using System;
using System.Collections.Generic;
using Cielonos.MainGame.Buffs.Character;
using Cielonos.MainGame.Characters;
using SLSUtilities.General;
using UnityEngine;

namespace Cielonos.MainGame.Inventory.Collections
{
    /// <summary>
    /// 衰变加速线圈 / Decay Acceleration Coil (Passive, Graham)
    /// 玩家光环范围（15m）内的敌人，其 Decay 伤害间隔缩短 50%。离开光环后恢复。
    /// </summary>
    public class DecayAccelerationCoil : PassiveEquipmentBase
    {
        private const string EventKey = nameof(DecayAccelerationCoil);

        /// <summary>
        /// 记录已被修改 Decay 间隔的敌人及其原始间隔值，用于离开光环时恢复。
        /// </summary>
        private readonly Dictionary<CharacterBase, float> _modifiedEnemies = new();

        public override void OnObtained()
        {
            base.OnObtained();

            auraSm = new AuraSubmodule(this, passiveAttributeSm.GetItemAttribute("AuraRadius"));

            Action<CharacterBase> onEnter = OnEnemyEnterAura;
            Action<CharacterBase> onExit = OnEnemyExitAura;
            Action<CharacterBase> onStay = OnEnemyStayAura;

            auraSm.onOtherEnterAura.Add(EventKey, onEnter.ToPrioritized());
            auraSm.onOtherExitAura.Add(EventKey, onExit.ToPrioritized());
            auraSm.onOtherStayAura.Add(EventKey, onStay.ToPrioritized());
        }

        public override void OnDiscarded()
        {
            // 恢复所有被修改的 Decay 间隔
            auraSm?.Dispose();
            _modifiedEnemies.Clear();

            base.OnDiscarded();
        }

        protected override void Update()
        {
            base.Update();
            auraSm?.Update(player.selfTimeSm.DeltaTime);
        }

        /// <summary>
        /// 敌人进入光环时，尝试加速其 Decay 间隔。
        /// </summary>
        private void OnEnemyEnterAura(CharacterBase enemy)
        {
            TryAccelerateDecay(enemy);
        }

        /// <summary>
        /// 敌人持续处于光环内时，检查是否有新施加的 Decay 需要加速。
        /// </summary>
        private void OnEnemyStayAura(CharacterBase enemy)
        {
            if (_modifiedEnemies.ContainsKey(enemy)) return;
            TryAccelerateDecay(enemy);
        }

        /// <summary>
        /// 敌人离开光环时，恢复其 Decay 间隔。
        /// </summary>
        private void OnEnemyExitAura(CharacterBase enemy)
        {
            RestoreDecayInterval(enemy);
        }

        /// <summary>
        /// 尝试加速目标身上的 Decay 伤害间隔。
        /// </summary>
        private void TryAccelerateDecay(CharacterBase enemy)
        {
            if (!enemy.buffSm.TryGetBuff(out Decay decay)) return;
            if (_modifiedEnemies.ContainsKey(enemy)) return;

            _modifiedEnemies[enemy] = decay.Interval;
            float acceleratedInterval = decay.Interval * passiveAttributeSm.GetItemAttribute("IntervalMultiplier");
            decay.timeSubmodule.intervalActions[0].SetInterval(acceleratedInterval);
        }

        /// <summary>
        /// 恢复目标身上的 Decay 伤害间隔至原始值。
        /// </summary>
        private void RestoreDecayInterval(CharacterBase enemy)
        {
            if (!_modifiedEnemies.Remove(enemy, out float originalInterval)) return;
            if (!enemy.buffSm.TryGetBuff(out Decay decay)) return;
            decay.timeSubmodule.intervalActions[0].SetInterval(originalInterval);
        }
    }
}