Store attachment count for better performance

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

@@ -3159,6 +3159,10 @@ public class AdapterMessage extends RecyclerView.Adapter<AdapterMessage.ViewHold
                         same = false;
                         Log.i("size changed id=" + next.id);
                     }
+                    if (!Objects.equals(prev.attachments, next.attachments)) {
+                        same = false;
+                        Log.i("attachments changed id=" + next.id);
+                    }
                     if (!prev.content.equals(next.content)) {
                         same = false;
                         Log.i("content changed id=" + next.id);

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

@@ -57,7 +57,7 @@ import io.requery.android.database.sqlite.RequerySQLiteOpenHelperFactory;
 // https://developer.android.com/topic/libraries/architecture/room.html
 
 @Database(
-        version = 95,
+        version = 96,
         entities = {
                 EntityIdentity.class,
                 EntityAccount.class,
@@ -161,7 +161,19 @@ public abstract class DB extends RoomDatabase {
                 .databaseBuilder(context, DB.class, DB_NAME)
                 .openHelperFactory(new RequerySQLiteOpenHelperFactory())
                 .setQueryExecutor(executor)
-                .setJournalMode(JournalMode.WRITE_AHEAD_LOGGING);
+                .setJournalMode(JournalMode.WRITE_AHEAD_LOGGING)
+                .addCallback(new Callback() {
+                    @Override
+                    public void onOpen(@NonNull SupportSQLiteDatabase db) {
+                        Log.i("Creating triggers");
+                        db.execSQL("CREATE TRIGGER IF NOT EXISTS attachment_insert" +
+                                " AFTER INSERT ON attachment" +
+                                " BEGIN UPDATE message SET attachments = attachments + 1 WHERE message.id = NEW.message; END");
+                        db.execSQL("CREATE TRIGGER IF NOT EXISTS attachment_delete" +
+                                " AFTER DELETE ON attachment" +
+                                " BEGIN UPDATE message SET attachments = attachments - 1 WHERE message.id = OLD.message; END");
+                    }
+                });
     }
 
     private static DB migrate(final Context context, RoomDatabase.Builder<DB> builder) {
@@ -956,6 +968,15 @@ public abstract class DB extends RoomDatabase {
                         db.execSQL("ALTER TABLE `identity` ADD COLUMN `sign_key` INTEGER");
                     }
                 })
+                .addMigrations(new Migration(95, 96) {
+                    @Override
+                    public void migrate(@NonNull SupportSQLiteDatabase db) {
+                        Log.i("DB migration from version " + startVersion + " to " + endVersion);
+                        db.execSQL("ALTER TABLE `message` ADD COLUMN `attachments` INTEGER NOT NULL DEFAULT 0");
+                        db.execSQL("UPDATE message SET attachments =" +
+                                " (SELECT COUNT(attachment.id) FROM attachment WHERE attachment.message = message.id)");
+                    }
+                })
                 .build();
     }
 

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

@@ -50,7 +50,6 @@ public interface DaoMessage {
             ", COUNT(message.id) AS count" +
             ", " + unseen_unified + " AS unseen" +
             ", " + unflagged_unified + " AS unflagged" +
-            ", (SELECT COUNT(a.id) FROM attachment a WHERE a.message = message.id) AS attachments" +
             ", SUM(CASE WHEN folder.type = '" + EntityFolder.DRAFTS + "' THEN 1 ELSE 0 END) AS drafts" +
             ", COUNT(DISTINCT CASE WHEN message.msgid IS NULL THEN message.id ELSE message.msgid END) AS visible" +
             ", SUM(message.size) AS totalSize" +
@@ -99,7 +98,6 @@ public interface DaoMessage {
             ", COUNT(message.id) AS count" +
             ", " + unseen_folder + " AS unseen" +
             ", " + unflagged_folder + " AS unflagged" +
-            ", (SELECT COUNT(a.id) FROM attachment a WHERE a.message = message.id) AS attachments" +
             ", SUM(CASE WHEN folder.type = '" + EntityFolder.DRAFTS + "' THEN 1 ELSE 0 END) AS drafts" +
             ", COUNT(DISTINCT CASE WHEN message.msgid IS NULL THEN message.id ELSE message.msgid END) AS visible" +
             ", SUM(message.size) AS totalSize" +
@@ -142,7 +140,6 @@ public interface DaoMessage {
             ", 1 AS count" +
             ", CASE WHEN message.ui_seen THEN 0 ELSE 1 END AS unseen" +
             ", CASE WHEN message.ui_flagged THEN 0 ELSE 1 END AS unflagged" +
-            ", (SELECT COUNT(a.id) FROM attachment a WHERE a.message = message.id) AS attachments" +
             ", CASE WHEN folder.type = '" + EntityFolder.DRAFTS + "' THEN 1 ELSE 0 END AS drafts" +
             ", 1 AS visible" +
             ", message.size AS totalSize" +
@@ -250,7 +247,6 @@ public interface DaoMessage {
             ", 1 AS count" +
             ", CASE WHEN message.ui_seen THEN 0 ELSE 1 END AS unseen" +
             ", CASE WHEN message.ui_flagged THEN 0 ELSE 1 END AS unflagged" +
-            ", (SELECT COUNT(a.id) FROM attachment a WHERE a.message = message.id) AS attachments" +
             ", CASE WHEN folder.type = '" + EntityFolder.DRAFTS + "' THEN 1 ELSE 0 END AS drafts" +
             ", 1 AS visible" +
             ", message.size AS totalSize" +
@@ -268,7 +264,6 @@ public interface DaoMessage {
             ", 1 AS count" +
             ", 1 AS unseen" +
             ", 0 AS unflagged" +
-            ", 0 AS attachments" +
             ", 0 AS drafts" +
             ", 1 AS visible" +
             ", message.size AS totalSize" +

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

@@ -113,6 +113,8 @@ public class EntityMessage implements Serializable {
     public String subject;
     public Long size;
     @NonNull
+    public Integer attachments = 0; // performance
+    @NonNull
     public Boolean content = false;
     public Boolean plain_only = null;
     public Boolean encrypt = null;
@@ -266,6 +268,7 @@ public class EntityMessage implements Serializable {
                     Objects.equals(this.raw, other.raw) &&
                     Objects.equals(this.subject, other.subject) &&
                     Objects.equals(this.size, other.size) &&
+                    Objects.equals(this.attachments, other.attachments) &&
                     this.content == other.content &&
                     Objects.equals(this.plain_only, other.plain_only) &&
                     Objects.equals(this.preview, other.preview) &&

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

@@ -37,7 +37,6 @@ public class TupleMessageEx extends EntityMessage {
     public int count;
     public int unseen;
     public int unflagged;
-    public int attachments;
     public int drafts;
     public int visible;
     public Long totalSize;
@@ -63,7 +62,6 @@ public class TupleMessageEx extends EntityMessage {
                     this.count == other.count &&
                     this.unseen == other.unseen &&
                     this.unflagged == other.unflagged &&
-                    this.attachments == other.attachments &&
                     this.drafts == other.drafts &&
                     this.visible == other.visible &&
                     Objects.equals(this.totalSize, other.totalSize) &&