const GB = 1024 * 1024 * 1024;
const MB = 1024 * 1024;

export const formatBytes = (bytes: number): string => {
    if (bytes >= GB) return `${(bytes / GB).toFixed(1)} GB`;
    if (bytes >= MB) return `${(bytes / MB).toFixed(0)} MB`;
    return `${bytes} B`;
};

/**
 * Format an ETI version stamp (YYYYMMDD) for display. Falls back to the raw
 * string when it doesn't fit the expected shape.
 */
export const formatEtiVersion = (raw: string | undefined): string => {
    if (!raw) return '—';
    if (raw.length === 8 && /^\d{8}$/.test(raw)) {
        return `${raw.slice(0, 4)}.${raw.slice(4, 6)}.${raw.slice(6, 8)}`;
    }
    return raw;
};

export const formatPlayers = (max?: number): string => {
    if (!max || max <= 0) return '—';
    return max === 1 ? '1' : `1–${max}`;
};