GamecraftRichPresenceMod/GamecraftRPC/MyPlugin.cs

using System;
using System.Reflection;

using IllusionPlugin;
// using GamecraftModdingAPI;
using GamecraftModdingAPI.Commands;
using DiscordRPC;

namespace GamecraftRPC
{
	public class MyPlugin : IPlugin // the Illusion Plugin Architecture (IPA) will ignore classes that don't implement IPlugin'
	{
		public string Name { get; } = Assembly.GetExecutingAssembly().GetName().Name;

		public string Version { get; } = Assembly.GetExecutingAssembly().GetName().Version.ToString();

		private static readonly string CLIENT_ID = "692733325902872619";

        private DiscordRpcClient discordRPC;

        // called when Gamecraft shuts down
		public void OnApplicationQuit()
		{
            // Shutdown this mod
			GamecraftModdingAPI.Utility.Logging.LogDebug($"{Name} has shutdown");

            // Shutdown the Gamecraft modding API last
			GamecraftModdingAPI.Main.Shutdown();
		}

        // called when Gamecraft starts up
		public void OnApplicationStart()
		{
            // Initialize the Gamecraft modding API first
			GamecraftModdingAPI.Main.Init();

			// Initialize this mod
			SimpleCustomCommandEngine rpcCommand = new SimpleCustomCommandEngine(
				() => { }, // TODO: command action
                // also try using CommandLogWarning or CommandLogError instead of CommandLog
				"RPC", // command name (used to invoke it in the console)
                "DiscordRPC Experimental command" // command description (displayed when help command is executed)
			); // this command can also be executed using the Command Computer

            // register the command so the modding API knows about it
			CommandManager.AddCommand(rpcCommand);

			discordRPC = new DiscordRpcClient(CLIENT_ID);

			discordRPC.OnReady += (sender, e) =>
            {
				GamecraftModdingAPI.Utility.Logging.LogDebug($"Received Ready from user {e.User.Username}");
            };

			discordRPC.OnPresenceUpdate += (sender, e) =>
            {
				GamecraftModdingAPI.Utility.Logging.LogDebug($"Received Update! {e.Presence}");
            };

			discordRPC.Initialize();

			discordRPC.SetPresence(new RichPresence()
                {
                    Details = "Gamecraft Rich Presence",
                    State = "Gamecraft RPC test",
                    Assets = new DiscordRPC.Assets()
                    {
                        LargeImageKey = "image_large",
                        LargeImageText = "Testing stuff",
                        SmallImageKey = "image_small"
                    }
                }); 

			GamecraftModdingAPI.Utility.Logging.LogDebug($"{Name} has started up");
		}

        // unused methods

		public void OnFixedUpdate() { } // called once per physics update

		public void OnLevelWasInitialized(int level) { } // called after a level is initialized

		public void OnLevelWasLoaded(int level) { } // called after a level is loaded

		public void OnUpdate() // called once per rendered frame (frame update)
		{
			if (discordRPC != null ) discordRPC.Invoke();
		}
	}
}