using UnityEngine;
using UnityEngine.UI;

public class LineBetweenObjects : MonoBehaviour
{
    [SerializeField] RectTransform start;
    [SerializeField] RectTransform end;
    [SerializeField] Image lineImg;

    public void SetStart(RectTransform start) => this.start = start;
    public void SetEnd(RectTransform end) => this.end = end;

    private void OnEnable()
    {
        lineImg?.gameObject.SetActive(true);
    }

    private void OnDisable()
    {
        lineImg?.gameObject.SetActive(false);
    }

    private void Start()
    {
        lineImg.rectTransform.pivot = new Vector2(0.5f, 0.5f);
        lineImg.rectTransform.anchorMin = new Vector2(0.5f, 0.5f);
        lineImg.rectTransform.anchorMax = new Vector2(0.5f, 0.5f);
    }

    private void LateUpdate()
    {
        Vector2 lineCenterPos = Vector2.Lerp(start.anchoredPosition, end.anchoredPosition, 0.5f);
        float lineLength = Vector2.Distance(start.anchoredPosition, end.anchoredPosition);

        Vector2 diff = end.anchoredPosition - start.anchoredPosition;
        float angle = Mathf.Atan2(diff.y, diff.x) * Mathf.Rad2Deg;

        lineImg.rectTransform.sizeDelta = new Vector2(lineLength, lineImg.rectTransform.sizeDelta.y);
        lineImg.rectTransform.anchoredPosition = lineCenterPos;
        lineImg.rectTransform.localEulerAngles = new Vector3(0, 0, angle);
    }
}