leggen/frontend/src/lib/utils.ts

import { clsx, type ClassValue } from "clsx";

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

export function formatCurrency(
  amount: number,
  currency: string = "EUR",
): string {
  // Validate currency code - must be 3 letters and a valid ISO 4217 code
  const validCurrency =
    currency && /^[A-Z]{3}$/.test(currency) ? currency : "EUR";

  try {
    return new Intl.NumberFormat("en-US", {
      style: "currency",
      currency: validCurrency,
    }).format(amount);
  } catch {
    // Fallback if currency is still invalid
    console.warn(`Invalid currency code: ${currency}, falling back to EUR`);
    return new Intl.NumberFormat("en-US", {
      style: "currency",
      currency: "EUR",
    }).format(amount);
  }
}

export function formatDate(date: string): string {
  if (!date) return "No date";

  const parsedDate = new Date(date);
  if (isNaN(parsedDate.getTime())) {
    console.warn("Invalid date string:", date);
    return "Invalid date";
  }

  return new Intl.DateTimeFormat("en-US", {
    year: "numeric",
    month: "short",
    day: "numeric",
  }).format(parsedDate);
}

export function formatDateTime(date: string): string {
  if (!date) return "No date";

  const parsedDate = new Date(date);
  if (isNaN(parsedDate.getTime())) {
    console.warn("Invalid date string:", date);
    return "Invalid date";
  }

  return new Intl.DateTimeFormat("en-US", {
    year: "numeric",
    month: "short",
    day: "numeric",
    hour: "2-digit",
    minute: "2-digit",
  }).format(parsedDate);
}