#!/usr/bin/env node
/**
 * Mirror /design-system/ → /public/design-system/  AND  /src/styles/design-system/
 *
 * The canonical tokens live at the project root in design-system/. They need
 * to land in two places before the build runs:
 *
 *   • public/design-system/   — served as static assets so partner sites can
 *     `<link rel="stylesheet" href="https://nibiru-framework.com/design-system/tokens.css">`.
 *
 *   • src/styles/design-system/ — Starlight's `customCss` only accepts paths
 *     under src/, so the site itself imports the tokens from here.
 *
 * Both are copies of the same source. Rather than hand-maintain three trees,
 * this script syncs them on every install / build.
 */

import { mkdir, readdir, copyFile, stat, rm } from 'node:fs/promises';
import { dirname, join, resolve } from 'node:path';
import { fileURLToPath } from 'node:url';

const __dirname = dirname(fileURLToPath(import.meta.url));
const SRC = resolve(__dirname, '..', 'design-system');
const DSTS = [
	resolve(__dirname, '..', 'public', 'design-system'),
	resolve(__dirname, '..', 'src', 'styles', 'design-system'),
];

// Files we publish. Anything else (zips, internal notes) stays out of public/.
const PUBLISHED = new Set([
	'README.md',
	'tokens.css',
	'tokens.scss',
	'tokens.json',
	'tailwind.preset.js',
	'docs-page-mockup.html',
]);

async function ensure(dir) {
	await mkdir(dir, { recursive: true });
}

async function copyTree(src, dst) {
	await ensure(dst);
	const entries = await readdir(src, { withFileTypes: true });
	for (const entry of entries) {
		if (!PUBLISHED.has(entry.name)) continue;
		const from = join(src, entry.name);
		const to = join(dst, entry.name);
		if (entry.isDirectory()) {
			await copyTree(from, to);
		} else {
			await copyFile(from, to);
		}
	}
}

async function pruneStale(dst) {
	try {
		const entries = await readdir(dst, { withFileTypes: true });
		for (const entry of entries) {
			if (!PUBLISHED.has(entry.name)) {
				await rm(join(dst, entry.name), { recursive: true, force: true });
			}
		}
	} catch (err) {
		if (err.code !== 'ENOENT') throw err;
	}
}

try {
	await stat(SRC);
} catch {
	console.error(`[sync-design-system] no source directory at ${SRC}`);
	process.exit(1);
}

for (const dst of DSTS) {
	await pruneStale(dst);
	await copyTree(SRC, dst);
	console.log(`[sync-design-system] mirrored ${SRC} → ${dst}`);
}