/**
 * Rabbit — Codels 3D model library
 * License: CC0-1.0 · Units: meters · Y-up · Front: +Z · Origin: center of the base (y = 0)
 * Triangles: 392 · Size (W × H × D): 0.28 × 0.60 × 0.42 m
 *
 * Usage:
 *   import { createRabbit } from './rabbit.js';
 *   
 *   const model = createRabbit();
 *   model.position.set(0, 0, 0);
 *   scene.add(model);
 */
import * as THREE from 'three';

const deg = THREE.MathUtils.degToRad;

// Deterministic vertex displacement (organic low-poly look).
function jitter(geometry, amount, seed) {
  const pos = geometry.attributes.position;
  const h = (a, b, c, s) => {
    let x = Math.imul(a, 73856093) ^ Math.imul(b, 19349663) ^ Math.imul(c, 83492791) ^ Math.imul(s, 2654435761);
    x = Math.imul(x ^ (x >>> 16), 2246822507);
    x = Math.imul(x ^ (x >>> 13), 3266489909);
    return ((x ^ (x >>> 16)) >>> 0) / 4294967295 - 0.5;
  };
  for (let i = 0; i < pos.count; i++) {
    const x = pos.getX(i), y = pos.getY(i), z = pos.getZ(i);
    const qx = Math.round(x * 1000), qy = Math.round(y * 1000), qz = Math.round(z * 1000);
    pos.setXYZ(i, x + h(qx, qy, qz, seed) * 2 * amount, y + h(qx, qy, qz, seed + 1) * 2 * amount, z + h(qx, qy, qz, seed + 2) * 2 * amount);
  }
  pos.needsUpdate = true;
  geometry.computeVertexNormals();
  return geometry;
}

export function createRabbit() {
  const root = new THREE.Group();
  root.name = 'Rabbit';

  // Materials
  const furMat = new THREE.MeshStandardMaterial({ name: 'fur', color: 0xbf8e64, roughness: 0.9, flatShading: true });
  const whiteMat = new THREE.MeshStandardMaterial({ name: 'white', color: 0xf6f0e6, roughness: 0.95, flatShading: true });
  const pinkMat = new THREE.MeshStandardMaterial({ name: 'pink', color: 0xf2a1b3, roughness: 0.6, flatShading: true });
  const eyeMat = new THREE.MeshStandardMaterial({ name: 'eye', color: 0x1b1617, roughness: 0.3, flatShading: true });
  const shineMat = new THREE.MeshStandardMaterial({ name: 'shine', color: 0xffffff, roughness: 0.3, flatShading: true });

  // Shared geometries
  const boxGeo = new THREE.BoxGeometry(0.075, 0.11, 0.15);
  const boxGeo2 = new THREE.BoxGeometry(0.07, 0.04, 0.17);
  const boxGeo3 = new THREE.BoxGeometry(0.074, 0.044, 0.035);
  const boxGeo4 = new THREE.BoxGeometry(0.05, 0.12, 0.05);
  const boxGeo5 = new THREE.BoxGeometry(0.055, 0.03, 0.065);
  const boxGeo6 = new THREE.BoxGeometry(0.034, 0.045, 0.01);
  const boxGeo7 = new THREE.BoxGeometry(0.013, 0.013, 0.006);
  const boxGeo8 = new THREE.BoxGeometry(0.03, 0.015, 0.006);
  const boxGeo9 = new THREE.BoxGeometry(0.06, 0.22, 0.032);
  const boxGeo10 = new THREE.BoxGeometry(0.034, 0.17, 0.01);

  // Parts
  const legBL = new THREE.Group();
  legBL.name = 'legBL';
  legBL.position.set(0.1, 0.12, -0.05);
  root.add(legBL);
  const haunchL = new THREE.Mesh(boxGeo, furMat);
  haunchL.name = 'haunchL';
  haunchL.position.set(0, -0.055, 0);
  legBL.add(haunchL);
  const hindFootL = new THREE.Mesh(boxGeo2, furMat);
  hindFootL.name = 'hindFootL';
  hindFootL.position.set(0, -0.1, 0.05);
  legBL.add(hindFootL);
  const toesL = new THREE.Mesh(boxGeo3, whiteMat);
  toesL.name = 'toesL';
  toesL.position.set(0, -0.1, 0.1195);
  legBL.add(toesL);
  const legBR = new THREE.Group();
  legBR.name = 'legBR';
  legBR.position.set(-0.1, 0.12, -0.05);
  root.add(legBR);
  const haunchR = new THREE.Mesh(boxGeo, furMat);
  haunchR.name = 'haunchR';
  haunchR.position.set(0, -0.055, 0);
  legBR.add(haunchR);
  const hindFootR = new THREE.Mesh(boxGeo2, furMat);
  hindFootR.name = 'hindFootR';
  hindFootR.position.set(0, -0.1, 0.05);
  legBR.add(hindFootR);
  const toesR = new THREE.Mesh(boxGeo3, whiteMat);
  toesR.name = 'toesR';
  toesR.position.set(0, -0.1, 0.1195);
  legBR.add(toesR);
  const legFL = new THREE.Group();
  legFL.name = 'legFL';
  legFL.position.set(0.055, 0.12, 0.085);
  root.add(legFL);
  const armL = new THREE.Mesh(boxGeo4, furMat);
  armL.name = 'armL';
  armL.position.set(0, -0.06, 0);
  legFL.add(armL);
  const pawL = new THREE.Mesh(boxGeo5, whiteMat);
  pawL.name = 'pawL';
  pawL.position.set(0, -0.105, 0.008);
  legFL.add(pawL);
  const legFR = new THREE.Group();
  legFR.name = 'legFR';
  legFR.position.set(-0.055, 0.12, 0.085);
  root.add(legFR);
  const armR = new THREE.Mesh(boxGeo4, furMat);
  armR.name = 'armR';
  armR.position.set(0, -0.06, 0);
  legFR.add(armR);
  const pawR = new THREE.Mesh(boxGeo5, whiteMat);
  pawR.name = 'pawR';
  pawR.position.set(0, -0.105, 0.008);
  legFR.add(pawR);
  const body = new THREE.Group();
  body.name = 'body';
  root.add(body);
  const torso = new THREE.Mesh(new THREE.BoxGeometry(0.2, 0.2, 0.24), furMat);
  torso.name = 'torso';
  torso.position.set(0, 0.125, -0.03);
  body.add(torso);
  const belly = new THREE.Mesh(new THREE.BoxGeometry(0.13, 0.15, 0.02), whiteMat);
  belly.name = 'belly';
  belly.position.set(0, 0.115, 0.094);
  body.add(belly);
  const tail = new THREE.Group();
  tail.name = 'tail';
  tail.position.set(0, 0.1, -0.16);
  root.add(tail);
  const cottonTail = new THREE.Mesh(jitter(new THREE.IcosahedronGeometry(0.05, 1), 0.008, 9), whiteMat);
  cottonTail.name = 'cottonTail';
  tail.add(cottonTail);
  const head = new THREE.Group();
  head.name = 'head';
  head.position.set(0, 0.215, 0.03);
  root.add(head);
  const skull = new THREE.Mesh(new THREE.BoxGeometry(0.23, 0.19, 0.19), furMat);
  skull.name = 'skull';
  skull.position.set(0, 0.08, 0.04);
  head.add(skull);
  const muzzle = new THREE.Mesh(new THREE.BoxGeometry(0.1, 0.06, 0.04), whiteMat);
  muzzle.name = 'muzzle';
  muzzle.position.set(0, 0.04, 0.15);
  head.add(muzzle);
  const nose = new THREE.Mesh(new THREE.BoxGeometry(0.035, 0.022, 0.015), pinkMat);
  nose.name = 'nose';
  nose.position.set(0, 0.064, 0.173);
  head.add(nose);
  const teeth = new THREE.Mesh(new THREE.BoxGeometry(0.024, 0.02, 0.01), shineMat);
  teeth.name = 'teeth';
  teeth.position.set(0, 0.002, 0.16);
  head.add(teeth);
  const eyeL = new THREE.Mesh(boxGeo6, eyeMat);
  eyeL.name = 'eyeL';
  eyeL.position.set(0.065, 0.1, 0.139);
  head.add(eyeL);
  const eyeShineL = new THREE.Mesh(boxGeo7, shineMat);
  eyeShineL.name = 'eyeShineL';
  eyeShineL.position.set(0.07, 0.112, 0.145);
  head.add(eyeShineL);
  const cheekL = new THREE.Mesh(boxGeo8, pinkMat);
  cheekL.name = 'cheekL';
  cheekL.position.set(0.085, 0.055, 0.137);
  head.add(cheekL);
  const eyeR = new THREE.Mesh(boxGeo6, eyeMat);
  eyeR.name = 'eyeR';
  eyeR.position.set(-0.065, 0.1, 0.139);
  head.add(eyeR);
  const eyeShineR = new THREE.Mesh(boxGeo7, shineMat);
  eyeShineR.name = 'eyeShineR';
  eyeShineR.position.set(-0.07, 0.112, 0.145);
  head.add(eyeShineR);
  const cheekR = new THREE.Mesh(boxGeo8, pinkMat);
  cheekR.name = 'cheekR';
  cheekR.position.set(-0.085, 0.055, 0.137);
  head.add(cheekR);
  const earL = new THREE.Group();
  earL.name = 'earL';
  earL.position.set(0.05, 0.165, 0.02);
  earL.rotation.set(deg(-6), 0, deg(-9));
  head.add(earL);
  const earFlapL = new THREE.Mesh(boxGeo9, furMat);
  earFlapL.name = 'earFlapL';
  earFlapL.position.set(0, 0.11, 0);
  earL.add(earFlapL);
  const earInnerL = new THREE.Mesh(boxGeo10, pinkMat);
  earInnerL.name = 'earInnerL';
  earInnerL.position.set(0, 0.11, 0.018);
  earL.add(earInnerL);
  const earR = new THREE.Group();
  earR.name = 'earR';
  earR.position.set(-0.05, 0.165, 0.02);
  earR.rotation.set(deg(-6), 0, deg(9));
  head.add(earR);
  const earFlapR = new THREE.Mesh(boxGeo9, furMat);
  earFlapR.name = 'earFlapR';
  earFlapR.position.set(0, 0.11, 0);
  earR.add(earFlapR);
  const earInnerR = new THREE.Mesh(boxGeo10, pinkMat);
  earInnerR.name = 'earInnerR';
  earInnerR.position.set(0, 0.11, 0.018);
  earR.add(earInnerR);

  root.traverse((o) => {
    if (o.isMesh) {
      o.castShadow = true;
      o.receiveShadow = true;
    }
  });
  return root;
}

export default createRabbit;