using Convention;
using Demo.Attr;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;

namespace Demo.Game
{
    [Scriptable]
    public class LookAtAnchor : Updatement<int>
    {
        public static LookAtAnchor Make()
        {
            return new GameObject().AddComponent<LookAtAnchor>();
        }

        protected override int Lerp(int begin, int end, float t)
        {
            return begin;
        }

        private readonly List<ScriptableObject> LookAtCache = new();

        [Content] public int LookAtObject;
        [Content] public bool IsEnableUpdateEveryTick = false;

        protected override void UpdateData(int data)
        {
            ScriptableObject target = LookAtCache[LookAtObject];
            if (data != LookAtObject)
            {
                LookAtObject = data;
                if (target != null)
                    transform.LookAt(target.transform);
            }
            else if (IsEnableUpdateEveryTick)
            {
                if (target != null)
                    transform.LookAt(target.transform);
            }
        }

        /// <summary>
        /// 在指定时刻切换面向的物体，并尝试一次更新
        /// </summary>
        [Convention.RScript.Variable.Attr.Method]
        public void Add(float time, ScriptableObject target)
        {
            LookAtCache.Add(target);
            ManualAddEntry(time, LookAtCache.Count - 1, default);
        }

        /// <summary>
        /// 启动自动更新，将持续锁定面向的物体并更新
        /// </summary>
        [Convention.RScript.Variable.Attr.Method]
        public void EnableUpdateEveryTick()
        {
            IsEnableUpdateEveryTick = true;
        }
    }
}