'use client';

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

declare global {
  interface Window {
    turnstile?: {
      render: (
        container: string | HTMLElement,
        options: {
          sitekey: string;
          callback: (token: string) => void;
          'expired-callback'?: () => void;
          'error-callback'?: () => void;
          theme?: 'auto' | 'light' | 'dark';
        },
      ) => string;
      remove: (widgetId: string) => void;
      reset: (widgetId?: string) => void;
    };
  }
}

const TURNSTILE_SCRIPT_ID = 'cloudflare-turnstile-script';
const TURNSTILE_SCRIPT_SRC = 'https://challenges.cloudflare.com/turnstile/v0/api.js?render=explicit';

interface TurnstileWidgetProps {
  siteKey: string;
  onVerify: (token: string) => void;
  onExpire?: () => void;
  onError?: () => void;
}

export function TurnstileWidget({
  siteKey,
  onVerify,
  onExpire,
  onError,
}: TurnstileWidgetProps) {
  const containerRef = useRef<HTMLDivElement | null>(null);
  const widgetIdRef = useRef<string | null>(null);
  const elementId = useId().replace(/:/g, '-');

  useEffect(() => {
    let cancelled = false;

    const mountWidget = () => {
      if (cancelled || !containerRef.current || !window.turnstile) {
        return;
      }

      if (widgetIdRef.current) {
        window.turnstile.remove(widgetIdRef.current);
        widgetIdRef.current = null;
      }

      widgetIdRef.current = window.turnstile.render(containerRef.current, {
        sitekey: siteKey,
        callback: onVerify,
        'expired-callback': onExpire,
        'error-callback': onError,
        theme: 'auto',
      });
    };

    const existingScript = document.getElementById(TURNSTILE_SCRIPT_ID) as HTMLScriptElement | null;

    if (window.turnstile) {
      mountWidget();
    } else if (existingScript) {
      existingScript.addEventListener('load', mountWidget);
    } else {
      const script = document.createElement('script');
      script.id = TURNSTILE_SCRIPT_ID;
      script.src = TURNSTILE_SCRIPT_SRC;
      script.async = true;
      script.defer = true;
      script.addEventListener('load', mountWidget);
      document.head.appendChild(script);
    }

    return () => {
      cancelled = true;
      const script = document.getElementById(TURNSTILE_SCRIPT_ID) as HTMLScriptElement | null;
      if (script) {
        script.removeEventListener('load', mountWidget);
      }
      if (widgetIdRef.current && window.turnstile) {
        window.turnstile.remove(widgetIdRef.current);
        widgetIdRef.current = null;
      }
    };
  }, [onError, onExpire, onVerify, siteKey]);

  return <div id={elementId} ref={containerRef} className='min-h-16' />;
}