From 87adbb477d5da476cf0647798c7157e1110bd19f Mon Sep 17 00:00:00 2001
From: Ali Moghnieh <supaham@supaham.com>
Date: Fri, 22 Jul 2016 23:56:26 +0100
Subject: [PATCH] Allow bulk buy/sell when sneaking. Resolves #65

---
 .../src/com/earth2me/essentials/User.java     | 14 ++++++++++
 .../earth2me/essentials/signs/SignBuy.java    | 26 +++++++++++++++++--
 .../earth2me/essentials/signs/SignSell.java   | 26 +++++++++++++++++--
 3 files changed, 62 insertions(+), 4 deletions(-)

diff --git a/Essentials/src/com/earth2me/essentials/User.java b/Essentials/src/com/earth2me/essentials/User.java
index 07c8716e9..7908e01ef 100644
--- a/Essentials/src/com/earth2me/essentials/User.java
+++ b/Essentials/src/com/earth2me/essentials/User.java
@@ -19,6 +19,8 @@ import org.bukkit.ChatColor;
 import org.bukkit.Location;
 import org.bukkit.entity.Player;
 import org.bukkit.event.player.PlayerTeleportEvent.TeleportCause;
+import org.bukkit.inventory.ItemStack;
+import org.bukkit.inventory.PlayerInventory;
 import org.bukkit.potion.PotionEffect;
 import org.bukkit.potion.PotionEffectType;
 
@@ -787,4 +789,16 @@ public class User extends UserData implements Comparable<User>, IMessageRecipien
             this.afkMessage = message;
         }
     }
+
+    /**
+     * Returns the {@link ItemStack} in the main hand or off-hand. If the main hand is empty then the offhand item is returned - also nullable.
+     */
+    public ItemStack getItemInHand() {
+        if (ReflUtil.getNmsVersionObject().isLowerThan(ReflUtil.V1_9_R1)) {
+            return getBase().getInventory().getItemInHand();
+        } else {
+            PlayerInventory inventory = getBase().getInventory();
+            return inventory.getItemInMainHand() != null ? inventory.getItemInMainHand() : inventory.getItemInOffHand();
+        }
+    }
 }
diff --git a/Essentials/src/com/earth2me/essentials/signs/SignBuy.java b/Essentials/src/com/earth2me/essentials/signs/SignBuy.java
index c2d51afe3..48e65849f 100644
--- a/Essentials/src/com/earth2me/essentials/signs/SignBuy.java
+++ b/Essentials/src/com/earth2me/essentials/signs/SignBuy.java
@@ -6,6 +6,10 @@ import com.earth2me.essentials.User;
 import net.ess3.api.IEssentials;
 import net.ess3.api.MaxMoneyException;
 
+import org.bukkit.inventory.ItemStack;
+
+import java.math.BigDecimal;
+
 
 public class SignBuy extends EssentialsSign {
     public SignBuy() {
@@ -21,8 +25,26 @@ public class SignBuy extends EssentialsSign {
 
     @Override
     protected boolean onSignInteract(final ISign sign, final User player, final String username, final IEssentials ess) throws SignException, ChargeException, MaxMoneyException {
-        final Trade items = getTrade(sign, 1, 2, player, ess);
-        final Trade charge = getTrade(sign, 3, ess);
+        Trade items = getTrade(sign, 1, 2, player, ess);
+        Trade charge = getTrade(sign, 3, ess);
+
+        // Check if the player is trying to buy in bulk.
+        if (player.getBase().isSneaking()) {
+            ItemStack heldItem = player.getItemInHand();
+            if (items.getItemStack().isSimilar(heldItem)) {
+                int initialItemAmount = items.getItemStack().getAmount();
+                int newItemAmount = heldItem.getAmount();
+                ItemStack item = items.getItemStack();
+                item.setAmount(newItemAmount);
+                items = new Trade(item, ess);
+
+                BigDecimal chargeAmount = charge.getMoney();
+                BigDecimal pricePerSingleItem = chargeAmount.divide(new BigDecimal(initialItemAmount));
+                pricePerSingleItem = pricePerSingleItem.multiply(new BigDecimal(newItemAmount));
+                charge = new Trade(pricePerSingleItem, ess);
+            }
+        }
+
         charge.isAffordableFor(player);
         if (!items.pay(player)) {
             throw new ChargeException("Inventory full"); //TODO: TL
diff --git a/Essentials/src/com/earth2me/essentials/signs/SignSell.java b/Essentials/src/com/earth2me/essentials/signs/SignSell.java
index 55a17870f..ff8353793 100644
--- a/Essentials/src/com/earth2me/essentials/signs/SignSell.java
+++ b/Essentials/src/com/earth2me/essentials/signs/SignSell.java
@@ -7,6 +7,10 @@ import com.earth2me.essentials.User;
 import net.ess3.api.IEssentials;
 import net.ess3.api.MaxMoneyException;
 
+import org.bukkit.inventory.ItemStack;
+
+import java.math.BigDecimal;
+
 
 public class SignSell extends EssentialsSign {
     public SignSell() {
@@ -22,8 +26,26 @@ public class SignSell extends EssentialsSign {
 
     @Override
     protected boolean onSignInteract(final ISign sign, final User player, final String username, final IEssentials ess) throws SignException, ChargeException, MaxMoneyException {
-        final Trade charge = getTrade(sign, 1, 2, player, ess);
-        final Trade money = getTrade(sign, 3, ess);
+        Trade charge = getTrade(sign, 1, 2, player, ess);
+        Trade money = getTrade(sign, 3, ess);
+
+        // Check if the player is trying to sell in bulk.
+        if (player.getBase().isSneaking()) {
+            ItemStack heldItem = player.getItemInHand();
+            if (charge.getItemStack().isSimilar(heldItem)) {
+                int initialItemAmount = charge.getItemStack().getAmount();
+                int newItemAmount = heldItem.getAmount();
+                ItemStack item = charge.getItemStack();
+                item.setAmount(newItemAmount);
+                charge = new Trade(item, ess);
+
+                BigDecimal chargeAmount = money.getMoney();
+                BigDecimal pricePerSingleItem = chargeAmount.divide(new BigDecimal(initialItemAmount));
+                pricePerSingleItem = pricePerSingleItem.multiply(new BigDecimal(newItemAmount));
+                money = new Trade(pricePerSingleItem, ess);
+            }
+        }
+
         charge.isAffordableFor(player);
         money.pay(player, OverflowType.DROP);
         charge.charge(player);