using System.Collections.Generic;
using UnityEngine.Rendering.PostProcessing;
using UnityEngine;

//用于表现的全局效果 timescale 后处理参数等
namespace Game
{
    public delegate void GlobalEffectHandler(float scale);
    public enum EGlobalEffectType
    {
        Timescale,
        Aberration,
        Fov,
        Max,
    }
    public class GlobalEffectInfo
    {
        public float MFrom;
        public float MTo;
        public float MTimeDuration;
        public float MTimeLeft;
        public float MTimeDelay;
    }
    public class GlobalEffectManager : ManagerBase<GlobalEffectManager>
    {
        private Dictionary<EGlobalEffectType, Queue<GlobalEffectInfo>> _mGlobalEffectDict = new Dictionary<EGlobalEffectType, Queue<GlobalEffectInfo>>();
        private Dictionary<EGlobalEffectType, GlobalEffectHandler> _mGlobalEffectHandlerDict;
        public GlobalEffectManager() { }
        public override void OnCreate()
        {
            for (int i = 0; i < (int)EGlobalEffectType.Max; i++)
            {
                _mGlobalEffectDict[(EGlobalEffectType)i] = new Queue<GlobalEffectInfo>();
            }
            _mGlobalEffectHandlerDict = new Dictionary<EGlobalEffectType, GlobalEffectHandler>(){
                {EGlobalEffectType.Timescale,SetTimeScale},
                {EGlobalEffectType.Aberration,SetAberration},
                {EGlobalEffectType.Fov,SetFov},
            };
        }
        public override void Update()
        {
            foreach (var item in _mGlobalEffectDict)
            {
                var type = item.Key;
                var infoQueue = item.Value;
                if (infoQueue.Count == 0)
                {
                    continue;
                }
                var info = infoQueue.Peek();
                if (info.MTimeLeft <= 0)
                {
                    continue;
                }
                if (info.MTimeDelay > 0)
                {
                    info.MTimeDelay -= Time.unscaledDeltaTime;
                    continue;
                }
                info.MTimeDelay = 0;
                var pastRate = (info.MTimeDuration - info.MTimeLeft) / info.MTimeDuration;
                var scaleRate = pastRate * pastRate;//y=x^2曲线
                var scaleDir = info.MTo - info.MFrom;
                var targetScale = info.MFrom + scaleDir * scaleRate;
                info.MTimeLeft -= Time.unscaledDeltaTime;
                if (info.MTimeLeft <= 0)
                {
                    info.MTimeLeft = 0;
                    targetScale = info.MTo;
                    infoQueue.Dequeue();
                }
                SetScale(type, targetScale);
            }
        }
        public override void OnDestroy() { }
        public void SetEffect(EGlobalEffectType type, float scale)
        {
            SetEffectLerp(type, scale, scale, 0);
        }
        public void SetEffectLerp(EGlobalEffectType type, float scaleFrom, float scaleTo, float duration, float delay = 0)
        {
            //清空队列 并且设置当前值
            SetScale(type, scaleFrom);
            var infoQueue = _mGlobalEffectDict[type];
            infoQueue.Clear();
            var info = new GlobalEffectInfo();
            info.MFrom = scaleFrom;
            info.MTo = scaleTo;
            info.MTimeDuration = duration;
            info.MTimeLeft = duration;
            info.MTimeDelay = delay;
            infoQueue.Enqueue(info);
        }
        public void AppendEffectLerp(EGlobalEffectType type, float scaleFrom, float scaleTo, float duration, float delay = 0)
        {
            //加入队列
            var infoQueue = _mGlobalEffectDict[type];
            var info = new GlobalEffectInfo();
            info.MFrom = scaleFrom;
            info.MTo = scaleTo;
            info.MTimeDuration = duration;
            info.MTimeLeft = duration;
            info.MTimeDelay = delay;
            infoQueue.Enqueue(info);
        }

        private void SetScale(EGlobalEffectType type, float scale)
        {
            _mGlobalEffectHandlerDict[type](scale);
        }
        private void SetTimeScale(float scale)
        {
            Time.timeScale = scale;
        }
        private void SetAberration(float scale)
        {
            var setting = Util.GetPostProcessSetting<ChromaticAberration>();
            setting.intensity.value = scale;
        }
        private void SetFov(float scale)
        {
            var virtualCamera = Util.GetVirtualCamera();
            var normalFOV = 25;//TODO 跟随相机设置
            virtualCamera.m_Lens.FieldOfView = scale * normalFOV;
        }

    }
    public abstract partial class Util
    {
        public static void SetTimeScale(float scale)
        {
            GlobalEffectManager.Instance.SetEffect(EGlobalEffectType.Timescale, scale);
        }
        public static void SetGlobalEffect(EGlobalEffectType type, float scaleFrom, float scaleTo, float duration)
        {
            GlobalEffectManager.Instance.SetEffectLerp(type, scaleFrom, scaleTo, duration);
        }
        public static void AppendGlobalEffect(EGlobalEffectType type, float scaleFrom, float scaleTo, float duration)
        {
            GlobalEffectManager.Instance.AppendEffectLerp(type, scaleFrom, scaleTo, duration);
        }

        public static void SetTimeScaleEffect(float scaleFrom, float scaleTo, float duration)
        {
            SetGlobalEffect(EGlobalEffectType.Timescale, scaleFrom, scaleTo, duration);
        }
        public static void SetAberrationEffect(float scaleFrom, float scaleTo, float duration)
        {
            SetGlobalEffect(EGlobalEffectType.Aberration, scaleFrom, scaleTo, duration);
        }
        public static void SetFovEffect(float scaleFrom, float scaleTo, float duration)
        {
            SetGlobalEffect(EGlobalEffectType.Fov, scaleFrom, scaleTo, duration);
        }
        public static void AppendTimeScaleEffect(float scaleFrom, float scaleTo, float duration)
        {
            AppendGlobalEffect(EGlobalEffectType.Timescale, scaleFrom, scaleTo, duration);
        }
        public static void AppendAberrationEffect(float scaleFrom, float scaleTo, float duration)
        {
            AppendGlobalEffect(EGlobalEffectType.Aberration, scaleFrom, scaleTo, duration);
        }
        public static void AppendFovEffect(float scaleFrom, float scaleTo, float duration)
        {
            AppendGlobalEffect(EGlobalEffectType.Fov, scaleFrom, scaleTo, duration);
        }
    }
}