Use the folder index for syncing mails.

If we iterate over all mails, all mails that are not in the current
folder will not be existing in exists(). If we use the index instead to
only get to the mails we need we're in a better situation.

1 files changed, 22 insertions, 3 deletions

diff --git a/examples/maildirresource/maildirresource.cpp b/examples/maildirresource/maildirresource.cpp
index 5a38b01..d0b663b 100644
--- a/examples/maildirresource/maildirresource.cpp
+++ b/examples/maildirresource/maildirresource.cpp
@@ -277,8 +277,27 @@ void MaildirResource::synchronizeMails(Akonadi2::Storage::Transaction &transacti
     Akonadi2::Storage store(Akonadi2::storageLocation(), mResourceInstanceIdentifier + ".synchronization", Akonadi2::Storage::ReadWrite);
     auto synchronizationTransaction = store.createTransaction(Akonadi2::Storage::ReadWrite);
 
-    scanForRemovals(transaction, synchronizationTransaction, bufferType, [&listingPath](const QByteArray &remoteId) -> bool {
-        return QFile(listingPath + QDir::separator() + remoteId).exists();
+    const auto folderLocalId = resolveRemoteId(ENTITY_TYPE_FOLDER, path, synchronizationTransaction);
+
+    auto exists = [&listingPath](const QByteArray &remoteId) -> bool {
+        return QFile(listingPath + "/" + remoteId).exists();
+    };
+
+    auto property = "folder";
+    Index index(bufferType + ".index." + property, transaction);
+    index.lookup(folderLocalId.toLatin1(), [&](const QByteArray &akonadiId) {
+        const auto remoteId = resolveLocalId(bufferType, akonadiId, synchronizationTransaction);
+        if (!remoteId.isEmpty()) {
+            if (!exists(remoteId.toLatin1())) {
+                Trace() << "Found a removed entity: " << akonadiId;
+                deleteEntity(akonadiId, Akonadi2::Storage::maxRevision(transaction), bufferType, [this](const QByteArray &buffer) {
+                    enqueueCommand(mSynchronizerQueue, Akonadi2::Commands::DeleteEntityCommand, buffer);
+                });
+            }
+        }
+    },
+    [property](const Index::Error &error) {
+        Warning() << "Error in index: " <<  error.message << property;
     });
 
     while (entryIterator->hasNext()) {
@@ -300,7 +319,7 @@ void MaildirResource::synchronizeMails(Akonadi2::Storage::Transaction &transacti
         mail.setProperty("sender", msg->from(true)->asUnicodeString());
         mail.setProperty("senderName", msg->from(true)->asUnicodeString());
         mail.setProperty("date", msg->date(true)->dateTime());
-        mail.setProperty("folder", resolveRemoteId(ENTITY_TYPE_FOLDER, path, synchronizationTransaction));
+        mail.setProperty("folder", folderLocalId);
         mail.setProperty("mimeMessage", filepath);
         mail.setProperty("unread", !flags.testFlag(KPIM::Maildir::Seen));
         mail.setProperty("important", flags.testFlag(KPIM::Maildir::Flagged));