import { createHash } from 'crypto';
import fs from 'fs';
import path from 'path';
import { extractStyle } from '@ant-design/cssinjs';
import type Entity from '@ant-design/cssinjs/lib/Cache';

export type DoExtraStyleOptions = {
  cache: Entity;
  dir?: string;
  baseFileName?: string;
};
export function doExtraStyle({ cache, dir = 'antd-output', baseFileName = 'antd.min' }: DoExtraStyleOptions) {
  const baseDir = path.resolve(__dirname, '../../static/css');

  const outputCssPath = path.join(baseDir, dir);

  if (!fs.existsSync(outputCssPath)) {
    fs.mkdirSync(outputCssPath, { recursive: true });
  }

  const css = extractStyle(cache, true);
  if (!css) return '';

  const md5 = createHash('md5');
  const hash = md5.update(css).digest('hex');
  const fileName = `${baseFileName}.${hash.substring(0, 8)}.css`;
  const fullpath = path.join(outputCssPath, fileName);

  const res = `_next/static/css/${dir}/${fileName}`;

  if (fs.existsSync(fullpath)) return res;

  fs.writeFileSync(fullpath, css);

  return res;
}
