Add EnchantmentOffer to PrepareItemEnchantEvent

By: LukBukkit <luk.bukkit@gmail.com>

paper-api/src/main/java/org/bukkit/enchantments/EnchantmentOffer.java

@@ -0,0 +1,81 @@
+package org.bukkit.enchantments;
+
+import org.apache.commons.lang.Validate;
+
+/**
+ * A class for the available enchantment offers in the enchantment table.
+ */
+public class EnchantmentOffer {
+
+    private Enchantment enchantment;
+    private int enchantmentLevel;
+    private int cost;
+
+    public EnchantmentOffer(Enchantment enchantment, int enchantmentLevel, int cost) {
+        this.enchantment = enchantment;
+        this.enchantmentLevel = enchantmentLevel;
+        this.cost = cost;
+    }
+
+    /**
+     * Get the type of the enchantment.
+     *
+     * @return type of enchantment
+     */
+    public Enchantment getEnchantment() {
+        return enchantment;
+    }
+
+    /**
+     * Sets the type of the enchantment.
+     *
+     * @param enchantment type of the enchantment
+     */
+    public void setEnchantment(Enchantment enchantment) {
+        Validate.notNull(enchantment, "The enchantment may not be null!");
+
+        this.enchantment = enchantment;
+    }
+
+    /**
+     * Gets the level of the enchantment.
+     *
+     * @return level of the enchantment
+     */
+    public int getEnchantmentLevel() {
+        return enchantmentLevel;
+    }
+
+    /**
+     * Sets the level of the enchantment.
+     *
+     * @param enchantmentLevel level of the enchantment
+     */
+    public void setEnchantmentLevel(int enchantmentLevel) {
+        Validate.isTrue(enchantmentLevel > 0, "The enchantment level must be greater than 0!");
+
+        this.enchantmentLevel = enchantmentLevel;
+    }
+
+    /**
+     * Gets the cost in experience levels the player has to pay to enchant his
+     * item with this enchantment.
+     *
+     * @return cost for this enchantment
+     */
+    public int getCost() {
+        return cost;
+    }
+
+    /**
+     * Sets the cost in experience levels the player has to pay to enchant his
+     * item with this enchantment
+     *
+     * @param cost cost for this enchantment
+     */
+    public void setCost(int cost) {
+        Validate.isTrue(cost > 0, "The cost must be greater than 0!");
+
+        this.cost = cost;
+    }
+}

paper-api/src/main/java/org/bukkit/event/enchantment/PrepareItemEnchantEvent.java

@@ -1,6 +1,7 @@
 package org.bukkit.event.enchantment;
 
 import org.bukkit.block.Block;
+import org.bukkit.enchantments.EnchantmentOffer;
 import org.bukkit.entity.Player;
 import org.bukkit.event.Cancellable;
 import org.bukkit.event.HandlerList;
@@ -16,19 +17,18 @@ public class PrepareItemEnchantEvent extends InventoryEvent implements Cancellab
     private static final HandlerList handlers = new HandlerList();
     private final Block table;
     private final ItemStack item;
-    private final int[] levelsOffered;
+    private final EnchantmentOffer[] offers;
     private final int bonus;
     private boolean cancelled;
     private final Player enchanter;
 
-    public PrepareItemEnchantEvent(final Player enchanter, InventoryView view, final Block table, final ItemStack item, final int[] levelsOffered, final int bonus) {
+    public PrepareItemEnchantEvent(final Player enchanter, InventoryView view, final Block table, final ItemStack item, final EnchantmentOffer[] offers, final int bonus) {
         super(view);
         this.enchanter = enchanter;
         this.table = table;
         this.item = item;
-        this.levelsOffered = levelsOffered;
+        this.offers = offers;
         this.bonus = bonus;
-        this.cancelled = false;
     }
 
     /**
@@ -50,7 +50,7 @@ public class PrepareItemEnchantEvent extends InventoryEvent implements Cancellab
     }
 
     /**
-     * Gets the item to be enchanted (can be modified)
+     * Gets the item to be enchanted.
      *
      * @return ItemStack of item
      */
@@ -59,13 +59,29 @@ public class PrepareItemEnchantEvent extends InventoryEvent implements Cancellab
     }
 
     /**
-     * Get list of offered exp level costs of the enchantment (modify values
+     * Get a list of offered experience level costs of the enchantment.
-     * to change offer)
      *
      * @return experience level costs offered
+     * @deprecated Use {@link #getOffers()} instead of this method
      */
     public int[] getExpLevelCostsOffered() {
-        return levelsOffered;
+        int[] levelOffers = new int[offers.length];
+        for (int i = 0; i < offers.length; i++) {
+            levelOffers[i] = offers[i] != null ? offers[i].getCost() : 0;
+        }
+        return levelOffers;
+    }
+
+    /**
+     * Get a list of available {@link EnchantmentOffer} for the player. You can
+     * modify the values to change the available offers for the player. An offer
+     * may be null, if there isn't a enchantment offer at a specific slot. There
+     * are 3 slots in the enchantment table available to modify.
+     *
+     * @return list of available enchantment offers
+     */
+    public EnchantmentOffer[] getOffers() {
+        return offers;
     }
 
     /**
@@ -77,10 +93,12 @@ public class PrepareItemEnchantEvent extends InventoryEvent implements Cancellab
         return bonus;
     }
 
+    @Override
     public boolean isCancelled() {
         return cancelled;
     }
 
+    @Override
     public void setCancelled(boolean cancel) {
         this.cancelled = cancel;
     }