Merge pull request #173 from KAMKEEL/codex/fix-profile-saving-and-slot-id-issues

Fix profile login save and clarify async behavior

src/main/java/kamkeel/npcs/controllers/ProfileController.java

@@ -97,6 +97,7 @@ public class ProfileController implements IProfileHandler {
         if (player == null)
             return;
         Profile profile;
+        boolean profileModified = false;
         if (activeProfiles.containsKey(player.getUniqueID())) {
             profile = activeProfiles.get(player.getUniqueID());
             profile.player = player;
@@ -109,6 +110,7 @@ public class ProfileController implements IProfileHandler {
                 profile.getSlots().put(0, defaultSlot);
                 profile.currentSlotId = 0;
                 saveSlotData(player);
+                profileModified = true;
             }
             if (!profile.getSlots().containsKey(profile.currentSlotId)) {
                 profile.currentSlotId = 0;
@@ -117,7 +119,10 @@ public class ProfileController implements IProfileHandler {
             activeProfiles.put(player.getUniqueID(), profile);
             loadSlotData(player);
             verifySlotQuests(profile.player);
-            save(player, profile);
+            // Avoid saving on every login; only persist if the profile was
+            // modified (e.g. default slot creation).
+            if (profileModified)
+                save(player, profile);
         }
     }
 
@@ -341,6 +346,7 @@ public class ProfileController implements IProfileHandler {
             return ProfileOperation.error(MSG_CANNOT_CLONE_CURRENT);
         }
         if (temporary) {
+            // Use a negative ID for temporary slots so they are never saved to disk.
             destinationSlotId = getNextAvailableTempSlot(profile);
         } else {
             if (destinationSlotId <= 0) {

src/main/java/kamkeel/npcs/controllers/data/profile/Profile.java

@@ -81,7 +81,8 @@ public class Profile implements IProfile {
         compound.setInteger("CurrentSlotId", currentSlotId);
         NBTTagCompound slotsCompound = new NBTTagCompound();
         for (Map.Entry<Integer, ISlot> entry : slots.entrySet()) {
-            // Save only non-temporary slots.
+            // Temporary slots (typically using negative IDs) are kept in memory
+            // only and skipped here so they never persist to disk.
             if (entry.getValue().isTemporary())
                 continue;
             slotsCompound.setTag(String.valueOf(entry.getKey()), entry.getValue().toNBT());

src/main/java/noppes/npcs/util/CustomNPCsThreader.java

@@ -4,5 +4,10 @@ import java.util.concurrent.Executor;
 import java.util.concurrent.Executors;
 
 public class CustomNPCsThreader {
+    /**
+     * Executor used for all asynchronous profile and player data saves.
+     * It is single-threaded so submitted tasks run sequentially and the
+     * save order for a given player is preserved.
+     */
     public static final Executor customNPCThread = Executors.newSingleThreadExecutor();
 }