using Cielonos.MainGame.Buffs.Character;
using Opsive.BehaviorDesigner.Runtime;
using SLSUtilities.General;
using UnityEngine;
using UnityEngine.AI;

namespace Cielonos.MainGame.Characters
{
    public partial class AutomataLandMovementSubcontroller : LandMovementSubcontroller
    {
        public NavMeshAgent navMeshAgent => (owner as Automata)!.behaviorSc.navMeshAgent;
        public LerpFloat animatorMoveSpeedX;
        public LerpFloat animatorMoveSpeedZ;

        public override void Initialize()
        {
            base.Initialize();
            navMeshAgent.isStopped = true;
            animatorMoveSpeedX = new LerpFloat(0f, 5f);
            animatorMoveSpeedZ = new LerpFloat(0f, 5f);
        }

        private Vector3 lastDirection;
        
        protected override void Update()
        {
            base.Update();
            HandleNavMeshState();
        }

        protected override void OnAnimatorMove()
        {
            if (owner.selfTimeSm.DeltaTime == 0 || owner.statusSm.isDead)
            {
                return;
            }
            
            if (navMeshAgent != null && navMeshAgent.enabled)
            {
                UpdateNavigationAnimParams();
            }
           
            base.OnAnimatorMove();
            InitiativeMove();
            lastDirection = transform.forward;
        }

        protected override void InitiativeMove()
        {
            if (navMeshAgent.enabled)
            {
                navMeshAgent.Move(finalMovementVelocity);
                navMeshAgent.baseOffset += finalMovementVelocity.y;
                navMeshAgent.baseOffset = Mathf.Max(navMeshAgent.baseOffset, 0f);
            }
            else
            {
                if (owner.collisionSc.useCharacterController)
                {
                    owner.collisionSc.characterController.Move(finalMovementVelocity);
                }
                else
                {
                    Vector3 startPosition = owner.collisionSc.mainRigidbody.position;
                    owner.collisionSc.mainRigidbody.MovePosition(startPosition + finalMovementVelocity);
                }
            }
        }

        // ────────────────────────────────────────────────────────────────────
        //  Navigation Animation
        // ────────────────────────────────────────────────────────────────────

        private void UpdateNavigationAnimParams()
        {
            if (!is8WayMovement)
            {
                animatorMoveSpeedZ.targetValue = navMeshAgent.isStopped
                    ? 0f
                    : navMeshAgent.velocity.magnitude
                      + Vector3.Angle(lastDirection, transform.forward) / owner.selfTimeSm.DeltaTime * 0.02f;

                animatorMoveSpeedZ.Update(0.2f, 1);
                animator.SetFloat("MoveSpeedZ", animatorMoveSpeedZ.currentValue);
            }
            else
            {
                if (!navMeshAgent.isStopped)
                {
                    Vector3 velocity = navMeshAgent.velocity;
                    animatorMoveSpeedX.targetValue = Vector3.Dot(velocity, transform.right);
                    animatorMoveSpeedZ.targetValue = Vector3.Dot(velocity, transform.forward);
                }
                else
                {
                    animatorMoveSpeedX.targetValue = 0f;
                    animatorMoveSpeedZ.targetValue = 0f;
                }

                animatorMoveSpeedX.Update(0.2f, 1);
                animatorMoveSpeedZ.Update(0.2f, 1);
                animator.SetFloat("MoveSpeedX", animatorMoveSpeedX.currentValue);
                animator.SetFloat("MoveSpeedZ", animatorMoveSpeedZ.currentValue);
            }
        }
    }

    // ════════════════════════════════════════════════════════════════════════
    //  Hit Impact & Stun
    // ════════════════════════════════════════════════════════════════════════

    public partial class AutomataLandMovementSubcontroller
    {
        private const float DEFAULT_STUN_DURATION = 0.25f;

        public bool stagnantFirstHalf;
        public bool stagnantLastHalf;

        /// <summary>当前是否处于击飞引发的眩晕状态（由落地检测解除）。</summary>
        private bool isLaunchStunned;

        private Automata Automata => owner as Automata;

        /// <summary>
        /// 处理受击位移（击退 / 击飞）。
        /// </summary>
        /// <param name="force">力的矢量（XZ = 击退方向和强度，Y = 击飞强度）。</param>
        /// <param name="isLaunch">是否为"击飞"（无视抗性，自动眩晕）。</param>
        /// <param name="isParabolic">Y 轴是否使用抛物线物理。仅 isLaunch 时有意义。</param>
        /// <param name="duration">脉冲持续时间（秒），0 使用默认值。</param>
        /// <param name="curve">速度衰减曲线，null 使用默认 EaseOut。</param>
        /// <param name="applyStun">（仅击退）是否附加眩晕状态。击飞始终附加眩晕。</param>
        /// <param name="stunDuration">（仅击退）眩晕持续时间（秒），0 跟随脉冲持续时间。</param>
        /// <param name="gravityMultiplier">重力缩放倍率。0 = 浮空，1 = 正常（默认），大于 1 = 加速坠落。</param>
        /// <param name="gravityDuration">重力修正持续时间（秒）。0 = 不施加重力修正。</param>
        public void ApplyHitImpact(Vector3 force, bool isLaunch, bool isParabolic,
            float duration = 0f, AnimationCurve curve = null,
            bool applyStun = false, float stunDuration = 0f,
            float gravityMultiplier = 1f, float gravityDuration = 0f)
        {
            if (isLaunch && navMeshAgent.enabled) navMeshAgent.enabled = false;

            if (!stagnantFirstHalf && !stagnantLastHalf)
            {
                stagnantFirstHalf = true;
            }

            impulseSm.ApplyImpulse(force, isLaunch, duration, curve, isParabolic);

            if (isLaunch)
            {
                ApplyStun();
                isLaunchStunned = true;
            }
            else if (applyStun)
            {
                float effectiveDuration = stunDuration > 0f
                    ? stunDuration
                    : (duration > 0f ? duration : DEFAULT_STUN_DURATION);
                ApplyStun(effectiveDuration);
            }

            ApplyGravityModifier(gravityMultiplier, gravityDuration);
        }

        // ────────────────────────────────────────────────────────────────────
        //  NavMesh State Machine
        // ────────────────────────────────────────────────────────────────────

        private void HandleNavMeshState()
        {
            if (navMeshAgent == null) return;

            if (stagnantFirstHalf && !isOnGround && finalMovementVelocity.y < 0)
            {
                stagnantFirstHalf = false;
                stagnantLastHalf = true;
            }

            if (stagnantLastHalf && isOnGround)
            {
                impulseSm.ClearLaunch();
                TryRemoveLaunchStun();

                if (!navMeshAgent.enabled)
                {
                    navMeshAgent.enabled = true;
                    navMeshAgent.Warp(transform.position);
                }

                stagnantFirstHalf = false;
                stagnantLastHalf = false;
            }
        }

        // ────────────────────────────────────────────────────────────────────
        //  Gravity Modifier
        // ────────────────────────────────────────────────────────────────────

        /// <summary>
        /// 通过 VerticalMoveModification Buff 施加重力修正。
        /// multiplier 大于 1 时先清除已有浮空 Buff，确保 Finisher 坠落生效。
        /// </summary>
        private void ApplyGravityModifier(float multiplier, float duration)
        {
            if (duration <= 0f) return;

            if (multiplier > 1f)
            {
                if (owner.buffSm.TryGetBuff<VerticalMoveModification>(out var existingBuff))
                {
                    existingBuff.Remove();
                }
            }

            new VerticalMoveModification(duration, multiplier).Apply(owner);
        }

        // ────────────────────────────────────────────────────────────────────
        //  Stun Helpers
        // ────────────────────────────────────────────────────────────────────

        /// <summary>
        /// 施加眩晕。无参数版为永久眩晕（击飞用），由落地检测解除；
        /// 带 duration 版为定时眩晕（击退用），到期自动解除。
        /// </summary>
        private void ApplyStun(float duration = -1f)
        {
            Automata.statusSm.AddStatus(StatusType.Stun);
            Automata.behaviorSc.mainBehaviorTree.StopBehavior(true);

            if (duration > 0f)
            {
                owner.selfTimeSm.AddLocalTimer(duration, () => TryResumeFromStun());
            }
        }

        /// <summary>
        /// 尝试解除击飞眩晕（落地时调用）。
        /// </summary>
        private void TryRemoveLaunchStun()
        {
            if (!isLaunchStunned) return;
            isLaunchStunned = false;
            TryResumeFromStun();
        }

        /// <summary>
        /// 移除一层 Stun，若所有 Stun 层归零则恢复行为树。
        /// </summary>
        private void TryResumeFromStun()
        {
            Automata.statusSm.RemoveStatus(StatusType.Stun);

            if (!Automata.statusSm.HasStatus(StatusType.Stun))
            {
                Automata.behaviorSc.mainBehaviorTree.StartBehavior();
            }
        }
    }
}