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

/**
 * Utility function to merge Tailwind CSS classes with clsx support
 * Handles class merging, conflict resolution, and conditional classes
 */
export function cn(...inputs: ClassValue[]) {
  return twMerge(clsx(inputs));
}

/**
 * Utility function to check if a value is not null or undefined
 */
export function isNonNullable<T>(value: T | null | undefined): value is T {
  return value != null;
}

/**
 * Utility function to format currency
 */
export function formatCurrency(amount: number, currency: string = 'EUR', locale: string = 'de-DE'): string {
  return new Intl.NumberFormat(locale, {
    style: 'currency',
    currency: currency,
    minimumFractionDigits: 2,
    maximumFractionDigits: 2,
  }).format(amount);
}

/**
 * Utility function to format date
 */
export function formatDate(date: Date | string, locale: string = 'de-DE'): string {
  const d = typeof date === 'string' ? new Date(date) : date;
  return new Intl.DateTimeFormat(locale, {
    year: 'numeric',
    month: 'long',
    day: 'numeric',
  }).format(d);
}

/**
 * Utility function to generate slug from text
 */
export function generateSlug(text: string): string {
  return text
    .toLowerCase()
    .replace(/[^\w\s-]/g, '')
    .replace(/\s+/g, '-')
    .replace(/-+/g, '-')
    .trim();
}

/**
 * Utility function to debounce function calls
 */
export function debounce<T extends (...args: any[]) => any>(
  func: T,
  wait: number
): (...args: Parameters<T>) => void {
  let timeout: NodeJS.Timeout;
  return (...args: Parameters<T>) => {
    clearTimeout(timeout);
    timeout = setTimeout(() => func(...args), wait);
  };
}

/**
 * Utility function to get initials from a name
 */
export function getInitials(name: string): string {
  return name
    .split(' ')
    .map(part => part[0])
    .join('')
    .toUpperCase()
    .slice(0, 2);
}

/**
 * Utility function to truncate text
 */
export function truncate(text: string, maxLength: number, suffix = '...'): string {
  if (text.length <= maxLength) return text;
  return text.slice(0, maxLength - suffix.length) + suffix;
}