// Builds the installable draw.io plugin. Unlike the other reference plugins
// this one carries a bundled application: the official draw.io editor webapp
// (pinned release, fetched once into vendor/ — same pattern as the font
// build, deploy/fonts/build-fonts.mjs) ships as static assets and runs
// entirely inside the sandbox; the frame CSP pins every request to the
// plugin's own asset path, so nothing ever talks to diagrams.net.
import { execFileSync } from 'node:child_process';
import {
  existsSync,
  mkdirSync,
  readFileSync,
  readdirSync,
  rmSync,
  statSync,
  writeFileSync,
} from 'node:fs';
import { dirname, join, relative } from 'node:path';
import { fileURLToPath } from 'node:url';

import { build } from 'esbuild';
import { zipSync } from 'fflate';

const DRAWIO_VERSION = '30.3.6';
const DRAWIO_TARBALL = `https://github.com/jgraph/drawio/archive/refs/tags/v${DRAWIO_VERSION}.tar.gz`;

const root = dirname(fileURLToPath(import.meta.url));
const manifest = JSON.parse(readFileSync(join(root, 'manifest.json'), 'utf8'));
const vendor = join(root, 'vendor');
const webapp = join(vendor, `drawio-${DRAWIO_VERSION}`, 'src', 'main', 'webapp');

// --- 1. Fetch + unpack the pinned draw.io release (cached in vendor/) -----
// In CI the vendor fetch is skipped (network + 60 MB — the fonts-build
// lesson): the controller bundle still builds, only the installable ZIP
// needs a dev machine (or a pre-populated vendor/ cache).
if (!existsSync(webapp)) {
  if (process.env.CI) {
    console.log('CI: skipping draw.io vendor fetch — bundling plugin.js only, no ZIP');
    await bundleController();
    process.exit(0);
  }
  mkdirSync(vendor, { recursive: true });
  const tarball = join(vendor, `drawio-${DRAWIO_VERSION}.tar.gz`);
  if (!existsSync(tarball)) {
    console.log(`fetching draw.io v${DRAWIO_VERSION} …`);
    execFileSync('curl', ['-sfL', '-o', tarball, DRAWIO_TARBALL], { stdio: 'inherit' });
  }
  execFileSync('tar', ['-xzf', tarball, '-C', vendor, `drawio-${DRAWIO_VERSION}/src/main/webapp`], {
    stdio: 'inherit',
  });
}

// --- 2. Select the runtime subset -----------------------------------------
// Included: everything the production bootstrap chain and its lazy loaders
// reach. Excluded: dev sources (js/diagramly, js/grapheditor — app.min.js
// contains them), the embed.diagrams.net integrations bundle, standalone
// viewers, MathJax (math typesetting off), file templates, server-side
// leftovers, and the PWA service worker.
const EXCLUDE_TOP = new Set([
  'WEB-INF',
  'META-INF',
  'templates',
  'math4',
  'plugins',
  'service-worker.js',
  'service-worker.js.map',
  'workbox-05b6c01b.js',
  'workbox-05b6c01b.js.map',
  'manifest.json', // PWA manifest, collides with the plugin manifest anyway
]);
const EXCLUDE_JS = new Set([
  'integrate.min.js',
  'viewer.min.js',
  'viewer-static.min.js',
  'diagramly',
  'grapheditor',
  'embed.dev.js',
]);
// Editor UI languages shipped: keep the product languages + the fallback.
const RESOURCE_KEEP = new Set(['dia.txt', 'dia_de.txt']);

/** Recursively collect files below `dir` (absolute), applying the filters. */
function collect(dir, baseRel) {
  const files = {};
  for (const name of readdirSync(dir)) {
    const abs = join(dir, name);
    const rel = baseRel === '' ? name : `${baseRel}/${name}`;
    const top = rel.split('/')[0];
    if (baseRel === '' && EXCLUDE_TOP.has(name)) continue;
    if (top === 'js' && rel.split('/').length === 2 && EXCLUDE_JS.has(name)) continue;
    if (top === 'resources' && !RESOURCE_KEEP.has(name) && !statSync(abs).isDirectory()) continue;
    if (name.endsWith('.map')) continue;
    if (statSync(abs).isDirectory()) {
      Object.assign(files, collect(abs, rel));
    } else {
      files[rel] = readFileSync(abs);
    }
  }
  return files;
}

const drawioFiles = collect(webapp, '');

// --- 3. Bundle the plugin controller ---------------------------------------
async function bundleController() {
  mkdirSync(join(root, 'dist'), { recursive: true });
  await build({
    entryPoints: [join(root, 'src/plugin.ts')],
    bundle: true,
    format: 'esm',
    outfile: join(root, 'dist/plugin.js'),
    minify: true,
  });
}
await bundleController();

// --- 4. Pack the ZIP --------------------------------------------------------
const files = {
  'manifest.json': readFileSync(join(root, 'manifest.json')),
  'plugin.js': readFileSync(join(root, 'dist/plugin.js')),
};
for (const name of readdirSync(join(root, 'i18n'))) {
  files[`i18n/${name}`] = readFileSync(join(root, 'i18n', name));
}
for (const [rel, bytes] of Object.entries(drawioFiles)) {
  files[`assets/drawio/${rel}`] = bytes;
}

const target = join(root, 'dist', `${manifest.id}-${manifest.version}.zip`);
rmSync(target, { force: true });
writeFileSync(target, zipSync(files, { level: 6 }));
const unpacked = Object.values(files).reduce((sum, bytes) => sum + bytes.length, 0);
console.log(
  `wrote ${relative(process.cwd(), target)} ` +
    `(zip ${(statSync(target).size / 1024 / 1024).toFixed(1)} MiB, ` +
    `unpacked ${(unpacked / 1024 / 1024).toFixed(1)} MiB, ` +
    `${Object.keys(files).length} files)`,
);