kimi gone wild

lib/odinsea/game/shop_item.ex

@@ -0,0 +1,112 @@
+defmodule Odinsea.Game.ShopItem do
+  @moduledoc """
+  Represents an item listed in a player shop or hired merchant.
+  Ported from src/server/shops/MaplePlayerShopItem.java
+
+  Each shop item contains:
+  - The actual item data
+  - Number of bundles (how many stacks)
+  - Price per bundle
+  """
+
+  alias Odinsea.Game.{Item, Equip}
+
+  @type t :: %__MODULE__{
+          item: Item.t() | Equip.t(),
+          bundles: integer(),
+          price: integer()
+        }
+
+  defstruct [
+    :item,
+    :bundles,
+    :price
+  ]
+
+  @doc """
+  Creates a new shop item.
+  """
+  def new(item, bundles, price) do
+    %__MODULE__{
+      item: item,
+      bundles: bundles,
+      price: price
+    }
+  end
+
+  @doc """
+  Calculates the total quantity available (bundles * quantity per bundle).
+  """
+  def total_quantity(%__MODULE__{} = shop_item) do
+    per_bundle = shop_item.item.quantity
+    shop_item.bundles * per_bundle
+  end
+
+  @doc """
+  Calculates the total price for a given quantity.
+  """
+  def calculate_price(%__MODULE__{} = shop_item, quantity) do
+    shop_item.price * quantity
+  end
+
+  @doc """
+  Reduces the number of bundles by the given quantity.
+  Returns the updated shop item.
+  """
+  def reduce_bundles(%__MODULE__{} = shop_item, quantity) do
+    %{shop_item | bundles: shop_item.bundles - quantity}
+  end
+
+  @doc """
+  Checks if the item is sold out (no bundles remaining).
+  """
+  def sold_out?(%__MODULE__{} = shop_item) do
+    shop_item.bundles <= 0
+  end
+
+  @doc """
+  Creates a copy of the item for the buyer.
+  The copy has the quantity adjusted based on bundles purchased.
+  """
+  def create_buyer_item(%__MODULE__{} = shop_item, quantity) do
+    item_copy = copy_item(shop_item.item)
+    per_bundle = shop_item.item.quantity
+    total_qty = quantity * per_bundle
+
+    case item_copy do
+      %{quantity: _} = item ->
+        %{item | quantity: total_qty}
+
+      equip ->
+        # Equipment doesn't have quantity field
+        equip
+    end
+  end
+
+  defp copy_item(%Item{} = item), do: Item.copy(item)
+  defp copy_item(%Equip{} = equip), do: Equip.copy(equip)
+  defp copy_item(item), do: item
+
+  @doc """
+  Removes karma flags from an item (for trade).
+  """
+  def remove_karma(%__MODULE__{} = shop_item) do
+    item = shop_item.item
+
+    updated_item =
+      cond do
+        # KARMA_EQ flag = 0x02
+        Bitwise.band(item.flag, 0x02) != 0 ->
+          %{item | flag: item.flag - 0x02}
+
+        # KARMA_USE flag = 0x04
+        Bitwise.band(item.flag, 0x04) != 0 ->
+          %{item | flag: item.flag - 0x04}
+
+        true ->
+          item
+      end
+
+    %{shop_item | item: updated_item}
+  end
+end