import assert from 'node:assert/strict';
import test from 'node:test';
import { approximateDistanceM } from './featureGeometry.js';

test('approximate distance takes the short way round 180°', () => {
  // Lau Islands (-179.0) to Savusavu (179.33): about 178 km apart.
  const across = approximateDistanceM(-17.5, -179.0, -16.78, 179.33);
  assert.ok(across > 150_000 && across < 200_000, String(across));
  assert.equal(
    Math.round(approximateDistanceM(0, 179.9, 0, -179.9)),
    Math.round(approximateDistanceM(0, -0.1, 0, 0.1)),
  );
  // Away from 180° nothing changes.
  assert.equal(Math.round(approximateDistanceM(0, 0, 0, 1)), 111_320);
});