using System.Collections;
using System.Collections.Generic;
using DG.Tweening;
using Ichni;
using TMPro;
using UnityEngine;
using UnityEngine.InputSystem;

[RequireComponent(typeof(MeshFilter), typeof(MeshRenderer))]
public class SimpleGridController : MonoBehaviour
{
    public Camera targetCamera => EditorManager.instance.cameraManager.currentCamera;

    [Header("Settings")]
    public Material gridMaterial;
    public GameObject textPrefab; // 预制体需要挂载 TextMeshPro
    public Transform textParent;

    [Header("Grid Logic")]
    public bool showCoordinates = true;
    public float baseGridSize = 1.0f;
    [Range(10f, 1000f)] public float drawDistance = 100f;


    // --- 内部状态 ---
    private MeshRenderer _renderer;
    private Material _instancedMat;
    private float _currentSpacing = 1.0f;

    void Start()
    {

        InitMesh();

        _renderer = GetComponent<MeshRenderer>();
        if (gridMaterial)
        {
            _instancedMat = new Material(gridMaterial);
            _renderer.material = _instancedMat;
        }


    }










    public Color MainColor = new Color(0.8f, 0.8f, 0.8f, 0.5f);
    public Color SubColor = new Color(0.5f, 0.5f, 0.5f, 0.5f);
    void Update()
    {
        if (Mouse.current.middleButton.wasPressedThisFrame)
        {
            StartCoroutine(Pressing());
        }
    }
    GameObject coordTextObj = null;

    [System.Obsolete]
    IEnumerator Pressing()
    {
        if (coordTextObj != null)
        {
            coordTextObj.transform.DOComplete();
        }
        TextMeshPro coordText = null;
        float targetScale = 1f;
        Tweener scaleTween = null;
        while (Mouse.current.middleButton.isPressed)
        {
            Ray ray = targetCamera.ScreenPointToRay(Mouse.current.position.ReadValue());
            Plane plane = new Plane(Vector3.up, Vector3.zero);
            if (plane.Raycast(ray, out float enter))
            {
                Vector3 hitPoint = ray.GetPoint(enter);
                Vector2 xz = new Vector2(hitPoint.x, hitPoint.z);
                // 创建或复用文字对象
                if (coordTextObj == null)
                {
                    coordTextObj = Instantiate(textPrefab, textParent);
                    coordText = coordTextObj.GetComponent<TextMeshPro>();
                    coordTextObj.transform.localScale = Vector3.zero;
                    targetScale = Mathf.Clamp(Vector3.Distance(targetCamera.transform.position, hitPoint) * 0.05f, 0.1f, 1000f);
                    scaleTween = coordTextObj.transform.DOScale(Vector3.one * targetScale, 0.2f).SetEase(Ease.OutBack);
                }
                else
                {
                    // 动态融合：用DOTween的ChangeEndValue实时调整目标scale
                    targetScale = Mathf.Clamp(Vector3.Distance(targetCamera.transform.position, hitPoint) * 0.05f, 0.1f, 1000f);
                    if (scaleTween != null && scaleTween.IsActive())
                    {
                        scaleTween.ChangeEndValue(Vector3.one * targetScale, true);
                    }
                    else
                    {
                        coordTextObj.transform.localScale = Vector3.one * targetScale;
                    }
                }
                coordTextObj.transform.position = hitPoint + Vector3.up * targetScale;
                coordTextObj.transform.rotation = Quaternion.LookRotation(coordTextObj.transform.position - targetCamera.transform.position, Vector3.up);
                if (coordText == null) coordText = coordTextObj.GetComponent<TextMeshPro>();
                coordText.text = $"({xz.x:F2}, {xz.y:F2})\n({Mathf.Round(xz.x):F2}, {Mathf.Round(xz.y):F2})";
                coordText.fontSize = 8;
                coordText.enableWordWrapping = false;
                coordText.color = Color.yellow;
            }
            yield return null;
        }
        // 释放文字对象
        if (coordTextObj != null)
        {
            coordTextObj.transform.DOScale(0, 0.3f).SetEase(Ease.OutExpo).OnComplete(() =>
            {
                Destroy(coordTextObj);
                coordTextObj = null;
            });
        }
    }
    void LateUpdate()
    {
        if (!targetCamera) return;

        Vector3 camPos = targetCamera.transform.position;

        // 1. 网格跟随相机 (无限大地板)
        transform.position = new Vector3(camPos.x, 0, camPos.z);

        // 2. 计算层级 (1m / 10m / 100m)
        float absH = Mathf.Abs(camPos.y);
        float step = baseGridSize;
        Color Mcolor = MainColor;
        Color Scolor = SubColor;
        // 简单的自适应逻辑：根据高度决定网格密度
        if (absH > 150f)//>150
        {
            step *= 10f;
            Scolor = Lerp(SubColor, Color.clear, (absH - 150f) / 150f);
        }
        else if (absH > 15f)//15-150
        {
            step *= 10f;
            Mcolor = Lerp(MainColor, SubColor, (absH - 15f) / (150f - 15f));
            Scolor = Lerp(SubColor, Color.clear, (absH - 15f) / (150f - 15f));
        }
        else//0-15
        {
            Mcolor = Lerp(MainColor, SubColor, absH / 15f);
            Scolor = Lerp(SubColor, Color.clear, absH / 15f);
        }


        _currentSpacing = step;

        // 3. 更新 Shader
        if (_instancedMat)
        {
            _instancedMat.SetColor("_MainColor", Scolor);
            _instancedMat.SetColor("_AxisColor", Mcolor);
            _instancedMat.SetFloat("_GridSpacing", _currentSpacing);
            _instancedMat.SetFloat("_FadeDist", drawDistance);
        }


    }
    private Color Lerp(Color a, Color b, float t)
    {
        return new Color(
            Mathf.Lerp(a.r, b.r, t),
            Mathf.Lerp(a.g, b.g, t),
            Mathf.Lerp(a.b, b.b, t),
            Mathf.Lerp(a.a, b.a, t)
        );
    }


    private void InitMesh()
    {
        MeshFilter mf = GetComponent<MeshFilter>();
        Mesh mesh = new Mesh();
        // 覆盖视野的大 Quad
        float size = 2000f;
        Vector3[] vertices = new Vector3[4]
        {
            new Vector3(-size, 0, -size), new Vector3(size, 0, -size),
            new Vector3(-size, 0, size), new Vector3(size, 0, size)
        };
        mesh.vertices = vertices;
        mesh.triangles = new int[6] { 0, 2, 1, 2, 3, 1 };
        mesh.uv = new Vector2[4] { Vector2.zero, Vector2.right, Vector2.up, Vector2.one };
        mesh.RecalculateBounds();
        mf.mesh = mesh;
    }
}