// --------------------------------------------------------------------------------------------------------------------
// <copyright file="EventSystemSpawner.cs" company="Exit Games GmbH">
// </copyright>
// <summary>
// For additive Scene Loading context, eventSystem can't be added to each scene and instead should be instanciated only if necessary.
// https://answers.unity.com/questions/1403002/multiple-eventsystem-in-scene-this-is-not-supporte.html
// </summary>
// <author>developer@exitgames.com</author>
// --------------------------------------------------------------------------------------------------------------------

using UnityEngine;
using UnityEngine.EventSystems;

namespace Photon.Chat.UtilityScripts
{
	/// <summary>
	/// Event system spawner. Will add an EventSystem GameObject with an EventSystem component and a StandaloneInputModule component
	/// Use this in additive scene loading context where you would otherwise get a "Multiple eventsystem in scene... this is not supported" error from Unity
	/// </summary>
	public class EventSystemSpawner : MonoBehaviour 
	{
		void Start()
		{
			EventSystem sceneEventSystem = FindObjectOfType<EventSystem>();
			if (sceneEventSystem == null)
			{
				GameObject eventSystem = new GameObject("EventSystem");

				eventSystem.AddComponent<EventSystem>();
				eventSystem.AddComponent<StandaloneInputModule>();
			}
		}
	}
}