Integrate experimental classifier

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

@@ -1499,6 +1499,7 @@ class Core {
                 parts.isPlainOnly(),
                 HtmlHelper.getPreview(body),
                 parts.getWarnings(message.warning));
+        MessageClassifier.classify(message, true, context);
 
         if (body != null)
             EntityLog.log(context, "Operation body size=" + body.length());
@@ -3002,6 +3003,8 @@ class Core {
                             parts.isPlainOnly(),
                             HtmlHelper.getPreview(body),
                             parts.getWarnings(message.warning));
+                    MessageClassifier.classify(message, true, context);
+
                     if (stats != null && body != null)
                         stats.content += body.length();
                     Log.i(folder.name + " inline downloaded message id=" + message.id +
@@ -3126,10 +3129,10 @@ class Core {
                     db.endTransaction();
                 }
 
-            if (process)
+            if (process) {
                 updateContactInfo(context, folder, message);
-
+                MessageClassifier.classify(message, true, context);
-            else
+            } else
                 Log.d(folder.name + " unchanged uid=" + uid);
         }
 
@@ -3430,6 +3433,8 @@ class Core {
                             parts.isPlainOnly(),
                             HtmlHelper.getPreview(body),
                             parts.getWarnings(message.warning));
+                    MessageClassifier.classify(message, true, context);
+
                     if (stats != null && body != null)
                         stats.content += body.length();
                     Log.i(folder.name + " downloaded message id=" + message.id +

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

@@ -229,6 +229,9 @@ public class EntityOperation {
                             db.rule().deleteRule(rule.id);
                 }
 
+                if (message.content)
+                    MessageClassifier.classify(message, false, context);
+
                 // Create copy without uid in target folder
                 // Message with same msgid can be in archive
                 if (message.uid != null &&

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

@@ -20,8 +20,11 @@ package eu.faircode.email;
 */
 
 import android.content.Context;
+import android.content.SharedPreferences;
 import android.text.TextUtils;
 
+import androidx.preference.PreferenceManager;
+
 import org.jetbrains.annotations.NotNull;
 
 import java.io.File;
@@ -42,10 +45,11 @@ public class MessageClassifier {
     private static final double CHANCE_THRESHOLD = 2.0;
 
     static String classify(EntityMessage message, boolean added, Context context) {
-        DB db = DB.getInstance(context);
+        SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context);
+        if (!prefs.getBoolean("classify", BuildConfig.DEBUG))
+            return null;
 
-        if (!message.content)
+        DB db = DB.getInstance(context);
-            throw new IllegalArgumentException("Message without content");
 
         EntityFolder folder = db.folder().getFolder(message.folder);
         if (folder == null)
@@ -80,14 +84,15 @@ public class MessageClassifier {
             m = (m == null ? 1 : m + 1);
             classMessages.put(folder.name, m);
         } else {
-            if (m != null)
+            if (m != null && m > 0)
                 classMessages.put(folder.name, m - 1);
         }
+        Log.i("Classifier classify=" + folder.name + " messages=" + classMessages.get(folder.name));
 
         return classified;
     }
 
-    static String classify(String classify, String text, boolean added) {
+    private static String classify(String classify, String text, boolean added) {
         int maxFrequency = 0;
         int maxMatchedWords = 0;
         List<String> words = new ArrayList<>();
@@ -107,7 +112,10 @@ public class MessageClassifier {
                 if (!added) {
                     Integer c = (classFrequency == null ? null : classFrequency.get(classify));
                     if (c != null)
-                        classFrequency.put(classify, c - 1);
+                        if (c > 0)
+                            classFrequency.put(classify, c - 1);
+                        else
+                            classFrequency.remove(classify);
                     continue;
                 }
 

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

@@ -42,7 +42,7 @@ import io.requery.android.database.sqlite.SQLiteDatabase;
 import static android.os.Process.THREAD_PRIORITY_BACKGROUND;
 
 public class WorkerFts extends Worker {
-    private static final int INDEX_DELAY = BuildConfig.DEBUG ? 3 : 30; // seconds
+    private static final int INDEX_DELAY = 30; // seconds
     private static final int INDEX_BATCH_SIZE = 100;
 
     public WorkerFts(@NonNull Context context, @NonNull WorkerParameters workerParams) {
@@ -78,9 +78,6 @@ public class WorkerFts extends Worker {
                             continue;
                         }
 
-                        if (BuildConfig.DEBUG)
-                            MessageClassifier.classify(message, true, context);
-
                         File file = message.getFile(context);
                         String text = HtmlHelper.getFullText(file);
                         if (TextUtils.isEmpty(text)) {