micarrsim/tests/unit/camera.test.js

import {
  canonicalStringify,
  createResultDocument,
  estimateExperimentWorkload,
  hashSimulationInputs,
  shiftSceneDistance,
} from "/apps/acoustic-camera/model.js";
import { validateResult } from "/packages/contracts/validation.js";

function assertNear(actual, expected, tolerance, label) {
  assert(
    Math.abs(actual - expected) <= tolerance,
    `${label}: expected ${expected} ± ${tolerance}, received ${actual}`,
  );
}

test("Camera input hash is canonical across object key order", async () => {
  const first = {
    arrayDefinition: {
      id: "array",
      microphones: [
        { id: "mic-1", position: [0, 0, 0] },
        { id: "mic-2", position: [0.1, 0, 0] },
      ],
    },
    scene: {
      id: "scene",
      sampleRate: 8000,
      sources: [{ id: "source", position: [0, 0, 2], signal: { type: "tone", frequency: 1000 } }],
    },
    experiment: {
      id: "experiment",
      scan: { z: 2, columns: 8, rows: 8 },
      frequencyBands: [{ id: "band", minHz: 900, maxHz: 1100 }],
    },
  };
  const reordered = {
    experiment: {
      frequencyBands: [{ maxHz: 1100, minHz: 900, id: "band" }],
      scan: { rows: 8, columns: 8, z: 2 },
      id: "experiment",
    },
    scene: {
      sources: [{ signal: { frequency: 1000, type: "tone" }, position: [0, 0, 2], id: "source" }],
      sampleRate: 8000,
      id: "scene",
    },
    arrayDefinition: {
      microphones: [
        { position: [0, 0, 0], id: "mic-1" },
        { position: [0.1, 0, 0], id: "mic-2" },
      ],
      id: "array",
    },
  };

  assertEqual(canonicalStringify({ z: undefined, b: 2, a: { d: 4, c: 3 } }), '{"a":{"c":3,"d":4},"b":2}', "canonical JSON");
  const firstHash = await hashSimulationInputs(first);
  const reorderedHash = await hashSimulationInputs(reordered);
  assertEqual(firstHash, reorderedHash, "key ordering does not alter hash");
  assert(/^[a-f0-9]{64}$/.test(firstHash), "hash is lowercase SHA-256");

  reordered.scene.sources[0].position[0] = 0.01;
  const changedHash = await hashSimulationInputs(reordered);
  assert(changedHash !== firstHash, "semantic input change alters hash");
});

test("Camera workload counts unique overlapping FFT bins", () => {
  const arrayDefinition = {
    microphones: Array.from({ length: 3 }, (_, index) => ({ id: `mic-${index}`, position: [index, 0, 0] })),
  };
  const scene = { sampleRate: 8000, duration: 1 };
  const experiment = {
    scan: { columns: 10, rows: 8 },
    stft: { fftSize: 256, hopSize: 128 },
    frequencyBands: [
      { id: "lower", minHz: 100, maxHz: 200 },
      { id: "upper", minHz: 187.5, maxHz: 250 },
    ],
  };

  const workload = estimateExperimentWorkload(arrayDefinition, scene, experiment);
  assertEqual(workload.pointCount, 80, "scan point count");
  assertEqual(workload.microphoneCount, 3, "microphone count");
  assertEqual(workload.frameCount, 62, "STFT frame count");
  assertEqual(JSON.stringify(workload.bandBins), JSON.stringify([[4, 5, 6], [6, 7, 8]]), "bins per band");
  assertEqual(workload.selectedBinCount, 5, "overlapping bin is counted once");
  assertEqual(workload.complexMacCount, 74_400, "estimated complex MAC count");
  assertNear(workload.scalingVs50, 80 / 2500, 1e-15, "50x50 scaling");
  assertNear(workload.distanceMiB, (80 * 3 * 4) / 1024 ** 2, 1e-15, "distance table size");
});

test("Camera distance shift keeps the scene and scan on one z plane", () => {
  const scene = {
    sources: [
      { id: "one", position: [0.1, -0.2, 2] },
      { id: "two", position: [-0.3, 0.4, 2.5] },
    ],
    image: { plane: { z: 2, xMin: -1, xMax: 1, yMin: -1, yMax: 1 } },
  };
  const experiment = { scan: { z: 2 } };

  shiftSceneDistance(scene, experiment, 3.25);

  assertEqual(experiment.scan.z, 3.25, "scan z");
  assertEqual(scene.sources[0].position.join(","), "0.1,-0.2,3.25", "first source z shift");
  assertEqual(scene.sources[1].position.join(","), "-0.3,0.4,3.75", "relative source depth retained");
  assertEqual(scene.image.plane.z, 3.25, "background image plane z shift");
});

test("Camera result document is schema-safe and linked to its snapshot", async () => {
  const arrayDefinition = {
    id: "test-array",
    name: "Test array",
    microphones: [
      { id: "mic-1", position: [0, 0, 0] },
      { id: "mic-2", position: [0.1, 0, 0] },
    ],
  };
  const scene = {
    id: "test-scene",
    sources: [{ id: "source-1", position: [0, 0, 2] }],
  };
  const experiment = {
    id: "test-experiment",
    arrayId: arrayDefinition.id,
    sceneId: scene.id,
    scan: { rows: 2, columns: 2 },
    beamforming: { backend: "auto" },
    frequencyBands: [{ id: "band-1", color: "#65f2bf" }],
  };
  const run = {
    backend: "cpu",
    signalStats: { preNormalizationPeak: 0.75, appliedScale: 1, clippedSampleCount: 0 },
    timingMs: { total: 12.5, signalGeneration: 2.5, beamforming: 10 },
    fallback: { code: "webgpu-unavailable", message: "CPU fallback" },
    bands: [{
      id: "band-1",
      color: "#65f2bf",
      rawMap: Float32Array.of(0.1, 0.2, 0.3, 1),
      displayMap: Float32Array.of(0.1, 0.2, 0.3, 1),
      displayScale: "normalized",
    }],
  };
  const evaluations = new Map([["band-1", {
    peaks: [{ index: 3, sourceId: "source-1", position: [1, -1, 2], value: 1, localizationErrorM: 0.05 }],
    metrics: {
      peakToSidelobeDb: 10,
      energyInsideTruthRatio: 0.75,
      precision: 1,
      recall: 1,
      mainLobeWidthM: 0.2,
      ignoredNonFinite: Number.NaN,
    },
  }]]);

  const result = createResultDocument({
    arrayDefinition,
    scene,
    experiment,
    run,
    evaluations,
    inputHash: "a".repeat(64),
    createdAt: "2026-08-28T00:00:00.000Z",
  });

  assert(Array.isArray(result.bands[0].rawMap.values), "typed raw map becomes JSON array");
  assert(!("index" in result.bands[0].peaks[0]), "internal peak index is omitted");
  assertEqual(
    Object.keys(result.bands[0].metrics).join(","),
    "peakToSidelobeDb,energyInsideTruthRatio,precision,recall",
    "only finite schema metrics are exported",
  );
  assertEqual(result.environment.fallbackCode, "webgpu-unavailable", "fallback is recorded");

  const issues = await validateResult(result, { experiment, scene });
  assertEqual(issues.length, 0, `generated result validation: ${JSON.stringify(issues)}`);

  const wrongExperiment = { ...experiment, arrayId: "another-array" };
  const linkageIssues = await validateResult(result, { experiment: wrongExperiment, scene });
  assert(linkageIssues.some(({ path }) => path === "$.arrayId"), "validator catches snapshot linkage mismatch");
});