using UnityEngine;
using BaseGames.Combat;

namespace BaseGames.Player.States
{
    /// <summary>
    /// 地面攻击状态（任意段连击）。
    /// 攻速倍率（Stats.AnimatorSpeedMultiplier）缩放 clip 播放速度及 recoveryTime/comboTimeout。
    /// 状态机流程：
    ///   播放动画 → [comboInputOpen] 接受输入 → [cancelWindowOpen] 允许跳跃/冲刺 →
    ///   动画结束 → 硬直(recoveryTime) → 连击等待(comboTimeout) → 无输入则回 Idle
    /// </summary>
    public class AttackState : PlayerStateBase
    {
        private int   _comboIndex;
        private bool  _comboInputPending;  // 连击窗口内已收到攻击输入
        private bool  _comboWindowOpen;    // 当前是否接受连击输入

        // 动画结束后的两阶段计时
        private bool  _waitingAfterAnim;   // 是否在动画结束后等待阶段
        private float _recoveryEndTime;    // 硬直结束时刻
        private float _comboTimeoutEnd;    // 连击等待结束时刻

        public AttackState(PlayerController owner) : base(owner) { }

        public override void OnStateEnter()
        {
            _comboIndex         = 0;
            _comboInputPending  = false;
            _comboWindowOpen    = false;
            _waitingAfterAnim   = false;
            Input.AttackEvent  += OnAttackInput;
            PlayAttackClip();
        }

        public override void OnStateExit()
        {
            Input.AttackEvent -= OnAttackInput;
            Owner.Combat?.DisableAllWeaponHitBoxes();
            Move?.SetCancelWindowOpen(false);
        }

        public override void OnStateUpdate()
        {
            if (!_waitingAfterAnim)
            {
                // ── 动画播放中：只处理取消窗口（跳跃/冲刺打断）──────────────
                if (!Move.CancelWindowOpen) return;
                TryConsumeCancelInput();
                return;
            }

            // ── 动画结束后等待阶段 ─────────────────────────────────────────
            float now = Time.time;

            // 硬直结束后开放取消窗口
            if (!Move.CancelWindowOpen && now >= _recoveryEndTime)
                Move.SetCancelWindowOpen(true);

            // 有缓存的连击输入 → 立即推进
            if (_comboInputPending)
            {
                AdvanceCombo();
                return;
            }

            // 连击超时 → 返回 Idle
            if (now >= _comboTimeoutEnd)
            {
                Owner.TransitionTo(Owner.GetState<IdleState>());
                return;
            }

            // 恢复期结束后仍可跳跃/冲刺取消
            if (Move.CancelWindowOpen)
                TryConsumeCancelInput();
        }

        public override void OnStateFixedUpdate()
        {
            // 攻击动画播放期间无水平输入，仍需每帧调用 Move(0) 叠加 _platformVelocity.x，
            // 使玩家在移动平台上攻击时仍随平台同步移动。
            if (Move.IsGrounded)
                Move.Move(0f);
        }

        // ── 内部 ──────────────────────────────────────────────────────────────

        private void PlayAttackClip()
        {
            _waitingAfterAnim  = false;
            _comboWindowOpen   = false;
            Move.SetCancelWindowOpen(false);

            var weapon = Owner.Weapon?.ActiveWeapon;
            if (weapon == null)
            {
                UnityEngine.Debug.LogWarning("[AttackState] 未找到 ActiveWeapon，请检查 WeaponManager 配置。");
                Owner.TransitionTo(Owner.GetState<IdleState>());
                return;
            }

            var step = weapon.GetGroundStep(_comboIndex);
            if (step.clip == null || step.clip.Clip == null)
            {
                UnityEngine.Debug.LogWarning($"[AttackState] 连击段 {_comboIndex} 动画未配置，请检查 {weapon.weaponId}。");
                Owner.TransitionTo(Owner.GetState<IdleState>());
                return;
            }

            float spd       = Stats?.AnimatorSpeedMultiplier ?? 1f;
            var   animState = Anim.Play(step.clip);
            animState.Speed *= spd;                          // 在 ClipTransition 自身速度基础上叠加攻速

            var events = animState.Events(this);
            events.OnEnd = OnClipEnd;

            // HitBox 时间窗口（capture step by value for closure safety）
            var capturedStep = step;
            events.Add(capturedStep.hitBoxEnter, () =>
                Owner.Combat?.EnableWeaponHitBox(AttackDirection.Ground,
                    capturedStep.hitBoxId, capturedStep.damageSource));
            events.Add(capturedStep.hitBoxExit, () => Owner.Combat?.DisableAllWeaponHitBoxes());
            // 连击输入窗口
            if (capturedStep.comboInputOpen > 0f)
                events.Add(capturedStep.comboInputOpen, () => _comboWindowOpen = true);
            else
                _comboWindowOpen = true;  // 0 = 立即开放

            if (capturedStep.comboInputClose > 0f)
                events.Add(capturedStep.comboInputClose, () => _comboWindowOpen = false);

            // 取消窗口（跳跃/冲刺）
            if (capturedStep.cancelWindowOpen > 0f)
                events.Add(capturedStep.cancelWindowOpen, () => Move.SetCancelWindowOpen(true));
        }

        private void OnClipEnd()
        {
            Owner.Combat?.DisableAllWeaponHitBoxes();
            _comboWindowOpen = false;
            Move.SetCancelWindowOpen(false);

            // 如果已有缓存输入，直接推进（零延迟连击）
            if (_comboInputPending)
            {
                AdvanceCombo();
                return;
            }

            // 进入动画后等待阶段
            var   step  = Owner.Weapon?.ActiveWeapon?.GetGroundStep(_comboIndex) ?? default;
            float spd   = Stats?.AnimatorSpeedMultiplier ?? 1f;
            float now   = Time.time;

            _waitingAfterAnim  = true;
            _recoveryEndTime   = now + step.recoveryTime / spd;
            _comboTimeoutEnd   = _recoveryEndTime + step.comboTimeout / spd;
        }

        private void AdvanceCombo()
        {
            int maxCombo = Owner.Weapon?.ActiveWeapon?.GroundComboCount ?? 1;
            if (_comboIndex < maxCombo - 1)
            {
                _comboIndex++;
                _comboInputPending = false;
                PlayAttackClip();
            }
            else
            {
                // 已是最后一段，忽略多余输入，等待超时
                _comboInputPending = false;
            }
        }

        private void TryConsumeCancelInput()
        {
            if (Buffer.ConsumeJump())
            {
                Owner.TransitionTo(Owner.GetState<JumpState>());
                return;
            }
            var ds = Owner.GetState<DashState>();
            if (ds != null && ds.CanDash
                && Stats != null && Stats.HasAbility(AbilityType.Dash)
                && Buffer.ConsumeDash())
            {
                Owner.TransitionTo(ds);
            }
        }

        private void OnAttackInput()
        {
            if (_comboWindowOpen || _waitingAfterAnim)
                _comboInputPending = true;
        }
    }
}