Prevent blocking common domain names

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

@@ -99,6 +99,22 @@ public class EmailProvider {
             throw new UnknownHostException(this.name + " invalid");
     }
 
+    static List<String> getDomainNames(Context context) {
+        List<String> result = new ArrayList<>();
+
+        for (String domain : PROPRIETARY)
+            result.add(domain.replace(".", "\\."));
+
+        List<EmailProvider> providers = loadProfiles(context);
+        for (EmailProvider provider : providers)
+            if (provider.domain != null)
+                for (String domain : provider.domain)
+                    if (!result.contains(domain))
+                        result.add(domain);
+
+        return result;
+    }
+
     static List<EmailProvider> loadProfiles(Context context) {
         List<EmailProvider> result = null;
         try {

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

@@ -540,14 +540,23 @@ public class EntityRule {
         return cal;
     }
 
-    static EntityRule blockSender(Context context, EntityMessage message, EntityFolder junk, boolean block_domain) throws JSONException {
+    static EntityRule blockSender(Context context, EntityMessage message, EntityFolder junk, boolean block_domain, List<String> whitelist) throws JSONException {
         String sender = ((InternetAddress) message.from[0]).getAddress();
         String name = MessageHelper.formatAddresses(new Address[]{message.from[0]});
 
         if (block_domain) {
             int at = sender.indexOf('@');
-            if (at > 0)
-                sender = sender.substring(at);
+            if (at > 0) {
+                boolean whitelisted = false;
+                String domain = sender.substring(at + 1);
+                for (String d : whitelist)
+                    if (domain.matches(d)) {
+                        whitelisted = true;
+                        break;
+                    }
+                if (!whitelisted)
+                    sender = '@' + domain;
+            }
         }
 
         JSONObject jsender = new JSONObject();

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

@@ -6036,6 +6036,7 @@ public class FragmentMessages extends FragmentBase implements SharedPreferences.
                 long id = args.getLong("id");
                 boolean block_sender = args.getBoolean("block_sender");
                 boolean block_domain = args.getBoolean("block_domain");
+                List<String> whitelist = EmailProvider.getDomainNames(context);
 
                 DB db = DB.getInstance(context);
                 try {
@@ -6053,7 +6054,7 @@ public class FragmentMessages extends FragmentBase implements SharedPreferences.
 
                     if ((block_sender || block_domain) &&
                             (message.from != null && message.from.length > 0)) {
-                        EntityRule rule = EntityRule.blockSender(context, message, junk, block_sender);
+                        EntityRule rule = EntityRule.blockSender(context, message, junk, block_sender, whitelist);
                         rule.id = db.rule().insertRule(rule);
                     }
 

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

@@ -240,6 +240,7 @@ public class ServiceUI extends IntentService {
     private void onJunk(long id) throws JSONException {
         SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this);
         boolean block_sender = prefs.getBoolean("notify_block_sender", false);
+        List<String> whitelist = EmailProvider.getDomainNames(this);
 
         DB db = DB.getInstance(this);
         try {
@@ -256,7 +257,7 @@ public class ServiceUI extends IntentService {
             EntityOperation.queue(this, message, EntityOperation.MOVE, junk.id);
 
             if (block_sender) {
-                EntityRule rule = EntityRule.blockSender(this, message, junk, false);
+                EntityRule rule = EntityRule.blockSender(this, message, junk, false, whitelist);
                 rule.id = db.rule().insertRule(rule);
             }