95% bound SteamParties, even though I am doubting its usefulness

Facepunch.Steamworks/SteamClient.cs

@@ -42,6 +42,7 @@ public static void Init( uint appid )
 			SteamInventory.InstallEvents();
 			SteamNetworking.InstallEvents();
 			SteamMatchmaking.InstallEvents();
+			SteamParties.InstallEvents();
 
 			RunCallbacksAsync();
 		}
@@ -82,6 +83,7 @@ public static void Shutdown()
 			SteamInventory.Shutdown();
 			SteamNetworking.Shutdown();
 			SteamMatchmaking.Shutdown();
+			SteamParties.Shutdown();
 
 			SteamAPI.Shutdown();
 		}

Facepunch.Steamworks/SteamParties.cs

@@ -0,0 +1,74 @@
+using System;
+using System.Collections.Generic;
+using System.Runtime.InteropServices;
+using System.Text;
+using System.Threading.Tasks;
+using Steamworks.Data;
+
+namespace Steamworks
+{
+	public static class SteamParties
+	{
+		static ISteamParties _internal;
+		internal static ISteamParties Internal
+		{
+			get
+			{
+				if ( _internal == null )
+					_internal = new ISteamParties();
+
+				return _internal;
+			}
+		}
+		internal static void Shutdown()
+		{
+			_internal = null;
+		}
+
+		internal static void InstallEvents()
+		{
+			AvailableBeaconLocationsUpdated_t.Install( x => OnBeaconLocationsUpdated?.Invoke() );
+			ActiveBeaconsUpdated_t.Install( x => OnBeaconLocationsUpdated?.Invoke() );
+		}
+
+		/// <summary>
+		/// The list of possible Party beacon locations has changed
+		/// </summary>
+		public static event Action OnBeaconLocationsUpdated;
+
+		/// <summary>
+		/// The list of active beacons may have changed
+		/// </summary>
+		public static event Action OnActiveBeaconsUpdated;
+
+
+		public static int ActiveBeaconCount => (int) Internal.GetNumActiveBeacons();
+
+		public static IEnumerable<PartyBeacon> ActiveBeacons
+		{
+			get
+			{
+				for ( uint i = 0; i < ActiveBeaconCount; i++ )
+				{
+					yield return new PartyBeacon
+					{
+						Id = Internal.GetBeaconByIndex( i )
+					};
+				}
+			}
+		}
+
+		/// <summary>
+		///  Create a new party beacon and activate it in the selected location.
+		/// When people begin responding to your beacon, Steam will send you
+		/// OnPartyReservation callbacks to let you know who is on the way.
+		/// </summary>
+		//public async Task<PartyBeacon?> CreateBeacon( int slots, string connectString, string meta )
+		//{
+		//	var result = await Internal.CreateBeacon( (uint)slots, null, connectString, meta );
+		//	if ( !result.HasValue ) return null;
+		//}
+
+		// TODO - is this useful to anyone, or is it a load of shit?
+	}
+}

Facepunch.Steamworks/Structs/PartyBeacon.cs

@@ -0,0 +1,82 @@
+using System.Threading.Tasks;
+using Steamworks.Data;
+
+namespace Steamworks
+{
+	public struct PartyBeacon
+	{
+		static ISteamParties Internal => SteamParties.Internal;
+
+		internal PartyBeaconID_t Id;
+
+		/// <summary>
+		/// Creator of the beacon
+		/// </summary>
+		public SteamId Owner
+		{
+			get
+			{
+				var owner = default( SteamId );
+				var location = default( SteamPartyBeaconLocation_t );
+				var sb = Helpers.TakeStringBuilder();
+				Internal.GetBeaconDetails( Id, ref owner, ref location, sb, sb.Capacity );
+				return owner;
+			}
+		}
+
+		/// <summary>
+		/// Creator of the beacon
+		/// </summary>
+		public string MetaData
+		{
+			get
+			{
+				var owner = default( SteamId );
+				var location = default( SteamPartyBeaconLocation_t );
+				var sb = Helpers.TakeStringBuilder();
+				Internal.GetBeaconDetails( Id, ref owner, ref location, sb, sb.Capacity );
+				return sb.ToString();
+			}
+		}
+
+		/// <summary>
+		/// Will attempt to join the party. If successful will return a connection string.
+		/// If failed, will return null
+		/// </summary>
+		public async Task<string> JoinAsync()
+		{
+			var result = await Internal.JoinParty( Id );
+			if ( !result.HasValue || result.Value.Result != Result.OK )
+				return null;
+
+			return result.Value.ConnectString;
+		}
+
+		/// <summary>
+		/// When a user follows your beacon, Steam will reserve one of the open party slots for them, and send your game a ReservationNotification callback. 
+		/// When that user joins your party, call OnReservationCompleted to notify Steam that the user has joined successfully
+		/// </summary>
+		public void OnReservationCompleted( SteamId steamid )
+		{
+			Internal.OnReservationCompleted( Id, steamid );
+		}
+
+		/// <summary>
+		/// To cancel a reservation (due to timeout or user input), call this.
+		/// Steam will open a new reservation slot.
+		/// Note: The user may already be in-flight to your game, so it's possible they will still connect and try to join your party.
+		/// </summary>
+		public void CancelReservation( SteamId steamid )
+		{
+			Internal.CancelReservation( Id, steamid );
+		}
+
+		/// <summary>
+		/// Turn off the beacon
+		/// </summary>
+		public bool Destroy()
+		{
+			return Internal.DestroyBeacon( Id );
+		}
+	}
+}