using UnityEngine;
using MoreMountains.Feedbacks;
using MoreMountains.Tools;
using Unity.Cinemachine;
using System.Collections.Generic;

namespace MoreMountains.FeedbacksForThirdParty
{
    // 定义一个类来保存单个震动实例的状态
    public class MMCinemachinePositionShakeInstance
    {
        public float Duration;
        public float Timer;
        public Vector3 Amplitude;
        public AnimationCurve Curve;
        public float Intensity;
        public TimescaleModes TimescaleMode;
        
        public MMCinemachinePositionShakeInstance(float duration, Vector3 amplitude, AnimationCurve curve, float intensity, TimescaleModes timescaleMode)
        {
            Duration = duration;
            Timer = 0f;
            Amplitude = amplitude;
            Curve = curve;
            Intensity = intensity;
            TimescaleMode = timescaleMode;
        }
    }

    [AddComponentMenu("More Mountains/Feedbacks/Shakers/Cinemachine/MM Cinemachine Position Shaker (Additive)")]
    [RequireComponent(typeof(CinemachineCamera))]
    [RequireComponent(typeof(CinemachineCameraOffset))] // 确保有 Offset 组件
    public class MMCinemachinePositionShaker : MMShaker
    {
        [MMInspectorGroup("Debug Info", true, 43)]
        [MMReadOnly]
        public int ActiveShakesCount = 0; // 仅用于监视当前有多少个震动在叠加

        protected CinemachineCamera _cmCamera;
        protected CinemachineCameraOffset _positionOffset;
        protected Vector3 _initialOffset;
        
        // 维护一个活跃震动的列表
        protected List<MMCinemachinePositionShakeInstance> _activeShakes = new List<MMCinemachinePositionShakeInstance>();

        protected override void Initialization()
        {
            // 注意：我们不调用 base.Initialization()，因为我们不想使用 MMShaker 默认的 Event 监听逻辑，
            // 我们需要完全接管 Shake 的逻辑来实现叠加。
            // 但为了兼容性，如果 Feel 内部有依赖，可以保留，但这里主要逻辑是自定义的。
            _cmCamera = GetComponent<CinemachineCamera>();
            _positionOffset = GetComponent<CinemachineCameraOffset>();
            GrabInitialValues();
        }

        protected override void GrabInitialValues()
        {
            if (_positionOffset != null)
            {
                _initialOffset = _positionOffset.Offset;
            }
        }
        
        // 我们重写 Update 来处理叠加逻辑
        protected override void Update()
        {
            if (_positionOffset == null) return;
            
            // 如果没有活跃的震动，且当前不是初始位置，则复位（可选，作为保险）
            if (_activeShakes.Count == 0)
            {
                Stop();
                return;
            }

            Vector3 totalShakeOffset = Vector3.zero;

            // 倒序遍历以便安全移除
            for (int i = _activeShakes.Count - 1; i >= 0; i--)
            {
                var shake = _activeShakes[i];
                
                // 更新时间
                float deltaTime = (shake.TimescaleMode == TimescaleModes.Scaled) ? Time.deltaTime : Time.unscaledDeltaTime;
                shake.Timer += deltaTime;

                // 计算进度 (0 到 1)
                float percent = Mathf.Clamp01(shake.Timer / shake.Duration);

                // 采样曲线并计算位移
                float curveValue = shake.Curve.Evaluate(percent);
                Vector3 currentOffset = shake.Amplitude * curveValue * shake.Intensity;
                
                // 叠加
                totalShakeOffset += currentOffset;

                // 如果结束，移除
                if (shake.Timer >= shake.Duration)
                {
                    _activeShakes.RemoveAt(i);
                }
            }

            // 应用叠加后的总偏移量 + 初始偏移量
            _positionOffset.Offset = _initialOffset + totalShakeOffset;
            //Debug.Log($"Total Shake Offset Applied: {totalShakeOffset}");
            
            // 更新 Debug 计数
            ActiveShakesCount = _activeShakes.Count;
            
            // 如果所有震动都结束了，强制归位以消除浮点误差
            if (_activeShakes.Count == 0)
            {
                _positionOffset.Offset = _initialOffset;
            }
        }

        /// <summary>
        /// 接收事件
        /// </summary>
        public virtual void OnPositionShakeEvent(MMF_Feedback source, AnimationCurve shakeCurve, float duration, Vector3 positionAmplitude, 
            float feedbacksIntensity = 1.0f, MMChannelData channelData = null, bool resetShakerValuesAfterShake = true, 
            bool resetTargetValuesAfterShake = true, bool forwardDirection = true, TimescaleModes timescaleMode = TimescaleModes.Scaled, bool stop = false)
        {
            if (!CheckEventAllowed(channelData)) return;
            
            if (stop)
            {
                Stop();
                return;
            }

            // 创建新的震动实例并添加到列表
            MMCinemachinePositionShakeInstance newShake = new MMCinemachinePositionShakeInstance(
                duration, 
                positionAmplitude, 
                shakeCurve, 
                feedbacksIntensity, 
                timescaleMode
            );
            
            _activeShakes.Add(newShake);
            Play(source);
        }
        
        // 强制停止所有震动
        public override void Stop()
        {
            _activeShakes.Clear();
            if (_positionOffset != null)
            {
                _positionOffset.Offset = _initialOffset;
            }
        }

        protected override void ResetTargetValues()
        {
            base.ResetTargetValues();
            Stop();
        }

        public override void StartListening()
        {
            // 注意：这里我们依然使用基类的注册机制，或者直接在这里注册
            base.StartListening();
            MMCinemachinePositionShakeEvent.Register(OnPositionShakeEvent);
        }

        public override void StopListening()
        {
            base.StopListening();
            MMCinemachinePositionShakeEvent.Unregister(OnPositionShakeEvent);
        }
    }
}