import * as THREE from 'three';
import { describe, expect, it } from 'vitest';
import { buildPier } from '../src/core/geometry';
import type { TerrainGrid } from '../src/core/ground-model';
import { buildPierScene } from '../src/view/scene';
import { loadP1 } from './helpers';

const model = buildPier(loadP1());

const terrain: TerrainGrid = { origin: [259815.676, 179088.094], step: 5, nx: 2, ny: 2, z: [30, 31, 32, 33] };

describe('지반 표시 (지형 모델이 없을 때)', () => {
  it('draws a thin square pad at the pier 지반고, side = coping length + 2 m', () => {
    const scene = buildPierScene(model);
    const mesh = scene.parts.ground.children[0] as THREE.Mesh;
    mesh.updateMatrixWorld(true);
    const pos = mesh.geometry.getAttribute('position');
    const pts: THREE.Vector3[] = [];
    for (let i = 0; i < pos.count; i++) pts.push(new THREE.Vector3().fromBufferAttribute(pos, i).applyMatrix4(mesh.matrixWorld));
    const top = Math.max(...pts.map((p) => p.y));
    const corners = pts.filter((p) => Math.abs(p.y - top) < 1e-6);
    // Four corners of the top face, with a distinct set of positions.
    const unique = corners.filter((p, i) => corners.findIndex((q) => q.distanceTo(p) < 1e-6) === i);
    expect(unique).toHaveLength(4);
    const side = model.copingL + 2;
    const edges = unique.flatMap((a, i) => unique.slice(i + 1).map((b) => a.distanceTo(b))).sort((a, b) => a - b);
    // Four sides of length `side`, two diagonals of length side·√2.
    for (const e of edges.slice(0, 4)) expect(e).toBeCloseTo(side, 3);
    for (const e of edges.slice(4)) expect(e).toBeCloseTo(side * Math.SQRT2, 3);
    // Thin: a pad, not a solid block. Centred on the ground EL.
    const box = new THREE.Box3().setFromObject(scene.parts.ground);
    expect(box.getSize(new THREE.Vector3()).y).toBeLessThan(0.1);
    expect(box.getCenter(new THREE.Vector3()).y).toBeCloseTo(model.groundEl, 2);
  });

  it('keeps the ground group out of the pier size', () => {
    const scene = buildPierScene(model);
    expect(scene.size).toBeLessThan(60);
  });

  it('does not draw the line when the terrain grid is present (the terrain replaces it)', () => {
    const scene = buildPierScene(model, terrain);
    expect(scene.parts.ground.children.length).toBe(1);
    const mesh = scene.parts.ground.children[0] as THREE.Mesh;
    expect(mesh.geometry.type).toBe('BufferGeometry');
  });
});