/* npm packages compiled natively: every program under tests/fixtures/npm/cases
 * (plus the commander fixtures in npm-cases.ts) builds with the default
 * static npm compile and runs against Node. A case matches Node (stdout and
 * exit status for every argv list, stderr when it opts in with
 * `// @stderr`) unless KNOWN records how it differs:
 *
 * - build: the compile refuses it with this diagnostic code;
 * - run: it compiles, and the program's output names this diagnostic code
 *   (a refusal deferred to the operation that reached it), for every argv
 *   list or for the listed `argvs`, while the other lists match Node;
 * - divergence: it runs but does not match Node yet. These run as expected
 *   failures, so a fix that makes one match fails here until KNOWN drops it.
 *
 * The fixture node_modules are committed test data. Binaries compile the
 * package sources at build time and read nothing from node_modules at run
 * time.
 */
import { execFile } from "node:child_process";
import { createHash } from "node:crypto";
import { globSync, mkdirSync, readFileSync } from "node:fs";
import { dirname, join } from "node:path";
import { promisify } from "node:util";
import { describe, expect, test } from "vitest";
import { compile } from "@scriptc/compiler";
import { npmCases, type NpmCase } from "./npm-cases.js";
import { shardSelect, shardSuffix } from "./shard.js";

const execFileAsync = promisify(execFile);
const repoRoot = join(import.meta.dirname, "../..");
const fixturesRoot = join(repoRoot, "tests/fixtures");
const cacheDir = join(repoRoot, "node_modules/.cache/scriptc-tests");
const sanitize = process.env["SCRIPTC_SAN"] === "1";

type Known = { build: string } | { run: string; argvs?: string[][] } | { divergence: string };

const KNOWN: Record<string, Known> = {
  "any-chaining": { build: "SC2003" },
  "assert-shims": { run: "SC1043" },
  "buffer-shims": { run: "SC2020" },
  "bytes-exit": { build: "SC2004" },
  "cjs-esm-named": { build: "SC2013" },
  "cjs-lexer-aligned": { build: "SC2013" },
  "commander-calc": { run: "SC1090", argvs: [["--help"]] },
  "commander-calc-async": { run: "SC1090", argvs: [["--help"]] },
  "create-require": { run: "SC1090" },
  "dotfolder": { run: "SC1090" },
  "dual-package-kinds": { build: "SC2013" },
  "dynamic-import": { build: "SC2012" },
  "dynamic-import-local": { build: "SC2012" },
  "esbuild-require": { build: "SC2013" },
  "esm-missing-default": { build: "SC1090" },
  "esm-missing-export": { build: "SC1090" },
  "fetch-destructure": { run: "SC1031" },
  "fs-shims": { run: "SC1101" },
  "import-refusal": { build: "SC2020" },
  "island-registry": { build: "SC2011" },
  "island-timers": {
    divergence:
      "Timeout handles are numbers (typeof) and lose their ref flag once fired or cleared",
  },
  "island-web-plumbing": { run: "SC2020" },
  "lazy-traps": { build: "SC2013" },
  "misc-shims": { run: "SC2020" },
  "namespace": { build: "SC1013" },
  "node24-async-events": { run: "SC2020" },
  "node24-commonjs-metadata": { run: "SC2020" },
  "node24-crypto-kdf": { run: "SC2020" },
  "node24-deep-equality": { run: "SC2020" },
  "node24-diagnostics-async": { run: "SC1090" },
  "node24-diagnostics-tracing": { run: "SC1090" },
  "node24-env": { run: "SC1090" },
  "node24-esm-metadata": { run: "SC1090" },
  "node24-event-emitter": { run: "SC2020" },
  "node24-file-url-conversion": { build: "SC1090" },
  "node24-fs-descriptors": { run: "SC1090" },
  "node24-mime": { run: "SC2020" },
  "node24-mime-errors": { run: "SC1090" },
  "node24-no-error-assertions": { run: "SC2020" },
  "node24-parseargs": { run: "SC1090" },
  "node24-promise-timers": { run: "SC2020" },
  "node24-string-decoder": { run: "SC2020" },
  "node24-style-text": { run: "SC2020" },
  "node24-system-errors": { run: "SC1090" },
  "node24-text-encoding": { run: "SC2020" },
  "node24-text-utilities": { run: "SC2020" },
  "node24-timers-unref": { run: "SC2020" },
  "node24-url-factories": { run: "SC2020" },
  "node24-url-mutation": { run: "SC1090" },
  "node24-util-adapters": { run: "Object.create with this value is not supported yet" },
  "node24-util-types": { run: "SC1090" },
  "node24-web-stream-encoding": { run: "SC1090" },
  "node24-web-stream-errors": { run: "SC1090" },
  "node24-web-stream-lifecycle": { run: "SC1090" },
  "node24-web-stream-pipe-abort": { run: "SC2020" },
  "node24-web-stream-pipe-errors": { run: "SC1090" },
  "node24-web-stream-pipes": { run: "SC1090" },
  "node24-web-stream-queues": { run: "SC1090" },
  "node24-web-stream-readable-lifecycle": { run: "SC2020" },
  "node24-web-stream-readers": { run: "SC1090" },
  "node24-web-stream-tee": { run: "SC2020" },
  "node24-web-stream-transforms": { run: "SC1090" },
  "package-imports": { build: "SC2013" },
  "promise-bridge": { build: "SC1090" },
  "self-name": { build: "SC2013" },
  "stream-shims": { run: "SC1090" },
  "util-shims": { run: "SC2020" },
  "web-streams": { run: "SC1090" },
  "workspace-copied": { build: "SC2013" },
  "workspace-unclean": { build: "SC2013" },
};

const cases = shardSelect(npmCases(fixturesRoot), (c) => c.name);

/** Per-case timeouts past the default 120 s: the undici cases compile the
 * built-in undici implementation's module graph, which a sanitized build
 * on a CI runner takes minutes to compile. */
const TIMEOUTS: Record<string, number> = { undici5: 600_000, undici7: 600_000 };

interface RunResult {
  stdout: Buffer;
  stderr: Buffer;
  exitCode: number;
}

function programStderr(stderr: Buffer): Buffer {
  if (!sanitize) return stderr;
  // Linux ASan emits this instrumentation warning at the first fiber swap.
  // Latin-1 preserves every other byte, including non-UTF-8 program output.
  return Buffer.from(
    stderr
      .toString("latin1")
      .replace(
        /^==\d+==WARNING: ASan doesn't fully support makecontext\/swapcontext functions and may produce false positives in some cases!\n/gm,
        "",
      ),
    "latin1",
  );
}

async function runBinary(cmd: string, args: string[], cwd: string): Promise<RunResult> {
  try {
    // stdin closes immediately, as in differential.test.ts: a program that
    // reads fd 0 to EOF must not hang on an open pipe.
    const pending = execFileAsync(cmd, args, { cwd, encoding: "buffer" });
    pending.child.stdin?.end();
    const { stdout, stderr } = await pending;
    return { stdout, stderr, exitCode: 0 };
  } catch (err) {
    const e = err as { code?: unknown; signal?: unknown; stdout?: Buffer; stderr?: Buffer };
    if (!Buffer.isBuffer(e.stdout) || !Buffer.isBuffer(e.stderr)) throw err;
    const exitCode = typeof e.code === "number" ? e.code : -1;
    if (exitCode === -1 && typeof e.signal !== "string") throw err;
    return { stdout: e.stdout, stderr: e.stderr, exitCode };
  }
}

type Built = { ok: true; binary: string } | { ok: false; codes: string[]; text: string };

/** Compile once per (entry, lane); the cache key hashes the program and the
 * fixture packages so edits to either rebuild. */
async function build(entry: string): Promise<Built> {
  const hash = createHash("sha256");
  const inputs = [
    entry,
    ...globSync(join(dirname(entry), "*.{ts,mts,cts,js,mjs,cjs,json}")),
    ...globSync(join(fixturesRoot, "npm/node_modules/**/*.{js,mjs,cjs,json,d.ts,node}")),
  ].sort();
  for (const f of inputs) hash.update(f).update(readFileSync(f));
  const key = hash
    .update(sanitize ? "san" : "plain")
    .digest("hex")
    .slice(0, 16);
  const outDir = join(cacheDir, `npm-${key}`);
  mkdirSync(outDir, { recursive: true });
  const result = await compile(entry, { outPath: join(outDir, "program"), outDir, sanitize });
  if (result.ok) return { ok: true, binary: result.binaryPath };
  return {
    ok: false,
    codes: result.diagnostics.map((d) => d.code),
    text: result.diagnostics.map((d) => `${d.code}: ${d.message}`).join("\n"),
  };
}

async function expectMatchesNode(c: NpmCase, binary: string): Promise<void> {
  const cwd = dirname(c.entry);
  for (const argv of c.argvs ?? [[]]) {
    const [nodeRes, nativeRes] = await Promise.all([
      runBinary(process.execPath, [c.entry, ...argv], cwd),
      runBinary(binary, argv, cwd),
    ]);
    const label = argv.join(" ");
    if (!nodeRes.stdout.equals(nativeRes.stdout)) {
      expect(nativeRes.stdout.toString("utf8"), label).toBe(nodeRes.stdout.toString("utf8"));
      expect.unreachable("stdout differed at byte level but not after utf8 decode");
    }
    expect(nativeRes.exitCode, label).toBe(nodeRes.exitCode);
    if (c.compareStderr) expect(programStderr(nativeRes.stderr), label).toEqual(nodeRes.stderr);
  }
}

test("every KNOWN entry names a case", () => {
  const names = new Set(npmCases(fixturesRoot).map((c) => c.name));
  expect(Object.keys(KNOWN).filter((name) => !names.has(name))).toEqual([]);
});

describe(`npm native (${cases.length} programs${sanitize ? ", sanitized" : ""}${shardSuffix()})`, () => {
  for (const c of cases) {
    const known = KNOWN[c.name];
    if (known !== undefined && "divergence" in known) {
      test.fails(`${c.name} (diverges: ${known.divergence})`, async () => {
        const built = await build(c.entry);
        if (!built.ok) throw new Error(built.text);
        await expectMatchesNode(c, built.binary);
      }, 120_000);
      continue;
    }
    test(
      c.name,
      async () => {
        const built = await build(c.entry);
        if (known !== undefined && "build" in known) {
          expect(built.ok, "the compile refuses the program").toBe(false);
          if (!built.ok) expect(built.codes, built.text).toContain(known.build);
          return;
        }
        if (!built.ok) throw new Error(`npm fixture failed to compile:\n${built.text}`);
        if (known !== undefined && "run" in known) {
          for (const argv of known.argvs ?? c.argvs ?? [[]]) {
            const res = await runBinary(built.binary, argv, dirname(c.entry));
            const output = res.stdout.toString("utf8") + res.stderr.toString("utf8");
            expect(output, `${argv.join(" ")}: the deferred refusal`).toContain(known.run);
          }
          if (known.argvs === undefined) return;
          const refused = new Set(known.argvs.map((argv) => JSON.stringify(argv)));
          const argvs = (c.argvs ?? [[]]).filter((argv) => !refused.has(JSON.stringify(argv)));
          await expectMatchesNode({ ...c, argvs }, built.binary);
          return;
        }
        await expectMatchesNode(c, built.binary);
      },
      TIMEOUTS[c.name] ?? 120_000,
    );
  }
});