Properly update MLM sack values on login/logout (#6627)

- Prevent unnecessary code execution while logged out
- Fix inventory size on initial login
- Refresh sack values on initial login

runelite-client/src/main/java/net/runelite/client/plugins/motherlode/MotherlodePlugin.java

@@ -87,6 +87,8 @@ public class MotherlodePlugin extends Plugin
 			ItemID.MITHRIL_ORE, ItemID.GOLD_ORE, ItemID.COAL, ItemID.GOLDEN_NUGGET);
 	private static final Set<Integer> ROCK_OBSTACLES = ImmutableSet.of(ROCKFALL, ROCKFALL_26680);
 
+	private static final int MAX_INVENTORY_SIZE = 28;
+
 	private static final int SACK_LARGE_SIZE = 162;
 	private static final int SACK_SIZE = 81;
 
@@ -359,13 +361,18 @@ public class MotherlodePlugin extends Plugin
 		{
 			inMlm = checkInMlm();
 		}
+		else if (event.getGameState() == GameState.LOGIN_SCREEN)
+		{
+			// Prevent code from running while logged out.
+			inMlm = false;
+		}
 	}
 
 	private Integer calculateDepositsLeft()
 	{
 		if (maxSackSize == 0) // check if maxSackSize has been initialized
 		{
-			return null;
+			refreshSackValues();
 		}
 
 		double depositsLeft = 0;
@@ -380,8 +387,6 @@ public class MotherlodePlugin extends Plugin
 		Item[] result = inventory.getItems();
 		assert result != null;
 
-		int inventorySize = result.length;
-
 		for (Item item : result)
 		{
 			// Assume that MLM ores are being banked and exclude them from the check,
@@ -394,7 +399,7 @@ public class MotherlodePlugin extends Plugin
 			}
 		}
 
-		double inventorySpace = inventorySize - nonPayDirtItems;
+		double inventorySpace = MAX_INVENTORY_SIZE - nonPayDirtItems;
 		double sackSizeRemaining = maxSackSize - curSackSize;
 
 		if (inventorySpace > 0 && sackSizeRemaining > 0)