using System.Collections;
using System.Collections.Generic;
using System.IO;
using System.Threading.Tasks;
using UnityEngine;
using UnityEngine.AddressableAssets;
using UnityEngine.ResourceManagement.AsyncOperations;

public class MonsterMoveLine
{
    public static Dictionary<string, BezierCurveData> dic_BezierCurveDatas=new Dictionary<string, BezierCurveData>();
    public static List<BezierCurveData> curves = new List<BezierCurveData>();
    public class BezierCurveData
    {
        public string name;
        public Vector2 start;
        public List<Vector2> controlPoints = new List<Vector2>();
        public Vector2 end;
    }



    /// <summary>
    /// 读取数据 游戏开始时在awake调用aa包
    /// </summary>
    /// <param name="path"></param>
    /// <returns></returns>
    public static async Task LoadBezierTxtAsync(string path)
    {
        AsyncOperationHandle<TextAsset> handle = Addressables.LoadAssetAsync<TextAsset>(path);
        await handle.Task;
        var lines = handle.Result.text.Split('\n');
        

        foreach (var line in lines)
        {
            if (string.IsNullOrWhiteSpace(line)) continue;

            var parts = line.Split(';');
            BezierCurveData curve = new BezierCurveData();

            // 第一个是曲线名
            curve.name = parts[0];

            // 后面所有都是点
            List<Vector2> points = new List<Vector2>();
            for (int i = 1; i < parts.Length; i++)
            {
                points.Add(ParseVector(parts[i]));
            }

            // 第一个点是 start
            curve.start = points[0];

            // 最后一个点是 end
            curve.end = points[points.Count - 1];

            // 中间的都是 controlPoints
            for (int i = 1; i < points.Count - 1; i++)
            {
                curve.controlPoints.Add(points[i]);
            }

            curves.Add(curve);
            dic_BezierCurveDatas.Add(curve.name,curve);
        }

        
    }

    private static Vector2 ParseVector(string s)
    {
        var xy = s.Split(',');
        return new Vector2(float.Parse(xy[0]), float.Parse(xy[1]));
    }


    public BezierCurveData bezierCurveData;
    public float moveTime;
    public float moveSpeed;

    public void Init(BezierCurveData bezierCurveData, float Time)
    {
        this.bezierCurveData = bezierCurveData;
        this.moveTime = Time;
    }
    public Vector2 GetBezierPoint(float t)
    {
        t = t / moveTime;
        BezierCurveData curve=bezierCurveData;
        List<Vector2> points = new List<Vector2>();
        points.Add(curve.start);
        points.AddRange(curve.controlPoints);
        points.Add(curve.end);

        return DeCasteljau(points, t%1);
    }
    
    private Vector2 DeCasteljau(List<Vector2> points, float t)
    {
        while (points.Count > 1)
        {
            List<Vector2> next = new List<Vector2>();
            for (int i = 0; i < points.Count - 1; i++)
            {
                next.Add(Vector2.Lerp(points[i], points[i + 1], t));
            }
            points = next;
        }
        return CanvasToWorld( points[0],UIManager.Instance.uiRoot.GetComponent<RectTransform>(),Camera.main);
    }
    public static Vector3 CanvasToWorld(Vector2 canvasPos, RectTransform canvas, Camera cam)
    {
        // 1. 获取 Canvas 实际像素尺寸（自动适配所有设备）
        float canvasWidth = canvas.rect.width;
        float canvasHeight = canvas.rect.height;

        // 2. 正交相机的世界高度
        float worldHeight = cam.orthographicSize * 2f;

        // 3. 世界宽度 = 世界高度 * 屏幕宽高比
        float worldWidth = worldHeight * cam.aspect;

        // 4. 画布单位 → 世界单位比例（横竖一致）
        float scaleX = worldWidth / canvasWidth;
        float scaleY = worldHeight / canvasHeight;

        // 5. 你的 canvasPos 是以中心为原点的坐标
        float worldX = canvasPos.x * scaleX;
        float worldY = canvasPos.y * scaleY;

        // 6. 映射到世界 z = 0 平面
        return new Vector3(worldX, worldY, 0f);
    }

    public static Vector2 AnchoredPos_ToCanvas(RectTransform target, Canvas canvas)
    {
        // 1. 先把 anchoredPosition（父坐标）转换成世界坐标
        Vector3 worldPos = target.TransformPoint(target.anchoredPosition);

        // 2. 再把世界坐标转换成 Canvas 的局部坐标（等价于 Canvas 下的 anchoredPosition）
        RectTransform canvasRT = canvas.GetComponent<RectTransform>();

        Vector2 canvasLocalPos;
        RectTransformUtility.ScreenPointToLocalPointInRectangle(
            canvasRT,
            RectTransformUtility.WorldToScreenPoint(canvas.worldCamera, worldPos),
            canvas.renderMode == RenderMode.ScreenSpaceOverlay ? null : canvas.worldCamera,
            out canvasLocalPos
        );

        return canvasLocalPos;
    }


}