lr-openwrt-tool/src/components/ui/Select.tsx

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

type SelectOption<T extends string> = {
  value: T;
  label: string;
};

type SelectProps<T extends string> = {
  value: T;
  options: SelectOption<T>[];
  onChange: (value: T) => void;
};

export function Select<T extends string>({
  value,
  options,
  onChange,
}: SelectProps<T>) {
  const [open, setOpen] = useState(false);
  const ref = useRef<HTMLDivElement | null>(null);

  const selected =
    options.find((option) => option.value === value) ??
    options[0];

  useEffect(() => {
    function handleClick(event: MouseEvent) {
      if (
        ref.current &&
        !ref.current.contains(event.target as Node)
      ) {
        setOpen(false);
      }
    }

    window.addEventListener('mousedown', handleClick);

    return () => {
      window.removeEventListener('mousedown', handleClick);
    };
  }, []);

  return (
    <div ref={ref} className="relative">
      <button
        type="button"
        onClick={() => setOpen((current) => !current)}
        className="flex w-full items-center justify-between rounded-xl border border-white/10 bg-slate-950 px-3 py-3 text-left text-sm text-slate-200 outline-none transition hover:border-blue-500/30 focus:border-blue-500/40"
      >
        <span>{selected.label}</span>
        <span className="text-xs text-slate-500">▼</span>
      </button>

      {open && (
        <div className="absolute z-50 mt-2 w-full overflow-hidden rounded-xl border border-white/10 bg-slate-950 shadow-2xl">
          {options.map((option) => {
            const active = option.value === value;

            return (
              <button
                key={option.value}
                type="button"
                onClick={() => {
                  onChange(option.value);
                  setOpen(false);
                }}
                className={`block w-full px-3 py-2 text-left text-sm transition ${
                  active
                    ? 'bg-blue-500/15 text-blue-200'
                    : 'text-slate-300 hover:bg-white/5 hover:text-white'
                }`}
              >
                {option.label}
              </button>
            );
          })}
        </div>
      )}
    </div>
  );
}