Issue 1588 restrictions on background starts (#1670)

* Resolved ForegroundServiceStartNotAllowedException for MessagesSenderWorker.| #1588

* Modified PassPhrasesInRAMService to support "restrictions on background starts".| #1588

* Modified MessagesSenderWorker to support "restrictions on background starts".| #1588

* Modified logic in MessagesSenderWorker.kt.| #1588

FlowCrypt/src/main/java/com/flowcrypt/email/jetpack/workmanager/MessagesSenderWorker.kt

@@ -6,13 +6,16 @@
 package com.flowcrypt.email.jetpack.workmanager
 
 import android.accounts.AuthenticatorException
+import android.app.ForegroundServiceStartNotAllowedException
 import android.content.Context
+import android.os.Build
 import androidx.core.app.NotificationCompat
 import androidx.work.Constraints
 import androidx.work.ExistingWorkPolicy
 import androidx.work.ForegroundInfo
 import androidx.work.NetworkType
 import androidx.work.OneTimeWorkRequestBuilder
+import androidx.work.OutOfQuotaPolicy
 import androidx.work.WorkManager
 import androidx.work.WorkerParameters
 import com.flowcrypt.email.Constants
@@ -102,8 +105,20 @@ class MessagesSenderWorker(context: Context, params: WorkerParameters) :
           )
         )
 
-        if (!CollectionUtils.isEmpty(queuedMsgs) || !CollectionUtils.isEmpty(sentButNotSavedMsgs)) {
-          setForeground(genForegroundInfo(account))
+        if (queuedMsgs.isNotEmpty() || sentButNotSavedMsgs.isNotEmpty()) {
+          try {
+            setForeground(genForegroundInfoInternal(account.email, false))
+          } catch (e: IllegalStateException) {
+            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S) {
+              if (e is ForegroundServiceStartNotAllowedException) {
+                //see for details https://developer.android.com/topic/libraries/architecture/workmanager/how-to/define-work#coroutineworker
+                LogsUtil.d(
+                  TAG, "It seems the app started this worker while running in the background." +
+                      " We can't show a notification in that case."
+                )
+              }
+            }
+          }
 
           if (account.useAPI) {
             when (account.accountType) {
@@ -157,19 +172,37 @@ class MessagesSenderWorker(context: Context, params: WorkerParameters) :
       }
     }
 
-  private fun genForegroundInfo(account: AccountEntity): ForegroundInfo {
-    val title = applicationContext.getString(R.string.sending_email)
+  override suspend fun getForegroundInfo(): ForegroundInfo {
+    /*we should add implementation of this method if we use
+    setExpedited(OutOfQuotaPolicy.RUN_AS_NON_EXPEDITED_WORK_REQUEST).
+    Android 11 and less uses it to show a notification*/
+    return genForegroundInfoInternal()
+  }
+
+  private fun genForegroundInfoInternal(
+    email: String? = null,
+    isDefault: Boolean = true
+  ): ForegroundInfo {
     val notification = NotificationCompat.Builder(
       applicationContext,
       NotificationChannelManager.CHANNEL_ID_SYNC
     )
-      .setContentTitle(title)
-      .setTicker(title)
-      .setSmallIcon(R.drawable.ic_sending_email_grey_24dp)
-      .setOngoing(true)
-      .setSubText(account.email)
       .setProgress(0, 0, true)
-      .build()
+      .setOngoing(true)
+      .setForegroundServiceBehavior(NotificationCompat.FOREGROUND_SERVICE_IMMEDIATE)
+      .apply {
+        val title = applicationContext.getString(
+          if (isDefault) R.string.synchronization else R.string.sending_email
+        )
+        setContentTitle(title)
+        if (isDefault) {
+          setSmallIcon(R.drawable.ic_synchronization_grey_24dp)
+        } else {
+          setTicker(title)
+          setSmallIcon(R.drawable.ic_sending_email_grey_24dp)
+          setSubText(email)
+        }
+      }.build()
 
     return ForegroundInfo(NOTIFICATION_ID, notification)
   }
@@ -513,7 +546,7 @@ class MessagesSenderWorker(context: Context, params: WorkerParameters) :
 
   companion object {
     private val TAG = MessagesSenderWorker::class.java.simpleName
-    private const val NOTIFICATION_ID = -10000
+    private const val NOTIFICATION_ID = R.id.notification_id_sending_msgs_worker
     val NAME = MessagesSenderWorker::class.java.simpleName
 
     fun enqueue(context: Context, forceSending: Boolean = false) {
@@ -528,6 +561,16 @@ class MessagesSenderWorker(context: Context, params: WorkerParameters) :
           if (forceSending) ExistingWorkPolicy.REPLACE else ExistingWorkPolicy.KEEP,
           OneTimeWorkRequestBuilder<MessagesSenderWorker>()
             .setConstraints(constraints)
+            .apply {
+              if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S) {
+                /*we have to use it due to
+                 https://developer.android.com/guide/components/foreground-services#background-start-restrictions
+                 We don't use it by default to prevent displaying a notification every time
+                 when this job will be started. We should try to show a notification only if we have
+                 at least one outgoing message that is actively sending*/
+                setExpedited(OutOfQuotaPolicy.RUN_AS_NON_EXPEDITED_WORK_REQUEST)
+              }
+            }
             .build()
         )
     }

FlowCrypt/src/main/java/com/flowcrypt/email/service/PassPhrasesInRAMService.kt

@@ -5,10 +5,13 @@
 
 package com.flowcrypt.email.service
 
+import android.app.ForegroundServiceStartNotAllowedException
 import android.app.Notification
 import android.app.PendingIntent
 import android.content.Context
 import android.content.Intent
+import android.os.Build
+import androidx.core.app.NotificationCompat
 import androidx.lifecycle.lifecycleScope
 import com.flowcrypt.email.R
 import com.flowcrypt.email.model.KeysStorage
@@ -18,7 +21,6 @@ import com.flowcrypt.email.ui.notifications.NotificationChannelManager
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.delay
 import kotlinx.coroutines.flow.Flow
-import kotlinx.coroutines.flow.collect
 import kotlinx.coroutines.flow.flow
 import kotlinx.coroutines.flow.flowOn
 import kotlinx.coroutines.isActive
@@ -38,26 +40,13 @@ class PassPhrasesInRAMService : BaseLifecycleService() {
   override fun onCreate() {
     super.onCreate()
     keysStorage = KeysStorageImpl.getInstance(applicationContext)
-    runAsForeground()
     runChecking()
   }
 
-  private fun runAsForeground() {
-    val pendingIntent: PendingIntent =
-      Intent(this, EmailManagerActivity::class.java).let { notificationIntent ->
-        PendingIntent.getActivity(this, 0, notificationIntent, PendingIntent.FLAG_IMMUTABLE)
-      }
-
-    val notification: Notification = Notification.Builder(
-      this,
-      NotificationChannelManager.CHANNEL_ID_SILENT
-    )
-      .setContentTitle(getString(R.string.active_passphrase_session))
-      .setSmallIcon(R.drawable.ic_baseline_password_24dp)
-      .setContentIntent(pendingIntent)
-      .build()
-
-    startForeground(R.id.notification_id_passphrase_service, notification)
+  override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
+    val superStartedState = super.onStartCommand(intent, flags, startId)
+    startForeground(R.id.notification_id_passphrase_service, prepareNotification())
+    return superStartedState
   }
 
   private fun runChecking() {
@@ -79,6 +68,22 @@ class PassPhrasesInRAMService : BaseLifecycleService() {
     }.flowOn(Dispatchers.Default)
   }
 
+  private fun prepareNotification(): Notification {
+    return NotificationCompat.Builder(this, NotificationChannelManager.CHANNEL_ID_SILENT)
+      .setContentTitle(getString(R.string.active_passphrase_session))
+      .setSmallIcon(R.drawable.ic_baseline_password_24dp)
+      .setContentIntent(
+        PendingIntent.getActivity(
+          this,
+          0,
+          Intent(this, EmailManagerActivity::class.java),
+          PendingIntent.FLAG_IMMUTABLE
+        )
+      )
+      .setForegroundServiceBehavior(NotificationCompat.FOREGROUND_SERVICE_IMMEDIATE)
+      .build()
+  }
+
   companion object {
     /**
      * We will run checking every minute.
@@ -92,7 +97,17 @@ class PassPhrasesInRAMService : BaseLifecycleService() {
      */
     fun start(context: Context) {
       val startEmailServiceIntent = Intent(context, PassPhrasesInRAMService::class.java)
-      context.startForegroundService(startEmailServiceIntent)
+      try {
+        context.startForegroundService(startEmailServiceIntent)
+      } catch (e: Exception) {
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S) {
+          if (e is ForegroundServiceStartNotAllowedException) {
+            /*Because this service should be restarted by the system we can skip this exception.
+             It seems this service was started manually after the app crash via the trigger.*/
+            e.printStackTrace()
+          }
+        } else throw e
+      }
     }
 
     /**

FlowCrypt/src/main/res/drawable/ic_synchronization_grey_24dp.xml

@@ -0,0 +1,15 @@
+<!--
+  ~ © 2016-present FlowCrypt a.s. Limitations apply. Contact [email protected]
+  ~ Contributors: denbond7
+  -->
+
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:tint="#B6B6B6"
+    android:viewportWidth="24"
+    android:viewportHeight="24">
+    <path
+        android:fillColor="#FF000000"
+        android:pathData="M12,4L12,1L8,5l4,4L12,6c3.31,0 6,2.69 6,6 0,1.01 -0.25,1.97 -0.7,2.8l1.46,1.46C19.54,15.03 20,13.57 20,12c0,-4.42 -3.58,-8 -8,-8zM12,18c-3.31,0 -6,-2.69 -6,-6 0,-1.01 0.25,-1.97 0.7,-2.8L5.24,7.74C4.46,8.97 4,10.43 4,12c0,4.42 3.58,8 8,8v3l4,-4 -4,-4v3z" />
+</vector>

FlowCrypt/src/main/res/values-ru/strings.xml

@@ -487,4 +487,5 @@
     <string name="one_special_character_eg">один из специальных символов: &amp;"#-'_%-@,;:!*()</string>
     <string name="warning_use_subject_as_password">Пожалуйста, не прописывайте пароль в тему сообщения. Передача пароля по электронной почте далает бессмысленным шифрование на основе пароля.\n\nВы можете попросить получателя также установить %1$s, сообщения между пользователями %1$s не нуждаются в пароле.</string>
     <string name="warning_use_private_key_pass_phrase_as_password">Пожалуйста, не используйте Вашу ключевую фразу в качестве пароля для даного сообщения.\n\nВы должны придумать какой-нибудь другой уникальный пароль, которым Вы можете поделиться с получателем.</string>
+    <string name="synchronization">Синхронизация&#8230;</string>
 </resources>

FlowCrypt/src/main/res/values/ids.xml

@@ -37,4 +37,5 @@
     <item name="notification_id_has_failed_outgoing_msgs" type="id" />
     <item name="notification_id_auth_failure" type="id" />
     <item name="notification_id_passphrase_service" type="id" />
+    <item name="notification_id_sending_msgs_worker" type="id" />
 </resources>

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

@@ -573,4 +573,5 @@
     <string name="one_special_character_eg">one special character eg &amp;"#-'_%-@,;:!*()</string>
     <string name="warning_use_subject_as_password">Please do not include the password in the email subject. Sharing password over email undermines password based encryption.\n\nYou can ask the recipient to also install %1$s, messages between %1$s users don\'t need a password.</string>
     <string name="warning_use_private_key_pass_phrase_as_password">Please do not use your private key pass phrase as a password for this message.\n\nYou should come up with some other unique password that you can share with a recipient.</string>
+    <string name="synchronization">Syncing&#8230;</string>
 </resources>