// Type-safe formatting utilities

export function formatBytes(bytes: number, decimals = 1): string {
  if (!bytes || bytes < 0) return '0 B';

  const k = 1024;
  const sizes = ['B', 'KB', 'MB', 'GB', 'TB', 'PB'];
  const i = Math.floor(Math.log(bytes) / Math.log(k));

  return `${(bytes / Math.pow(k, i)).toFixed(decimals)} ${sizes[i]}`;
}

export function formatSpeed(bytesPerSecond: number, decimals = 0): string {
  if (!bytesPerSecond || bytesPerSecond < 0) return '0 B/s';
  return `${formatBytes(bytesPerSecond, decimals)}/s`;
}

export function formatUptime(seconds: number): string {
  if (!seconds || seconds < 0) return '0s';

  const days = Math.floor(seconds / 86400);
  const hours = Math.floor((seconds % 86400) / 3600);
  const minutes = Math.floor((seconds % 3600) / 60);

  if (days > 0) {
    return `${days}d ${hours}h`;
  } else if (hours > 0) {
    return `${hours}h ${minutes}m`;
  } else {
    return `${minutes}m`;
  }
}

export function formatAbsoluteTime(timestamp: number): string {
  if (!timestamp) return '';
  const date = new Date(timestamp);

  const months = [
    'Jan',
    'Feb',
    'Mar',
    'Apr',
    'May',
    'Jun',
    'Jul',
    'Aug',
    'Sep',
    'Oct',
    'Nov',
    'Dec',
  ];

  const month = months[date.getMonth()];
  const day = date.getDate();
  const hours = date.getHours().toString().padStart(2, '0');
  const minutes = date.getMinutes().toString().padStart(2, '0');

  return `${day} ${month} ${hours}:${minutes}`;
}

export function formatRelativeTime(timestamp: number): string {
  if (!timestamp) return '';

  const now = Date.now();
  const diffMs = now - timestamp;

  // Handle invalid or future timestamps
  if (isNaN(diffMs) || !isFinite(diffMs)) return '';
  if (diffMs < 0) return '0s ago'; // Future timestamp, treat as current

  const diffSeconds = Math.floor(diffMs / 1000);
  const diffMinutes = Math.floor(diffSeconds / 60);
  const diffHours = Math.floor(diffMinutes / 60);
  const diffDays = Math.floor(diffHours / 24);
  const diffMonths = Math.floor(diffDays / 30);
  const diffYears = Math.floor(diffDays / 365);

  if (diffSeconds < 60) {
    return `${diffSeconds}s ago`;
  } else if (diffMinutes < 60) {
    return diffMinutes === 1 ? '1 min ago' : `${diffMinutes} mins ago`;
  } else if (diffHours < 24) {
    return diffHours === 1 ? '1 hour ago' : `${diffHours} hours ago`;
  } else if (diffDays < 30) {
    return diffDays === 1 ? '1 day ago' : `${diffDays} days ago`;
  } else if (diffMonths < 12) {
    return diffMonths === 1 ? '1 month ago' : `${diffMonths} months ago`;
  } else {
    return diffYears === 1 ? '1 year ago' : `${diffYears} years ago`;
  }
}