using UnityEngine;

namespace _02.Scripts
{
    [ExecuteInEditMode]
    public class SpeedLines : MonoBehaviour
    {
        [SerializeField] private Shader shader;
        [SerializeField] private Texture texture;
        [SerializeField] private Color color = new(1,1,1,0.1f);
        
        [Range(0,1)]
        [SerializeField] private float width = 0.4f;
        [Range(0, 1)]
        [SerializeField] private float length = 0.42f;
        [Range(0, 100)]
        [SerializeField] private float lengthSpeed = 17;
        [Range(0, 1)]
        [SerializeField] private float density = 0.75f;
        
        private Material material;
        
        private static readonly int Color = Shader.PropertyToID("_Color");
        private static readonly int Width = Shader.PropertyToID("_Width");
        private static readonly int Length = Shader.PropertyToID("_Length");
        private static readonly int LengthSpeed = Shader.PropertyToID("_LengthSpeed");
        private static readonly int Density = Shader.PropertyToID("_Density");
        private static readonly int Fbm = Shader.PropertyToID("_FBM");

        private void Awake()
        {
            if (material) return;
            
            material = new Material(shader);
            material.SetTexture(Fbm, texture);
        }
    
        private void LateUpdate()
        {
            material.SetColor(Color, color);
            material.SetFloat(Width, width);
            material.SetFloat(Length, length);
            material.SetFloat(LengthSpeed, lengthSpeed);
            material.SetFloat(Density, density);
        }
    
        public void OnRenderObject()
        {
            material.SetPass(0);
            GL.PushMatrix();
            GL.LoadOrtho();
    
            GL.Begin(GL.QUADS);
            GL.TexCoord(new Vector3(0, 0, 0));
            GL.Vertex3(0, 0, 0);
            GL.TexCoord(new Vector3(0, 1, 0));
            GL.Vertex3(0, 1, 0);
            GL.TexCoord(new Vector3(1, 1, 0));
            GL.Vertex3(1, 1, 0);
            GL.TexCoord(new Vector3(1, 0, 0));
            GL.Vertex3(1, 0, 0);
            GL.End();
            GL.PopMatrix();
        }
    }
}