import { describe, it, expect } from 'vitest';
import { _test } from '../src/lib/pinball.js';

const { closestOnSeg, clamp } = _test;

describe('clamp', () => {
  it('bounds a value', () => {
    expect(clamp(5, 0, 10)).toBe(5);
    expect(clamp(-3, 0, 10)).toBe(0);
    expect(clamp(99, 0, 10)).toBe(10);
  });
});

describe('closestOnSeg', () => {
  it('projects onto the segment interior', () => {
    const [x, y, t] = closestOnSeg(5, 5, 0, 0, 10, 0);
    expect([x, y]).toEqual([5, 0]);
    expect(t).toBeCloseTo(0.5);
  });

  it('clamps to the endpoints', () => {
    expect(closestOnSeg(-4, 2, 0, 0, 10, 0).slice(0, 2)).toEqual([0, 0]);
    expect(closestOnSeg(20, -1, 0, 0, 10, 0).slice(0, 2)).toEqual([10, 0]);
  });

  it('handles a degenerate (zero-length) segment', () => {
    expect(closestOnSeg(3, 4, 1, 1, 1, 1).slice(0, 2)).toEqual([1, 1]);
  });
});