#!/usr/bin/env node
// sync-context — copy the Aesthetic Computer authoring guides into easel/context/.
//
// aesel tells the model how to write an AC piece by naming the repo's guides and
// asking it to read them. That works inside the monorepo and nowhere else: the
// lookup is existsSync against the working directory, so an installed aesel
// opened on someone's Desktop passes along no AC knowledge at all. It becomes a
// general-purpose editor that happens to publish to a URL.
//
// So the guides travel with the tool. They are 24 KB of markdown against 224 KB
// of source — a tenth of what is already being shipped — and they are the entire
// reason to install this rather than use the vendor CLI directly.
//
// Copies, not symlinks: a symlink does not survive an npm tarball or a curl
// install. Copies drift, so `npm test` fails when they do, and this script is
// how you fix it.
//
//   node bin/sync-context.mjs          # write the bundle
//   node bin/sync-context.mjs --check  # exit 1 if it is stale
import { readFileSync, writeFileSync, mkdirSync } from "node:fs";
import { dirname, join } from "node:path";
import { fileURLToPath } from "node:url";
import { build as buildApiMap } from "./build-api-map.mjs";

const HERE = dirname(fileURLToPath(import.meta.url));
const aesel = join(HERE, "..");
const REPO = join(aesel, "..");
const OUT = join(aesel, "context");

// What a model needs to write a piece, and nothing else. Deliberately not the
// whole repository: this is the knowledge that is about Aesthetic Computer
// rather than about this checkout.
export const BUNDLE = [
  ["aesel/SCORE.md", "score.md", "the aesel piece workflow"],
  ["aesel/ACCOUNT.md", "account.md", "the person's AC account from the terminal"],
  ["SCREEN.md", "screen.md", "how a piece draws on the AC canvas"],
  ["HAND.md", "hand.md", "how the code reads"],
  ["system/public/aesthetic.computer/disks/CLAUDE.md", "pieces.md", "the piece authoring guide"],
  ["kidlisp/README.md", "kidlisp.md", "the KidLisp language"],
];

const header = (from, subject) =>
  `<!-- ${subject}\n     Bundled with aesel from ${from} in the Aesthetic Computer repository.\n     Do not edit here — edit the source and run \`npm run context\`. -->\n\n`;

export function build() {
  mkdirSync(OUT, { recursive: true });
  const guides = BUNDLE.map(([from, to, subject]) => {
    const body = header(from, subject) + readFileSync(join(REPO, from), "utf8");
    return { path: join(OUT, to), body, from, to, subject };
  });
  // The API map travels the same way, for the same reason: it is read off the
  // runtime source, which an installed aesel does not have.
  guides.push({
    path: join(OUT, "api.json"),
    body: buildApiMap(),
    from: "system/public/aesthetic.computer/lib/{disk,graph,ui,num,geo}.mjs",
    to: "api.json",
    subject: "the piece API map",
  });
  for(const file of ["lib/cam-doll.mjs","lib/graph.mjs","lib/disk.mjs","lib/num.mjs","lib/geo.mjs","lib/ui.mjs","disks/camera.mjs","disks/1v1.mjs","disks/notepat.mjs","disks/blank.mjs"]){
    const to="reference/"+file,from="system/public/aesthetic.computer/"+file;
    guides.push({path:join(OUT,to),body:readFileSync(join(REPO,from),"utf8"),from,to});
  }
  return guides;
}

const check = process.argv.includes("--check");
let stale = 0;
for (const file of build()) {
  let current = "";
  try { current = readFileSync(file.path, "utf8"); } catch {}
  if (current === file.body) continue;
  stale += 1;
  if (check) {
    console.error(`stale: context/${file.to} no longer matches ${file.from}`);
  } else {
    mkdirSync(dirname(file.path),{recursive:true});
    writeFileSync(file.path, file.body);
    console.log(`wrote context/${file.to}  (${(file.body.length / 1024).toFixed(1)} KB)`);
  }
}

if (check && stale) {
  console.error(`\n${stale} file(s) stale — run \`npm run context\`.`);
  process.exit(1);
}
if (check) console.log("context bundle is current.");
else if (!stale) console.log("context bundle already current.");