import { clsx, type ClassValue } from 'clsx';
import { twMerge } from 'tailwind-merge';
import { type Timestamp } from '@/lib/types';

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

export const ccn = ({
  context,
  className,
  on = '',
  off = '',
}: {
  context: boolean;
  className: string;
  on: string;
  off: string;
}) => {
  return twMerge(className, context ? on : off);
};

const toDate = (ts: Timestamp): Date | null => {
  if (ts instanceof Date) return isNaN(ts.getTime()) ? null : ts;

  if (typeof ts === 'number') {
    // Heuristic: treat small numbers as seconds
    const ms = ts < 1_000_000_000_000 ? ts * 1000 : ts;
    const d = new Date(ms);
    return isNaN(d.getTime()) ? null : d;
  }

  // string: try numeric first, then ISO/date string
  const asNum = Number(ts);
  const d =
    Number.isFinite(asNum) && asNum !== 0 ? toDate(asNum) : new Date(ts);

  return d && !isNaN(d.getTime()) ? d : null;
};

export const formatTime = (timestamp: Timestamp, locale = 'en-US'): string => {
  const date = toDate(timestamp);
  if (!date) return '--:--';
  return date.toLocaleTimeString(locale, {
    hour: 'numeric',
    minute: 'numeric',
  });
};

export const formatDate = (timestamp: Timestamp, locale = 'en-US'): string => {
  const date = toDate(timestamp);
  if (!date) return '--/--';
  return date.toLocaleDateString(locale, {
    month: 'long',
    day: 'numeric',
  });
};