using System;
using UnityEngine;
using UnityEngine.UI;

namespace JCUnityLib.UI
{
    [ExecuteAlways]
    [RequireComponent(typeof(Image))]
    public class RectBorder : MonoBehaviour 
    {
        const string _SHADER_NAME = "JC/UI/RectBorder";
        RectTransform _rectTransform;
        Image _image;
        public float borderRaduis = 20;  
        public RectBorderRadiusSwitch borderRadiusSwitch = new RectBorderRadiusSwitch(true, true, true, true);  
        public float borderWidth = 2;
        public Color borderColor = Color.black;

        void Update()
        {
            if (!_rectTransform) _rectTransform = GetComponent<RectTransform>();
            if (!_image) _image = GetComponent<Image>();
            if (_image.material == null || _image.material.shader.name != _SHADER_NAME) 
                _image.material = new Material(Shader.Find(_SHADER_NAME));
            Material imageMaterial = _image.material;
            if (!imageMaterial) return;
            imageMaterial.SetFloat("_NodeWidth", _rectTransform.rect.width);
            imageMaterial.SetFloat("_NodeHeight", _rectTransform.rect.height);
            imageMaterial.SetFloat("_BorderRadius", borderRaduis);
            imageMaterial.SetFloat("_BorderWidth", borderWidth);
            imageMaterial.SetColor("_BorderColor", borderColor);
            int borderRadiusSwitchVal = 0;
            if (borderRadiusSwitch.LeftTop) borderRadiusSwitchVal += 1;
            if (borderRadiusSwitch.RightTop) borderRadiusSwitchVal += 2;
            if (borderRadiusSwitch.RightBottom) borderRadiusSwitchVal += 4;
            if (borderRadiusSwitch.LeftBottom) borderRadiusSwitchVal += 8;
            imageMaterial.SetInt("_BorderRadiusSwitch", borderRadiusSwitchVal);
        }
    }
    [Serializable]
    public struct RectBorderRadiusSwitch
    {
        public bool LeftTop;
        public bool RightTop;
        public bool RightBottom;
        public bool LeftBottom;
        public RectBorderRadiusSwitch(bool lt = true, bool rt = true, bool rb = true, bool lb = true) 
        {
            LeftTop = lt;
            RightTop = rt;
            RightBottom = rb;
            LeftBottom = lb;
        }
    }
}