Implement Gmail's XLIST IMAP command to determine Gmail-specific folders.

src/com/fsck/k9/activity/setup/AccountSetupBasics.java

@@ -193,16 +193,9 @@ public class AccountSetupBasics extends K9Activity
             incomingUsername = incomingUsername.replaceAll("\\$domain", domain);
 
             URI incomingUriTemplate = mProvider.incomingUriTemplate;
-
-            String namespace = null;
-            // Gmail uses a special namespace, otherwise everything ends up in the "[Imap]" namespace.
-            if(incomingUriTemplate.getHost().toLowerCase().endsWith("gmail.com")) {
-                namespace = "/[Gmail]";
-            }
-
             incomingUri = new URI(incomingUriTemplate.getScheme(), incomingUsername + ":"
-                + passwordEnc, incomingUriTemplate.getHost(), incomingUriTemplate.getPort(),
-                namespace, null, null);
+                                  + passwordEnc, incomingUriTemplate.getHost(), incomingUriTemplate.getPort(), null,
+                                  null, null);
 
             String outgoingUsername = mProvider.outgoingUsernameTemplate;
 
@@ -233,7 +226,7 @@ public class AccountSetupBasics extends K9Activity
             mAccount.setTrashFolderName(getString(R.string.special_mailbox_name_trash));
             mAccount.setArchiveFolderName(getString(R.string.special_mailbox_name_archive));
             // Yahoo! has a special folder for Spam, called "Bulk Mail".
-            if (incomingUriTemplate.getHost().toLowerCase().endsWith("yahoo.com")) {
+            if (incomingUriTemplate.getHost().toLowerCase().endsWith(".yahoo.com")) {
                 mAccount.setSpamFolderName("Bulk Mail");
             } else {
                 mAccount.setSpamFolderName(getString(R.string.special_mailbox_name_spam));

src/com/fsck/k9/mail/store/ImapStore.java

@@ -596,11 +596,75 @@ public class ImapStore extends Store {
 
     }
 
+    /**
+     * Attempt to auto-configure Gmail folders, if we think the server is a Gmail server.
+     *
+     * The parsing here is essentially the same as
+     * {@link #listFolders(com.fsck.k9.mail.store.ImapStore.ImapConnection, boolean)}; we should try to consolidate
+     * this at some point. :(
+     * @param connection IMAP Connection
+     * @throws IOException uh oh!
+     * @throws MessagingException uh oh!
+     */
+    private void configureGmailFolders(final ImapConnection connection) throws IOException, MessagingException {
+        final String commandResponse = "XLIST";
+
+        if (!connection.mSettings.getHost().toLowerCase().endsWith(".gmail.com") || !connection.capabilities.contains(commandResponse)) {
+            if (K9.DEBUG) {
+                Log.d(K9.LOG_TAG, "Probably not a Gmail server, skipping Gmail namespace detection.");
+            }
+            return;
+        }
+
+        final List<ImapResponse> responses =
+            connection.executeSimpleCommand(String.format("%s \"\" %s", commandResponse,
+                encodeString(getCombinedPrefix() + "*")));
+
+        for (ImapResponse response : responses) {
+            if (ImapResponseParser.equalsIgnoreCase(response.get(0), commandResponse)) {
+
+                String decodedFolderName;
+                try {
+                    decodedFolderName = decodeFolderName(response.getString(3));
+                } catch (CharacterCodingException e) {
+                    Log.w(K9.LOG_TAG, "Folder name not correctly encoded with the UTF-7 variant " +
+                        "as defined by RFC 3501: " + response.getString(3), e);
+                    // We currently just skip folders with malformed names.
+                    continue;
+                }
+
+                if (mPathDelimeter == null) {
+                    mPathDelimeter = response.getString(2);
+                    mCombinedPrefix = null;
+                }
+
+                ImapList attributes = response.getList(1);
+                for (int i = 0, count = attributes.size(); i < count; i++) {
+                    String attribute = attributes.getString(i);
+                    if (attribute.equals("\\Drafts")) {
+                        mAccount.setDraftsFolderName(decodedFolderName);
+                        if (K9.DEBUG) Log.d(K9.LOG_TAG, "Detected Gmail draft folder: " + decodedFolderName);
+                    } else if (attribute.equals("\\Sent")) {
+                        mAccount.setSentFolderName(decodedFolderName);
+                        if (K9.DEBUG) Log.d(K9.LOG_TAG, "Detected Gmail sent folder: " + decodedFolderName);
+                    } else if (attribute.equals("\\Spam")) {
+                        mAccount.setSpamFolderName(decodedFolderName);
+                        if (K9.DEBUG) Log.d(K9.LOG_TAG, "Detected Gmail spam folder: " + decodedFolderName);
+                    } else if (attribute.equals("\\Trash")) {
+                        mAccount.setTrashFolderName(decodedFolderName);
+                        if (K9.DEBUG) Log.d(K9.LOG_TAG, "Detected Gmail trash folder: " + decodedFolderName);
+                    }
+                }
+            }
+        }
+    }
+
     @Override
     public void checkSettings() throws MessagingException {
         try {
             ImapConnection connection = new ImapConnection(new StoreImapSettings());
             connection.open();
+            configureGmailFolders(connection);
             connection.close();
         } catch (IOException ioe) {
             throw new MessagingException(K9.app.getString(R.string.error_unable_to_connect), ioe);