import { existsSync } from 'node:fs';
import { basename, resolve } from 'node:path';

const CEM_CONFIG_FILENAMES = [
  'custom-elements-manifest.config.js',
  'custom-elements-manifest.config.mjs',
  'custom-elements-manifest.config.cjs',
  'custom-elements-manifest.config.ts',
];

/** Resolves the CEM config file in `cwd`. Shell globs like `config.*js` are unreliable on Windows. */
export function resolveCEMConfigPath(cwd: string): string | null {
  for (const name of CEM_CONFIG_FILENAMES) {
    const path = resolve(cwd, name);
    if (existsSync(path)) return path;
  }
  return null;
}

/** Returns the config filename for use with `cem analyze --config` when cwd is the package root. */
export function resolveCEMConfigArg(cwd: string): string | null {
  const path = resolveCEMConfigPath(cwd);
  return path ? basename(path) : null;
}