using UnityEngine;

namespace TyphoonUI
{
    /// <summary>
    /// 拓展一些2D相关的API
    /// </summary>
    internal static class Math2DExtension
    {
        public static Vector2 Abs(this Vector2 vector)
        {
            for (int i = 0; i < 2; ++i) vector[i] = Mathf.Abs(vector[i]);
            return vector;
        }

        public static Vector2 DividedBy(this Vector2 vector, Vector2 divisor)
        {
            for (int i = 0; i < 2; ++i) vector[i] /= divisor[i];
            return vector;
        }

        public static Vector2 Max(this Rect rect)
        {
            return new Vector2(rect.xMax, rect.yMax);
        }

        public static Vector2 IntersectionWithRayFromCenter(this Rect rect, Vector2 pointOnRay)
        {
            Vector2 pointOnRay_local = pointOnRay - rect.center;
            Vector2 edgeToRayRatios = (rect.Max() - rect.center).DividedBy(pointOnRay_local.Abs());
            return (edgeToRayRatios.x < edgeToRayRatios.y)
                ? new Vector2(pointOnRay_local.x > 0 ? rect.xMax : rect.xMin,
                    pointOnRay_local.y * edgeToRayRatios.x + rect.center.y)
                : new Vector2(pointOnRay_local.x * edgeToRayRatios.y + rect.center.x,
                    pointOnRay_local.y > 0 ? rect.yMax : rect.yMin);
        }
        
        
     
        
    }
}