import { mkdir, stat, writeFile } from 'node:fs/promises';
import { dirname, join, resolve } from 'node:path';
import { fileURLToPath } from 'node:url';
import { BRAND } from '../src/store/constants';

/**
 * Mirror the store wordmark into public/images/brand/logo_footer.png.
 *
 * Source: the logo the site publishes for its footer (BRAND.logoSourceUrl, 637×220 PNG).
 * The storefront ships that file instead of hotlinking la-rose.by — public/index.html
 * points at BRAND.logoLocalPath — and this script keeps the local copy on disk.
 *
 * Idempotent: an existing non-empty file is kept; pass `--force` to re-download it
 * (the source is a static theme asset, so a plain re-run is a no-op).
 *
 *   pnpm fetch:logo             # download only when missing
 *   pnpm fetch:logo -- --force  # refresh the local copy
 *
 * The dev server also calls `ensureBrandLogo()` once at boot (scripts/dev-server.ts),
 * so a fresh checkout gets the logo without an extra manual step.
 */

const USER_AGENT =
  'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0 Safari/537.36 la-rose-seed/1.0';
const REQUEST_TIMEOUT_MS = 20_000;

const PUBLIC_DIR = fileURLToPath(new URL('../public', import.meta.url));

/** Absolute path of the local file served at BRAND.logoLocalPath. */
export const BRAND_LOGO_FILE = join(PUBLIC_DIR, ...BRAND.logoLocalPath.split('/').filter(Boolean));

export type BrandLogoStatus = 'kept' | 'downloaded';

/** Ensure the local logo copy is on disk; download it when missing (or when forced). */
export async function ensureBrandLogo(force = false): Promise<BrandLogoStatus> {
  if (!force) {
    const info = await stat(BRAND_LOGO_FILE).catch(() => null);
    if (info && info.size > 0) return 'kept';
  }

  const controller = new AbortController();
  const timer = setTimeout(() => controller.abort(), REQUEST_TIMEOUT_MS);
  try {
    const response = await fetch(BRAND.logoSourceUrl, {
      headers: { 'user-agent': USER_AGENT, accept: 'image/png,image/*;q=0.9,*/*;q=0.5' },
      redirect: 'follow',
      signal: controller.signal,
    });
    if (!response.ok) throw new Error(`HTTP ${response.status} ${response.statusText}`);
    const contentType = response.headers.get('content-type') ?? '';
    if (!contentType.startsWith('image/')) {
      throw new Error(`unexpected content-type "${contentType || 'none'}"`);
    }

    const bytes = Buffer.from(await response.arrayBuffer());
    if (bytes.length === 0) throw new Error('empty response body');

    await mkdir(dirname(BRAND_LOGO_FILE), { recursive: true });
    await writeFile(BRAND_LOGO_FILE, bytes);
    return 'downloaded';
  } finally {
    clearTimeout(timer);
  }
}

const isDirectRun =
  process.argv[1] !== undefined && resolve(process.argv[1]) === fileURLToPath(import.meta.url);

if (isDirectRun) {
  const status = await ensureBrandLogo(process.argv.includes('--force'));
  const kb = ((await stat(BRAND_LOGO_FILE)).size / 1024).toFixed(1);
  console.log(
    status === 'kept'
      ? `fetch-logo: kept ${BRAND.logoLocalPath} (${kb} kB)`
      : `fetch-logo: downloaded ${BRAND.logoLocalPath} (${kb} kB)`,
  );
}