1 files changed, 27 insertions, 0 deletions
diff --git a/src/main/java/gregtech/api/interfaces/covers/IControlsWorkCover.java b/src/main/java/gregtech/api/interfaces/covers/IControlsWorkCover.java
new file mode 100644
index 0000000000..7c2361af83
--- /dev/null
+++ b/src/main/java/gregtech/api/interfaces/covers/IControlsWorkCover.java
@@ -0,0 +1,27 @@
+package gregtech.api.interfaces.covers;
+
+import gregtech.api.interfaces.tileentity.ICoverable;
+import gregtech.api.interfaces.tileentity.IMachineProgress;
+
+/**
+ * Marker interface for covers that might control whether the work can start on a {@link IMachineProgress}.
+ */
+public interface IControlsWorkCover {
+
+    /**
+     * Make sure there is only one GT_Cover_ControlsWork on the aTileEntity
+     * TODO this is a migration thing. Remove this after 2.3.0 is released.
+     *
+     * @return true if the cover is the first (side) one
+     **/
+    static boolean makeSureOnlyOne(byte aMySide, ICoverable aTileEntity) {
+        for (byte i = 0; i < 6; i++) {
+            if (aTileEntity.getCoverBehaviorAtSideNew(i) instanceof IControlsWorkCover && i < aMySide) {
+                aTileEntity.dropCover(i, i, true);
+                aTileEntity.markDirty();
+                return false;
+            }
+        }
+        return true;
+    }
+}