using Sirenix.OdinInspector;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;

/// <summary>
/// 最上层UI_箭头指引
/// </summary>
public partial class TopmostLayerUI
{
    /// <summary>
    /// 边缘间隔
    /// </summary>
    public float edgeSpacing=0.5f;

    /// <summary>
    /// 箭头指引节点
    /// </summary>
    public Transform arrowheadPointToNode;

    /// <summary>
    /// 箭头指向的字典
    /// </summary>
    public Dictionary<string, ArrowPoints> arrowPointsDic = new Dictionary<string, ArrowPoints>();

    /// <summary>
    /// 设置箭头指向
    /// </summary>
    /// <param name="mono">MonoBehaviour类</param>
    /// <param name="name">指向ID</param>
    /// <param name="target">指向的3D对象</param>
    /// <param name="sprite">图标</param>
    public void SetArrowObj(string name, GameObject target, Sprite sprite = null)
    {
        if (this.arrowPointsDic.ContainsKey(name)) return;
        YooAssetManager.Instance.LoadAssetAsync<GameObject>(PackagesName.GameData, "ArrowObj", (arrowObj) =>
        {
            ArrowObjUI arrows =CachePoolManager.Instance.Take(arrowObj).GetComponent<ArrowObjUI>();
            arrows.SetIconImage(sprite);
            arrows.transform.SetParent(arrowheadPointToNode);
            arrows.transform.localPosition = Vector3.zero;
            arrows.transform.localScale = Vector3.one;  

            Coroutine coroutine = StartCoroutine(E_SetPointObj(arrows, target.transform));
            ArrowPoints arrowPoints = new ArrowPoints();
            arrowPoints.coroutine = coroutine;
            arrowPoints.arrowObj = arrows.gameObject;

            if (!arrowPointsDic.ContainsKey(name))
            {
                arrowPointsDic.Add(name, arrowPoints);
            }
        });
    }

    /// <summary>
    /// 设置箭头指向的协程
    /// </summary>
    /// <returns></returns>
    private IEnumerator E_SetPointObj(ArrowObjUI arrows, Transform target)
    {
        Vector3 recordingPos=Vector3.zero;
        arrows.gameObject.SetActive(false);
        while (true)
        {
            if (target)
            {
                var pos = Camera.main.WorldToScreenPoint(target.transform.position);
                var distance = Vector3.Distance(recordingPos, pos);
                if (distance > 1)
                {
                    recordingPos = pos;
                    if (0 > pos.x || pos.x > Screen.width || pos.y < 0 || pos.y > Screen.height || pos.z < 0)
                    {
                        arrows.gameObject.SetActive(true);

                        if (pos.z < 0)
                        {
                            pos = pos * -1;
                        }

                        var startpos = new Vector3(Screen.width / 2f, Screen.height / 2f, 0);
                        var dir = (pos - startpos).normalized;

                        //通过反余弦函数获取 向量 a、b 夹角（默认为 弧度）
                        float radians = Mathf.Atan2(dir.y, dir.x);

                        //将弧度转换为 角度
                        float angle = radians * Mathf.Rad2Deg;

                        arrows.transform.localEulerAngles = new Vector3(0, 0, angle);
        
                        float sereenangle = (float)Screen.height / (float)Screen.width;
                        var va = System.Math.Abs(dir.y / dir.x);
                        if (va <= sereenangle)
                        {
                            var length = arrows.GetComponent<RectTransform>().sizeDelta.x;
                            if (pos.x < 0)
                            {
                                arrows.transform.position = GetNodeX(pos, startpos, length * edgeSpacing);
                            }
                            else
                            {
                                arrows.transform.position = GetNodeX(pos, startpos, Screen.width - length * edgeSpacing);
                            }
                        }
                        else
                        {
                            var length = arrows.GetComponent<RectTransform>().sizeDelta.x;

                            if (pos.y < 0)
                            {
                                arrows.transform.position = GetNodeY(pos, startpos, length * edgeSpacing);
                            }
                            else
                            {
                                arrows.transform.position = GetNodeY(pos, startpos, Screen.height - length * edgeSpacing);
                            }
                        }
                    }
                    else
                    {
                        arrows.gameObject.SetActive(false);
                    }
                }
            }
            yield return null;
        }
    }

    /// <summary>
    /// 计算物体超过屏幕高或小于0时UI的位置
    /// </summary>
    /// <returns></returns>
    private Vector3 GetNodeY(Vector3 pos, Vector3 startpos, float v)
    {
        pos = new Vector3(pos.x, pos.y, 0);
        Vector3 ab = pos - startpos;
        Vector3 am = ab * (Mathf.Abs(startpos.y - v) / Mathf.Abs(pos.y - startpos.y));
        Vector3 om = startpos + am;
        return om;
    }

    /// <summary>
    /// 计算物体超过屏幕宽或小于0时UI的位置
    /// </summary>
    /// <returns></returns>
    private Vector3 GetNodeX(Vector3 pos, Vector3 startpos, float v)
    {
        pos = new Vector3(pos.x, pos.y, 0);
        Vector3 ab = pos - startpos;
        Vector3 am = ab * (Mathf.Abs(startpos.x - v) / Mathf.Abs(pos.x - startpos.x));
        Vector3 om = startpos + am;
        return om;
    }

    /// <summary>
    /// 指定关闭
    /// </summary>
    /// <param name="name"></param>
    public void SpecifyClose(string name)
    {
        if (arrowPointsDic.ContainsKey(name))
        {
            StopCoroutine(arrowPointsDic[name].coroutine);
            Destroy(arrowPointsDic[name].arrowObj);
            arrowPointsDic.Remove(name);
        }
    }

    /// <summary>
    /// 全部关闭
    /// </summary>
    [Button]
    public void Clear()
    {
        foreach (var item in arrowPointsDic)
        {
            StopCoroutine(arrowPointsDic[item.Key].coroutine);
            Destroy(arrowPointsDic[item.Key].arrowObj);
        }
        arrowPointsDic.Clear();
    }
}

/// <summary>
/// 指向对象
/// </summary>
public class ArrowPoints
{
    /// <summary>
    /// 指向的协程
    /// </summary>
    public Coroutine coroutine;

    /// <summary>
    /// 指向问题的UI
    /// </summary>
    public GameObject arrowObj;
}