#if GRAPH_DESIGNER
using UnityEngine;
using Opsive.BehaviorDesigner.Runtime.Tasks;
using Opsive.BehaviorDesigner.Runtime.Tasks.Actions;
using BaseGames.Enemies;

namespace BaseGames.Enemies.AI
{
    /// <summary>
    /// BD Action：按预设路点顺序巡逻（支持 Transform 引用或内联 Vector2 坐标两种模式）。
    ///
    /// <list type="bullet">
    ///   <item><b>m_Waypoints（Transform[]）</b>：拖入场景中的路点对象；适合动态路点（可在运行时移动）。</item>
    ///   <item><b>m_InlineWaypoints（Vector2[]）</b>：直接填写世界坐标；无需在场景中放置对象，编辑器中以 Gizmo 可视化路径。</item>
    ///   <item>两者同时设置时 m_Waypoints 优先。</item>
    /// </list>
    ///
    /// 到达最后一个路点后可循环（Loop）或往返（PingPong）。
    /// 与 PathBerserker2d 集成：通过 IPathAgent.RequestMoveTo 导航，支持跨平台跳跃 NavLink。
    /// </summary>
    [TaskName("Patrol (Waypoints)")]
    [TaskCategory("BaseGames/Enemy/Movement")]
    [TaskDescription("按预设路点顺序巡逻；支持 Transform 引用或内联 Vector2 坐标，可循环或折返")]
    public sealed class BD_PatrolWaypoints : Action
    {
        [Tooltip("路点列表（世界空间 Transform）；与 m_InlineWaypoints 同时设置时此项优先")]
        [SerializeField] private Transform[] m_Waypoints;

        [Tooltip("内联路点坐标（世界空间 Vector2）；m_Waypoints 为空时使用；在 Scene 视图中以绿色 Gizmo 可视化")]
        [SerializeField] private Vector2[] m_InlineWaypoints;

        [Tooltip("到达路点的判定半径（m）")]
        [SerializeField] private float m_ArriveRadius = 0.3f;

        [Tooltip("true = 往返; false = 循环")]
        [SerializeField] private bool m_PingPong = false;

        [Tooltip("每个路点到达后等待时长（s）")]
        [SerializeField] private float m_WaitAtWaypoint = 0f;

        // 首次启动重试间隔：OnStart() 的第一次 RequestCurrent() 可能因 NavAgent 尚未完成
        // UpdateMappedPosition()（脚本执行顺序问题）而静默失败。此值只需大于一帧即可。
        private const float InitialRetryDelay = 0.05f;

        // 正常巡逻中卡住的重试间隔：必须足够长，使任何在途 PB2d 路径请求
        // （Pending → Finished → HandlePathRequest 消费）都已处理完毕，避免竞争覆盖。
        private const float StuckRetryDelay = 0.5f;

        private EnemyBase _enemy;
        private int       _index      = 0;
        private int       _dir        = 1;
        private float     _waitTimer  = 0f;
        private bool      _waiting    = false;
        private float     _stuckTimer = 0f;
        private bool      _pathFailed = false;
        private bool      _hasMoved   = false; // 首次成功开始移动后置 true

        // ── 统一路点访问 ────────────────────────────────────────────────────
        private int WaypointCount =>
            m_Waypoints != null && m_Waypoints.Length > 0
                ? m_Waypoints.Length
                : m_InlineWaypoints?.Length ?? 0;

        private Vector2 GetWaypoint(int index)
        {
            if (m_Waypoints != null && m_Waypoints.Length > 0)
            {
                var t = m_Waypoints[index];
                return t != null ? (Vector2)t.position : (Vector2)transform.position;
            }
            return m_InlineWaypoints != null && index < m_InlineWaypoints.Length
                ? m_InlineWaypoints[index]
                : (Vector2)transform.position;
        }

        // ── BD 生命周期 ─────────────────────────────────────────────────────
        public override void OnAwake() => _enemy = gameObject.GetComponent<EnemyBase>();

        public override void OnStart()
        {
            if (WaypointCount == 0) return;
            _waiting    = false;
            _waitTimer  = 0f;
            _stuckTimer = 0f;
            _pathFailed = false;
            _hasMoved   = false;
            _enemy?.SetAiPhase(AiPhase.Patrol);

            if (_enemy?.Nav != null)
            {
                _enemy.Nav.OnGoalReached  += HandleGoalReached;
                _enemy.Nav.OnNavPathFailed += HandlePathFailed;
            }

            RequestCurrent();
        }

        public override TaskStatus OnUpdate()
        {
            if (_enemy == null || WaypointCount == 0)
                return TaskStatus.Failure;

            if (_waiting)
            {
                _waitTimer -= Time.deltaTime;
                if (_waitTimer > 0f) return TaskStatus.Running;
                _waiting = false;
                Advance();
                RequestCurrent();
                return TaskStatus.Running;
            }

            // 兜底重试：用时间门控避免与 PB2d 的 Finished-状态路径请求产生竞争。
            // 首次启动前（_hasMoved=false）使用短延迟，处理 NavAgent 位置映射尚未就绪的情况；
            // 正常巡逻中使用长延迟，确保在途路径请求已被 HandlePathRequest 消费完毕。
            if (_enemy.Nav != null)
            {
                if (!_enemy.Nav.IsMoving)
                {
                    _stuckTimer += Time.deltaTime;
                    float retryDelay = _hasMoved ? StuckRetryDelay : InitialRetryDelay;
                    if (_stuckTimer >= retryDelay)
                    {
                        _stuckTimer = 0f;
                        _pathFailed = false;
                        RequestCurrent();
                    }
                }
                else
                {
                    _hasMoved   = true;
                    _stuckTimer = 0f;
                }
            }

            return TaskStatus.Running;
        }

        public override void OnEnd()
        {
            if (_enemy?.Nav != null)
            {
                _enemy.Nav.OnGoalReached   -= HandleGoalReached;
                _enemy.Nav.OnNavPathFailed -= HandlePathFailed;
            }
            _enemy?.StopMovement();
        }

        // ── 内部辅助 ────────────────────────────────────────────────────────
        private void HandleGoalReached()
        {
            _hasMoved   = true;
            _stuckTimer = 0f;
            _pathFailed = false;
            if (m_WaitAtWaypoint > 0f)
            {
                _waiting   = true;
                _waitTimer = m_WaitAtWaypoint;
                _enemy?.StopMovement();
            }
            else
            {
                Advance();
                RequestCurrent();
            }
        }

        // 路径失败时不在回调中立即重试——此时 NavAgent.HandlePathRequest 尚未调用
        // currentPathRequest.Reset()，直接提交新请求会被随后的 Reset() 覆盖清除。
        // 改为设置标志，交由 OnUpdate 的计时兜底在下一帧安全重试。
        private void HandlePathFailed()
        {
            _pathFailed = true;
            _stuckTimer = 0f; // 重置计时器，使兜底在 StuckRetryDelay 后触发
        }

        private void RequestCurrent()
        {
            if (WaypointCount == 0) return;
            _enemy.MoveTo(GetWaypoint(_index));
        }

        private void Advance()
        {
            if (WaypointCount <= 1) return;
            if (m_PingPong)
            {
                _index += _dir;
                if (_index >= WaypointCount) { _index = WaypointCount - 2; _dir = -1; }
                else if (_index < 0)         { _index = 1;                 _dir =  1; }
            }
            else
            {
                _index = (_index + 1) % WaypointCount;
            }
        }

        // ── Gizmo 可视化（仅 m_InlineWaypoints 模式）────────────────────────
#if UNITY_EDITOR
        private new void OnDrawGizmos()
        {
            if (m_InlineWaypoints == null || m_InlineWaypoints.Length < 1) return;
            // m_Waypoints 存在时不绘制，避免与场景路点重叠
            if (m_Waypoints != null && m_Waypoints.Length > 0) return;

            Gizmos.color = new Color(0.2f, 0.85f, 0.2f, 0.8f);
            for (int i = 0; i < m_InlineWaypoints.Length; i++)
            {
                Gizmos.DrawWireSphere(m_InlineWaypoints[i], m_ArriveRadius);

                if (i < m_InlineWaypoints.Length - 1)
                    Gizmos.DrawLine(m_InlineWaypoints[i], m_InlineWaypoints[i + 1]);
            }

            // PingPong 时也画返回线；Loop 时画首尾连接线
            if (m_InlineWaypoints.Length >= 2)
            {
                if (m_PingPong)
                {
                    // 往返：虚线效果（半透明线）
                    Gizmos.color = new Color(0.2f, 0.85f, 0.2f, 0.35f);
                    Gizmos.DrawLine(m_InlineWaypoints[m_InlineWaypoints.Length - 1], m_InlineWaypoints[0]);
                }
                else
                {
                    // 循环：画首尾连接
                    Gizmos.color = new Color(0.2f, 0.85f, 0.2f, 0.5f);
                    Gizmos.DrawLine(m_InlineWaypoints[m_InlineWaypoints.Length - 1], m_InlineWaypoints[0]);
                }
            }

            // 编辑器标签（路点序号）
            UnityEditor.Handles.color = new Color(0.2f, 0.85f, 0.2f, 1f);
            for (int i = 0; i < m_InlineWaypoints.Length; i++)
                UnityEditor.Handles.Label(m_InlineWaypoints[i] + Vector2.up * 0.25f, $"WP{i}");
        }
#endif
    }
}
#endif