From 18f81573f5ce1983d64395f951ef45808b43b5a5 Mon Sep 17 00:00:00 2001
From: Garry Newman <garrynewman@users.noreply.github.com>
Date: Tue, 7 May 2019 21:25:41 +0100
Subject: [PATCH] Added CraftItemAsync with Amounts

---
 Facepunch.Steamworks/SteamInventory.cs        | 21 +++++++++++++++++++
 Facepunch.Steamworks/Structs/InventoryItem.cs |  9 ++++++++
 2 files changed, 30 insertions(+)

diff --git a/Facepunch.Steamworks/SteamInventory.cs b/Facepunch.Steamworks/SteamInventory.cs
index 94c2a79..18d8a86 100644
--- a/Facepunch.Steamworks/SteamInventory.cs
+++ b/Facepunch.Steamworks/SteamInventory.cs
@@ -239,6 +239,27 @@ namespace Steamworks
 			return await InventoryResult.GetAsync( sresult );
 		}
 
+		/// <summary>
+		/// Crafting! Uses the passed items to buy the target item.
+		/// You need to have set up the appropriate exchange rules in your item
+		/// definitions. This assumes all the items passed in aren't stacked.
+		/// </summary>
+		public static async Task<InventoryResult?> CraftItemAsync( InventoryItem.Amount[] list, InventoryDef target )
+		{
+			var sresult = default( SteamInventoryResult_t );
+
+			var give = new InventoryDefId[] { target.Id };
+			var givec = new uint[] { 1 };
+
+			var sell = list.Select( x => x.Item.Id ).ToArray();
+			var sellc = list.Select( x => (uint) x.Quantity ).ToArray();
+
+			if ( !Internal.ExchangeItems( ref sresult, give, givec, 1, sell, sellc, (uint)sell.Length ) )
+				return null;
+
+			return await InventoryResult.GetAsync( sresult );
+		}
+
 		/// <summary>
 		/// Deserializes a result set and verifies the signature bytes.	
 		/// This call has a potential soft-failure mode where the Result is expired, it will 
diff --git a/Facepunch.Steamworks/Structs/InventoryItem.cs b/Facepunch.Steamworks/Structs/InventoryItem.cs
index c33ba66..7036d1a 100644
--- a/Facepunch.Steamworks/Structs/InventoryItem.cs
+++ b/Facepunch.Steamworks/Structs/InventoryItem.cs
@@ -122,5 +122,14 @@ namespace Steamworks
 
 			return props;
 		}
+
+		/// <summary>
+		/// Small utility class to describe an item with a quantity
+		/// </summary>
+		public struct Amount
+		{
+			public InventoryItem Item;
+			public int Quantity;
+		}
 	}
 }
\ No newline at end of file