/**
 * Ramp — Codels 3D model library
 * License: CC0-1.0 · Units: meters · Y-up · Front: +Z · Origin: center of the base (y = 0)
 * Triangles: 116 · Size (W × H × D): 2.08 × 1.54 × 4.01 m
 *
 * Usage:
 *   import { createRamp } from './ramp.js';
 *   
 *   const model = createRamp();
 *   model.position.set(0, 0, 0);
 *   scene.add(model);
 */
import * as THREE from 'three';

const deg = THREE.MathUtils.degToRad;

// Extrude a 2D outline along Z (centered). bevel = [thickness, size, segments].
function extrude(outline, depth, holes = [], bevel = null) {
  const shape = new THREE.Shape(outline.map(([x, y]) => new THREE.Vector2(x, y)));
  for (const hole of holes) shape.holes.push(new THREE.Path(hole.map(([x, y]) => new THREE.Vector2(x, y))));
  const options = bevel
    ? { depth, bevelEnabled: true, bevelThickness: bevel[0], bevelSize: bevel[1], bevelSegments: bevel[2] }
    : { depth, bevelEnabled: false };
  return new THREE.ExtrudeGeometry(shape, options).translate(0, 0, -depth / 2);
}

export function createRamp() {
  const root = new THREE.Group();
  root.name = 'Ramp';

  // Materials
  const bodyMat = new THREE.MeshStandardMaterial({ name: 'body', color: 0x4a8ee6, roughness: 0.6, flatShading: true });
  const trimMat = new THREE.MeshStandardMaterial({ name: 'trim', color: 0x305991, roughness: 0.6, flatShading: true });
  const stripeMat = new THREE.MeshStandardMaterial({ name: 'stripe', color: 0xffd23f, roughness: 0.5, flatShading: true });

  // Shared geometries
  const extrudeGeo = extrude([[-2, 0], [2.01, 0], [2.01, 1.54], [1.75, 1.54], [-2, 0.04]], 0.05);
  const boxGeo = new THREE.BoxGeometry(1.72, 0.02, 0.22);

  // Parts
  const wedge = new THREE.Mesh(extrude([[-2, 0], [2, 0], [2, 1.5], [1.75, 1.5]], 2), bodyMat);
  wedge.name = 'wedge';
  wedge.rotation.set(0, deg(90), 0);
  root.add(wedge);
  const railLeft = new THREE.Mesh(extrudeGeo, trimMat);
  railLeft.name = 'railLeft';
  railLeft.position.set(-1.015, 0, 0);
  railLeft.rotation.set(0, deg(90), 0);
  root.add(railLeft);
  const railRight = new THREE.Mesh(extrudeGeo, trimMat);
  railRight.name = 'railRight';
  railRight.position.set(1.015, 0, 0);
  railRight.rotation.set(0, deg(90), 0);
  root.add(railRight);
  const stripe1 = new THREE.Mesh(boxGeo, stripeMat);
  stripe1.name = 'stripe1';
  stripe1.position.set(0, 0.2234, 1.4576);
  stripe1.rotation.set(deg(21.8014), 0, 0);
  root.add(stripe1);
  const stripe2 = new THREE.Mesh(boxGeo, stripeMat);
  stripe2.name = 'stripe2';
  stripe2.position.set(0, 0.4363, 0.9255);
  stripe2.rotation.set(deg(21.8014), 0, 0);
  root.add(stripe2);
  const stripe3 = new THREE.Mesh(boxGeo, stripeMat);
  stripe3.name = 'stripe3';
  stripe3.position.set(0, 0.6491, 0.3933);
  stripe3.rotation.set(deg(21.8014), 0, 0);
  root.add(stripe3);
  const stripe4 = new THREE.Mesh(boxGeo, stripeMat);
  stripe4.name = 'stripe4';
  stripe4.position.set(0, 0.862, -0.1388);
  stripe4.rotation.set(deg(21.8014), 0, 0);
  root.add(stripe4);
  const stripe5 = new THREE.Mesh(boxGeo, stripeMat);
  stripe5.name = 'stripe5';
  stripe5.position.set(0, 1.0749, -0.671);
  stripe5.rotation.set(deg(21.8014), 0, 0);
  root.add(stripe5);
  const stripe6 = new THREE.Mesh(boxGeo, stripeMat);
  stripe6.name = 'stripe6';
  stripe6.position.set(0, 1.2877, -1.2032);
  stripe6.rotation.set(deg(21.8014), 0, 0);
  root.add(stripe6);

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

export default createRamp;