import { describe, expect, it } from 'vitest';
import { decodeResult, digest, encodeResult } from '../src/sim/cache';
import type { SimResult } from '../src/sim/types';

describe('result cache encoding', () => {
  it('round-trips a result, optional arrays included', () => {
    const r: SimResult = {
      audio: new Float32Array([0.5, -1, 3]),
      fs: 48000,
      frames: new Float32Array(7).map((_, i) => i * 0.1),
      frameTimes: new Float64Array([0, 0.5]),
      energy: new Float64Array([1e-3, 2e-3]),
      balance: new Float64Array([0, 1e-12]),
      dt: 1e-6,
      stepsPerSample: 21,
      omegaMax: 12345.6,
      wallSeconds: 3.2,
      maxStretch: 0.01,
      contactForce: new Float32Array([0, 4, 2]),
      backend: 'CPU',
    };
    const bytes = encodeResult(r);
    expect(bytes.length % 8).toBe(0);
    const back = decodeResult(bytes.buffer);
    expect(back).toEqual(r);
    expect(back.frameTimes).toBeInstanceOf(Float64Array);
    expect(back.malletPos).toBeUndefined();
  });

  it('hashes inputs canonically: key order does not matter, values and array types do', async () => {
    const a = await digest({ x: 1, arr: new Float64Array([1, 2]), y: undefined });
    expect(await digest({ arr: new Float64Array([1, 2]), x: 1 })).toBe(a);
    expect(await digest({ x: 1, arr: new Float64Array([1, 2.0000001]) })).not.toBe(a);
    expect(await digest({ x: 1, arr: new Float32Array([1, 2]) })).not.toBe(a);
    expect(await digest({ x: 2, arr: new Float64Array([1, 2]) })).not.toBe(a);
  });
});