using UnityEngine;

namespace BaseGames.Player.States
{
    /// <summary>
    /// 空中冲刺状态（架构 05_PlayerModule §12）。
    /// 与地面 DashState 独立，消耗 MaxAerialDashes 次数；
    /// 空中冲刺可向任意方向（使用移动输入方向，无输入则使用朝向）。
    /// </summary>
    public class AerialDashState : PlayerStateBase
    {
        private float _timer;
        private int   _aerialDashesLeft;
        private int   _facingDir;

        public bool HasAerialDash => _aerialDashesLeft > 0;

        public AerialDashState(PlayerController owner) : base(owner)
        {
            _aerialDashesLeft = 1;
        }

        public override void OnStateEnter()
        {
            _aerialDashesLeft = Mathf.Max(0, _aerialDashesLeft - 1);
            _facingDir        = Owner.FacingDirection;
            _timer            = Cfg.DashDuration;

            // 无敌帧
            Stats?.BeginInvincibility(Cfg.DashDuration + 0.05f);

            // 关闭重力，施加冲刺速度（空中冲刺不改变垂直速度）
            Move?.SetGravityScale(0f);
            float dir = Input.MoveInput.x != 0 ? Mathf.Sign(Input.MoveInput.x) : _facingDir;
            Move?.Dash(new Vector2(dir, 0f), Cfg.DashSpeed);

            // 播放冲刺动画（复用地面冲刺动画）
            if (AnimCfg?.Dash != null) Anim?.Play(AnimCfg.Dash);
        }

        public override void OnStateUpdate()
        {
            _timer -= Time.deltaTime;
            if (_timer <= 0f)
            {
                Move?.SetGravityScale(Cfg.DefaultGravityScale);
                Owner.TransitionTo(Owner.GetState<FallState>());
            }
        }

        public override void OnStateExit()
        {
            Move?.SetGravityScale(Cfg.DefaultGravityScale);
        }

        public override void OnStateFixedUpdate()
        {
            // 冲刺期间锁定速度
            if (_timer > 0f)
            {
                float dir = Input.MoveInput.x != 0 ? Mathf.Sign(Input.MoveInput.x) : _facingDir;
                Move?.Dash(new Vector2(dir, 0f), Cfg.DashSpeed);
            }
        }

        /// <summary>着地时重置空中冲刺次数（由 PlayerController 在着地时调用）。</summary>
        public void ResetAerialDashes()
        {
            _aerialDashesLeft = Cfg.MaxAerialDashes;
        }
    }
}