using System;
using AibisDream.FixSystem;
using AibisDream.Utility;
using UnityEngine;

namespace AibisDream
{
    public class EngineSystem : MonoBehaviour
    {
        [SerializeField] private float oilDownRatio;
        [SerializeField] private float oilUpRatio;
        [SerializeField] private float acceleratedSpeed;
        [SerializeField] private float resistance;
        [SerializeField] private float airMaxRatio;
        [SerializeField] private float airMinRatio;
        [SerializeField] private float baseAirMax;
        [SerializeField] public int maxLevel;
        [SerializeField] public float invalidTime;

        private bool IsValid => engineData.isValid.Value;

        [Header("系统数据")] [SerializeField] private EngineData engineData;

        public event Action<EngineData> UpdateDashboard;

        private void Awake()
        {
            FixSystemCenter.SystemDic.Register(this);
        }

        private void OnEnable()
        {
            engineData = new EngineData(invalidTime);
        }

        private void Update()
        {
            // 更新部分按时间自然计算的指标
            DataAutoChange();
            // 更新看板
            UpdateDashboard?.Invoke(engineData);
        }

        private void DataAutoChange()
        {
            // 自然减速
            engineData.OilChange(-oilDownRatio);
            engineData.CalcAir(airMaxRatio, airMinRatio, baseAirMax);
            // 推算速度
            engineData.CalcSpeed(acceleratedSpeed, resistance);
        }

        /// <summary>
        /// 加速过程
        /// </summary>
        public void AddOil()
        {
            if (IsValid)
            {
                engineData.OilChange(oilUpRatio);
            }
            // 失效期无法加油门
        }

        public void UpdateAirLevel(int curLevel)
        {
            engineData.UpdateAirLevel(curLevel, maxLevel);
        }
    }

    [Serializable]
    public struct EngineData
    {
        public float curSpeed;
        public float curOil;
        public float curAir;
        public float curAirMin;
        public float curAirMax;
        public int curAirLevel;

        public AutoFlipBool isValid;
        public bool inAirRange;

        public EngineData(float flipDelayTime)
        {
            isValid = new AutoFlipBool(flipDelayTime, true);
            curSpeed = 0;
            curOil = 0;
            curAir = 0;
            curAirMin = 0;
            curAirMax = 0;
            curAirLevel = 0;
            inAirRange = false;
        }

        public void OilChange(float oilChangeRatio)
        {
            curOil = CommonUtil.LimitedAdd(curOil, oilChangeRatio * Time.deltaTime, 1f, 0f);
        }

        public void CalcSpeed(float acceleratedSpeed, float resistance)
        {
            var addNum = inAirRange && isValid.Value
                ? (curOil * acceleratedSpeed - curSpeed * resistance) * Time.deltaTime
                : -curSpeed * resistance * Time.deltaTime;

            curSpeed = CommonUtil.LimitedAdd(curSpeed, addNum, 1f, 0f);
        }

        public void CalcAir(float airMaxRatio, float airMinRatio, float baseAirMax)
        {
            curAirMax = curSpeed * (curAirLevel + 1) * airMaxRatio + baseAirMax;
            curAirMin = curSpeed * (curAirLevel + 1) * airMinRatio;

            curAir = curOil;
            // 如果离开范围且当前在系统有效期，就进入一段失效期
            var curInAirRange = curAir <= curAirMax && curAir >= curAirMin;
            if (inAirRange && !curInAirRange && isValid.Value)
            {
                isValid.Value = false;
            }
        }

        public void UpdateAirLevel(int level, int maxLevel)
        {
            curAirLevel = level;
            if (curAirLevel > maxLevel)
            {
                curAirLevel = maxLevel - 1;
            }

            if (curAirLevel < 0)
            {
                curAirLevel = 0;
            }
        }
    }
}