Pastes default nether or end blueprints if island doesn't exist

Fixes issue where the nether-island or end-island named blueprints were
deleted.

https://github.com/BentoBoxWorld/BentoBox/issues/943

src/main/java/world/bentobox/bentobox/blueprints/BlueprintPaster.java

@@ -94,7 +94,7 @@ public class BlueprintPaster {
      * @param island - island related to this paste
      * @param task - task to run after pasting
      */
-    public BlueprintPaster(@NonNull BentoBox plugin, Blueprint bp, World world, Island island, Runnable task) {
+    public BlueprintPaster(@NonNull BentoBox plugin, @NonNull Blueprint bp, World world, Island island, Runnable task) {
         this.plugin = plugin;
         // Offset due to bedrock
         Vector off = bp.getBedrock() != null ? bp.getBedrock() : new Vector(0,0,0);

src/main/java/world/bentobox/bentobox/listeners/PortalTeleportationListener.java

@@ -15,7 +15,9 @@ import org.bukkit.event.player.PlayerTeleportEvent.TeleportCause;
 import org.eclipse.jdt.annotation.NonNull;
 
 import world.bentobox.bentobox.BentoBox;
+import world.bentobox.bentobox.blueprints.Blueprint;
 import world.bentobox.bentobox.blueprints.BlueprintPaster;
+import world.bentobox.bentobox.blueprints.dataobjects.BlueprintBundle;
 import world.bentobox.bentobox.database.objects.Island;
 import world.bentobox.bentobox.util.Util;
 import world.bentobox.bentobox.util.teleport.SafeSpotTeleport;
@@ -197,15 +199,24 @@ public class PortalTeleportationListener implements Listener {
      * @param env - NETHER or THE_END
      */
     private void pasteNewIsland(Player player, Location to, Island island, Environment env) {
-        String name = env.equals(Environment.NETHER) ? "nether-island" : "end-island";
         // Paste then teleport player
-        plugin.getIWM().getAddon(island.getWorld()).ifPresent(addon
-                -> new BlueprintPaster(plugin, plugin.getBlueprintsManager().getBlueprints(addon).get(name),
-                        to.getWorld(),
-                        island, () -> new SafeSpotTeleport.Builder(plugin)
-                        .entity(player)
-                        .location(island.getSpawnPoint(env) == null ? to : island.getSpawnPoint(env))
-                        // No need to use portal because there will be no portal on the other end
-                        .build()));
+        plugin.getIWM().getAddon(island.getWorld()).ifPresent(addon -> {
+            // Get the default bundle's nether or end blueprint
+            BlueprintBundle bb = plugin.getBlueprintsManager().getDefaultBlueprintBundle(addon);
+            if (bb != null) {
+                Blueprint bp = plugin.getBlueprintsManager().getBlueprints(addon).get(bb.getBlueprint(env));
+                if (bp != null) {
+                    new BlueprintPaster(plugin, bp,
+                            to.getWorld(),
+                            island, () -> new SafeSpotTeleport.Builder(plugin)
+                            .entity(player)
+                            .location(island.getSpawnPoint(env) == null ? to : island.getSpawnPoint(env))
+                            // No need to use portal because there will be no portal on the other end
+                            .build());
+                } else {
+                    plugin.logError("Could not paste default island in nether or end. Is there a nether-island or end-island blueprint?");
+                }
+            }
+        });
     }
 }

src/main/java/world/bentobox/bentobox/managers/BlueprintsManager.java

@@ -142,6 +142,19 @@ public class BlueprintsManager {
         return blueprintBundles.get(addon).stream().collect(Collectors.toMap(BlueprintBundle::getUniqueId, b -> b));
     }
 
+    /**
+     * Get the default blueprint bundle for game mode
+     * @param addon - game mode addon
+     * @return the default blueprint bundle or null if none
+     * @since 1.8.0
+     */
+    public BlueprintBundle getDefaultBlueprintBundle(@NonNull GameModeAddon addon) {
+        if (blueprintBundles.containsKey(addon)) {
+            return blueprintBundles.get(addon).stream().filter(bb -> bb.getUniqueId().equals(DEFAULT_BUNDLE_NAME)).findFirst().orElse(null);
+        }
+        return null;
+    }
+
     /**
      * Returns a {@link File} instance of the blueprints folder of this {@link GameModeAddon}.
      *

src/test/java/world/bentobox/bentobox/listeners/PortalTeleportationListenerTest.java

@@ -166,7 +166,7 @@ public class PortalTeleportationListenerTest {
     @Test
     public void testOnEndIslandPortalNoEndWorldGenerated() {
         Location from = mock(Location.class);
-        // Teleport from world to nether
+        // Teleport from world to end
         when(from.getWorld()).thenReturn(world);
         when(from.toVector()).thenReturn(new Vector(1,2,3));
         // No end world