gemini-nexus/src/utils/account-status.ts

import { isString } from 'lodash-es';

export const RATE_LIMIT_HINTS = [
  'resource_exhausted',
  'too many requests',
  '429',
  'rate limit',
  'rate-limited',
  'risk control',
  'risk-controlled',
  'frozen',
] as const;

export const OAUTH_HINTS = [
  'unauthorized_client',
  'invalid_client',
  'invalid_grant',
  'oauth client',
  'not authorized',
  'token expired',
  'reauth',
  'verify your account',
  'further action is required',
  'validation required',
  'validation_url',
  'appeal_url',
] as const;

function includesAny(text: string, hints: readonly string[]): boolean {
  return hints.some((hint) => text.includes(hint));
}

export function isRateLimitReason(reason: string): boolean {
  return includesAny(reason.toLowerCase(), RATE_LIMIT_HINTS);
}

export function isOAuthReauthReason(reason: string): boolean {
  return includesAny(reason.toLowerCase(), OAUTH_HINTS);
}

export function extractErrorMessage(error: unknown): string {
  if (error instanceof Error) {
    return error.message;
  }
  if (isString(error)) {
    return error;
  }
  return String(error);
}

export function classifyAccountStatusFromError(
  error: unknown,
): { status: 'rate_limited' | 'expired'; reason: string } | null {
  const reason = extractErrorMessage(error).trim();
  if (!reason) {
    return null;
  }

  const normalizedReason = reason.toLowerCase();
  if (isRateLimitReason(normalizedReason)) {
    return { status: 'rate_limited', reason };
  }
  if (isOAuthReauthReason(normalizedReason)) {
    return { status: 'expired', reason };
  }

  if (normalizedReason.includes('forbidden')) {
    return { status: 'rate_limited', reason };
  }
  if (normalizedReason.includes('unauthorized')) {
    return { status: 'expired', reason };
  }

  return null;
}