Refactor Carpet's sticky blocks code (#1505)

refactor sticky blocks code

src/main/java/carpet/mixins/ChainBlock_customStickyMixin.java

@@ -0,0 +1,46 @@
+package carpet.mixins;
+
+import org.spongepowered.asm.mixin.Mixin;
+
+import carpet.CarpetSettings;
+import carpet.fakes.BlockBehaviourInterface;
+
+import net.minecraft.core.BlockPos;
+import net.minecraft.core.Direction;
+import net.minecraft.core.Direction.Axis;
+import net.minecraft.world.level.Level;
+import net.minecraft.world.level.block.Block;
+import net.minecraft.world.level.block.Blocks;
+import net.minecraft.world.level.block.ChainBlock;
+import net.minecraft.world.level.block.EndRodBlock;
+import net.minecraft.world.level.block.state.BlockState;
+
+@Mixin(ChainBlock.class)
+public class ChainBlock_customStickyMixin implements BlockBehaviourInterface {
+
+    @Override
+    public boolean isSticky(BlockState state) {
+        return CarpetSettings.doChainStone;
+    }
+
+    @Override
+    public boolean isStickyToNeighbor(Level level, BlockPos pos, BlockState state, BlockPos neighborPos, BlockState neighborState, Direction dir, Direction moveDir) {
+        Axis axis = state.getValue(ChainBlock.AXIS);
+
+        if (axis != dir.getAxis()) {
+            return false;
+        }
+
+        if (CarpetSettings.chainStoneStickToAll) {
+            return true;
+        }
+        if (neighborState.is((Block)(Object)this)) {
+            return axis == neighborState.getValue(ChainBlock.AXIS);
+        }
+        if (neighborState.is(Blocks.END_ROD)) {
+            return axis == neighborState.getValue(EndRodBlock.FACING).getAxis();
+        }
+
+        return Block.canSupportCenter(level, neighborPos, dir.getOpposite());
+    }
+}