Improve re-register flow for numberless account.

feature/registration/src/main/java/org/signal/registration/screens/phonenumber/PhoneNumberEntryScreen.kt

@@ -82,6 +82,7 @@ import org.signal.core.ui.compose.Scaffolds
 import org.signal.core.ui.compose.SignalIcons
 import org.signal.core.util.Util
 import org.signal.core.util.logging.Log
+import org.signal.registration.PendingRestoreOption
 import org.signal.registration.R
 import org.signal.registration.RegistrationDependencies
 import org.signal.registration.screens.OnePaneRegistrationScaffold
@@ -413,7 +414,15 @@ private fun NextButton(
         enabled = !state.showSpinner,
         modifier = Modifier.testTag(TestTags.PHONE_NUMBER_REGISTER_WITHOUT_NUMBER_BUTTON)
       ) {
-        Text(stringResource(R.string.RegistrationActivity_register_without_number))
+        Text(
+          stringResource(
+            if (state.hasExistingAccount) {
+              R.string.RegistrationActivity_use_account_id
+            } else {
+              R.string.RegistrationActivity_register_without_number
+            }
+          )
+        )
       }
 
       Spacer(modifier = Modifier.weight(1f))
@@ -646,6 +655,20 @@ private fun PhoneNumberScreenRegisterWithoutNumberPreview() {
   }
 }
 
+@AllDevicePreviews
+@Composable
+private fun PhoneNumberScreenUseAccountIdPreview() {
+  Previews.Preview {
+    PhoneNumberScreen(
+      state = PhoneNumberEntryState(
+        isPhoneNumberlessRegistrationAvailable = true,
+        pendingRestoreOption = PendingRestoreOption.RemoteBackup
+      ),
+      onEvent = {}
+    )
+  }
+}
+
 @AllDevicePreviews
 @Composable
 private fun PhoneNumberScreenAccountIdPreview() {

feature/registration/src/main/java/org/signal/registration/screens/phonenumber/PhoneNumberEntryState.kt

@@ -52,6 +52,10 @@ data class PhoneNumberEntryState(
       null
     }
 
+  /** Whether the user already told us they have an account to restore, which lets us skip past the Signal Login purchase screen. */
+  val hasExistingAccount: Boolean
+    get() = pendingRestoreOption != null
+
   /** Whether what has been entered is complete enough to submit, be it a phone number or an account ID. */
   val isNextEnabled: Boolean
     get() {

feature/registration/src/main/java/org/signal/registration/screens/phonenumber/PhoneNumberEntryViewModel.kt

@@ -151,7 +151,11 @@ class PhoneNumberEntryViewModel(
         parentEventEmitter.navigateTo(RegistrationRoute.LinkAccount())
       }
       is PhoneNumberEntryScreenEvents.RegisterWithoutNumber -> {
-        parentEventEmitter.navigateTo(RegistrationRoute.SignalLoginPayment)
+        if (state.hasExistingAccount) {
+          parentEventEmitter.navigateTo(RegistrationRoute.SignalLoginCredentialEntry())
+        } else {
+          parentEventEmitter.navigateTo(RegistrationRoute.SignalLoginPayment)
+        }
       }
       is PhoneNumberEntryScreenEvents.CaptchaCompleted -> {
         stateEmitter(applyCaptchaCompleted(state, event.token, parentEventEmitter))

feature/registration/src/main/res/values/strings.xml

@@ -55,6 +55,8 @@
     <string name="RegistrationActivity_next">Next</string>
     <!-- Button on the phone number screen that starts registering with a purchased Signal Login instead of a phone number -->
     <string name="RegistrationActivity_register_without_number">Register without number</string>
+    <!-- Button on the phone number screen, shown when the user already said they have an account to restore, that goes straight to entering their existing Signal Login -->
+    <string name="RegistrationActivity_use_account_id">Use account ID</string>
     <!-- Dialog title to confirm phone number -->
     <string name="RegistrationActivity_is_the_phone_number">Is the phone number below correct?</string>
     <!-- Dialog body to confirm phone number -->

feature/registration/src/test/java/org/signal/registration/RegistrationEndToEndTest.kt

@@ -1840,6 +1840,38 @@ class RegistrationEndToEndTest {
     assert(storageController.restoreDecision == RestoreDecision.SKIPPED) { "Expected SKIPPED restore decision but was ${storageController.restoreDecision}" }
   }
 
+  @Test
+  fun `a pending restore turns the numberless button into a direct jump to signal login entry`() {
+    enableSignalLoginRegistration()
+    val login = signalLoginFor(reregistration = true)
+
+    var registrationComplete = false
+    launchRegistrationFlow(onRegistrationComplete = { registrationComplete = true })
+
+    startManualRestore()
+    chooseRestoreOption(TestTags.ARCHIVE_RESTORE_SELECTION_FROM_SIGNAL_BACKUPS)
+
+    // The user already said they have an account to restore, so the purchase screen is skipped entirely
+    waitForTag(TestTags.PHONE_NUMBER_SCREEN)
+    composeTestRule.onNodeWithTag(TestTags.PHONE_NUMBER_REGISTER_WITHOUT_NUMBER_BUTTON).performClick()
+    waitForTag(TestTags.SIGNAL_LOGIN_CREDENTIAL_ENTRY_SCREEN)
+    assert(composeTestRule.onAllNodesWithTag(TestTags.SIGNAL_LOGIN_PAYMENT_SCREEN).fetchSemanticsNodes().isEmpty()) {
+      "Expected the Signal Login payment screen to be skipped for a user with a pending restore"
+    }
+
+    enterSignalLogin(login)
+
+    chooseRestoreOption(TestTags.ARCHIVE_RESTORE_SELECTION_NONE)
+    waitForTag(Dialogs.TEST_TAG_ALERT_DIALOG_CONFIRM_BUTTON)
+    composeTestRule.onNodeWithTag(Dialogs.TEST_TAG_ALERT_DIALOG_CONFIRM_BUTTON).performClick()
+
+    waitFor("registration to complete") { registrationComplete }
+
+    assert(purchaseApi.launchCount == 0) { "A user with an existing login should never hit Google Play" }
+    assert(networkController.lastCreateSessionE164 == null) { "Expected no verification session for a numberless login" }
+    assert(networkController.lastRegisterAccountRequest?.aci == login.aci) { "Expected the entered login to be reclaimed but was ${networkController.lastRegisterAccountRequest}" }
+  }
+
   @Test
   fun `typing an account id into the phone number field goes straight to signal login entry with it filled in`() {
     enableSignalLoginRegistration()

feature/registration/src/test/java/org/signal/registration/screens/phonenumber/PhoneNumberEntryViewModelTest.kt

@@ -46,6 +46,7 @@ import org.signal.network.api.RegistrationApiV2.SvrCredentials
 import org.signal.network.api.RegistrationApiV2.ThirdPartyServiceErrorResponse
 import org.signal.network.api.RegistrationApiV2.UpdateSessionError
 import org.signal.registration.KeyMaterial
+import org.signal.registration.PendingRestoreOption
 import org.signal.registration.PreExistingRegistrationData
 import org.signal.registration.RegisteredAccountData
 import org.signal.registration.RegistrationFlowEvent
@@ -449,6 +450,38 @@ class PhoneNumberEntryViewModelTest {
       .isInstanceOf<RegistrationRoute.LinkAccount>()
   }
 
+  @Test
+  fun `RegisterWithoutNumber navigates to the Signal Login payment screen`() = runTest {
+    viewModel.applyEvent(
+      PhoneNumberEntryState(),
+      PhoneNumberEntryScreenEvents.RegisterWithoutNumber,
+      parentEventEmitter,
+      stateEmitter
+    )
+
+    assertThat(emittedEvents).hasSize(1)
+    assertThat(emittedEvents.first())
+      .isInstanceOf<RegistrationFlowEvent.NavigateToScreen>()
+      .prop(RegistrationFlowEvent.NavigateToScreen::route)
+      .isInstanceOf<RegistrationRoute.SignalLoginPayment>()
+  }
+
+  @Test
+  fun `RegisterWithoutNumber skips payment and goes straight to credential entry when a restore is pending`() = runTest {
+    viewModel.applyEvent(
+      PhoneNumberEntryState(pendingRestoreOption = PendingRestoreOption.RemoteBackup),
+      PhoneNumberEntryScreenEvents.RegisterWithoutNumber,
+      parentEventEmitter,
+      stateEmitter
+    )
+
+    assertThat(emittedEvents).hasSize(1)
+    assertThat(emittedEvents.first())
+      .isInstanceOf<RegistrationFlowEvent.NavigateToScreen>()
+      .prop(RegistrationFlowEvent.NavigateToScreen::route)
+      .isEqualTo(RegistrationRoute.SignalLoginCredentialEntry())
+  }
+
   @Test
   fun `initial state reflects repository link and sync availability`() = runTest {
     every { mockRepository.isLinkAndSyncAvailable } returns true

feature/registration/src/test/java/org/signal/registration/screens/phonenumber/PhoneNumberScreenTest.kt

@@ -25,6 +25,7 @@ import org.robolectric.RobolectricTestRunner
 import org.robolectric.annotation.Config
 import org.signal.core.ui.CoreUiDependenciesRule
 import org.signal.core.ui.compose.theme.SignalTheme
+import org.signal.registration.PendingRestoreOption
 import org.signal.registration.R
 import org.signal.registration.screens.shared.AccountIdError
 import org.signal.registration.test.TestTags
@@ -326,6 +327,42 @@ class PhoneNumberScreenTest {
     }
   }
 
+  @Test
+  fun `the numberless button offers to register without a number when there is no pending restore`() {
+    // Given
+    composeTestRule.setContent {
+      SignalTheme {
+        PhoneNumberScreen(
+          state = PhoneNumberEntryState(isPhoneNumberlessRegistrationAvailable = true),
+          onEvent = {}
+        )
+      }
+    }
+
+    // Then
+    composeTestRule.onNodeWithText(context.getString(R.string.RegistrationActivity_register_without_number)).assertExists()
+  }
+
+  @Test
+  fun `the numberless button offers to use an account ID when a restore is pending`() {
+    // Given
+    composeTestRule.setContent {
+      SignalTheme {
+        PhoneNumberScreen(
+          state = PhoneNumberEntryState(
+            isPhoneNumberlessRegistrationAvailable = true,
+            pendingRestoreOption = PendingRestoreOption.RemoteBackup
+          ),
+          onEvent = {}
+        )
+      }
+    }
+
+    // Then
+    composeTestRule.onNodeWithText(context.getString(R.string.RegistrationActivity_use_account_id)).assertExists()
+    composeTestRule.onNodeWithText(context.getString(R.string.RegistrationActivity_register_without_number)).assertDoesNotExist()
+  }
+
   private fun accountIdState(accountId: String = "a6b284822e3283d07f2391360a4c2b91") = PhoneNumberEntryState(
     accountId = accountId,
     formattedNumber = accountId,