using UnityEngine;
using UnityEngine.EventSystems;

/// <summary>
/// 召唤师对决：召唤师点地移动操控（直线移动，无寻路）。
/// 点击己方区域地面 → 直线走到目标点（clamp 在己方带内）。
/// 移动时不攻击；站定后自动攻击射程内目标。
/// </summary>
public class SummonerClickMovement : MonoBehaviour
{
    [Header("己方半场 clamp（世界坐标）")]
    public float minX = -9f;
    public float maxX = 9f;
    public float minZ = -29f;
    public float maxZ = -11f;

    [Header("移动速度")]
    public float moveSpeed = 5f;
    public float stopDistance = 0.2f;

    [Header("地面射线")]
    public LayerMask groundMask = ~0;

    private Camera mainCamera;
    private MainCharacterCombat combat;
    private Animator animator;
    private Vector3 targetPosition;
    private bool hasTarget;

    private void Awake()
    {
        combat = GetComponent<MainCharacterCombat>();
        animator = GetComponent<Animator>();
    }

    private void Start()
    {
        mainCamera = Camera.main;
    }

    private void Update()
    {
        HandleClickToMove();
        HandleMovement();
    }

    // 点地移动：点击地面即设置目标点（EventSystem 判定不在 UI 上时才生效）。
    private void HandleClickToMove()
    {
        if (Input.GetMouseButtonDown(0) && !IsPointerOverUI())
        {
            if (RaycastGround(out Vector3 groundPoint))
            {
                Vector3 clamped = ClampToOwnHalf(groundPoint);
                MoveTo(clamped);
            }
        }
    }

    // 执行直线移动
    private void HandleMovement()
    {
        if (!hasTarget) return;

        Vector3 currentPos = transform.position;
        Vector3 direction = targetPosition - currentPos;
        direction.y = 0f;
        float distance = direction.magnitude;

        // 到达目标
        if (distance <= stopDistance)
        {
            ClearTarget();
            return;
        }

        // 移动
        direction.Normalize();
        transform.position += direction * moveSpeed * Time.deltaTime;

        // 朝向移动方向
        if (direction.sqrMagnitude > 0.001f)
        {
            transform.rotation = Quaternion.LookRotation(direction, Vector3.up);
        }

        // 播放走路动画
        if (animator != null)
        {
            animator.SetInteger("speed", 1);
        }
    }

    // 外部入口：把召唤师移动到某点（clamp 后设置目标）。
    public void MoveTo(Vector3 worldPosition)
    {
        Vector3 clamped = ClampToOwnHalf(worldPosition);
        targetPosition = clamped;
        targetPosition.y = transform.position.y; // 保持 Y 不变
        hasTarget = true;

        // 移动中暂停攻击（防风筝规则）
        if (combat != null)
        {
            combat.enabled = false;
        }
    }

    public void ClearTarget()
    {
        hasTarget = false;
        
        // 停止动画
        if (animator != null)
        {
            animator.SetInteger("speed", 0);
        }

        // 站定后恢复自动攻击
        if (combat != null)
        {
            combat.enabled = true;
        }
    }

    // 半场 clamp：X 与 Z 均限制在己方带内。
    private Vector3 ClampToOwnHalf(Vector3 position)
    {
        return new Vector3(
            Mathf.Clamp(position.x, minX, maxX),
            position.y,
            Mathf.Clamp(position.z, minZ, maxZ));
    }

    private bool RaycastGround(out Vector3 point)
    {
        point = Vector3.zero;
        if (mainCamera == null)
        {
            mainCamera = Camera.main;
            if (mainCamera == null) return false;
        }

        Ray ray = mainCamera.ScreenPointToRay(Input.mousePosition);
        if (Physics.Raycast(ray, out RaycastHit hit, 200f, groundMask.value))
        {
            point = hit.point;
            return true;
        }
        return false;
    }

    private bool IsPointerOverUI()
    {
        return EventSystem.current != null && EventSystem.current.IsPointerOverGameObject();
    }
}