utils.ts

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

/**
 * Merge Tailwind CSS classes with clsx
 */
export function cn(...inputs: ClassValue[]) {
  return twMerge(clsx(inputs));
}

/**
 * Format duration in seconds to a human-readable string
 * e.g., 323 -> "5m 23s"
 */
export function formatDuration(seconds: number): string {
  if (seconds < 60) {
    return `${seconds}s`;
  }

  const minutes = Math.floor(seconds / 60);
  const remainingSeconds = seconds % 60;

  if (minutes < 60) {
    return remainingSeconds > 0 ? `${minutes}m ${remainingSeconds}s` : `${minutes}m`;
  }

  const hours = Math.floor(minutes / 60);
  const remainingMinutes = minutes % 60;

  if (remainingMinutes > 0) {
    return `${hours}h ${remainingMinutes}m`;
  }

  return `${hours}h`;
}

/**
 * Format a date to relative time (Today, Yesterday, or date string)
 */
export function formatRelativeDate(date: Date): string {
  const now = new Date();
  const today = new Date(now.getFullYear(), now.getMonth(), now.getDate());
  const yesterday = new Date(today);
  yesterday.setDate(yesterday.getDate() - 1);

  const inputDate = new Date(date.getFullYear(), date.getMonth(), date.getDate());

  if (inputDate.getTime() === today.getTime()) {
    return 'Today';
  }

  if (inputDate.getTime() === yesterday.getTime()) {
    return 'Yesterday';
  }

  // Format as "Mon, Jan 15"
  return date.toLocaleDateString('en-US', {
    weekday: 'short',
    month: 'short',
    day: 'numeric',
  });
}

/**
 * Format time to 12-hour format (e.g., "2:30 PM")
 */
export function formatTime(date: Date): string {
  return date.toLocaleTimeString('en-US', {
    hour: 'numeric',
    minute: '2-digit',
    hour12: true,
  });
}

/**
 * Format notification timestamp with time (e.g., "2:30 PM" for today, "Yesterday 2:30 PM", or "Jan 15, 2:30 PM")
 */
export function formatNotificationTimestamp(date: Date): string {
  const now = new Date();
  const today = new Date(now.getFullYear(), now.getMonth(), now.getDate());
  const yesterday = new Date(today);
  yesterday.setDate(yesterday.getDate() - 1);

  const inputDate = new Date(date.getFullYear(), date.getMonth(), date.getDate());
  const timeStr = date.toLocaleTimeString('en-US', {
    hour: 'numeric',
    minute: '2-digit',
    hour12: true,
  });

  if (inputDate.getTime() === today.getTime()) {
    return timeStr;
  }

  if (inputDate.getTime() === yesterday.getTime()) {
    return `Yesterday ${timeStr}`;
  }

  // Format as "Jan 15, 2:30 PM"
  const dateStr = date.toLocaleDateString('en-US', {
    month: 'short',
    day: 'numeric',
  });
  return `${dateStr}, ${timeStr}`;
}

/**
 * Group items by a key function
 */
export function groupBy<T, K extends string>(
  items: T[],
  getKey: (item: T) => K
): Record<K, T[]> {
  return items.reduce(
    (result, item) => {
      const key = getKey(item);
      if (!result[key]) {
        result[key] = [];
      }
      result[key].push(item);
      return result;
    },
    {} as Record<K, T[]>
  );
}