Increase mailbox views count when closing a detail screen

This count will be used to define when a user can be presented with the
"rate app" dialog. We increase the count when going back from the detail
rather than at some point in the mailbox screen's lifecycle to avoid the
case where the dialog is shown when resuming mailbox from the
background.

MAILAND-3071

app/src/main/java/ch/protonmail/android/details/presentation/ui/MessageDetailsActivity.kt

@@ -62,6 +62,7 @@ import ch.protonmail.android.events.DownloadEmbeddedImagesEvent
 import ch.protonmail.android.events.DownloadedAttachmentEvent
 import ch.protonmail.android.events.PostPhishingReportEvent
 import ch.protonmail.android.events.Status
+import ch.protonmail.android.feature.rating.ShowReviewAppInMemoryRepository
 import ch.protonmail.android.jobs.PostSpamJob
 import ch.protonmail.android.labels.domain.model.LabelId
 import ch.protonmail.android.labels.domain.model.LabelType
@@ -122,6 +123,9 @@ internal class MessageDetailsActivity : BaseStoragePermissionActivity() {
     @Inject
     lateinit var accountSettingsRepository: AccountSettingsRepository
 
+    @Inject
+    lateinit var showReviewAppRepository: ShowReviewAppInMemoryRepository
+
     private lateinit var messageOrConversationId: String
     private lateinit var messageExpandableAdapter: MessageDetailsAdapter
     private lateinit var primaryBaseActivity: Context
@@ -358,6 +362,11 @@ internal class MessageDetailsActivity : BaseStoragePermissionActivity() {
         mApp.bus.unregister(this)
     }
 
+    override fun onBackPressed() {
+        showReviewAppRepository.recordMailboxScreenView()
+        super.onBackPressed()
+    }
+
     override fun onOptionsItemSelected(item: MenuItem): Boolean {
         when (item.itemId) {
             android.R.id.home -> {

app/src/main/java/ch/protonmail/android/feature/rating/ShowReviewAppInMemoryRepository.kt

@@ -22,10 +22,16 @@ package ch.protonmail.android.feature.rating
 import androidx.annotation.VisibleForTesting
 import me.proton.core.domain.entity.UserId
 import me.proton.core.featureflag.domain.entity.FeatureFlag
+import timber.log.Timber
 import javax.inject.Inject
+import javax.inject.Singleton
 
+@Singleton
 class ShowReviewAppInMemoryRepository @Inject constructor() {
 
+    @VisibleForTesting
+    var mailboxScreenViews: Int = 0
+
     @VisibleForTesting
     val featureFlags: MutableMap<UserId, Boolean> = mutableMapOf()
 
@@ -33,4 +39,22 @@ class ShowReviewAppInMemoryRepository @Inject constructor() {
         val userId = featureFlag.userId ?: return
         featureFlags[userId] = featureFlag.value
     }
+
+    fun recordMailboxScreenView() {
+        mailboxScreenViews++
+        Timber.d("Recording mailbox screen view: count $mailboxScreenViews")
+    }
+
+    fun shouldShowRateAppDialog(userId: UserId): Boolean {
+        val isFlagEnabled = featureFlags[userId] ?: false
+        if (!isFlagEnabled) {
+            return false
+        }
+        return mailboxScreenViews >= MailboxScreenViewsThreshold
+    }
+
+    companion object {
+
+        private const val MailboxScreenViewsThreshold = 2
+    }
 }

app/src/test/java/ch/protonmail/android/feature/rating/ShowReviewAppInMemoryRepositoryTest.kt

@@ -21,6 +21,7 @@ package ch.protonmail.android.feature.rating
 
 import ch.protonmail.android.testdata.UserTestData
 import kotlinx.coroutines.test.runTest
+import me.proton.core.domain.entity.UserId
 import me.proton.core.featureflag.domain.entity.FeatureFlag
 import me.proton.core.featureflag.domain.entity.FeatureId
 import me.proton.core.featureflag.domain.entity.Scope
@@ -46,4 +47,77 @@ class ShowReviewAppInMemoryRepositoryTest {
         assertEquals(expected, showReviewAppRepository.featureFlags)
     }
 
+    @Test
+    fun increaseMailboxScreenViewsCounterWhenRecordMailboxScreenViewIsCalled() = runTest {
+        // when
+        showReviewAppRepository.recordMailboxScreenView()
+
+        // then
+        assertEquals(1, showReviewAppRepository.mailboxScreenViews)
+    }
+
+    @Test
+    fun shouldShowRateAppDialogIsTrueWhenFeatureFlagIsTrueAndMailboxScreenHasBeenSeenMoreTimesThanThreshold() =
+        runTest {
+            // given
+            val userId = UserTestData.userId
+            mockFeatureFlagValue(userId, true)
+            mockScreenViews(2)
+
+            // when
+            val actual = showReviewAppRepository.shouldShowRateAppDialog(userId)
+
+            // then
+            assertEquals(true, actual)
+        }
+
+    @Test
+    fun shouldShowRateAppDialogIsFalseWhenFeatureFlagIsFalse() = runTest {
+        // given
+        val userId = UserTestData.userId
+        mockFeatureFlagValue(userId, false)
+        mockScreenViews(2)
+
+        // when
+        val actual = showReviewAppRepository.shouldShowRateAppDialog(userId)
+
+        // then
+        assertEquals(false, actual)
+    }
+
+    @Test
+    fun shouldShowRateAppDialogIsFalseWhenNoFeatureFlagExistsForThisUser() = runTest {
+        // given
+        val userId = UserTestData.userId
+        mockScreenViews(2)
+
+        // when
+        val actual = showReviewAppRepository.shouldShowRateAppDialog(userId)
+
+        // then
+        assertEquals(false, actual)
+    }
+
+    @Test
+    fun shouldShowRateAppDialogIsFalseWhenMailboxScreenHaveNotBeenSeenUpToThresholdTimes() = runTest {
+        // given
+        val userId = UserTestData.userId
+        mockFeatureFlagValue(userId, true)
+        mockScreenViews(1)
+
+        // when
+        val actual = showReviewAppRepository.shouldShowRateAppDialog(userId)
+
+        // then
+        assertEquals(false, actual)
+    }
+
+    private fun mockScreenViews(count: Int) {
+        showReviewAppRepository.mailboxScreenViews = count
+    }
+
+    private fun mockFeatureFlagValue(userId: UserId, isEnabled: Boolean) {
+        showReviewAppRepository.featureFlags[userId] = isEnabled
+    }
+
 }