Add new API; disable shift click in inventory GUIs

src/main/java/net/citizensnpcs/api/CitizensAPI.java

@@ -84,6 +84,10 @@ private static ClassLoader getImplementationClassLoader() {
         return getImplementation().getOwningClassLoader();
     }
 
+    public static InventoryHelper getInventoryHelper() {
+        return getImplementation().getInventoryHelper();
+    }
+
     /**
      * Retrieves the {@link NPCRegistry} previously created via {@link #createNamedNPCRegistry(String, NPCDataStore)}
      * with the given name, or null if not found.

src/main/java/net/citizensnpcs/api/CitizensPlugin.java

@@ -41,6 +41,8 @@ public interface CitizensPlugin extends Plugin {
      */
     public NPCSelector getDefaultNPCSelector();
 
+    public InventoryHelper getInventoryHelper();
+
     /**
      *
      * @param name

src/main/java/net/citizensnpcs/api/InventoryHelper.java

@@ -0,0 +1,8 @@
+package net.citizensnpcs.api;
+
+import org.bukkit.entity.Player;
+import org.bukkit.inventory.InventoryView;
+
+public interface InventoryHelper {
+    void updateInventoryTitle(Player player, InventoryView view, String newTitle);
+}

src/main/java/net/citizensnpcs/api/gui/InputMenu.java

@@ -1,21 +1,57 @@
 package net.citizensnpcs.api.gui;
 
+import java.util.function.Consumer;
+import java.util.function.Supplier;
+
+import org.bukkit.Material;
 import org.bukkit.event.inventory.InventoryType;
+import org.bukkit.inventory.ItemStack;
+import org.bukkit.inventory.meta.ItemMeta;
+
+import com.google.common.base.Function;
 
 @Menu(type = InventoryType.ANVIL)
 public class InputMenu extends InventoryMenuPage {
+    private final Function<String, Boolean> callback;
     private MenuContext ctx;
+    private final Supplier<String> initialValue;
+    @MenuSlot(slot = { 0, 0 }, material = Material.PAPER, amount = 1)
+    private InventoryMenuSlot slot;
+
+    public InputMenu(Supplier<String> initialValue, Function<String, Boolean> callback) {
+        this.initialValue = initialValue;
+        this.callback = callback;
+    }
 
     @ClickHandler(slot = { 0, 0 })
     public void cancel(InventoryMenuSlot slot, CitizensInventoryClickEvent evt) {
+        evt.setCancelled(true);
+        ctx.getMenu().transitionBack();
     }
 
     @Override
     public void initialise(MenuContext ctx) {
         this.ctx = ctx;
+        ItemStack item = slot.getCurrentItem();
+        ItemMeta meta = item.getItemMeta();
+        meta.setDisplayName(initialValue.get());
+        item.setItemMeta(meta);
     }
 
-    @ClickHandler(slot = { 0, 1 })
+    @ClickHandler(slot = { 0, 2 })
     public void save(InventoryMenuSlot slot, CitizensInventoryClickEvent evt) {
+        evt.setCancelled(true);
+        if (callback.apply(slot.getCurrentItem().getItemMeta().getDisplayName())) {
+            ctx.getMenu().transitionBack();
+        } else {
+            evt.setCancelled(true);
+        }
+    }
+
+    public static InputMenu setter(Supplier<String> initialValue, Consumer<String> callback) {
+        return new InputMenu(initialValue, (s) -> {
+            callback.accept(s);
+            return true;
+        });
     }
 }

src/main/java/net/citizensnpcs/api/gui/InventoryMenu.java

@@ -197,6 +197,8 @@ private int getInventorySize(InventoryType type, int[] dim) {
     }
 
     private void handleShiftClick(InventoryClickEvent event, Inventory dest, boolean toNPC) {
+        if (event.getCurrentItem() == null)
+            return;
         int amount = event.getCurrentItem().getAmount();
         ItemStack merging = new ItemStack(event.getCurrentItem().clone());
         ItemStack[] contents = dest.getContents();
@@ -259,10 +261,11 @@ public void onInventoryClick(InventoryClickEvent event) {
             Inventory dest = event.getInventory() == event.getClickedInventory() ? event.getWhoClicked().getInventory()
                     : page.ctx.getInventory();
             boolean toNPC = dest == page.ctx.getInventory();
-            if ((event.getCursor() == null || event.getCursor().getType() == Material.AIR)) {
+            if (false) {
+                // TODO
                 handleShiftClick(event, dest, toNPC);
-                return;
             }
+            return;
         }
         if (!clicked.equals(page.ctx.getInventory()))
             return;
@@ -374,6 +377,12 @@ public void run() {
         page.page.run();
     }
 
+    public void setTitle(String newTitle) {
+        for (InventoryView view : views) {
+            CitizensAPI.getInventoryHelper().updateInventoryTitle((Player) view.getPlayer(), view, newTitle);
+        }
+    }
+
     /**
      * Transition to another page. Adds the previous page to a stack which will be returned to when the current page is
      * closed.
@@ -516,7 +525,9 @@ private void transitionViewersToInventory(Inventory inventory) {
             view.close();
             if (!view.getPlayer().isValid() || inventory == null)
                 continue;
-            views.add(view.getPlayer().openInventory(inventory));
+            InventoryView newview = view.getPlayer().openInventory(inventory);
+            // TODO: fix anvil inventory
+            views.add(newview);
         }
     }
 
@@ -558,6 +569,8 @@ public InventoryMenuInfo(Class<?> clazz) {
         }
 
         public InventoryMenuPage createInstance() {
+            if (constructor == null)
+                throw new RuntimeException("no constructor provided");
             try {
                 return constructor.newInstance();
             } catch (Exception e) {
@@ -675,6 +688,7 @@ private static void cacheInfo(Class<? extends InventoryMenuPage> clazz) {
             Constructor<? extends InventoryMenuPage> found = clazz.getDeclaredConstructor();
             found.setAccessible(true);
             info.constructor = found;
+        } catch (NoSuchMethodException e2) {
         } catch (Exception e) {
             throw new RuntimeException(e);
         }