using LTGame;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Gameplay.Unit;

namespace Gameplay.Bullet
{
    using Gameplay.Common;
    using UnityEngine;

    public class BulletStateUnitLockFly : BaseBulletState
    {

        private Vector3 _targetPos;
        private GameUnit targetUnit;
        private float _flySpeed;

        public BulletStateUnitLockFly(ViewBullet owner) : base(owner, EBulletState.UnitLockFly)
        {

        }

        protected override void _OnEnter(NBaseState exitState, object param)
        {
            base._OnEnter(exitState, param);
            this.targetUnit = owner.lockUnit;
            this._targetPos = targetUnit.transData.pos;
            _flySpeed = owner.configData.FlySpeed;
        }

        protected override void _OnRunning()
        {
            base._OnRunning();

            var currentPos = owner.rootObj.transform.position;
            if (!targetUnit.statusData.isDead)
            {
                // 更新位置
                _targetPos = targetUnit.transData.pos;
            }
            var targetPos = _targetPos;
            var toTargetPos = targetPos - currentPos;
            var toTargetPosLength = toTargetPos.magnitude;
            var toTargetPosDir = toTargetPos.normalized;
            var moveDistance = _flySpeed * Time.deltaTime;
            if (moveDistance >= toTargetPosLength)
            {
                owner.rootObj.transform.position = targetPos;
                isFinished = true;
                nextState = EBulletState.DamageUnit;
            }
            else
            {
                var newPos = currentPos + toTargetPosDir * moveDistance;
                owner.rootObj.transform.position = newPos;
            }

        }

    }
}