// (c) Copyright HutongGames, LLC 2010-2013. All rights reserved.

using UnityEngine;
using System;

namespace HutongGames.PlayMaker.Actions
{
	[ActionCategory(ActionCategory.GUIElement)]
	[Tooltip("Performs a Hit Test on a Game Object with a GUITexture or GUIText component.")]
    #if UNITY_2019_3_OR_NEWER
    [Obsolete("GUIElement is part of the legacy UI system removed in 2019.3")]
	#elif UNITY_2017_2_OR_NEWER
	#pragma warning disable CS0618  
	[Obsolete("GUIElement is part of the legacy UI system and will be removed in a future release")]
	#endif

	public class GUIElementHitTest : FsmStateAction
	{
		[RequiredField]
#if !UNITY_2019_3_OR_NEWER
		[CheckForComponent(typeof(GUIElement))]
#else
        [ActionSection("Obsolete. Use Unity UI instead.")]
#endif
		[Tooltip("The GameObject that has a GUITexture or GUIText component.")]
		public FsmOwnerDefault gameObject;
		[Tooltip("Specify camera or use MainCamera as default.")]
		public Camera camera;
		[Tooltip("A vector position on screen. Usually stored by actions like GetTouchInfo, or World To Screen Point.")]
		public FsmVector3 screenPoint;
		[Tooltip("Specify screen X coordinate.")]
		public FsmFloat screenX;
		[Tooltip("Specify screen Y coordinate.")]
		public FsmFloat screenY;
		[Tooltip("Whether the specified screen coordinates are normalized (0-1).")]
		public FsmBool normalized;
		[Tooltip("Event to send if the Hit Test is true.")]
		public FsmEvent hitEvent;
		[UIHint(UIHint.Variable)]
		[Tooltip("Store the result of the Hit Test in a bool variable (true/false).")]
		public FsmBool storeResult;
		[Tooltip("Repeat every frame. Useful if you want to wait for the hit test to return true.")]
		public FsmBool everyFrame;

#if !UNITY_2019_3_OR_NEWER
		// cache component
		private GUIElement guiElement;
#endif
		// remember game object cached, so we can re-cache component if it changes
		private GameObject gameObjectCached;

		public override void Reset()
		{
			gameObject = null;
			camera = null;
			screenPoint = new FsmVector3 { UseVariable = true};
			screenX = new FsmFloat { UseVariable = true};
			screenY = new FsmFloat { UseVariable = true };
			normalized = true;
			hitEvent = null;
			everyFrame = true;
		}

		public override void OnEnter()
		{
#if !UNITY_2019_3_OR_NEWER
			DoHitTest();

			if (!everyFrame.Value)
			{
				Finish();
			}
#else
            Finish();
#endif
		}

#if !UNITY_2019_3_OR_NEWER
		public override void OnUpdate()
		{
			DoHitTest();
		}

		void DoHitTest()
		{
			var go = Fsm.GetOwnerDefaultTarget(gameObject);
			if (go == null)
			{
				return;
			}

			// cache GUIElement component

			if (go != gameObjectCached)
			{
				guiElement = go.GetComponent<GUITexture>() ?? (GUIElement) go.GetComponent<GUIText>();
				gameObjectCached = go;
			}

			if (guiElement == null)
			{
				Finish();
				return;
			}

			// get screen point to test

			var testPoint = screenPoint.IsNone ? new Vector3(0, 0) : screenPoint.Value;
			
			if (!screenX.IsNone)
			{
				testPoint.x = screenX.Value;
			}

			if (!screenY.IsNone)
			{
				testPoint.y = screenY.Value;
			}

			if (normalized.Value)
			{
				testPoint.x *= Screen.width;
				testPoint.y *= Screen.height;
			}

			// perform hit test

			if (guiElement.HitTest(testPoint, camera))
			{
				storeResult.Value = true;
				Fsm.Event(hitEvent);
			}
			else
			{
				storeResult.Value = false;
			}
		}
#endif
	}
}