Use imported auto-expand folder after refreshing the folder list

app/core/src/main/java/com/fsck/k9/mailstore/AutoExpandFolderBackendFoldersRefreshListener.kt

@@ -4,7 +4,7 @@ import com.fsck.k9.Account
 import com.fsck.k9.Preferences
 
 /**
- * Reset an Account's auto-expand folder when the currently configured folder was removed.
+ * Update an Account's auto-expand folder after the folder list has been refreshed.
  */
 class AutoExpandFolderBackendFoldersRefreshListener(
     private val preferences: Preferences,
@@ -16,14 +16,30 @@ class AutoExpandFolderBackendFoldersRefreshListener(
 
     override fun onAfterFolderListRefresh() {
         checkAutoExpandFolder()
+
+        removeImportedAutoExpandFolder()
+        saveAccount()
     }
 
     private fun checkAutoExpandFolder() {
+        val folderId = account.importedAutoExpandFolder?.let { folderRepository.getFolderId(it) }
+        if (folderId != null) {
+            account.autoExpandFolderId = folderId
+            return
+        }
+
         account.autoExpandFolderId?.let { autoExpandFolderId ->
             if (!folderRepository.isFolderPresent(autoExpandFolderId)) {
                 account.autoExpandFolderId = null
-                preferences.saveAccount(account)
             }
         }
     }
+
+    private fun removeImportedAutoExpandFolder() {
+        account.importedAutoExpandFolder = null
+    }
+
+    private fun saveAccount() {
+        preferences.saveAccount(account)
+    }
 }

app/core/src/main/java/com/fsck/k9/mailstore/FolderRepository.kt

@@ -63,6 +63,23 @@ class FolderRepository(
         }
     }
 
+    fun getFolderId(folderServerId: String): Long? {
+        val database = localStoreProvider.getInstance(account).database
+        return database.execute(false) { db ->
+            db.query(
+                "folders",
+                arrayOf("id"),
+                "server_id = ?",
+                arrayOf(folderServerId),
+                null,
+                null,
+                null
+            ).use { cursor ->
+                if (cursor.moveToFirst()) cursor.getLong(0) else null
+            }
+        }
+    }
+
     fun isFolderPresent(folderId: Long): Boolean {
         val database = localStoreProvider.getInstance(account).database
         return database.execute(false) { db ->