/* eslint-disable react-hooks/immutability */
"use client";

import React, { useRef, useMemo } from 'react';
import { Canvas, useFrame } from '@react-three/fiber';
import * as THREE from 'three';

const fragmentShader = `
uniform float u_time;
uniform float u_audio;
varying vec2 vUv;

// Perlin noise function
vec3 mod289(vec3 x) { return x - floor(x * (1.0 / 289.0)) * 289.0; }
vec2 mod289(vec2 x) { return x - floor(x * (1.0 / 289.0)) * 289.0; }
vec3 permute(vec3 x) { return mod289(((x*34.0)+1.0)*x); }
float snoise(vec2 v) {
  const vec4 C = vec4(0.211324865405187, 0.366025403784439, -0.577350269189626, 0.024390243902439);
  vec2 i  = floor(v + dot(v, C.yy) );
  vec2 x0 = v -   i + dot(i, C.xx);
  vec2 i1;
  i1 = (x0.x > x0.y) ? vec2(1.0, 0.0) : vec2(0.0, 1.0);
  vec4 x12 = x0.xyxy + C.xxzz;
  x12.xy -= i1;
  i = mod289(i);
  vec3 p = permute( permute( i.y + vec3(0.0, i1.y, 1.0 )) + i.x + vec3(0.0, i1.x, 1.0 ));
  vec3 m = max(0.5 - vec3(dot(x0,x0), dot(x12.xy,x12.xy), dot(x12.zw,x12.zw)), 0.0);
  m = m*m ;
  m = m*m ;
  vec3 x = 2.0 * fract(p * C.www) - 1.0;
  vec3 h = abs(x) - 0.5;
  vec3 ox = floor(x + 0.5);
  vec3 a0 = x - ox;
  m *= 1.79284291400159 - 0.85373472095314 * ( a0*a0 + h*h );
  vec3 g;
  g.x  = a0.x  * x0.x  + h.x  * x0.y;
  g.yz = a0.yz * x12.xz + h.yz * x12.yw;
  return 130.0 * dot(m, g);
}

void main() {
    vec2 pos = vUv * 2.0;
    
    // Create organic movement driven by time and audio
    float noise1 = snoise(pos + u_time * 0.2) * (1.0 + u_audio * 2.0);
    float noise2 = snoise(pos - u_time * 0.3 + noise1) * (1.0 + u_audio * 1.5);
    
    // Sapphire blue base colors
    vec3 color1 = vec3(0.0, 0.05, 0.15); // Deep dark blue
    vec3 color2 = vec3(0.0, 0.2, 0.5);   // Mid sapphire
    vec3 color3 = vec3(0.0, 0.5, 0.9);   // Bright sapphire highlight
    
    vec3 finalColor = mix(color1, color2, noise1 + 0.5);
    finalColor = mix(finalColor, color3, smoothstep(0.3, 1.0, noise2) * u_audio);
    
    gl_FragColor = vec4(finalColor, 1.0);
}
`;

const vertexShader = `
varying vec2 vUv;
void main() {
    vUv = uv;
    gl_Position = projectionMatrix * modelViewMatrix * vec4(position, 1.0);
}
`;

function FluidMesh({ audioRef }: { audioRef: React.MutableRefObject<number> }) {
  const meshRef = useRef<THREE.Mesh>(null);
  
  const uniforms = useMemo(() => ({
    u_time: { value: 0 },
    u_audio: { value: 0 },
  }), []);

  useFrame((state) => {
    uniforms.u_time.value = state.clock.elapsedTime;
    // Smooth the audio value to avoid jitter
    uniforms.u_audio.value += (audioRef.current - uniforms.u_audio.value) * 0.1;
  });

  return (
    <mesh ref={meshRef} position={[0, 0, 0]}>
      <planeGeometry args={[20, 20]} />
      <shaderMaterial
        fragmentShader={fragmentShader}
        vertexShader={vertexShader}
        uniforms={uniforms}
      />
    </mesh>
  );
}

export function QuantumFluidBackground({ audioRef }: { audioRef: React.MutableRefObject<number> }) {
  return (
    <div className="fixed inset-0 z-[-1] pointer-events-none bg-[#000510]">
      <Canvas camera={{ position: [0, 0, 1] }}>
        <FluidMesh audioRef={audioRef} />
      </Canvas>
    </div>
  );
}