Ask for a review when a document from another app is put down

app/src/main/java/app/opendocument/droid/ui/activity/DocumentFragment.kt

@@ -942,6 +942,7 @@ class DocumentFragment : Fragment(), DocumentLoader.Listener {
             freshOpenPending = false
 
             ReviewInvitation.recordDocumentOpen(activity)
+            (activity as? MainActivity)?.onDocumentShown()
         }
     }
 

app/src/main/java/app/opendocument/droid/ui/activity/MainActivity.kt

@@ -102,14 +102,33 @@ class MainActivity : AppCompatActivity() {
                 // an externally opened document leaves the app rather than the document, and
                 // carries unsaved edits out just the same
                 confirmLeavingEdits {
-                    // fall through to the default behavior (close the activity)
-                    isEnabled = false
-                    onBackPressedDispatcher.onBackPressed()
-                    isEnabled = true
+                    // the only moment a document opened from another app is put down again
+                    val asked =
+                        documentFragment != null &&
+                            preparedReview?.showIfReady(
+                                onAsked = { ReviewInvitation.recordAsk(this@MainActivity) },
+                                onDone = { leaveApp() },
+                            ) == true
+                    preparedReview = null
+
+                    if (!asked) {
+                        leaveApp()
+                    }
                 }
             }
         }
 
+    /** Falls through to the default back behavior, which closes the activity. */
+    private fun leaveApp() {
+        if (isFinishing || isDestroyed) {
+            return
+        }
+
+        backCallback.isEnabled = false
+        onBackPressedDispatcher.onBackPressed()
+        backCallback.isEnabled = true
+    }
+
     // kept because onPause has to stop it
     private var ttsActionMode: TtsActionModeCallback? = null
 
@@ -145,6 +164,9 @@ class MainActivity : AppCompatActivity() {
     // lands would pass isEarned again. never reset: one hand-off per activity is plenty
     private var reviewRequested = false
 
+    // fetched while an externally opened document is read: back must not wait on the network
+    private var preparedReview: InAppReview.Prepared? = null
+
     /**
      * Loads and saves the open document. Scoped to the activity, so it survives a configuration
      * change and [DocumentFragment] finds it already there rather than waiting for a binding.
@@ -870,6 +892,16 @@ class MainActivity : AppCompatActivity() {
             .show()
     }
 
+    /** Called once a fresh open has rendered. */
+    fun onDocumentShown() {
+        if (!documentOpenedExternally || reviewRequested || !ReviewInvitation.isEarned(this)) {
+            return
+        }
+
+        reviewRequested = true
+        preparedReview = InAppReview.prepare(this, analyticsManager)
+    }
+
     /** Deliberately not from [closeFailedDocument], the last moment on earth to ask for stars. */
     private fun askForReviewIfEarned() {
         if (reviewRequested || !ReviewInvitation.isEarned(this)) {

app/src/noReview/java/app/opendocument/droid/nonfree/InAppReview.kt

@@ -6,4 +6,11 @@ import android.app.Activity
 object InAppReview {
 
     fun request(activity: Activity, analyticsManager: AnalyticsManager, onAsked: () -> Unit) {}
+
+    fun prepare(activity: Activity, analyticsManager: AnalyticsManager): Prepared = Prepared()
+
+    class Prepared {
+
+        fun showIfReady(onAsked: () -> Unit, onDone: () -> Unit): Boolean = false
+    }
 }

app/src/review/java/app/opendocument/droid/nonfree/InAppReview.kt

@@ -1,6 +1,7 @@
 package app.opendocument.droid.nonfree
 
 import android.app.Activity
+import com.google.android.play.core.review.ReviewInfo
 import com.google.android.play.core.review.ReviewManagerFactory
 
 /**
@@ -34,4 +35,47 @@ object InAppReview {
             }
         }
     }
+
+    /**
+     * Fetches the sheet ahead of the moment to show it, so that moment does not wait on the
+     * network.
+     */
+    fun prepare(activity: Activity, analyticsManager: AnalyticsManager): Prepared {
+        val prepared = Prepared(activity, analyticsManager)
+        analyticsManager.report("in_app_review_eligible")
+
+        prepared.manager.requestReviewFlow().addOnCompleteListener { task ->
+            if (task.isSuccessful) {
+                prepared.reviewInfo = task.result
+            } else {
+                analyticsManager.report("in_app_review_error")
+            }
+        }
+
+        return prepared
+    }
+
+    class Prepared
+    internal constructor(
+        private val activity: Activity,
+        private val analyticsManager: AnalyticsManager,
+    ) {
+        internal val manager = ReviewManagerFactory.create(activity)
+        internal var reviewInfo: ReviewInfo? = null
+
+        /** False when the sheet has not arrived yet - then [onDone] does not run. */
+        fun showIfReady(onAsked: () -> Unit, onDone: () -> Unit): Boolean {
+            val reviewInfo = reviewInfo ?: return false
+
+            analyticsManager.report("in_app_review_start")
+            onAsked()
+
+            manager.launchReviewFlow(activity, reviewInfo).addOnCompleteListener {
+                analyticsManager.report("in_app_review_done")
+                onDone()
+            }
+
+            return true
+        }
+    }
 }