using UnityEngine;

namespace AibisDream
{
    /// <summary>
    /// 矩形区域组件
    /// 用于划定一个矩形区域，并判断点是否在区域内
    /// </summary>
    public class BoxArea : MonoBehaviour
    {
        [Header("Box尺寸设置")]
        [SerializeField] private float width = 10f;
        [SerializeField] private float height = 10f;

        [Header("原点位置设置")]
        [Tooltip("设置(0,0)点在Box中的位置")]
        [SerializeField] private AnchorPoint anchorPoint = AnchorPoint.Center;

        /// <summary>
        /// Box的宽度
        /// </summary>
        public float Width
        {
            get => width;
            set => width = value;
        }

        /// <summary>
        /// Box的高度
        /// </summary>
        public float Height
        {
            get => height;
            set => height = value;
        }

        /// <summary>
        /// 锚点位置
        /// </summary>
        public AnchorPoint AnchorPoint
        {
            get => anchorPoint;
            set => anchorPoint = value;
        }

        /// <summary>
        /// 获取Box的世界坐标边界
        /// </summary>
        public Bounds WorldBounds
        {
            get
            {
                Vector3 center = GetWorldCenter();
                Vector3 size = new Vector3(width, height, 0f);
                return new Bounds(center, size);
            }
        }

        /// <summary>
        /// 获取Box的本地坐标边界
        /// </summary>
        public Rect LocalRect
        {
            get
            {
                Vector2 offset = GetAnchorOffset();
                return new Rect(offset.x, offset.y, width, height);
            }
        }

        /// <summary>
        /// 判断给定的世界坐标位置是否在Box内
        /// </summary>
        /// <param name="worldPosition">世界坐标位置</param>
        /// <returns>如果位置在Box内返回true，否则返回false</returns>
        public bool Contains(Vector3 worldPosition)
        {
            // 将世界坐标转换为本地坐标
            Vector3 localPosition = transform.InverseTransformPoint(worldPosition);
            
            // 获取本地坐标的矩形区域
            Rect rect = LocalRect;
            
            // 判断点是否在矩形内（只考虑X和Y轴，忽略Z轴）
            return rect.Contains(new Vector2(localPosition.x, localPosition.y));
        }

        /// <summary>
        /// 判断给定的本地坐标位置是否在Box内
        /// </summary>
        /// <param name="localPosition">本地坐标位置</param>
        /// <returns>如果位置在Box内返回true，否则返回false</returns>
        public bool ContainsLocal(Vector2 localPosition)
        {
            Rect rect = LocalRect;
            return rect.Contains(localPosition);
        }

        /// <summary>
        /// 获取Box的世界坐标中心点
        /// </summary>
        private Vector3 GetWorldCenter()
        {
            Vector2 anchorOffset = GetAnchorOffset();
            Vector3 localCenter = new Vector3(anchorOffset.x + width * 0.5f, anchorOffset.y + height * 0.5f, 0f);
            return transform.TransformPoint(localCenter);
        }

        /// <summary>
        /// 根据锚点位置获取偏移量
        /// </summary>
        private Vector2 GetAnchorOffset()
        {
            return anchorPoint switch
            {
                AnchorPoint.BottomLeft => new Vector2(0f, 0f),
                AnchorPoint.BottomCenter => new Vector2(-width * 0.5f, 0f),
                AnchorPoint.BottomRight => new Vector2(-width, 0f),
                AnchorPoint.CenterLeft => new Vector2(0f, -height * 0.5f),
                AnchorPoint.Center => new Vector2(-width * 0.5f, -height * 0.5f),
                AnchorPoint.CenterRight => new Vector2(-width, -height * 0.5f),
                AnchorPoint.TopLeft => new Vector2(0f, -height),
                AnchorPoint.TopCenter => new Vector2(-width * 0.5f, -height),
                AnchorPoint.TopRight => new Vector2(-width, -height),
                _ => new Vector2(-width * 0.5f, -height * 0.5f)
            };
        }

#if UNITY_EDITOR
        /// <summary>
        /// 在Scene视图中绘制Box边界（选中时）
        /// </summary>
        private void OnDrawGizmos()
        {
            // 保存原始颜色
            Color originalColor = Gizmos.color;
            
            // 设置Box边界颜色
            Gizmos.color = Color.cyan;
            
            // 获取Box的四个角点（世界坐标）
            Vector2 offset = GetAnchorOffset();
            Vector3[] corners = new Vector3[4]
            {
                transform.TransformPoint(new Vector3(offset.x, offset.y, 0f)),                    // 左下角
                transform.TransformPoint(new Vector3(offset.x + width, offset.y, 0f)),           // 右下角
                transform.TransformPoint(new Vector3(offset.x + width, offset.y + height, 0f)), // 右上角
                transform.TransformPoint(new Vector3(offset.x, offset.y + height, 0f))           // 左上角
            };
            
            // 绘制Box边界线
            for (int i = 0; i < 4; i++)
            {
                int next = (i + 1) % 4;
                Gizmos.DrawLine(corners[i], corners[next]);
            }
            
            // 绘制中心点标记
            Gizmos.color = Color.green;
            Vector3 center = GetWorldCenter();
            Gizmos.DrawWireSphere(center, 0.15f);
            
            // 恢复原始颜色
            Gizmos.color = originalColor;
        }
#endif
    }

    /// <summary>
    /// 锚点位置枚举
    /// 定义(0,0)点在Box中的位置
    /// </summary>
    public enum AnchorPoint
    {
        [Tooltip("左下角")]
        BottomLeft,
        [Tooltip("底部中心")]
        BottomCenter,
        [Tooltip("右下角")]
        BottomRight,
        [Tooltip("左侧中心")]
        CenterLeft,
        [Tooltip("中心")]
        Center,
        [Tooltip("右侧中心")]
        CenterRight,
        [Tooltip("左上角")]
        TopLeft,
        [Tooltip("顶部中心")]
        TopCenter,
        [Tooltip("右上角")]
        TopRight
    }
}