import { ApiError, apiErrorCode } from '@/api/client';

/**
 * Цвет роли сервера приходит целым числом (0 — цвет не задан).
 * Возвращаем CSS-цвет или `null`, чтобы отрисовать нейтральную заглушку.
 */
export function roleColorHex(color: number): string | null {
  if (!Number.isFinite(color) || color <= 0) {
    return null;
  }
  const rgb = Math.trunc(color) & 0xffffff;
  return `#${rgb.toString(16).padStart(6, '0')}`;
}

export function formatBytes(bytes: number, locale = 'ru'): string {
  if (!Number.isFinite(bytes) || bytes < 0) {
    return '—';
  }
  const units = ['B', 'KB', 'MB', 'GB', 'TB'];
  let value = bytes;
  let unit = 0;
  while (value >= 1024 && unit < units.length - 1) {
    value /= 1024;
    unit += 1;
  }
  const formatted = new Intl.NumberFormat(locale, {
    maximumFractionDigits: value < 10 && unit > 0 ? 1 : 0,
  }).format(value);
  return `${formatted} ${units[unit]}`;
}

// instanceof is unreliable across module instances (aliases, lazy chunks),
// so the error shape is checked structurally as well.
function hasErrorCode(value: unknown): value is { code: string } {
  return (
    typeof value === 'object' &&
    value !== null &&
    typeof (value as { code?: unknown }).code === 'string'
  );
}

export function errorCode(error: unknown): string {
  // The code from the server error envelope wins: it survives serialization
  // boundaries where instanceof checks do not.
  const envelopeCode = apiErrorCode(error);
  if (envelopeCode !== null) {
    return envelopeCode;
  }
  if (error instanceof ApiError) {
    return error.code;
  }
  if (hasErrorCode(error)) {
    return error.code;
  }
  if (error instanceof Error && error.name === 'AbortError') {
    return 'network.aborted';
  }
  return 'network.unreachable';
}