add getShopBySignLocation(Location signLocation) to api

plugin/src/main/java/com/alttd/playershops/listener/ShopListener.java

@@ -1,6 +1,15 @@
 package com.alttd.playershops.listener;
 
 import com.alttd.playershops.PlayerShops;
+import com.alttd.playershops.api.Shop;
+import com.alttd.playershops.config.Config;
+import org.bukkit.Location;
+import org.bukkit.Tag;
+import org.bukkit.block.Block;
+import org.bukkit.event.EventHandler;
+import org.bukkit.event.entity.EntityExplodeEvent;
+
+import java.util.Iterator;
 
 public class ShopListener extends EventListener {
 
@@ -10,4 +19,26 @@ public class ShopListener extends EventListener {
         this.plugin = plugin;
         this.register(this.plugin);
     }
+
+    @EventHandler(ignoreCancelled = true)
+    public void onEntityExplosion(EntityExplodeEvent event) {
+        if(!this.isRegistered) return;
+
+        Iterator<Block> blockIterator = event.blockList().iterator();
+        Shop shop = null;
+        while (blockIterator.hasNext()) {
+
+            Block block = blockIterator.next();
+            Location location = block.getLocation();
+            if (Tag.WALL_SIGNS.isTagged(block.getType())) {
+                shop = plugin.getShopHandler().getShopBySignLocation(location);
+            } else if (plugin.getShopHandler().isShopMaterial(block)) {
+                shop = plugin.getShopHandler().getShop(location);
+            }
+
+            if (shop != null) {
+                blockIterator.remove();
+            }
+        }
+    }
 }