// Assets/Scripts/World/Liquid/WaterDangerState.cs

using BaseGames.Core.Events;
using BaseGames.Player;
using UnityEngine;

namespace BaseGames.World.Liquid
{
    /// <summary>
    /// 当玩家进入 Water 类型液体且未解锁游泳能力时，触发溺水倒计时。
    /// 订阅 EVT_LiquidEntered / EVT_LiquidExited 事件频道。
    /// </summary>
    public class WaterDangerState : MonoBehaviour
    {
        [SerializeField] private LiquidPhysicsConfigSO _config;
        [SerializeField] private PlayerStats           _playerStats;       // 检查 Swim 能力
        [SerializeField] private LiquidEventChannelSO  _onLiquidEntered;   // EVT_LiquidEntered
        [SerializeField] private LiquidEventChannelSO  _onLiquidExited;    // EVT_LiquidExited
        [SerializeField] private FloatEventChannelSO   _onDrownProgress;   // 0~1 倒计时进度（HUD 用）
        [SerializeField] private VoidEventChannelSO    _onPlayerDrowned;   // 触发死亡

        private float _drownTimer;
        private bool  _isActive;
        private readonly CompositeDisposable _subs = new();

        private void Awake()
        {
            Debug.Assert(_config != null, "[WaterDangerState] _config 未赋值，请在 Inspector 中指定 LiquidPhysicsConfigSO。", this);
        }

        private void OnEnable()
        {
            _onLiquidEntered?.Subscribe(OnEnterLiquid).AddTo(_subs);
            _onLiquidExited?.Subscribe(OnExitLiquid).AddTo(_subs);
        }

        private void OnDisable() => _subs.Clear();

        public void OnEnterLiquid(LiquidEvent evt)
        {
            if (evt.LiquidType != nameof(LiquidType.Water)) return;
            if (_playerStats != null && _playerStats.HasAbility(AbilityType.Swim)) return;
            _isActive   = true;
            _drownTimer = _config.DrownTime;
        }

        public void OnExitLiquid(LiquidEvent evt)
        {
            _isActive   = false;
            _drownTimer = _config.DrownTime;
            _onDrownProgress?.Raise(0f);
        }

        private void Update()
        {
            if (!_isActive) return;
            _drownTimer -= Time.deltaTime;

            float drownTime = _config.DrownTime;
            _onDrownProgress?.Raise(1f - (_drownTimer / drownTime));

            if (_drownTimer <= 0f)
            {
                _isActive = false;
                _onPlayerDrowned?.Raise();
            }
        }
    }
}