import { RnExecutorchErrorCode } from './ErrorCodes';

/**
 * Custom error class for React Native ExecuTorch errors.
 */
export class RnExecutorchError extends Error {
  /**
   * The error code representing the type of error.
   */
  public code: RnExecutorchErrorCode;

  /**
   * The original cause of the error, if any.
   */
  public cause?: unknown;

  constructor(code: number, message: string, cause?: unknown) {
    super(message);
    /**
     * The error code representing the type of error.
     */
    this.code = code;

    /**
     * The message describing the error.
     */
    this.message = message;

    /**
     * The original cause of the error, if any.
     */
    this.cause = cause;
  }
}

function isRnExecutorchErrorLike(
  e: unknown
): e is { code: number; message: string } {
  const candidate = e as Record<string, unknown>;

  return (
    typeof e === 'object' &&
    e !== null &&
    typeof candidate.code === 'number' &&
    typeof candidate.message === 'string'
  );
}

export function parseUnknownError(e: unknown): RnExecutorchError {
  if (e instanceof RnExecutorchError) {
    return e;
  }
  if (isRnExecutorchErrorLike(e)) {
    return new RnExecutorchError(e.code, e.message);
  }

  if (e instanceof Error) {
    return new RnExecutorchError(RnExecutorchErrorCode.Internal, e.message, e);
  }

  if (typeof e === 'string') {
    return new RnExecutorchError(RnExecutorchErrorCode.Internal, e);
  }

  return new RnExecutorchError(RnExecutorchErrorCode.Internal, String(e));
}