import { Shader } from "./lib/shader.js";
import { BasicPlane } from "./lib/basic-plane.js";
import { App } from "./lib/app.js";

const app = new App({ fov: 20 });
const gl = app.gl;

const shader = new Shader(app)
  .attach(
    gl.VERTEX_SHADER,
    `
      attribute vec4 aVertexPosition;
      attribute vec2 aTextureCoord;
      
      uniform mat4 uModelViewMatrix;
      uniform mat4 uProjectionMatrix;

      varying highp vec2 vTextureCoord;
      
      void main() {
        gl_Position = uProjectionMatrix * uModelViewMatrix * aVertexPosition;
        vTextureCoord = aTextureCoord;
      }
    `
  )
  .attach(
    gl.FRAGMENT_SHADER,
    `
      precision highp float;

      uniform float uTime;
      uniform float uSinTime;
      uniform float uCosTime;

      varying highp vec2 vTextureCoord;

      vec3 rgb2hsv(vec3 c) {
        vec4 K = vec4(0.0, -1.0 / 3.0, 2.0 / 3.0, -1.0);
        vec4 p = mix(vec4(c.bg, K.wz), vec4(c.gb, K.xy), step(c.b, c.g));
        vec4 q = mix(vec4(p.xyw, c.r), vec4(c.r, p.yzx), step(p.x, c.r));

        float d = q.x - min(q.w, q.y);
        float e = 1.0e-10;
        return vec3(abs(q.z + (q.w - q.y) / (6.0 * d + e)), d / (q.x + e), q.x);
      }

      vec3 hsv2rgb(vec3 c) {
        vec4 K = vec4(1.0, 2.0 / 3.0, 1.0 / 3.0, 3.0);
        vec3 p = abs(fract(c.xxx + K.xyz) * 6.0 - K.www);
        return c.z * mix(K.xxx, clamp(p - K.xxx, 0.0, 1.0), c.y);
      }

      void main() {
        vec3 hsv = rgb2hsv(vec3(vTextureCoord, 1.0));
        hsv.x += uTime * 0.0001;
        hsv.y = vTextureCoord.x;
        hsv.z = vTextureCoord.y;
        vec3 rgb = hsv2rgb(hsv);

        gl_FragColor = vec4(rgb, 1.0);
        gl_FragColor = clamp(gl_FragColor, 0.0, 1.0);
      }
    `
  )
  .link();

const plane = new BasicPlane(app);
plane.attachShader(shader);

app.loop();