bambuddy/frontend/src/hooks/useIsMobile.ts

import { useState, useEffect } from 'react';

const MOBILE_BREAKPOINT = 768;

export function useIsMobile(): boolean {
  const [isMobile, setIsMobile] = useState(() =>
    typeof window !== 'undefined' ? window.innerWidth < MOBILE_BREAKPOINT : false
  );

  useEffect(() => {
    const mediaQuery = window.matchMedia(`(max-width: ${MOBILE_BREAKPOINT - 1}px)`);

    const handleChange = (e: MediaQueryListEvent) => {
      setIsMobile(e.matches);
    };

    // Set initial value
    setIsMobile(mediaQuery.matches);

    // Modern browsers support addEventListener
    mediaQuery.addEventListener('change', handleChange);
    return () => mediaQuery.removeEventListener('change', handleChange);
  }, []);

  return isMobile;
}