using UnityEngine;
using System.Collections;
using System.Collections.Generic;

public class LineShowModel : MonoBehaviour
{
    public enum DrawingState
    {
        Idle,           // 空闲状态
        SelectingStart, // 选择起点
        SelectingEnd    // 选择终点
    }

    [Header("连线设置")]
    public Material wireMaterial;
    public Color wireColor = Color.red;
    public float wireWidth = 0.02f;

    [Header("吸附设置")]
    public bool enableSnapping = true;           // 启用吸附功能
    public float snapDistance = 1.0f;            // 吸附距离
    public LayerMask snapLayers = -1;            // 可吸附的层
    public bool snapToColliderCenter = true;     // 吸附到碰撞体中心
    public Color snapHighlightColor = Color.cyan; // 吸附高亮颜色

    [Header("圆柱体连线设置")]
    public bool useCylinderWire = true; // 启用圆柱体连线
    public Material cylinderWireMaterial;
    public float cylinderWireDiameter = 0.02f;
    public int cylinderSegments = 8; // 圆柱体面数，影响性能

    [Header("预览设置")]
    public Material previewMaterial; // 预览线材质
    public Color previewColor = new Color(1, 1, 1, 0.5f); // 预览线颜色（半透明）
    public float previewWireDiameter = 0.015f; // 预览线直径

    [Header("删除设置")]
    public KeyCode deleteKey = KeyCode.Mouse2; // 默认为鼠标右键
    public float deleteDetectionRadius = 0.5f; // 删除检测半径

    [Header("状态显示")]
    public DrawingState currentState = DrawingState.Idle;

    // 连线数据
    private Vector3 startPoint;
    private Vector3 endPoint;
    private GameObject currentWireObject;
    private GameObject previewWireObject; // 预览连线对象

    // 吸附相关
    private GameObject snapTarget;           // 当前吸附目标
    private Renderer snapTargetRenderer;     // 吸附目标的渲染器
    private Color snapTargetOriginalColor;   // 吸附目标原始颜色
    private bool isSnapTargetHighlighted = false;

    // 存储所有已创建的连线
    private List<GameObject> allWires = new List<GameObject>();

    // 起点和终点的碰撞体
    private GameObject startColliderObject;
    private GameObject endColliderObject;

    // 单例模式，便于外部调用
    public static LineShowModel Instance { get; private set; }

    void Awake()
    {
        // 设置单例
        if (Instance == null)
        {
            Instance = this;
        }
        else
        {
            Destroy(gameObject);
        }
    }

    void Update()
    {
        HandleInput();

        if (currentState == DrawingState.SelectingEnd)
        {
            UpdateWirePreview();
        }

        // 在选择终点状态时检查吸附
        if (currentState == DrawingState.SelectingEnd && enableSnapping)
        {
            CheckForSnapTargets();
        }
        else
        {
            ClearSnapHighlight();
        }
    }

    void HandleInput()
    {
        if (Input.GetMouseButtonDown(0)) // 左键点击
        {
            HandleMouseClick();
        }

        if (Input.GetKeyDown(KeyCode.Escape)) // 取消当前操作
        {
            CancelDrawing();
        }

        if (Input.GetKeyDown(deleteKey)) // 删除操作
        {
            HandleDelete();
        }
    }

    void HandleMouseClick()
    {
        Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
        RaycastHit hit;

        // 首先检查是否有吸附目标
        if (snapTarget != null)
        {
            HandleSnapTargetClick();
        }
        else if (Physics.Raycast(ray, out hit, Mathf.Infinity, snapLayers))
        {
            HandleColliderClick(hit.collider.gameObject, hit.point);
        }
        else
        {
            // 如果没有击中任何物体，且不在选择起点状态，则忽略
            if (currentState == DrawingState.Idle)
            {
                Debug.Log("请点击一个碰撞体作为连线起点");
            }
        }
    }

    void HandleSnapTargetClick()
    {
        if (snapTarget == null) return;

        switch (currentState)
        {
            case DrawingState.Idle:
                // 选择起点
                StartNewWire(snapTarget);
                break;

            case DrawingState.SelectingEnd:
                // 选择终点
                CompleteWire(snapTarget);
                break;
        }
    }

    void HandleColliderClick(GameObject colliderObject, Vector3 hitPoint)
    {
        switch (currentState)
        {
            case DrawingState.Idle:
                // 选择起点
                StartNewWire(colliderObject);
                break;

            case DrawingState.SelectingEnd:
                // 选择终点
                CompleteWire(colliderObject);
                break;
        }
    }

    void StartNewWire(GameObject startCollider)
    {
        if (startCollider == null) return;

        startColliderObject = startCollider;
        startPoint = GetObjectCenter(startCollider);
        currentState = DrawingState.SelectingEnd;

        // 创建预览连线
        CreatePreviewWire();

        // 高亮起点碰撞体
        HighlightObject(startCollider);

        Debug.Log($"选择起点: {startCollider.name}");
    }

    void CompleteWire(GameObject endCollider)
    {
        if (endCollider == null || startColliderObject == null) return;

        // 检查是否连接到自身
        if (endCollider == startColliderObject)
        {
            Debug.LogWarning("不能连接到自身！");
            CancelDrawing();
            return;
        }

        endColliderObject = endCollider;
        endPoint = GetObjectCenter(endCollider);

        // 创建最终的连线
        GameObject newWire = CreateFinalWire();

        currentState = DrawingState.Idle;

        // 清除预览和高亮
        ClearPreviewWire();
        ClearSnapHighlight();

        Debug.Log($"选择终点: {endCollider.name}, 连线完成");

        // 返回新创建的连线对象，供外部使用
        OnWireCreated?.Invoke(newWire, startColliderObject, endColliderObject);
    }

    void CreatePreviewWire()
    {
        // 清除之前的预览
        ClearPreviewWire();

        previewWireObject = new GameObject("PreviewWire");

        if (useCylinderWire)
        {
            CreateCylinderPreviewWire();
        }
        else
        {
            CreateLineRendererPreviewWire();
        }
    }

    void CreateCylinderPreviewWire()
    {
        // 创建预览圆柱体
        GameObject cylinder = GameObject.CreatePrimitive(PrimitiveType.Cylinder);
        cylinder.name = "PreviewCylinder";
        cylinder.transform.SetParent(previewWireObject.transform);

        // 设置预览材质
        Renderer renderer = cylinder.GetComponent<Renderer>();
        if (previewMaterial != null)
        {
            renderer.material = previewMaterial;
        }
        else
        {
            // 创建默认预览材质
            Material defaultPreviewMaterial = new Material(Shader.Find("Standard"));
            defaultPreviewMaterial.color = previewColor;
            renderer.material = defaultPreviewMaterial;
        }

        // 初始位置和缩放
        cylinder.transform.position = startPoint;
        cylinder.transform.localScale = new Vector3(
            previewWireDiameter,
            0.001f, // 初始高度很小
            previewWireDiameter
        );

        // 移除碰撞器，避免干扰
        Destroy(cylinder.GetComponent<Collider>());
    }

    void CreateLineRendererPreviewWire()
    {
        // 使用LineRenderer作为备选预览
        LineRenderer lr = previewWireObject.AddComponent<LineRenderer>();
        lr.positionCount = 2;
        lr.SetPosition(0, startPoint);
        lr.SetPosition(1, startPoint);

        // 配置LineRenderer
        if (previewMaterial != null)
        {
            lr.material = previewMaterial;
        }
        else
        {
            lr.material = new Material(Shader.Find("Sprites/Default"));
        }

        lr.startColor = previewColor;
        lr.endColor = previewColor;
        lr.startWidth = previewWireDiameter;
        lr.endWidth = previewWireDiameter;
        lr.useWorldSpace = true;
    }

    void UpdateWirePreview()
    {
        if (currentState == DrawingState.SelectingEnd && previewWireObject != null)
        {
            Vector3 targetPoint;

            if (snapTarget != null)
            {
                targetPoint = GetObjectCenter(snapTarget);
            }
            else
            {
                targetPoint = GetMouseWorldPosition();
            }

            if (useCylinderWire)
            {
                UpdateCylinderPreviewWire(startPoint, targetPoint);
            }
            else
            {
                UpdateLineRendererPreviewWire(startPoint, targetPoint);
            }
        }
    }

    void UpdateCylinderPreviewWire(Vector3 start, Vector3 end)
    {
        Transform cylinderTransform = previewWireObject.transform.Find("PreviewCylinder");
        if (cylinderTransform == null) return;

        GameObject cylinder = cylinderTransform.gameObject;

        // 计算连线的方向、长度和中点
        Vector3 direction = end - start;
        float distance = direction.magnitude;

        if (distance < 0.001f)
        {
            // 距离太短，隐藏圆柱体
            cylinder.transform.localScale = new Vector3(previewWireDiameter, 0.001f, previewWireDiameter);
            return;
        }

        Vector3 midPoint = (start + end) / 2f;

        // 设置圆柱体的位置和旋转
        cylinder.transform.position = midPoint;
        cylinder.transform.up = direction.normalized;

        // 设置圆柱体的缩放
        cylinder.transform.localScale = new Vector3(
            previewWireDiameter,
            distance / 2f,
            previewWireDiameter
        );
    }

    void UpdateLineRendererPreviewWire(Vector3 start, Vector3 end)
    {
        LineRenderer lr = previewWireObject.GetComponent<LineRenderer>();
        if (lr != null)
        {
            lr.SetPosition(0, start);
            lr.SetPosition(1, end);
        }
    }

    GameObject CreateFinalWire()
    {
        if (startColliderObject == null || endColliderObject == null) return null;

        GameObject wireObject = new GameObject($"Wire_{System.DateTime.Now:yyyyMMddHHmmss}");

        if (useCylinderWire)
        {
            CreateCylinderWire(wireObject, startPoint, endPoint);
        }
        else
        {
            CreateLineRendererWire(wireObject, startPoint, endPoint);
        }

        // 添加连线数据组件
        LineShowModelCylinderWireData wireData = wireObject.AddComponent<LineShowModelCylinderWireData>();
        wireData.startPoint = startPoint;
        wireData.endPoint = endPoint;
        wireData.startCollider = startColliderObject;
        wireData.endCollider = endColliderObject;
        wireData.wireDiameter = cylinderWireDiameter;
        wireData.creationTime = System.DateTime.Now;

        // 添加到连线列表
        allWires.Add(wireObject);
        StartCoroutine(LineManager.instance.Checkconnection(startColliderObject.transform, endColliderObject.transform));
        // 重置起点和终点
        startColliderObject = null;
        endColliderObject = null;

        return wireObject;
    }

    void CreateCylinderWire(GameObject wireObject, Vector3 start, Vector3 end)
    {
        GameObject cylinder = GameObject.CreatePrimitive(PrimitiveType.Cylinder);
        cylinder.name = "WireCylinder";
        cylinder.transform.SetParent(wireObject.transform);

        // 设置材质
        if (cylinderWireMaterial != null)
        {
            Renderer renderer = cylinder.GetComponent<Renderer>();
            renderer.material = cylinderWireMaterial;
        }
        else if (wireMaterial != null)
        {
            Renderer renderer = cylinder.GetComponent<Renderer>();
            renderer.material = wireMaterial;
        }

        // 计算连线的方向、长度和中点
        Vector3 direction = end - start;
        float distance = direction.magnitude;
        Vector3 midPoint = (start + end) / 2f;

        // 设置圆柱体的位置和旋转
        cylinder.transform.position = midPoint;
        cylinder.transform.up = direction.normalized;

        // 设置圆柱体的缩放
        cylinder.transform.localScale = new Vector3(
            cylinderWireDiameter,
            distance / 2f,
            cylinderWireDiameter
        );

        // 可选：添加碰撞器
        if (cylinder.GetComponent<Collider>() != null)
        {
            Destroy(cylinder.GetComponent<Collider>());
        }
    }

    void CreateLineRendererWire(GameObject wireObject, Vector3 start, Vector3 end)
    {
        LineRenderer lr = wireObject.AddComponent<LineRenderer>();
        lr.positionCount = 2;
        lr.SetPosition(0, start);
        lr.SetPosition(1, end);

        // 配置LineRenderer
        if (wireMaterial != null)
        {
            lr.material = wireMaterial;
        }
        else
        {
            lr.material = new Material(Shader.Find("Sprites/Default"));
        }

        lr.startColor = wireColor;
        lr.endColor = wireColor;
        lr.startWidth = wireWidth;
        lr.endWidth = wireWidth;
        lr.useWorldSpace = true;
    }

    void ClearPreviewWire()
    {
        if (previewWireObject != null)
        {
            Destroy(previewWireObject);
            previewWireObject = null;
        }
    }

    void CheckForSnapTargets()
    {
        Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
        RaycastHit hit;

        // 清除之前的吸附高亮
        ClearSnapHighlight();

        // 检查鼠标位置附近是否有可吸附的物体
        if (Physics.Raycast(ray, out hit, Mathf.Infinity, snapLayers))
        {
            GameObject hitObject = hit.collider.gameObject;

            // 跳过起点碰撞体
            if (hitObject == startColliderObject)
            {
                return;
            }

            // 计算鼠标位置与物体中心的距离
            Vector3 objectCenter = GetObjectCenter(hitObject);
            float distance = Vector3.Distance(GetMouseWorldPosition(), objectCenter);

            if (distance <= snapDistance)
            {
                // 设置吸附目标
                snapTarget = hitObject;

                // 高亮显示可吸附的物体
                HighlightSnapTarget(snapTarget);
            }
        }
    }

    Vector3 GetObjectCenter(GameObject obj)
    {
        if (obj == null) return Vector3.zero;

        if (snapToColliderCenter)
        {
            Collider collider = obj.GetComponent<Collider>();
            if (collider != null)
            {
                return collider.bounds.center;
            }
        }

        // 默认使用变换位置
        return obj.transform.position;
    }

    void HighlightSnapTarget(GameObject target)
    {
        if (target == null) return;

        snapTargetRenderer = target.GetComponent<Renderer>();
        if (snapTargetRenderer != null)
        {
            // 记录原始颜色
            snapTargetOriginalColor = snapTargetRenderer.material.color;

            // 设置高亮颜色
            snapTargetRenderer.material.color = snapHighlightColor;
            isSnapTargetHighlighted = true;
        }
    }

    void HighlightObject(GameObject obj)
    {
        if (obj == null) return;

        Renderer renderer = obj.GetComponent<Renderer>();
        if (renderer != null)
        {
            // 临时高亮物体
            Color originalColor = renderer.material.color;
            renderer.material.color = Color.green;

            // 可以在这里添加一个协程来在一段时间后恢复颜色
            StartCoroutine(RestoreColorAfterDelay(renderer, originalColor, 1.0f));
        }
    }

    IEnumerator RestoreColorAfterDelay(Renderer renderer, Color originalColor, float delay)
    {
        yield return new WaitForSeconds(delay);

        if (renderer != null)
        {
            renderer.material.color = originalColor;
        }
    }

    void ClearSnapHighlight()
    {
        if (snapTargetRenderer != null && isSnapTargetHighlighted)
        {
            snapTargetRenderer.material.color = snapTargetOriginalColor;
            snapTargetRenderer = null;
            isSnapTargetHighlighted = false;
        }
        snapTarget = null;
    }

    public void CancelDrawing()
    {
        ClearPreviewWire();
        ClearSnapHighlight();
        currentState = DrawingState.Idle;

        // 重置起点和终点
        startColliderObject = null;
        endColliderObject = null;

        Debug.Log("取消连线操作");
    }

    Vector3 GetMouseWorldPosition()
    {
        Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
        RaycastHit hit;

        // 优先使用吸附目标的位置
        if (snapTarget != null)
        {
            return GetObjectCenter(snapTarget);
        }

        // 其次使用射线击中的位置
        if (Physics.Raycast(ray, out hit, Mathf.Infinity, snapLayers))
        {
            return hit.point;
        }

        // 如果没有击中任何物体，使用默认平面
        Plane defaultPlane = new Plane(Vector3.up, Vector3.zero);
        float enter;
        if (defaultPlane.Raycast(ray, out enter))
        {
            return ray.GetPoint(enter);
        }

        // 最后使用射线上的一个点
        return ray.origin + ray.direction * 10f;
    }

    // 公共方法：开始新连线
    public void StartNewWire()
    {
        if (currentState != DrawingState.Idle)
        {
            CancelDrawing();
        }
        currentState = DrawingState.SelectingStart;
    }

    // 公共方法：删除所有连线
    public void ClearAllWires()
    {
        foreach (GameObject wire in allWires)
        {
            if (wire != null)
                Destroy(wire);
        }
        allWires.Clear();
        Debug.Log("已清除所有连线");

        // 触发事件
        OnAllWiresDeleted?.Invoke();
    }

    // 公共方法：删除最后一个连线
    public void DeleteLastWire()
    {
        if (allWires.Count > 0)
        {
            GameObject lastWire = allWires[allWires.Count - 1];
            DeleteWire(lastWire);
        }
        else
        {
            Debug.Log("没有可删除的连线");
        }
    }

    // 公共方法：删除指定连线
    public void DeleteWire(GameObject wireObject)
    {
        if (wireObject == null) return;

        // 获取连线数据
        LineShowModelCylinderWireData wireData = wireObject.GetComponent<LineShowModelCylinderWireData>();
        GameObject startCollider = wireData?.startCollider;
        GameObject endCollider = wireData?.endCollider;

        // 从列表中移除
        allWires.Remove(wireObject);

        // 销毁连线对象
        Destroy(wireObject);

        Debug.Log($"删除连线: {wireObject.name}");

        // 触发事件
        OnWireDeleted?.Invoke(wireObject, startCollider, endCollider);
    }

    // 公共方法：根据碰撞体删除连线
    public void DeleteWiresByCollider(GameObject colliderObject)
    {
        List<GameObject> wiresToDelete = new List<GameObject>();

        // 查找所有连接到该碰撞体的连线
        foreach (GameObject wire in allWires)
        {
            LineShowModelCylinderWireData wireData = wire?.GetComponent<LineShowModelCylinderWireData>();
            if (wireData != null && (wireData.startCollider == colliderObject || wireData.endCollider == colliderObject))
            {
                wiresToDelete.Add(wire);
            }
        }

        // 删除找到的连线
        foreach (GameObject wire in wiresToDelete)
        {
            DeleteWire(wire);
        }

        if (wiresToDelete.Count > 0)
        {
            Debug.Log($"删除了 {wiresToDelete.Count} 条连接到 {colliderObject.name} 的连线");
        }
    }

    // 公共方法：根据两个碰撞体删除特定连线
    public void DeleteWireByColliders(GameObject startCollider, GameObject endCollider)
    {
        foreach (GameObject wire in allWires)
        {
            LineShowModelCylinderWireData wireData = wire?.GetComponent<LineShowModelCylinderWireData>();
            if (wireData != null &&
                ((wireData.startCollider == startCollider && wireData.endCollider == endCollider) ||
                 (wireData.startCollider == endCollider && wireData.endCollider == startCollider)))
            {
                DeleteWire(wire);
                Debug.Log($"删除了 {startCollider.name} 和 {endCollider.name} 之间的连线");
                return;
            }
        }

        Debug.Log($"未找到 {startCollider.name} 和 {endCollider.name} 之间的连线");
    }

    // 公共方法：设置吸附目标（用于编程控制）
    public void SetSnapTarget(GameObject target)
    {
        if (enableSnapping && target != null)
        {
            snapTarget = target;
            HighlightSnapTarget(target);
        }
    }

    // 公共方法：清除吸附目标
    public void ClearSnapTarget()
    {
        ClearSnapHighlight();
    }

    // 公共方法：检查物体是否可以吸附
    public bool CanSnapToObject(GameObject obj)
    {
        if (obj == null) return false;

        // 检查物体是否在可吸附层
        if (((1 << obj.layer) & snapLayers) == 0) return false;

        // 检查物体是否有碰撞体
        Collider collider = obj.GetComponent<Collider>();
        if (collider == null) return false;

        return true;
    }

    // 公共方法：获取所有连线
    public List<GameObject> GetAllWires()
    {
        return new List<GameObject>(allWires);
    }

    // 公共方法：获取连接到特定碰撞体的所有连线
    public List<GameObject> GetWiresByCollider(GameObject colliderObject)
    {
        List<GameObject> connectedWires = new List<GameObject>();

        foreach (GameObject wire in allWires)
        {
            LineShowModelCylinderWireData wireData = wire?.GetComponent<LineShowModelCylinderWireData>();
            if (wireData != null && (wireData.startCollider == colliderObject || wireData.endCollider == colliderObject))
            {
                connectedWires.Add(wire);
            }
        }

        return connectedWires;
    }

    // 公共方法：检查两个碰撞体之间是否有连线
    public bool AreCollidersConnected(GameObject collider1, GameObject collider2)
    {
        foreach (GameObject wire in allWires)
        {
            LineShowModelCylinderWireData wireData = wire?.GetComponent<LineShowModelCylinderWireData>();
            if (wireData != null &&
                ((wireData.startCollider == collider1 && wireData.endCollider == collider2) ||
                 (wireData.startCollider == collider2 && wireData.endCollider == collider1)))
            {
                return true;
            }
        }

        return false;
    }

    // 处理删除操作
    void HandleDelete()
    {
        // 如果正在绘制连线，先取消绘制
        if (currentState != DrawingState.Idle)
        {
            CancelDrawing();
            return;
        }

        // 查找鼠标位置附近的连线
        Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
        RaycastHit hit;

        if (Physics.Raycast(ray, out hit, Mathf.Infinity))
        {
            GameObject hitObject = hit.collider.gameObject;

            // 检查是否点击到了连线
            if (IsWire(hitObject))
            {
                DeleteWire(hitObject);
                return;
            }

            // 检查是否是连线的子物体
            if (hitObject.transform.parent != null)
            {
                GameObject parent = hitObject.transform.parent.gameObject;
                if (IsWire(parent))
                {
                    DeleteWire(parent);
                    return;
                }
            }
        }

        // 如果没有找到可删除的对象，尝试删除最后一个连线
        DeleteLastWire();
    }

    // 检查对象是否是连线
    bool IsWire(GameObject obj)
    {
        if (obj == null) return false;

        // 检查是否是连线
        if (obj.name.StartsWith("Wire_") || obj.GetComponent<LineShowModelCylinderWireData>() != null)
        {
            return true;
        }

        return false;
    }

    // 事件定义
    public delegate void WireCreatedHandler(GameObject wire, GameObject startCollider, GameObject endCollider);
    public delegate void WireDeletedHandler(GameObject wire, GameObject startCollider, GameObject endCollider);
    public delegate void AllWiresDeletedHandler();

    // 事件
    public static event WireCreatedHandler OnWireCreated;
    public static event WireDeletedHandler OnWireDeleted;
    public static event AllWiresDeletedHandler OnAllWiresDeleted;
}