1.2.1: clearer Google sign-in failures on microG

- show the ApiException status code (e.g. DEVELOPER_ERROR 10) instead of
  silently falling back to the browser
- do not leave the app when the picker is cancelled (12501/16)
- report a missing ID token explicitly (Android OAuth client / SHA-1 hint)
- version 1.2.1

app/build.gradle.kts

@@ -22,8 +22,8 @@ android {
         applicationId = "dev.n1ko.nikogpt"
         minSdk = 29 // Android 10
         targetSdk = 35
-        versionCode = 6
-        versionName = "1.2.0"
+        versionCode = 7
+        versionName = "1.2.1"
     }
 
     signingConfigs {

app/src/main/java/dev/n1ko/nikogpt/MainActivity.kt

@@ -95,16 +95,28 @@ class MainActivity : AppCompatActivity() {
     private val legacySignIn: ActivityResultLauncher<Intent> =
         registerForActivityResult(ActivityResultContracts.StartActivityForResult()) { result ->
             val link = legacyLinkMode
-            try {
-                val account = GoogleSignIn.getSignedInAccountFromIntent(result.data)
+            val account = try {
+                GoogleSignIn.getSignedInAccountFromIntent(result.data)
                     .getResult(ApiException::class.java)
-                val token = account?.idToken
-                if (!token.isNullOrBlank()) deliverToken(token, link) else openGoogleInBrowser(link)
             } catch (e: ApiException) {
+                // 12501/16 = the user closed the picker: stay in the app.
+                if (e.statusCode == 12501 || e.statusCode == 16) return@registerForActivityResult
+                Toast.makeText(this, getString(R.string.google_error_code, e.statusCode), Toast.LENGTH_LONG).show()
                 openGoogleInBrowser(link)
+                return@registerForActivityResult
             } catch (e: Exception) {
                 openGoogleInBrowser(link)
+                return@registerForActivityResult
             }
+            val token = account?.idToken
+            if (token.isNullOrBlank()) {
+                // microG accepted the account but could not mint an ID token
+                // (e.g. device registration is off): say so, then fall back.
+                Toast.makeText(this, getString(R.string.google_no_token), Toast.LENGTH_LONG).show()
+                openGoogleInBrowser(link)
+                return@registerForActivityResult
+            }
+            deliverToken(token, link)
         }
 
     // Runtime microphone permission, bridged to the WebView.

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

@@ -7,6 +7,8 @@
     <string name="download_started">Загрузка началась</string>
     <string name="download_failed">Не удалось начать загрузку</string>
     <string name="google_error">Не удалось войти через Google (%1$s)</string>
+    <string name="google_error_code">Не удалось войти через Google (код %1$d)</string>
+    <string name="google_no_token">Google не вернул ID-токен (проверьте Android OAuth-клиент: package и SHA-1)</string>
     <string name="attach_file">Файл</string>
     <string name="attach_camera">Камера</string>
 </resources>

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

@@ -7,6 +7,8 @@
     <string name="download_started">Download started</string>
     <string name="download_failed">Could not start the download</string>
     <string name="google_error">Google sign-in failed (%1$s)</string>
+    <string name="google_error_code">Google sign-in failed (code %1$d)</string>
+    <string name="google_no_token">Google did not return an ID token (check the Android OAuth client, package and SHA-1)</string>
     <string name="attach_file">File</string>
     <string name="attach_camera">Camera</string>
 </resources>