Wire Rust resume/pause work on app lifecycle changes

ET-4565

app/src/main/kotlin/ch/protonmail/android/initializer/background/BackgroundExecutionInitializer.kt

@@ -46,6 +46,6 @@ internal class BackgroundExecutionInitializer : Initializer<Unit> {
     @InstallIn(SingletonComponent::class)
     interface BackgroundExecutionEntryPoint {
 
-        fun lifecycleObserver(): BackgroundExecutionLifecycleObserver
+        fun lifecycleObserver(): RustWorkLifecycleObserver
     }
 }

app/src/main/kotlin/ch/protonmail/android/initializer/background/RustWorkLifecycleObserver.kt

@@ -21,17 +21,29 @@ package ch.protonmail.android.initializer.background
 import androidx.lifecycle.DefaultLifecycleObserver
 import androidx.lifecycle.LifecycleOwner
 import ch.protonmail.android.mailsession.data.background.BackgroundExecutionWorkScheduler
+import ch.protonmail.android.mailsession.data.repository.MailSessionRepository
 import javax.inject.Inject
 
-class BackgroundExecutionLifecycleObserver @Inject constructor(
+class RustWorkLifecycleObserver @Inject constructor(
+    private val mailSessionRepository: MailSessionRepository,
     private val backgroundExecutionWorkScheduler: BackgroundExecutionWorkScheduler
 ) : DefaultLifecycleObserver {
 
     override fun onResume(owner: LifecycleOwner) {
         backgroundExecutionWorkScheduler.cancelPendingWork()
+        resumeWork()
     }
 
     override fun onStop(owner: LifecycleOwner) {
+        pauseWork()
         backgroundExecutionWorkScheduler.scheduleWork()
     }
+
+    private fun pauseWork() {
+        mailSessionRepository.getMailSession().pauseWork()
+    }
+
+    private fun resumeWork() {
+        mailSessionRepository.getMailSession().resumeWork()
+    }
 }

app/src/test/kotlin/ch/protonmail/android/initializer/background/RustWorkLifecycleObserverTest.kt

@@ -20,6 +20,7 @@ package ch.protonmail.android.initializer.background
 
 import androidx.lifecycle.LifecycleOwner
 import ch.protonmail.android.mailsession.data.background.BackgroundExecutionWorkScheduler
+import ch.protonmail.android.mailsession.data.repository.MailSessionRepository
 import io.mockk.coEvery
 import io.mockk.coVerify
 import io.mockk.confirmVerified
@@ -30,34 +31,41 @@ import io.mockk.runs
 import io.mockk.verify
 import kotlin.test.Test
 
-internal class BackgroundExecutionLifecycleObserverTest {
+internal class RustWorkLifecycleObserverTest {
 
     private val scheduler = mockk<BackgroundExecutionWorkScheduler>()
-    private val observer = BackgroundExecutionLifecycleObserver(scheduler)
+    private val mailSessionRepository = mockk<MailSessionRepository>()
+    private val observer = RustWorkLifecycleObserver(mailSessionRepository, scheduler)
 
     private val lifecycleOwner = mockk<LifecycleOwner>()
 
     @Test
-    fun `should cancel background work when onResume is triggered`() {
+    fun `should cancel background execution and resume work when onResume is triggered`() {
         // Given
         every { scheduler.cancelPendingWork() } just runs
+        every { mailSessionRepository.getMailSession().resumeWork() } just runs
+
         // When
         observer.onResume(lifecycleOwner)
 
         // Then
         verify(exactly = 1) { scheduler.cancelPendingWork() }
-        confirmVerified(scheduler)
+        coVerify(exactly = 1) { mailSessionRepository.getMailSession().resumeWork() }
+        confirmVerified(mailSessionRepository, scheduler)
     }
 
     @Test
-    fun `should schedule background work when onStop is triggered`() {
+    fun `should schedule background execution and pause work when onStop is triggered`() {
         // Given
         coEvery { scheduler.scheduleWork() } just runs
+        every { mailSessionRepository.getMailSession().pauseWork() } just runs
+
         // When
         observer.onStop(lifecycleOwner)
 
         // Then
         coVerify(exactly = 1) { scheduler.scheduleWork() }
-        confirmVerified(scheduler)
+        coVerify(exactly = 1) { mailSessionRepository.getMailSession().pauseWork() }
+        confirmVerified(mailSessionRepository, scheduler)
     }
 }

mail-session/data/src/main/kotlin/ch/protonmail/android/mailsession/data/wrapper/MailSessionWrapper.kt

@@ -149,6 +149,16 @@ class MailSessionWrapper(private val mailSession: MailSession) {
 
     fun startBackgroundTask(callback: BackgroundExecutionCallback) = mailSession.startBackgroundExecution(callback)
 
+    /**
+     * Used to pause work when the app is sent to the background.
+     */
+    fun pauseWork() = mailSession.pauseWork()
+
+    /**
+     * Used to resume work when the app is brought back to the foreground.
+     */
+    fun resumeWork() = mailSession.resumeWork()
+
     suspend fun newLoginFlow(): Either<DataError, LoginFlowWrapper> {
         return when (val result = mailSession.newLoginFlow()) {
             is MailSessionNewLoginFlowResult.Ok -> LoginFlowWrapper(result.v1).right()