Add registry receiving function

registry/registry.go

@@ -1,12 +1,16 @@
 package registry
 
+import "github.com/Tnze/go-mc/nbt"
+
 type Registry[E any] struct {
-	Type  string `nbt:"type"`
-	Value []struct {
-		Name    string `nbt:"name"`
-		ID      int32  `nbt:"id"`
-		Element E      `nbt:"element"`
-	} `nbt:"value"`
+	Type  string     `nbt:"type"`
+	Value []Entry[E] `nbt:"value"`
+}
+
+type Entry[E any] struct {
+	Name    string `nbt:"name"`
+	ID      int32  `nbt:"id"`
+	Element E      `nbt:"element"`
 }
 
 func (r *Registry[E]) Find(name string) (int32, *E) {
@@ -29,3 +33,18 @@ func (r *Registry[E]) FindByID(id int32) *E {
 	}
 	return nil
 }
+
+func (r *Registry[E]) Insert(name string, data E) {
+	r.Value = append(r.Value, Entry[E]{Name: name, Element: data})
+}
+
+func (r *Registry[E]) InsertNBT(name string, data nbt.RawMessage) error {
+	entry := Entry[E]{Name: name, ID: int32(len(r.Value))}
+	if data.Type != 0 {
+		if err := data.UnmarshalDisallowUnknownField(&entry.Element); err != nil {
+			return err
+		}
+	}
+	r.Value = append(r.Value, entry)
+	return nil
+}