Store importance as flag

app/src/main/java/eu/faircode/email/AdapterMessage.java

@@ -5263,7 +5263,24 @@ public class AdapterMessage extends RecyclerView.Adapter<AdapterMessage.ViewHold
                         importance = null;
 
                     DB db = DB.getInstance(context);
-                    db.message().setMessageImportance(id, importance);
+                    try {
+                        db.beginTransaction();
+
+                        EntityMessage message = db.message().getMessage(id);
+                        if (message == null)
+                            return null;
+
+                        db.message().setMessageImportance(message.id, importance);
+
+                        EntityOperation.queue(context, message, EntityOperation.KEYWORD,
+                                MessageHelper.FLAG_LOW_IMPORTANCE, EntityMessage.PRIORITIY_LOW.equals(importance));
+                        EntityOperation.queue(context, message, EntityOperation.KEYWORD,
+                                MessageHelper.FLAG_HIGH_IMPORTANCE, EntityMessage.PRIORITIY_HIGH.equals(importance));
+
+                        db.setTransactionSuccessful();
+                    } finally {
+                        db.endTransaction();
+                    }
 
                     return null;
                 }

app/src/main/java/eu/faircode/email/Core.java

@@ -3745,6 +3745,13 @@ class Core {
             message.deliveredto = helper.getDeliveredTo();
             message.thread = helper.getThreadId(context, account.id, folder.id, uid);
             message.priority = helper.getPriority();
+
+            for (String keyword : keywords)
+                if (MessageHelper.FLAG_LOW_IMPORTANCE.equals(keyword))
+                    message.importance = EntityMessage.PRIORITIY_LOW;
+                else if (MessageHelper.FLAG_HIGH_IMPORTANCE.equals(keyword))
+                    message.importance = EntityMessage.PRIORITIY_HIGH;
+
             message.auto_submitted = helper.getAutoSubmitted();
             message.receipt_request = helper.getReceiptRequested();
             message.receipt_to = helper.getReceiptTo();

app/src/main/java/eu/faircode/email/EntityOperation.java

@@ -136,8 +136,11 @@ public class EntityOperation {
 
                 SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context);
                 boolean auto_important = prefs.getBoolean("auto_important", false);
-                if (auto_important)
-                    db.message().setMessageImportance(message.id, flagged ? 2 : null);
+                if (auto_important) {
+                    db.message().setMessageImportance(message.id, flagged ? EntityMessage.PRIORITIY_HIGH : null);
+                    queue(context, message, KEYWORD, MessageHelper.FLAG_LOW_IMPORTANCE, false);
+                    queue(context, message, KEYWORD, MessageHelper.FLAG_HIGH_IMPORTANCE, true);
+                }
 
                 return;
 
@@ -228,8 +231,11 @@ public class EntityOperation {
                             db.message().setMessageUiSeen(similar.id, true);
                         if (autounflag)
                             db.message().setMessageUiFlagged(similar.id, false, null);
-                        if (reset_importance)
+                        if (reset_importance) {
                             db.message().setMessageImportance(similar.id, null);
+                            queue(context, similar, KEYWORD, MessageHelper.FLAG_LOW_IMPORTANCE, false);
+                            queue(context, similar, KEYWORD, MessageHelper.FLAG_HIGH_IMPORTANCE, false);
+                        }
                     }
 
                 if (source.account.equals(target.account)) {

app/src/main/java/eu/faircode/email/EntityRule.java

@@ -918,6 +918,11 @@ public class EntityRule {
         DB db = DB.getInstance(context);
         db.message().setMessageImportance(message.id, importance);
 
+        EntityOperation.queue(context, message, EntityOperation.KEYWORD,
+                MessageHelper.FLAG_LOW_IMPORTANCE, EntityMessage.PRIORITIY_LOW.equals(importance));
+        EntityOperation.queue(context, message, EntityOperation.KEYWORD,
+                MessageHelper.FLAG_HIGH_IMPORTANCE, EntityMessage.PRIORITIY_HIGH.equals(importance));
+
         message.importance = importance;
 
         return true;

app/src/main/java/eu/faircode/email/FragmentMessages.java

@@ -3639,8 +3639,14 @@ public class FragmentMessages extends FragmentBase implements SharedPreferences.
 
                         List<EntityMessage> messages = db.message().getMessagesByThread(
                                 message.account, message.thread, threading ? null : id, message.folder);
-                        for (EntityMessage threaded : messages)
+                        for (EntityMessage threaded : messages) {
                             db.message().setMessageImportance(threaded.id, importance);
+
+                            EntityOperation.queue(context, threaded, EntityOperation.KEYWORD,
+                                    MessageHelper.FLAG_LOW_IMPORTANCE, EntityMessage.PRIORITIY_LOW.equals(importance));
+                            EntityOperation.queue(context, threaded, EntityOperation.KEYWORD,
+                                    MessageHelper.FLAG_HIGH_IMPORTANCE, EntityMessage.PRIORITIY_HIGH.equals(importance));
+                        }
                     }
 
                     db.setTransactionSuccessful();

app/src/main/java/eu/faircode/email/MessageHelper.java

@@ -27,6 +27,7 @@ import android.net.Uri;
 import android.system.ErrnoException;
 import android.text.TextUtils;
 
+import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.core.net.MailTo;
 import androidx.documentfile.provider.DocumentFile;
@@ -167,15 +168,19 @@ public class MessageHelper {
     static final String FLAG_NOT_DELIVERED = "$NotDelivered";
     static final String FLAG_DISPLAYED = "$Displayed";
     static final String FLAG_NOT_DISPLAYED = "$NotDisplayed";
+    static final String FLAG_LOW_IMPORTANCE = "$LowImportance";
+    static final String FLAG_HIGH_IMPORTANCE = "$HighImportance";
 
     // https://www.iana.org/assignments/imap-jmap-keywords/imap-jmap-keywords.xhtml
     // Not black listed: Gmail $Phishing
     private static final List<String> FLAG_BLACKLIST = Collections.unmodifiableList(Arrays.asList(
-            MessageHelper.FLAG_FORWARDED,
-            MessageHelper.FLAG_JUNK,
-            MessageHelper.FLAG_NOT_JUNK,
-            MessageHelper.FLAG_CLASSIFIED, // FairEmail
-            MessageHelper.FLAG_FILTERED, // FairEmail
+            FLAG_FORWARDED,
+            FLAG_JUNK,
+            FLAG_NOT_JUNK,
+            FLAG_CLASSIFIED, // FairEmail
+            FLAG_FILTERED, // FairEmail
+            FLAG_LOW_IMPORTANCE, // FairEmail
+            FLAG_HIGH_IMPORTANCE, // FairEmail
             "$MDNSent", // https://tools.ietf.org/html/rfc3503
             "$SubmitPending",
             "$Submitted",
@@ -1133,6 +1138,7 @@ public class MessageHelper {
         return flags.toString();
     }
 
+    @NonNull
     String[] getKeywords() throws MessagingException {
         List<String> keywords = Arrays.asList(imessage.getFlags().getUserFlags());
         Collections.sort(keywords);