using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;

namespace JCUnityLib.UI
{
    [ExecuteAlways]
    [RequireComponent(typeof(Image))]
    public class ValidateJigsaw : MonoBehaviour
    {
        const string _SHADER_NAME = "JC/UI/ValidateJigsaw";
        RectTransform _rectTransform;
        Image _image;
        public Color gapColor = Color.black;
        public Color gapBorderColor = Color.white;
        public float gapBorderWidth = 0.5f;
        public float gapSize = 20;
        public Vector2 originalPosition = new Vector2(40, 40);
        public Vector2 currentPosition = new Vector2(10, 40);

        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.SetColor("_GapColor", gapColor);
            imageMaterial.SetColor("_GapBorderColor", gapBorderColor);
            imageMaterial.SetFloat("_GapBorderWidth", gapBorderWidth);
            imageMaterial.SetFloat("_GapSize", gapSize);
            imageMaterial.SetVector("_OriginalPosition", originalPosition);
            imageMaterial.SetVector("_CurrentPosition", currentPosition);
        }

        public void SetCurrentPositionByPercent(float value)
        {
            currentPosition.x = (_rectTransform.rect.width - gapSize) * value;
        }

        public void InitRandomPosition()
        {   
            if (!_rectTransform) _rectTransform = GetComponent<RectTransform>();
            float minX = _rectTransform.rect.width * 0.2f + gapSize;
            float maxX = _rectTransform.rect.width * 0.9f - gapSize;
            float minY = _rectTransform.rect.height * 0.1f;
            float maxY = _rectTransform.rect.height * 0.9f - gapSize;
            originalPosition.x = minX + (maxX - minX) * Random.value;
            originalPosition.y = minY + (maxY - minY) * Random.value;
            currentPosition.x = 0;
            currentPosition.y = originalPosition.y;
        }

        public bool IsFit()
        {
            if (!_rectTransform) _rectTransform = GetComponent<RectTransform>();
            return Mathf.Abs(currentPosition.x - originalPosition.x) / (_rectTransform.rect.width - gapSize) < 0.0125;
        }
    }
}