using System.Collections;
using System.Collections.Generic;
using UnityEngine;

//[ExecuteInEditMode]
[DisallowMultipleComponent]
[RequireComponent(typeof(TopDownTransform))]
[RequireComponent(typeof(SpriteRenderer))]
public class TopDownShadowCaster : MonoBehaviour
{
	[SerializeField] private Color m_Color = new Color32(0,0,0, 58);
	[SerializeField] private Vector2 m_Scale = new Vector2(1, 0.5f);

	private GameObject m_Shadow;
	private SpriteRenderer m_ShadowRenderer;

	private TopDownTransform m_Coord;
	private SpriteRenderer m_SpriteRenderer;

	public void Flip(bool flip)
	{
		m_ShadowRenderer.flipX = flip;
	}

	private void Awake()
	{
		m_Coord = GetComponent<TopDownTransform>();
		m_SpriteRenderer = GetComponent<SpriteRenderer>();

		// 
		for(int i = this.transform.childCount - 1; i >= 0 ; --i)
		{
			GameObject child = this.transform.GetChild(i).gameObject;
			if (child.name == "shadow")
			{
				Destroy(child);
			}
		}
		
		if (m_Shadow == null)
		{
			m_Shadow = new GameObject("shadow");
//			m_Shadow.hideFlags = HideFlags.HideAndDontSave;

			m_Shadow.transform.SetParent(transform);
			m_Shadow.transform.localScale = m_Scale;
			
			m_ShadowRenderer = m_Shadow.AddComponent<SpriteRenderer>();
			m_ShadowRenderer.color = m_Color;
			m_ShadowRenderer.sprite = m_SpriteRenderer.sprite;
			m_ShadowRenderer.sortingLayerName = "Shadow";
		}
	}

	//private void Update()
	private void LateUpdate()
	{
		m_ShadowRenderer.color = m_Color;
		m_ShadowRenderer.sprite = m_SpriteRenderer.sprite;

		SetPosition();
	}

	public void SetPosition()
	{
		Vector3 pos = m_Coord.GetProjectedGroundPosition();
		m_Shadow.transform.position = pos;
	}

}