From dd95e168814a0cd61ae0bb0e59ae65981cf54710 Mon Sep 17 00:00:00 2001
From: Andreas Troelsen <garbagemule@gmail.com>
Date: Fri, 4 May 2018 03:52:07 +0200
Subject: [PATCH] Refactor entry fee logic.

This commit swaps out the naive call to takeFee with a more robust approach that actually checks the result. If it fails, the player doesn't join.

It also refactors takeFee so that it will refund any already taken parts of the entry fee if one of the parts fails.
---
 .../com/garbagemule/MobArena/ArenaImpl.java   | 24 ++++++++++++++-----
 1 file changed, 18 insertions(+), 6 deletions(-)

diff --git a/src/main/java/com/garbagemule/MobArena/ArenaImpl.java b/src/main/java/com/garbagemule/MobArena/ArenaImpl.java
index 8301b8c..39771da 100644
--- a/src/main/java/com/garbagemule/MobArena/ArenaImpl.java
+++ b/src/main/java/com/garbagemule/MobArena/ArenaImpl.java
@@ -49,9 +49,11 @@ import org.bukkit.inventory.PlayerInventory;
 import org.bukkit.permissions.PermissionAttachment;
 import org.bukkit.potion.PotionEffect;
 
+import java.util.ArrayDeque;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
+import java.util.Deque;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.LinkedList;
@@ -668,7 +670,13 @@ public class ArenaImpl implements Arena
 
         specPlayers.remove(p);
 
-        takeFee(p);
+        if (!entryFee.isEmpty()) {
+            if (!takeFee(p)) {
+                messenger.tell(p, Msg.JOIN_FEE_REQUIRED, MAUtils.listToString(entryFee, plugin));
+                return false;
+            }
+            messenger.tell(p, Msg.JOIN_FEE_PAID.format(MAUtils.listToString(entryFee, plugin)));
+        }
 
         // Announce globally (must happen before moving player)
         if (settings.getBoolean("global-join-announce", false)) {
@@ -1498,13 +1506,17 @@ public class ArenaImpl implements Arena
 
     @Override
     public boolean takeFee(Player p) {
-        if (entryFee.isEmpty()) return true;
-
+        Deque<Thing> paid = new ArrayDeque<>();
         for (Thing fee : entryFee) {
-            fee.takeFrom(p);
+            if (fee.takeFrom(p)) {
+                paid.push(fee);
+            } else {
+                while (!paid.isEmpty()) {
+                    paid.pop().giveTo(p);
+                }
+                return false;
+            }
         }
-
-        messenger.tell(p, Msg.JOIN_FEE_PAID.format(MAUtils.listToString(entryFee, plugin)));
         return true;
     }