// Builds the extension into dist/: bundles the TypeScript entry points with
// esbuild and copies the static assets (manifest, popup HTML, CSS, icons).
// Run `node scripts/build.mjs` for a one-shot build, or with `--watch` for dev.
import * as esbuild from 'esbuild';
import { cp, mkdir, rm } from 'node:fs/promises';
import { existsSync } from 'node:fs';
import path from 'node:path';
import { fileURLToPath } from 'node:url';

const root = path.resolve(path.dirname(fileURLToPath(import.meta.url)), '..');
const dist = path.join(root, 'dist');
const watch = process.argv.includes('--watch');

/** Copy a file or directory from a repo-relative path into dist/ (flattened). */
async function copy(from, to) {
  const src = path.join(root, from);
  if (!existsSync(src)) return;
  await cp(src, path.join(dist, to), { recursive: true });
}

async function copyStatic() {
  await copy('src/manifest.json', 'manifest.json');
  await copy('src/popup/popup.html', 'popup.html');
  await copy('src/styles/diff.css', 'diff.css');
  await copy('src/styles/hljs-theme.css', 'hljs-theme.css');
  await copy('src/styles/popup.css', 'popup.css');
  await copy('icons', 'icons');
}

const options = {
  entryPoints: {
    content: path.join(root, 'src/content.ts'),
    background: path.join(root, 'src/background.ts'),
    popup: path.join(root, 'src/popup/popup.ts'),
  },
  outdir: dist,
  entryNames: '[name]',
  bundle: true,
  format: 'iife',
  target: ['chrome120'],
  minify: !watch,
  sourcemap: watch ? 'inline' : false,
  logLevel: 'info',
};

await rm(dist, { recursive: true, force: true });
await mkdir(dist, { recursive: true });
await copyStatic();

if (watch) {
  const ctx = await esbuild.context(options);
  await ctx.watch();
  console.log('watching for changes…');
} else {
  await esbuild.build(options);
  console.log('built ->', path.relative(root, dist));
}