import { onMounted, onUnmounted, ref } from 'vue';

/**
 * Composable for real-time timestamp updates
 * Updates every second to show live "time ago" timestamps
 */
export function useRealTimeUpdate() {
  const currentTime = ref(Date.now());
  let intervalId: NodeJS.Timeout | null = null;

  const updateTime = () => {
    currentTime.value = Date.now();
  };

  onMounted(() => {
    // Update every second for real-time display
    intervalId = setInterval(updateTime, 1000);
  });

  onUnmounted(() => {
    if (intervalId) {
      clearInterval(intervalId);
    }
  });

  return {
    currentTime
  };
}

/**
 * Format timestamp to "time ago" string
 * @param timestamp - Unix timestamp in seconds
 * @param currentTime - Current time for real-time updates
 */
export function formatTimeAgo(timestamp: number, currentTime: number): string {
  const now = Math.floor(currentTime / 1000);
  const then = Math.floor(timestamp);
  const diffSeconds = Math.max(0, now - then); // Prevent negative values

  if (diffSeconds < 60) {
    return `${diffSeconds}s ago`;
  }
  
  const diffMinutes = Math.floor(diffSeconds / 60);
  if (diffMinutes < 60) {
    return `${diffMinutes}m ago`;
  }
  
  const diffHours = Math.floor(diffMinutes / 60);
  if (diffHours < 24) {
    return `${diffHours}h ago`;
  }
  
  const diffDays = Math.floor(diffHours / 24);
  return `${diffDays}d ago`;
}