import assert from "node:assert/strict";
import fs from "node:fs";
import os from "node:os";
import path from "node:path";
import test from "node:test";
import { pthreadSidecar, artifactRevision, writeManifestIfChanged, missingArtifactPair, copyArtifactAtomically } from "./artifact-assets.mjs";

test("publishing a WASM leaves the old complete file visible until copying finishes", () => {
  const dir = fs.mkdtempSync(path.join(os.tmpdir(), "freecad-atomic-"));
  try {
    const source = path.join(dir, "source.wasm"), target = path.join(dir, "public.wasm");
    const previous = Buffer.from([0, 97, 115, 109, 1, 0, 0, 0]);
    const next = Buffer.concat([previous, Buffer.from([0, 2, 0, 1])]);
    fs.writeFileSync(source, next); fs.writeFileSync(target, previous);
    copyArtifactAtomically(source, target, (from, temporary) => {
      fs.writeFileSync(temporary, "partial");
      assert.deepEqual(fs.readFileSync(target), previous);
      fs.copyFileSync(from, temporary);
    });
    assert.deepEqual(fs.readFileSync(target), next);
    assert.throws(() => copyArtifactAtomically(source, target, (_from, temporary) => {
      fs.writeFileSync(temporary, "partial"); throw Error("interrupted copy");
    }), /interrupted copy/);
    assert.deepEqual(fs.readFileSync(target), next);
    fs.writeFileSync(source, next.subarray(0, next.length - 1));
    assert.throws(() => copyArtifactAtomically(source, target), /Incomplete or invalid WASM/);
    assert.deepEqual(fs.readFileSync(target), next);
    fs.writeFileSync(source, next);
    assert.throws(() => copyArtifactAtomically(source, target, (from, temporary) => {
      fs.copyFileSync(from, temporary); fs.appendFileSync(from, Buffer.from([0]));
    }), /changed while copying/);
    assert.deepEqual(fs.readFileSync(target), next);
    assert.deepEqual(fs.readdirSync(dir).sort(), ["public.wasm", "source.wasm"]);
  } finally { fs.rmSync(dir, { recursive: true, force: true }); }
});

test("an unfinished native link cannot publish a new WASM with an old loader", () => {
  const dir = fs.mkdtempSync(path.join(os.tmpdir(), "freecad-pair-"));
  try {
    const wasm = path.join(dir, "FreeCADWebDocumentProbe.wasm");
    const runtime = path.join(dir, "FreeCADWebDocumentProbe.js");
    fs.writeFileSync(wasm, "new wasm from incomplete link");
    assert.deepEqual(missingArtifactPair(wasm), [runtime]);
    fs.writeFileSync(runtime, "matching runtime");
    assert.deepEqual(missingArtifactPair(wasm), []);
    assert.deepEqual(missingArtifactPair(runtime), []);
    fs.unlinkSync(wasm);
    assert.deepEqual(missingArtifactPair(runtime), [wasm]);
    assert.deepEqual(missingArtifactPair(path.join(dir, "freecad-sample.step")), []);
  } finally { fs.rmSync(dir, { recursive: true, force: true }); }
});

test("thread worker follows its runtime from the same build directory", () => {
  const dir = fs.mkdtempSync(path.join(os.tmpdir(), "freecad-assets-"));
  try {
    const runtime = path.join(dir, "Probe.js");
    const destination = path.join(dir, "public/Probe.js");
    assert.equal(pthreadSidecar(runtime, destination), null);
    fs.writeFileSync(path.join(dir, "Probe.worker.js"), "thread worker");
    assert.deepEqual(pthreadSidecar(runtime, destination), [path.join(dir, "Probe.worker.js"), path.join(dir, "public/Probe.worker.js")]);
    assert.equal(pthreadSidecar(path.join(dir, "Probe.worker.js"), destination), null);
  } finally { fs.rmSync(dir, { recursive: true, force: true }); }
});

test("runtime, data and worker changes invalidate revisions independently of WASM", () => {
  const hashes = { runtime: "js1", wasm: "wasm", data: "data1", pthreadWorker: "worker1" };
  const revision = artifactRevision(hashes);
  for (const key of Object.keys(hashes)) assert.notEqual(artifactRevision({ ...hashes, [key]: "changed" }), revision);
  assert.equal(artifactRevision({ ...hashes }), revision);
});

test("unchanged manifest preserves contents and mtime across synchronization", () => {
  const dir = fs.mkdtempSync(path.join(os.tmpdir(), "freecad-manifest-"));
  try {
    const file = path.join(dir, "manifest.json");
    const value = { schema: "manifest/v1", generatedAt: "first", modules: { Draft: { revision: "one" } } };
    assert.equal(writeManifestIfChanged(file, value), true);
    const before = fs.statSync(file).mtimeNs ?? fs.statSync(file).mtimeMs;
    assert.equal(writeManifestIfChanged(file, { ...value, generatedAt: "second" }), false);
    assert.equal(fs.statSync(file).mtimeNs ?? fs.statSync(file).mtimeMs, before);
    assert.equal(JSON.parse(fs.readFileSync(file, "utf8")).generatedAt, "first");
    assert.equal(writeManifestIfChanged(file, { ...value, modules: { Draft: { revision: "two" } } }), true);
  } finally { fs.rmSync(dir, { recursive: true, force: true }); }
});