using System;
using UnityEngine;

namespace Skill_V2
{
    [Serializable]
    public struct Skill_V2Property
    {
        public uint id;
        public float defaultSkillCoolTime;
    }

    public class Skill : Entity
    {
        [SerializeField] Skill_V2Property property;

        [SerializeField] StateHandler stateHandler;
        [SerializeField] SkillState[] sequences;

        Entity caster;
        int currentSequenceIndex = -1;
        float elapsedCoolTime;

        public Skill_V2Property Property => property;
        public SkillState CurrentSequence => currentSequenceIndex >= 0 ? sequences[currentSequenceIndex] : null;
        public bool IsInCoolTime => elapsedCoolTime < property.defaultSkillCoolTime;
        public float CoolTimeRemainTime => Mathf.Clamp(property.defaultSkillCoolTime - elapsedCoolTime, 0, property.defaultSkillCoolTime);
        public float ElapsedCoolTime => Mathf.Clamp(elapsedCoolTime, 0, property.defaultSkillCoolTime);
        public float ElapsedCoolTimeRate { get; private set; }

        private void Awake()
        {
            for (int i = 0; i < sequences.Length; ++i)
            {
                sequences[i].SetOwner(this);
            }
        }

        private void Update()
        {
            if (CurrentSequence != null && CurrentSequence.IsDone)
            {
                currentSequenceIndex++;
                if (currentSequenceIndex < sequences.Length)
                {
                    stateHandler.ChangeState(sequences[currentSequenceIndex]);
                }
                else
                {
                    currentSequenceIndex = -1;
                    stateHandler.ChangeState(null);
                    caster = null;
                    gameObject.SetActive(false);
                }
            }
        }

        public void UpdateSkillCoolTime()
        {
            if (!IsInCoolTime) return;
            elapsedCoolTime += Time.fixedUnscaledDeltaTime;
            ElapsedCoolTimeRate = Mathf.Clamp01(elapsedCoolTime / property.defaultSkillCoolTime);
        }

        public void Cast(Entity caster)
        {
            this.caster = caster;
            currentSequenceIndex = 0;

            transform.position = caster.CenterPivot;
            ChangeLookDirection(caster.LookDirection);
            gameObject.SetActive(true);
            stateHandler.ChangeState(CurrentSequence);
        }

        public void StartCoolTime()
        {
            elapsedCoolTime = 0f;
        }

        public void Stop()
        {
            CurrentSequence?.Stop();
            currentSequenceIndex = -1;
            stateHandler?.ChangeState(null);
            caster = null;
            gameObject.SetActive(false);
        }
    }
}