export interface FilesystemRetryOptions {
  retryDelaysMs?: readonly number[];
  wait?: (delayMs: number) => void;
}

const DEFAULT_RETRY_DELAYS_MS = [100, 300, 900] as const;
const TRANSIENT_FILESYSTEM_ERROR_CODES = new Set([
  'EIO',
  'EPERM',
  'EBUSY',
  'EACCES',
]);

function waitSynchronously(delayMs: number): void {
  const signal = new Int32Array(new SharedArrayBuffer(Int32Array.BYTES_PER_ELEMENT));
  Atomics.wait(signal, 0, 0, delayMs);
}

export function retryTransientFilesystemOperation<T>(
  operation: () => T,
  options: FilesystemRetryOptions = {},
): T {
  const retryDelaysMs = options.retryDelaysMs ?? DEFAULT_RETRY_DELAYS_MS;
  const wait = options.wait ?? waitSynchronously;

  for (let attempt = 0; ; attempt += 1) {
    try {
      return operation();
    } catch (error) {
      const code = error && typeof error === 'object' && 'code' in error
        ? String(error.code)
        : '';
      const delayMs = retryDelaysMs[attempt];
      if (!TRANSIENT_FILESYSTEM_ERROR_CODES.has(code) || delayMs === undefined) {
        throw error;
      }
      wait(delayMs);
    }
  }
}