feat: remove gmail prefix in folder structure

Author: shamim-emon

legacy/storage/src/main/java/com/fsck/k9/storage/messages/CreateFolderOperations.kt

@@ -11,7 +11,7 @@ internal class CreateFolderOperations(private val lockableDatabase: LockableData
             for (folder in folders) {
                 val folderSettings = folder.settings
                 val values = ContentValues().apply {
-                    put("name", folder.name)
+                    put("name", folder.name.replace("\\[(Gmail|Google Mail)]/".toRegex(), ""))
                     put("visible_limit", folderSettings.visibleLimit)
                     put("integrate", folderSettings.integrate)
                     put("top_group", folderSettings.inTopGroup)

legacy/storage/src/main/java/com/fsck/k9/storage/messages/FolderNameSanitizer.kt

@@ -0,0 +1,36 @@
+package com.fsck.k9.storage.messages
+
+import android.content.ContentValues
+import com.fsck.k9.mailstore.LockableDatabase
+
+internal class FolderNameSanitizer(private val lockableDatabase: LockableDatabase) {
+    fun removeGmailPrefixFromFolders() {
+        lockableDatabase.execute(false) { db ->
+            val cursor = db.query(
+                "folders",
+                arrayOf("id", "name"),
+                "name LIKE ? OR name LIKE ?",
+                arrayOf("%[Gmail]/%", "%[Google Mail]/%"),
+                null,
+                null,
+                null,
+            )
+
+            while (cursor.moveToNext()) {
+                val id = cursor.getLong(cursor.getColumnIndexOrThrow("id"))
+                val name = cursor.getString(cursor.getColumnIndexOrThrow("name"))
+                val updatedName = name
+                    .replace("[Gmail]/", "")
+                    .replace("[Google Mail]/", "")
+
+                val values = ContentValues().apply {
+                    put("name", updatedName)
+                }
+
+                db.update("folders", values, "id = ?", arrayOf(id.toString()))
+            }
+
+            cursor.close()
+        }
+    }
+}

legacy/storage/src/main/java/com/fsck/k9/storage/messages/K9MessageStoreFactory.kt

@@ -13,8 +13,18 @@ class K9MessageStoreFactory(
     private val storageFilesProviderFactory: StorageFilesProviderFactory,
     private val basicPartInfoExtractor: BasicPartInfoExtractor,
 ) : MessageStoreFactory {
+    private lateinit var folderNameSanitizer: FolderNameSanitizer
+
     override fun create(account: LegacyAccount): ListenableMessageStore {
         val localStore = localStoreProvider.getInstance(account)
+        if (account.incomingServerSettings.host.contains("gmail") ||
+            account.incomingServerSettings.host.contains("gmail")
+        ) {
+            if (!this::folderNameSanitizer.isInitialized) {
+                folderNameSanitizer = FolderNameSanitizer(lockableDatabase = localStore.database)
+            }
+            folderNameSanitizer.removeGmailPrefixFromFolders()
+        }
         val storageFilesProvider = storageFilesProviderFactory.createStorageFilesProvider(account.uuid)
         val messageStore = K9MessageStore(
             localStore.database,