From 55da3e4092845eb29c76b7fe4ca3fb93e1bbbb5a Mon Sep 17 00:00:00 2001
From: ohnoey <cccm5dev@gmail.com>
Date: Sun, 11 Aug 2024 09:27:38 -0700
Subject: [PATCH] Return prior value from set

---
 .../java/net/countercraft/movecraft/craft/BaseCraft.java | 4 ++--
 .../java/net/countercraft/movecraft/craft/Craft.java     | 2 +-
 .../movecraft/craft/datatag/CraftDataTagContainer.java   | 9 +++++++--
 3 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/Movecraft/src/main/java/net/countercraft/movecraft/craft/BaseCraft.java b/Movecraft/src/main/java/net/countercraft/movecraft/craft/BaseCraft.java
index 3a687e8f1..9fc542f89 100644
--- a/Movecraft/src/main/java/net/countercraft/movecraft/craft/BaseCraft.java
+++ b/Movecraft/src/main/java/net/countercraft/movecraft/craft/BaseCraft.java
@@ -551,8 +551,8 @@ public void setAudience(@NotNull Audience audience) {
     }
 
     @Override
-    public <T> void setDataTag(final @NotNull CraftDataTagKey<T> tagKey, final T data) {
-        dataTagContainer.set(tagKey, data);
+    public <T> T setDataTag(final @NotNull CraftDataTagKey<T> tagKey, final T data) {
+        return dataTagContainer.set(tagKey, data);
     }
 
     @Override
diff --git a/api/src/main/java/net/countercraft/movecraft/craft/Craft.java b/api/src/main/java/net/countercraft/movecraft/craft/Craft.java
index c7db251dc..deaad0c72 100644
--- a/api/src/main/java/net/countercraft/movecraft/craft/Craft.java
+++ b/api/src/main/java/net/countercraft/movecraft/craft/Craft.java
@@ -274,7 +274,7 @@ default void setLastDZ(int dZ){}
 
     void setAudience(Audience audience);
 
-    <T> void setDataTag(@NotNull final CraftDataTagKey<T> tagKey, final T data);
+    <T> T setDataTag(@NotNull final CraftDataTagKey<T> tagKey, final T data);
 
     <T> T getDataTag(@NotNull final CraftDataTagKey<T> tagKey);
 
diff --git a/api/src/main/java/net/countercraft/movecraft/craft/datatag/CraftDataTagContainer.java b/api/src/main/java/net/countercraft/movecraft/craft/datatag/CraftDataTagContainer.java
index 32f934827..4eee17a55 100644
--- a/api/src/main/java/net/countercraft/movecraft/craft/datatag/CraftDataTagContainer.java
+++ b/api/src/main/java/net/countercraft/movecraft/craft/datatag/CraftDataTagContainer.java
@@ -47,12 +47,17 @@ public <T> T get(final @NotNull Craft craft, final @NotNull CraftDataTagKey<T> t
      * @param value the value to set for future lookups
      * @param <T> the type of the value
      */
-    public <T> void set(final @NotNull CraftDataTagKey<T> tagKey, final @NotNull T value) {
+    public <T> @Nullable T set(final @NotNull CraftDataTagKey<T> tagKey, final @NotNull T value) {
         if (!CraftDataTagRegistry.INSTANCE.isRegistered(tagKey.key)) {
             throw new IllegalArgumentException(String.format("The provided key %s was not registered.", tagKey));
         }
+        try {
+            //noinspection unchecked
+            return (T) backing.put(tagKey, value);
+        } catch (ClassCastException cce) {
+            throw new IllegalStateException(String.format("The provided key %s has an invalid value type.", tagKey), cce);
+        }
 
-        backing.put(tagKey, value);
     }
 
     public <T> T compute(final @NotNull Craft craft, final @NotNull CraftDataTagKey<T> tagKey, final @NotNull Function<? super T, ? extends T> computation){