SDL2Gamepad for Unity

using UnityEngine;
using System.Collections;
using System;
using SDL2;

public class SDL2Gamepad : MonoBehaviour {
	private System.IntPtr gamecontroller = System.IntPtr.Zero;
	private int m_device = 0;

	private void Awake() {
		/* Enable standard application logging */
		SDL.SDL_LogSetPriority(SDL.SDL_LOG_CATEGORY_APPLICATION, SDL.SDL_LogPriority.SDL_LOG_PRIORITY_INFO);

		/* Initialize SDL (Note: video is required to start event loop) */
		int ret = SDL.SDL_Init(SDL.SDL_INIT_JOYSTICK | SDL.SDL_INIT_GAMECONTROLLER);
		print("SDL_Init() - " + ret);
		if (ret < 0) {
			//SDL.SDL_LogError(SDL.SDL_LOG_CATEGORY_APPLICATION, string.Format("Couldn't initialize SDL: {0}\n", SDL.SDL_GetError()));
			Debug.LogError(string.Format("Couldn't initialize SDL: {0}\n", SDL.SDL_GetError()));
			return;
		}

		//SDL.SDL_GameControllerAddMapping(""); //TODO


		int nController = 0;
		byte[] guid2 = new byte[64];
		string guid;

		/* Print information about the controller */
		for (int i = 0; i < SDL.SDL_NumJoysticks(); ++i) {
			string name;
			string description;

			SDL.SDL_JoystickGetGUIDString(SDL.SDL_JoystickGetDeviceGUID(i), guid2, guid2.Length);
			guid = System.Text.Encoding.UTF8.GetString(guid2).Trim('\0'); 

			if (SDL.SDL_IsGameController(i) == SDL.SDL_bool.SDL_TRUE) {
				m_device = i;
				nController++;
				name = SDL.SDL_GameControllerNameForIndex(i);
				description = "Controller";
			}
			else {
				name = SDL.SDL_JoystickNameForIndex(i);
				description = "Joystick";
			}
			//SDL.SDL_Log(string.Format("{0} {1}: {2} (guid {3})\n", description, i, string.IsNullOrEmpty(name) ? name : "Unknown", guid));
			Debug.Log(string.Format("{0} {1}: {2} (guid {3})", description, i, string.IsNullOrEmpty(name) ? "Unknown" : name, guid));
		}
		//SDL.SDL_Log(string.Format("There are {0} game controller(s) attached ({1} joystick(s))\n", nController, SDL.SDL_NumJoysticks()));
		Debug.Log(string.Format("There are {0} game controller(s) attached ({1} joystick(s))", nController, SDL.SDL_NumJoysticks()));

		if (nController > 0) {
			SDL.SDL_JoystickGetGUIDString(SDL.SDL_JoystickGetDeviceGUID(m_device), guid2, guid2.Length);
			guid = System.Text.Encoding.UTF8.GetString(guid2).Trim('\0');

			//SDL.SDL_Log(string.Format("Attempting to open device {0}, guid {1}\n", device, guid));
			Debug.Log(string.Format("Attempting to open device {0}, guid {1}\n", m_device, guid));
			gamecontroller = SDL.SDL_GameControllerOpen(m_device);

			if (gamecontroller == System.IntPtr.Zero) {
				//SDL.SDL_LogError(SDL.SDL_LOG_CATEGORY_APPLICATION, string.Format("Couldn't open gamecontroller {0}: {1}\n", m_device, SDL.SDL_GetError()));
				Debug.LogError(string.Format("Couldn't open gamecontroller {0}: {1}\n", m_device, SDL.SDL_GetError()));
			}

#if DISABLED
			/* Create a window to display controller state */
			System.IntPtr window = SDL.SDL_CreateWindow("Title", SDL.SDL_WINDOWPOS_CENTERED, SDL.SDL_WINDOWPOS_CENTERED, 500, 500, 0);
			if (window == System.IntPtr.Zero) {
				//SDL.SDL_LogError(SDL.SDL_LOG_CATEGORY_APPLICATION, string.Format("Couldn't create window: {0}\n", SDL.SDL_GetError()));
				Debug.Log(string.Format("Couldn't create window: {0}\n", SDL.SDL_GetError()));
				return;
			}

			System.IntPtr screen = SDL.SDL_CreateRenderer(window, -1, 0);
			if (screen == System.IntPtr.Zero) {
				//SDL.SDL_LogError(SDL.SDL_LOG_CATEGORY_APPLICATION, string.Format("Couldn't create renderer: {0}\n", SDL.SDL_GetError()));
				Debug.Log(string.Format("Couldn't create renderer: {0}\n", SDL.SDL_GetError()));
				SDL.SDL_DestroyWindow(window);
				return;
			}

			SDL.SDL_SetRenderDrawColor(screen, 0x00, 0x00, 0x00, 255);
			SDL.SDL_RenderClear(screen);
			SDL.SDL_RenderPresent(screen);
			SDL.SDL_RaiseWindow(window);

			/* scale for platforms that don't give you the window size you asked for. */
			SDL.SDL_RenderSetLogicalSize(screen, 500, 500);
#endif
		}
	}

	private void OnDestroy() {
		SDL.SDL_GameControllerClose(gamecontroller);
		SDL.SDL_QuitSubSystem(SDL.SDL_INIT_VIDEO | SDL.SDL_INIT_JOYSTICK | SDL.SDL_INIT_GAMECONTROLLER);
	}

	private void Update() {
		SDL.SDL_Event _event;
		while (SDL.SDL_PollEvent(out _event) != 0) {
			print(_event.type);
			switch (_event.type) {
				case SDL.SDL_EventType.SDL_CONTROLLERDEVICEADDED:
					if (gamecontroller == System.IntPtr.Zero) {
						gamecontroller = SDL.SDL_GameControllerOpen(_event.cdevice.which);
						m_device = _event.cdevice.which;
					}
					break;
				case SDL.SDL_EventType.SDL_MOUSEBUTTONDOWN:
					Debug.Log("SDL_MOUSEBUTTONDOWN");
					goto case SDL.SDL_EventType.SDL_QUIT;
				case SDL.SDL_EventType.SDL_KEYDOWN:
					Debug.Log("SDL_KEYDOWN: " + _event.key.keysym.sym);
					goto case SDL.SDL_EventType.SDL_QUIT;
                /* Fall through to signal quit */
				case SDL.SDL_EventType.SDL_QUIT:
					Debug.Log("SDL_QUIT");
					break;
				default:
					break;
            }
		}

		if (gamecontroller == System.IntPtr.Zero) {
			return;
		}

		for (int i = 0; i < (int)SDL.SDL_GameControllerButton.SDL_CONTROLLER_BUTTON_MAX; ++i) {
			if (SDL.SDL_GameControllerGetButton(gamecontroller, (SDL.SDL_GameControllerButton)i) == SDL.SDL_PRESSED) {
				Debug.Log("Button " + i + " is pressed");
			}
		}

		for (int i = 0; i < (int)SDL.SDL_GameControllerAxis.SDL_CONTROLLER_AXIS_MAX; ++i) {
			const short deadzone = 8000;  /* !!! FIXME: real deadzone */
			short value = SDL.SDL_GameControllerGetAxis(gamecontroller, (SDL.SDL_GameControllerAxis)(i));
			if (value < -deadzone || value > deadzone) {
				Debug.Log(value);
			}
		}

		if (SDL.SDL_GameControllerGetAttached(gamecontroller) != SDL.SDL_bool.SDL_TRUE) {
			SDL.SDL_GameControllerClose(gamecontroller);
			gamecontroller = System.IntPtr.Zero;
			//SDL.SDL_Log("Waiting for attach\n");
			Debug.Log("Waiting for reattach");
		}
	}
}