frontend/src/lib/utils.ts

import { type ClassValue, clsx } from "clsx";
import { twMerge } from "tailwind-merge";

export function cn(...inputs: ClassValue[]) {
  return twMerge(clsx(inputs));
}

export function formatFileSize(bytes: number): string {
  if (bytes === 0) return "0 Bytes";
  const k = 1024;
  const sizes = ["Bytes", "KB", "MB", "GB"];
  const i = Math.floor(Math.log(bytes) / Math.log(k));
  return parseFloat((bytes / Math.pow(k, i)).toFixed(2)) + " " + sizes[i];
}

export function formatTimestamp(timestamp: string): string {
  return new Date(timestamp).toLocaleString();
}

export function formatRelativeTime(dateString: string): string {
  const date = new Date(dateString);
  const now = new Date();
  const diffInSeconds = Math.floor((now.getTime() - date.getTime()) / 1000);

  if (diffInSeconds < 60) {
    return "just now";
  }

  const diffInMinutes = Math.floor(diffInSeconds / 60);
  if (diffInMinutes < 60) {
    return `${diffInMinutes} minute${diffInMinutes > 1 ? "s" : ""} ago`;
  }

  const diffInHours = Math.floor(diffInMinutes / 60);
  if (diffInHours < 24) {
    return `${diffInHours} hour${diffInHours > 1 ? "s" : ""} ago`;
  }

  const diffInDays = Math.floor(diffInHours / 24);
  if (diffInDays < 7) {
    return `${diffInDays} day${diffInDays > 1 ? "s" : ""} ago`;
  }

  // For older dates, show the actual date
  return date.toLocaleDateString();
}

export function generateId(): string {
  return Math.random().toString(36).substr(2, 9);
}

export function debounce<T extends (...args: any[]) => any>(
  func: T,
  delay: number
): (...args: Parameters<T>) => void {
  let timeoutId: NodeJS.Timeout;
  return (...args: Parameters<T>) => {
    clearTimeout(timeoutId);
    timeoutId = setTimeout(() => func(...args), delay);
  };
}

/**
 * Limit JSON object depth for preview performance
 * @param obj - Object to limit depth
 * @param maxDepth - Maximum depth to traverse (default: 1)
 * @returns Depth-limited object
 */
export function limitJsonDepth(obj: any, maxDepth: number = 1): any {
  if (maxDepth <= 0) {
    if (typeof obj === 'object' && obj !== null) {
      if (Array.isArray(obj)) {
        return `[Array(${obj.length})]`;
      }
      return `{Object with ${Object.keys(obj).length} keys}`;
    }
    return obj;
  }

  if (typeof obj !== 'object' || obj === null) {
    return obj;
  }

  if (Array.isArray(obj)) {
    return obj.slice(0, 3).map(item => limitJsonDepth(item, maxDepth - 1))
      .concat(obj.length > 3 ? [`... ${obj.length - 3} more items`] : []);
  }

  const limited: any = {};
  const keys = Object.keys(obj);
  const maxKeys = 5;
  
  for (let i = 0; i < Math.min(keys.length, maxKeys); i++) {
    const key = keys[i];
    if (key !== undefined) {
      limited[key] = limitJsonDepth(obj[key], maxDepth - 1);
    }
  }
  
  if (keys.length > maxKeys) {
    limited[`_truncated_${keys.length - maxKeys}_more_keys`] = '...';
  }

  return limited;
}