"use client";

import { useState, useEffect, useRef } from "react";

export interface AnimatedCounterProps {
  value: number;
  duration?: number;
  prefix?: string;
  suffix?: string;
  formatter?: (value: number) => string;
}

export function AnimatedCounter({
  value,
  duration = 2000,
  prefix = "",
  suffix = "",
  formatter
}: AnimatedCounterProps) {
  const [displayValue, setDisplayValue] = useState(0);
  const startTimeRef = useRef<number | null>(null);
  const frameRef = useRef<number | null>(null);

  // Easing function for smoother animation
  const easeOutQuad = (t: number): number => t * (2 - t);

  useEffect(() => {
    // Reset start time on new value
    startTimeRef.current = null;
    
    // Cancel any ongoing animation
    if (frameRef.current) {
      cancelAnimationFrame(frameRef.current);
    }

    // Animation function
    const animate = (timestamp: number) => {
      if (!startTimeRef.current) {
        startTimeRef.current = timestamp;
      }

      const elapsed = timestamp - startTimeRef.current;
      const progress = Math.min(elapsed / duration, 1);
      const easedProgress = easeOutQuad(progress);
      
      const nextValue = Math.floor(easedProgress * value);
      setDisplayValue(nextValue);

      if (progress < 1) {
        frameRef.current = requestAnimationFrame(animate);
      } else {
        setDisplayValue(value);
      }
    };

    // Start the animation
    frameRef.current = requestAnimationFrame(animate);

    return () => {
      if (frameRef.current) {
        cancelAnimationFrame(frameRef.current);
      }
    };
  }, [value, duration]);

  const formattedValue = formatter 
    ? formatter(displayValue) 
    : `${prefix}${displayValue.toLocaleString()}${suffix}`;

  return <span>{formattedValue}</span>;
}