoltys.backup.transport.restore.plugins.DocumentsProviderRestore
 
 class PluginManager(context: Context) {
 
-    // We can think about using an injection framework such as Dagger to simplify this.
+    // We can think about using an injection framework such as Dagger, Koin or Kodein to simplify this.
 
-    private val storage = DocumentsStorage(context, getStorage(context), getBackupToken(context))
+    private val settingsManager = (context.applicationContext as Backup).settingsManager
+    private val storage = DocumentsStorage(context, settingsManager)
 
     private val headerWriter = HeaderWriterImpl()
     private val headerReader = HeaderReaderImpl()
@@ -42,7 +41,7 @@ class PluginManager(context: Context) {
     private val fullBackup = FullBackup(backupPlugin.fullBackupPlugin, inputFactory, headerWriter, crypto)
     private val notificationManager = (context.applicationContext as Backup).notificationManager
 
-    internal val backupCoordinator = BackupCoordinator(context, backupPlugin, kvBackup, fullBackup, metadataWriter, notificationManager)
+    internal val backupCoordinator = BackupCoordinator(context, backupPlugin, kvBackup, fullBackup, metadataWriter, settingsManager, notificationManager)
 
 
     private val restorePlugin = DocumentsProviderRestorePlugin(storage)
@@ -50,6 +49,6 @@ class PluginManager(context: Context) {
     private val kvRestore = KVRestore(restorePlugin.kvRestorePlugin, outputFactory, headerReader, crypto)
     private val fullRestore = FullRestore(restorePlugin.fullRestorePlugin, outputFactory, headerReader, crypto)
 
-    internal val restoreCoordinator = RestoreCoordinator(context, restorePlugin, kvRestore, fullRestore, metadataReader)
+    internal val restoreCoordinator = RestoreCoordinator(settingsManager, restorePlugin, kvRestore, fullRestore, metadataReader)
 
 }

app/src/main/java/com/stevesoltys/backup/transport/backup/BackupCoordinator.kt

@@ -8,8 +8,7 @@ import android.os.ParcelFileDescriptor
 import android.util.Log
 import com.stevesoltys.backup.BackupNotificationManager
 import com.stevesoltys.backup.metadata.MetadataWriter
-import com.stevesoltys.backup.settings.getBackupToken
+import com.stevesoltys.backup.settings.SettingsManager
-import com.stevesoltys.backup.settings.getStorage
 import java.io.IOException
 import java.util.concurrent.TimeUnit.MINUTES
 
@@ -25,6 +24,7 @@ class BackupCoordinator(
         private val kv: KVBackup,
         private val full: FullBackup,
         private val metadataWriter: MetadataWriter,
+        private val settingsManager: SettingsManager,
         private val nm: BackupNotificationManager) {
 
     private var calledInitialize = false
@@ -56,7 +56,7 @@ class BackupCoordinator(
         Log.i(TAG, "Initialize Device!")
         return try {
             plugin.initializeDevice()
-            writeBackupMetadata(getBackupToken(context))
+            writeBackupMetadata(settingsManager.getBackupToken())
             // [finishBackup] will only be called when we return [TRANSPORT_OK] here
             // so we remember that we initialized successfully
             calledInitialize = true
@@ -100,8 +100,11 @@ class BackupCoordinator(
         Log.i(TAG, "Request incremental backup time. Returned $this")
     }
 
-    fun performIncrementalBackup(packageInfo: PackageInfo, data: ParcelFileDescriptor, flags: Int) =
+    fun performIncrementalBackup(packageInfo: PackageInfo, data: ParcelFileDescriptor, flags: Int): Int {
-            kv.performBackup(packageInfo, data, flags)
+        val result = kv.performBackup(packageInfo, data, flags)
+        if (result == TRANSPORT_OK) settingsManager.saveNewBackupTime()
+        return result
+    }
 
     // ------------------------------------------------------------------------------------
     // Full backup
@@ -126,8 +129,11 @@ class BackupCoordinator(
 
     fun checkFullBackupSize(size: Long) = full.checkFullBackupSize(size)
 
-    fun performFullBackup(targetPackage: PackageInfo, fileDescriptor: ParcelFileDescriptor, flags: Int) =
+    fun performFullBackup(targetPackage: PackageInfo, fileDescriptor: ParcelFileDescriptor, flags: Int): Int {
-            full.performFullBackup(targetPackage, fileDescriptor, flags)
+        val result = full.performFullBackup(targetPackage, fileDescriptor, flags)
+        if (result == TRANSPORT_OK) settingsManager.saveNewBackupTime()
+        return result
+    }
 
     fun sendBackupData(numBytes: Int) = full.sendBackupData(numBytes)
 
@@ -191,7 +197,7 @@ class BackupCoordinator(
         val defaultBackoff = MINUTES.toMillis(10)
 
         // back off if there's no storage set
-        val storage = getStorage(context) ?: return defaultBackoff
+        val storage = settingsManager.getStorage() ?: return defaultBackoff
         // don't back off if storage is not ejectable or available right now
         return if (!storage.ejectable || storage.getDocumentFile(context).isDirectory) noBackoff
         // otherwise back off

app/src/main/java/com/stevesoltys/backup/transport/backup/plugins/DocumentsStorage.kt

@@ -4,8 +4,8 @@ import android.content.Context
 import android.content.pm.PackageInfo
 import android.util.Log
 import androidx.documentfile.provider.DocumentFile
+import com.stevesoltys.backup.settings.SettingsManager
 import com.stevesoltys.backup.settings.Storage
-import com.stevesoltys.backup.settings.getAndSaveNewBackupToken
 import java.io.IOException
 import java.io.InputStream
 import java.io.OutputStream
@@ -19,7 +19,10 @@ private const val MIME_TYPE = "application/octet-stream"
 
 private val TAG = DocumentsStorage::class.java.simpleName
 
-class DocumentsStorage(private val context: Context, storage: Storage?, token: Long) {
+class DocumentsStorage(private val context: Context, private val settingsManager: SettingsManager) {
+
+    private val storage: Storage? = settingsManager.getStorage()
+    private val token: Long = settingsManager.getBackupToken()
 
     internal val rootBackupDir: DocumentFile? by lazy {
         val parent = storage?.getDocumentFile(context) ?: return@lazy null
@@ -36,7 +39,7 @@ class DocumentsStorage(private val context: Context, storage: Storage?, token: L
 
     private val currentToken: Long by lazy {
         if (token != 0L) token
-        else getAndSaveNewBackupToken(context).apply {
+        else settingsManager.getAndSaveNewBackupToken().apply {
             Log.d(TAG, "Using a fresh backup token: $this")
         }
     }

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

@@ -5,14 +5,13 @@ import android.app.backup.BackupTransport.TRANSPORT_OK
 import android.app.backup.RestoreDescription
 import android.app.backup.RestoreDescription.*
 import android.app.backup.RestoreSet
-import android.content.Context
 import android.content.pm.PackageInfo
 import android.os.ParcelFileDescriptor
 import android.util.Log
 import com.stevesoltys.backup.header.UnsupportedVersionException
 import com.stevesoltys.backup.metadata.DecryptionFailedException
 import com.stevesoltys.backup.metadata.MetadataReader
-import com.stevesoltys.backup.settings.getBackupToken
+import com.stevesoltys.backup.settings.SettingsManager
 import libcore.io.IoUtils.closeQuietly
 import java.io.IOException
 
@@ -23,7 +22,7 @@ private class RestoreCoordinatorState(
 private val TAG = RestoreCoordinator::class.java.simpleName
 
 internal class RestoreCoordinator(
-        private val context: Context,
+        private val settingsManager: SettingsManager,
         private val plugin: RestorePlugin,
         private val kv: KVRestore,
         private val full: FullRestore,
@@ -75,7 +74,7 @@ internal class RestoreCoordinator(
      * or 0 if there is no backup set available corresponding to the current device state.
      */
     fun getCurrentRestoreSet(): Long {
-        return getBackupToken(context)
+        return settingsManager.getBackupToken()
                 .apply { Log.i(TAG, "Got current restore set token: $this") }
     }
 

app/src/main/java/com/stevesoltys/backup/ui/storage/BackupStorageViewModel.kt

@@ -1,17 +1,14 @@
 package com.stevesoltys.backup.ui.storage
 
-import android.app.ActivityManager
 import android.app.Application
 import android.app.backup.BackupProgress
 import android.app.backup.IBackupObserver
 import android.net.Uri
 import android.os.UserHandle
-import android.os.UserManager
 import android.util.Log
 import androidx.annotation.WorkerThread
 import com.stevesoltys.backup.Backup
 import com.stevesoltys.backup.R
-import com.stevesoltys.backup.settings.getAndSaveNewBackupToken
 import com.stevesoltys.backup.transport.TRANSPORT_ID
 
 private val TAG = BackupStorageViewModel::class.java.simpleName
@@ -24,7 +21,7 @@ internal class BackupStorageViewModel(private val app: Application) : StorageVie
         saveStorage(uri)
 
         // use a new backup token
-        getAndSaveNewBackupToken(app)
+        settingsManager.getAndSaveNewBackupToken()
 
         // initialize the new location
         val observer = InitializationObserver()

app/src/main/java/com/stevesoltys/backup/ui/storage/StorageViewModel.kt

@@ -12,9 +12,11 @@ import android.util.Log
 import androidx.lifecycle.AndroidViewModel
 import androidx.lifecycle.LiveData
 import androidx.lifecycle.MutableLiveData
+import com.stevesoltys.backup.Backup
 import com.stevesoltys.backup.R
 import com.stevesoltys.backup.isMassStorage
-import com.stevesoltys.backup.settings.*
+import com.stevesoltys.backup.settings.FlashDrive
+import com.stevesoltys.backup.settings.Storage
 import com.stevesoltys.backup.transport.ConfigurableBackupTransportService
 import com.stevesoltys.backup.ui.LiveEvent
 import com.stevesoltys.backup.ui.MutableLiveEvent
@@ -23,6 +25,8 @@ private val TAG = StorageViewModel::class.java.simpleName
 
 internal abstract class StorageViewModel(private val app: Application) : AndroidViewModel(app), RemovableStorageListener {
 
+    protected val settingsManager = (app as Backup).settingsManager
+
     private val mStorageRoots = MutableLiveData<List<StorageRoot>>()
     internal val storageRoots: LiveData<List<StorageRoot>> get() = mStorageRoots
 
@@ -39,7 +43,8 @@ internal abstract class StorageViewModel(private val app: Application) : Android
 
     companion object {
         internal fun validLocationIsSet(context: Context): Boolean {
-            val storage = getStorage(context) ?: return false
+            val settingsManager = (context.applicationContext as Backup).settingsManager
+            val storage = settingsManager.getStorage() ?: return false
             if (storage.ejectable) return true
             return storage.getDocumentFile(context).isDirectory
         }
@@ -84,12 +89,15 @@ internal abstract class StorageViewModel(private val app: Application) : Android
             root.title
         }
         val storage = Storage(uri, name, root.supportsEject)
-        setStorage(app, storage)
+        settingsManager.setStorage(storage)
+
+        // reset time of last backup to "Never"
+        settingsManager.resetBackupTime()
 
         if (storage.ejectable) {
             val wasSaved = saveUsbDevice()
             // reset stored flash drive, if we did not update it
-            if (!wasSaved) setFlashDrive(app, null)
+            if (!wasSaved) settingsManager.setFlashDrive(null)
         }
 
         // stop backup service to be sure the old location will get updated
@@ -102,7 +110,7 @@ internal abstract class StorageViewModel(private val app: Application) : Android
         val manager = app.getSystemService(USB_SERVICE) as UsbManager
         manager.deviceList.values.forEach { device ->
             if (device.isMassStorage()) {
-                setFlashDrive(app, FlashDrive.from(device))
+                settingsManager.setFlashDrive(FlashDrive.from(device))
                 return true
             }
         }

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

@@ -31,6 +31,8 @@
     <string name="settings_backup_location_invalid">The chosen location can not be used.</string>
     <string name="settings_backup_location_none">None</string>
     <string name="settings_backup_location_internal">Internal Storage</string>
+    <string name="settings_backup_last_backup_never">Never</string>
+    <string name="settings_backup_location_summary">%s · Last Backup %s</string>
     <string name="settings_info">All backups are encrypted on your phone. To restore from backup you will need your 12-word recovery code.</string>
     <string name="settings_auto_restore_title">Automatic restore</string>
     <string name="settings_auto_restore_summary">When reinstalling an app, restore backed up settings and data</string>

app/src/test/java/com/stevesoltys/backup/transport/CoordinatorIntegrationTest.kt

@@ -43,14 +43,14 @@ internal class CoordinatorIntegrationTest : TransportTest() {
     private val fullBackupPlugin = mockk<FullBackupPlugin>()
     private val fullBackup = FullBackup(fullBackupPlugin, inputFactory, headerWriter, cryptoImpl)
     private val notificationManager = mockk<BackupNotificationManager>()
-    private val backup = BackupCoordinator(context, backupPlugin, kvBackup, fullBackup, metadataWriter, notificationManager)
+    private val backup = BackupCoordinator(context, backupPlugin, kvBackup, fullBackup, metadataWriter, settingsManager, notificationManager)
 
     private val restorePlugin = mockk<RestorePlugin>()
     private val kvRestorePlugin = mockk<KVRestorePlugin>()
     private val kvRestore = KVRestore(kvRestorePlugin, outputFactory, headerReader, cryptoImpl)
     private val fullRestorePlugin = mockk<FullRestorePlugin>()
     private val fullRestore = FullRestore(fullRestorePlugin, outputFactory, headerReader, cryptoImpl)
-    private val restore = RestoreCoordinator(context, restorePlugin, kvRestore, fullRestore, metadataReader)
+    private val restore = RestoreCoordinator(settingsManager, restorePlugin, kvRestore, fullRestore, metadataReader)
 
     private val backupDataInput = mockk<BackupDataInput>()
     private val fileDescriptor = mockk<ParcelFileDescriptor>(relaxed = true)
@@ -91,6 +91,7 @@ internal class CoordinatorIntegrationTest : TransportTest() {
             appData2.size
         }
         every { kvBackupPlugin.getOutputStreamForRecord(packageInfo, key264) } returns bOutputStream2
+        every { settingsManager.saveNewBackupTime() } just Runs
 
         // start and finish K/V backup
         assertEquals(TRANSPORT_OK, backup.performIncrementalBackup(packageInfo, fileDescriptor, 0))
@@ -130,6 +131,7 @@ internal class CoordinatorIntegrationTest : TransportTest() {
         every { fullBackupPlugin.getOutputStream(packageInfo) } returns bOutputStream
         every { inputFactory.getInputStream(fileDescriptor) } returns bInputStream
         every { fullBackupPlugin.getQuota() } returns DEFAULT_QUOTA_FULL_BACKUP
+        every { settingsManager.saveNewBackupTime() } just Runs
 
         // perform backup to output stream
         assertEquals(TRANSPORT_OK, backup.performFullBackup(packageInfo, fileDescriptor, 0))

app/src/test/java/com/stevesoltys/backup/transport/TransportTest.kt

@@ -4,6 +4,7 @@ import android.content.Context
 import android.content.pm.PackageInfo
 import android.util.Log
 import com.stevesoltys.backup.crypto.Crypto
+import com.stevesoltys.backup.settings.SettingsManager
 import io.mockk.every
 import io.mockk.mockk
 import io.mockk.mockkStatic
@@ -14,6 +15,7 @@ import org.junit.jupiter.api.TestInstance.Lifecycle.PER_METHOD
 abstract class TransportTest {
 
     protected val crypto = mockk<Crypto>()
+    protected val settingsManager = mockk<SettingsManager>()
     protected val context = mockk<Context>(relaxed = true)
 
     protected val packageInfo = PackageInfo().apply { packageName = "org.example" }

app/src/test/java/com/stevesoltys/backup/transport/backup/BackupCoordinatorTest.kt

@@ -23,14 +23,15 @@ internal class BackupCoordinatorTest: BackupTest() {
     private val metadataWriter = mockk<MetadataWriter>()
     private val notificationManager = mockk<BackupNotificationManager>()
 
-    private val backup = BackupCoordinator(context, plugin, kv, full, metadataWriter, notificationManager)
+    private val backup = BackupCoordinator(context, plugin, kv, full, metadataWriter, settingsManager, notificationManager)
 
     private val metadataOutputStream = mockk<OutputStream>()
 
     @Test
     fun `device initialization succeeds and delegates to plugin`() {
         every { plugin.initializeDevice() } just Runs
-        expectWritingMetadata(0L)
+        every { settingsManager.getBackupToken() } returns token
+        expectWritingMetadata(token)
         every { kv.hasState() } returns false
         every { full.hasState() } returns false
 

app/src/test/java/com/stevesoltys/backup/transport/restore/RestoreCoordinatorTest.kt

@@ -27,7 +27,7 @@ internal class RestoreCoordinatorTest : TransportTest() {
     private val full = mockk<FullRestore>()
     private val metadataReader = mockk<MetadataReader>()
 
-    private val restore = RestoreCoordinator(context, plugin, kv, full, metadataReader)
+    private val restore = RestoreCoordinator(settingsManager, plugin, kv, full, metadataReader)
 
     private val token = Random.nextLong()
     private val inputStream = mockk<InputStream>()
@@ -56,8 +56,8 @@ internal class RestoreCoordinatorTest : TransportTest() {
 
     @Test
     fun `getCurrentRestoreSet() delegates to plugin`() {
-        // We don't mock the SettingsManager, so the default value is returned here
+        every { settingsManager.getBackupToken() } returns token
-        assertEquals(0L, restore.getCurrentRestoreSet())
+        assertEquals(token, restore.getCurrentRestoreSet())
     }
 
     @Test