using UnityEngine;

/// <summary>
/// 音频空间控制器
/// 职责：管理 3D 空间音效和位置跟随，与播放逻辑解耦
/// </summary>
public class AudioSpatialController
{
    #region Fields
    
    private Transform _audioTransform;      // 音频对象的 Transform
    private GameObject _followTarget;       // 跟随的目标对象
    private AudioSource _audioSource;       // AudioSource 引用
    private bool _is3DEnabled;              // 是否启用 3D 音效
    
    #endregion
    
    #region Properties
    
    /// <summary>
    /// 是否启用 3D 音效
    /// </summary>
    public bool Is3DEnabled => _is3DEnabled;
    
    /// <summary>
    /// 当前跟随的目标
    /// </summary>
    public GameObject FollowTarget => _followTarget;
    
    /// <summary>
    /// 当前位置
    /// </summary>
    public Vector3 Position 
    {
        get => _audioTransform != null ? _audioTransform.position : Vector3.zero;
        set
        {
            if (_audioTransform != null)
                _audioTransform.position = value;
        }
    }
    
    #endregion
    
    #region Constructor
    
    /// <summary>
    /// 创建空间音频控制器
    /// </summary>
    /// <param name="audioTransform">音频对象的 Transform</param>
    /// <param name="audioSource">AudioSource 组件</param>
    public AudioSpatialController(Transform audioTransform, AudioSource audioSource)
    {
        _audioTransform = audioTransform;
        _audioSource = audioSource;
        _is3DEnabled = false;
    }
    
    #endregion
    
    #region Public Methods
    
    /// <summary>
    /// 启用 3D 空间音效
    /// </summary>
    /// <param name="maxDistance">最大听音距离</param>
    public void Enable3D(float maxDistance = 150f)
    {
        if (_audioSource == null)
            return;
            
        _audioSource.spatialBlend = 1f;
        _audioSource.dopplerLevel = 0f;
        _audioSource.rolloffMode = AudioRolloffMode.Linear;
        _audioSource.maxDistance = maxDistance;
        _is3DEnabled = true;
    }
    
    /// <summary>
    /// 禁用 3D 空间音效（改为 2D）
    /// </summary>
    public void Disable3D()
    {
        if (_audioSource == null)
            return;
            
        _audioSource.spatialBlend = 0f;
        _is3DEnabled = false;
    }
    
    /// <summary>
    /// 设置跟随目标（自动启用 3D）
    /// </summary>
    /// <param name="target">要跟随的目标对象，null 表示停止跟随</param>
    /// <param name="maxDistance">最大听音距离</param>
    public void SetFollowTarget(GameObject target, float maxDistance = 150f)
    {
        _followTarget = target;
        
        if (target != null)
        {
            // 有目标，启用 3D 并立即同步位置
            Enable3D(maxDistance);
            if (_audioTransform != null)
            {
                _audioTransform.position = target.transform.position;
            }
        }
        else
        {
            // 无目标，禁用 3D
            Disable3D();
        }
    }
    
    /// <summary>
    /// 设置静态位置（不跟随对象）
    /// </summary>
    /// <param name="position">世界坐标位置</param>
    /// <param name="enable3D">是否启用 3D 音效</param>
    /// <param name="maxDistance">最大听音距离</param>
    public void SetStaticPosition(Vector3 position, bool enable3D = true, float maxDistance = 150f)
    {
        _followTarget = null;
        
        if (_audioTransform != null)
        {
            _audioTransform.position = position;
        }
        
        if (enable3D)
        {
            Enable3D(maxDistance);
        }
        else
        {
            Disable3D();
        }
    }
    
    /// <summary>
    /// 更新位置跟随（在 Update 循环中调用）
    /// </summary>
    public void Update()
    {
        if (_followTarget != null && _audioTransform != null)
        {
            _audioTransform.position = _followTarget.transform.position;
        }
    }
    
    /// <summary>
    /// 重置到初始状态
    /// </summary>
    public void Reset()
    {
        _followTarget = null;
        Disable3D();
        
        if (_audioTransform != null)
        {
            _audioTransform.localPosition = Vector3.zero;
        }
    }
    
    /// <summary>
    /// 配置 3D 音效参数
    /// </summary>
    /// <param name="spatialBlend">空间混合度 (0=2D, 1=3D)</param>
    /// <param name="dopplerLevel">多普勒效应强度</param>
    /// <param name="rolloffMode">衰减模式</param>
    /// <param name="maxDistance">最大距离</param>
    /// <param name="minDistance">最小距离</param>
    public void Configure3D(
        float spatialBlend = 1f,
        float dopplerLevel = 0f,
        AudioRolloffMode rolloffMode = AudioRolloffMode.Linear,
        float maxDistance = 150f,
        float minDistance = 1f)
    {
        if (_audioSource == null)
            return;
            
        _audioSource.spatialBlend = Mathf.Clamp01(spatialBlend);
        _audioSource.dopplerLevel = Mathf.Max(0f, dopplerLevel);
        _audioSource.rolloffMode = rolloffMode;
        _audioSource.maxDistance = Mathf.Max(minDistance, maxDistance);
        _audioSource.minDistance = Mathf.Max(0f, minDistance);
        
        _is3DEnabled = spatialBlend > 0f;
    }
    
    #endregion
    
    #region Debug
    
    /// <summary>
    /// 获取调试信息
    /// </summary>
    public string GetDebugInfo()
    {
        string targetInfo = _followTarget != null ? _followTarget.name : "None";
        string posInfo = _audioTransform != null ? _audioTransform.position.ToString("F2") : "N/A";
        
        return $"SpatialController: 3D={_is3DEnabled}, " +
               $"Following={targetInfo}, " +
               $"Position={posInfo}, " +
               $"SpatialBlend={(_audioSource != null ? _audioSource.spatialBlend : 0f):F2}";
    }
    
    #endregion
}