import { mkdir, readFile, rm, writeFile } from 'node:fs/promises';
import path from 'node:path';

export interface StoredReconnectCredential {
  readonly projectName: string;
  readonly credential: string;
  readonly wsUrl: string;
  readonly updatedAt: string;
}

export function credentialFilePath(baseDir: string): string {
  return path.join(baseDir, 'local-agent-reconnect.json');
}

export async function loadReconnectCredential(baseDir: string): Promise<StoredReconnectCredential | undefined> {
  try {
    const raw = await readFile(credentialFilePath(baseDir), 'utf8');
    const parsed = JSON.parse(raw) as StoredReconnectCredential;
    if (!parsed?.projectName || !parsed?.credential || !parsed?.wsUrl) {
      return undefined;
    }
    return parsed;
  } catch {
    return undefined;
  }
}

export async function saveReconnectCredential(
  baseDir: string,
  value: StoredReconnectCredential,
): Promise<void> {
  await mkdir(baseDir, { recursive: true });
  await writeFile(credentialFilePath(baseDir), JSON.stringify(value, null, 2), 'utf8');
}

export async function clearReconnectCredential(baseDir: string): Promise<void> {
  try {
    await rm(credentialFilePath(baseDir));
  } catch {
    /* already absent */
  }
}