using UnityEngine;

public class ScreenBorderToWorld : MonoBehaviour
{
    [Header("四个空对象（顺序：上、下、左、右）")]
    public Transform topPoint;
    public Transform bottomPoint;
    public Transform leftPoint;
    public Transform rightPoint;

    [Header("四个特效（顺序：上、下、左、右）")]
    public GameObject topFX;
    public GameObject bottomFX;
    public GameObject leftFX;
    public GameObject rightFX;

    [Header("目标相机（不填默认主相机）")]
    public Camera cam;

    private void Start()
    {
        if (cam == null) cam = Camera.main;

        // 上
        SetPos(topPoint, topFX, new Vector2(0.5f, 1f));

        // 下
        SetPos(bottomPoint, bottomFX, new Vector2(0.5f, 0f));

        // 左
        SetPos(leftPoint, leftFX, new Vector2(0f, 0.5f));

        // 右
        SetPos(rightPoint, rightFX, new Vector2(1f, 0.5f));
    }

    /// <summary>
    /// 归一化屏幕坐标 → 世界坐标 → 设置空对象与特效
    /// </summary>
    private void SetPos(Transform point, GameObject fx, Vector2 normalizedPos)
    {
        // 1. 归一化坐标 → 屏幕像素坐标
        float px = normalizedPos.x * Screen.width;
        float py = normalizedPos.y * Screen.height;

        Vector3 screenPos = new Vector3(px, py, 0);

        // 2. 使用你已有的转换类
        Vector3 worldPos = CoordinateTransformation.ScreenToWord(screenPos);

        // 3. 设置空对象位置
        if (point != null)
            point.position = worldPos;

        // 4. 设置特效位置
        if (fx != null)
            fx.transform.position = worldPos;
        Vector3 v3 = fx.transform.transform.position;
        v3.z = 0;
        fx.transform.position = v3;
    }
}