import assert from 'node:assert/strict';
import test from 'node:test';
import { readFileSync } from 'node:fs';
import { BoxGeometry, Group, Mesh, MeshStandardMaterial, Vector3 } from 'three';
import { createSummitMarker } from '../src/scene/summitMarker.ts';

test('exported marker embeds the current baked textures, not stale packed images', () => {
  const glb = readFileSync(new URL('../public/models/summit/summit-marker.glb', import.meta.url));
  const jsonLength = glb.readUInt32LE(12);
  const document = JSON.parse(glb.subarray(20, 20 + jsonLength).toString());
  const binaryStart = 28 + jsonLength;
  assert.equal(document.images.length, 4);
  for (const image of document.images) {
    const view = document.bufferViews[image.bufferView];
    const start = binaryStart + (view.byteOffset ?? 0);
    const embedded = glb.subarray(start, start + view.byteLength);
    const source = readFileSync(new URL(`../public/terrain/materials/${image.name}.png`, import.meta.url));
    assert.ok(embedded.equals(source), `${image.name} must match the latest bake`);
  }
});

test('marker seats its foot on sloping bedrock without deforming the stone', () => {
  const asset = new Group();
  const mesh = new Mesh(new BoxGeometry(4, 4, 2), new MeshStandardMaterial());
  mesh.position.y = 2;
  asset.add(mesh);
  const groundAt = (x: number, z: number) => 12 + .3*x - .2*z;
  const rock = new MeshStandardMaterial();
  const marker = createSummitMarker(asset, {x:0,z:0}, groundAt, rock);
  marker.group.updateMatrixWorld(true);
  const position = mesh.geometry.getAttribute('position');
  const point = new Vector3();
  let nearestContact = Infinity;
  for (let i=0; i<position.count; i++) {
    point.fromBufferAttribute(position,i).applyMatrix4(mesh.matrixWorld);
    if (position.getY(i)<0) {
      const burial = groundAt(point.x,point.z)-point.y;
      assert.ok(burial > .05, `base must stay below terrain: ${burial}`);
      assert.equal(position.getY(i),-2,'base geometry remains unchanged');
      nearestContact = Math.min(nearestContact,burial);
    } else {
      assert.equal(position.getY(i),2,'upper geometry remains unchanged');
    }
  }
  assert.ok(nearestContact < .3,'the stone is seated close to its lowest contact');
  marker.dispose();
  rock.dispose();
});