using UnityEngine;

namespace AibisDream.FixSystem
{
    public class CableReel : MonoBehaviour
    {
        [Header("转盘设置")]
        [SerializeField] private float torqueStrength = 200f; // 扭矩强度
        [SerializeField] private float angularDamping = 5f;   // 角速度阻尼
        [SerializeField] private float maxHalfAngle = 60f;    // 单侧最大转角（总范围约 2× 此值 ≈ 120°）
        [SerializeField] private float returnSpeed = 4f;      // 闲置回正速度
        
        private CablePanel cablePanel;
        private float angularVelocity;    // 角速度
        private float currentAngle;       // 当前角度
        public Vector3 outletPos { get; private set; }        // 出线口位置
        private SpriteRenderer spriteRenderer;
        private float reelRadius;         // 转盘半径
        
        private void Start()
        {
            // 获取CablePanel引用
            cablePanel = transform.GetComponentInParent<CablePanel>();
            currentAngle = transform.eulerAngles.z;
            
            // 获取SpriteRenderer并计算半径
            spriteRenderer = GetComponent<SpriteRenderer>();
            if (spriteRenderer != null)
            {
                // 使用sprite的bounds来计算半径
                reelRadius = spriteRenderer.bounds.extents.y; // 使用y方向的半高作为半径
            }
            else
            {
                Debug.LogWarning("CableReel没有SpriteRenderer组件！");
                reelRadius = 0.5f; // 默认值
            }

            // 初始化出线口位置
            UpdateOutletPosition();
        }

        private void UpdateOutletPosition()
        {
            // 更新出线口位置（圆形本地坐标 (0, -radius) 转成世界坐标）
            outletPos = transform.TransformPoint(new Vector3(0, -reelRadius, 0));
        }

        public void ResetRotation()
        {
            // 重置角度和角速度
            currentAngle = 0;
            angularVelocity = 0;
            transform.rotation = Quaternion.identity;
            UpdateOutletPosition();
        }

        /// <summary>遗留兼容（旧 CableSystem 场景仍在调用）。</summary>
        public void UpdateRotation()
        {
            if (cablePanel == null || cablePanel.PlugRef == null) return;
            UpdateRotation(true);
        }

        /// <summary>拖拽/插接中朝拉力方向施加扭矩；闲置时缓动回正。</summary>
        public void UpdateRotation(bool active, float tautness = 1f)
        {
            if (cablePanel == null || cablePanel.PlugRef == null) return;

            if (!active)
            {
                angularVelocity = 0f;
                currentAngle = Mathf.LerpAngle(currentAngle, 0f, returnSpeed * Time.deltaTime);
                ApplyRotation();
                return;
            }

            // 线缆还有余量时不驱动转盘，避免"还没拉紧就先转"
            if (tautness <= 0f)
            {
                angularVelocity *= Mathf.Exp(-angularDamping * Time.deltaTime);
                ApplyRotation();
                return;
            }

            Vector2 center = transform.position;
            Vector2 outlet = outletPos;
            Vector2 force = (Vector2)cablePanel.PlugRef.transform.position - outlet;
            Vector2 r = outlet - center;

            float torque = (r.x * force.y - r.y * force.x) * tautness;

            angularVelocity += torque * torqueStrength * Time.deltaTime;
            angularVelocity *= Mathf.Exp(-angularDamping * Time.deltaTime);

            currentAngle += angularVelocity * Time.deltaTime;
            currentAngle = Mathf.Clamp(currentAngle, -maxHalfAngle, maxHalfAngle);

            if (currentAngle <= -maxHalfAngle && angularVelocity < 0f) angularVelocity = 0f;
            if (currentAngle >= maxHalfAngle && angularVelocity > 0f) angularVelocity = 0f;

            ApplyRotation();
        }

        private void ApplyRotation()
        {
            transform.rotation = Quaternion.Euler(0, 0, currentAngle);
            UpdateOutletPosition();
        }
    }
}