using System.Collections;
using System.Collections.Generic;
using TMPro;
using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.UI;

public class PlaceItem : MonoBehaviour
{

	#region PRIVATE VARIABLES

	// Reference to canvas graphic raycaster
	private GraphicRaycaster graphicRaycaster;
	// Reference to pointer event data
	private PointerEventData pointerEventData;
	// Reference to event system in scene
	private EventSystem eventSystem;

	// Reference to map
	private GameObject map;

	#endregion

	#region MONOBEHAVIOUR CALLBACKS

	private void Start()
	{
		// Find the Raycaster from the GameObject (the Canvas)
		graphicRaycaster = FindObjectOfType<GraphicRaycaster>();

		// Find the Event System from the Scene
		eventSystem = FindObjectOfType<EventSystem>();

		// Find the map game object in the scene
		map = GameObject.Find("Map");
	}

	private void Update()
	{
		if (Input.GetMouseButtonDown(0))
		{
			PlaceItemOnMap();
		}
	}

	#endregion

	#region PLACE ITEM ON MAP

	private void PlaceItemOnMap()
	{
		// Set up the new Pointer Event
		pointerEventData = new PointerEventData(eventSystem);
		// Set the Pointer Event Position to that of the mouse position
		pointerEventData.position = Input.mousePosition;

		// Create a list of Raycast Results
		List<RaycastResult> results = new List<RaycastResult>();

		// Raycast using the Graphics Raycaster and mouse click position
		graphicRaycaster.Raycast(pointerEventData, results);
		
		foreach (RaycastResult result in results)
		{
			Debug.Log(results[0].gameObject);
		}

		// For every result returned, output the name of the GameObject on the Canvas hit by the Ray (except for the item on mouse pointer)
		for (int i = 0; i < results.Count; i++)
		{
			// Check if number of results hit by the Ray is more than 0
			if (results.Count > 0)
			{
				Debug.Log(i + " : " + results[i].gameObject);
			}
		}
	}

	#endregion

}