import React, { useEffect, useRef, useState } from 'react';
import ReCAPTCHA from 'react-google-recaptcha';
import { recaptchaService } from '../../features/system/services/systemSettingsService';

interface RecaptchaProps {
  onChange?: (token: string | null) => void;
  onError?: (error: string) => void;
  theme?: 'light' | 'dark';
  size?: 'normal' | 'compact';
  className?: string;
}

// Cache for reCAPTCHA settings to avoid multiple API calls
interface RecaptchaSettingsCache {
  siteKey: string;
  enabled: boolean;
  timestamp: number;
}

const CACHE_KEY = 'recaptcha_settings_cache';
const CACHE_DURATION = 5 * 60 * 1000; // 5 minutes

let settingsCache: RecaptchaSettingsCache | null = null;
let fetchPromise: Promise<RecaptchaSettingsCache | null> | null = null;

const getCachedSettings = (): RecaptchaSettingsCache | null => {
  // Check in-memory cache first
  if (settingsCache) {
    const age = Date.now() - settingsCache.timestamp;
    if (age < CACHE_DURATION) {
      return settingsCache;
    }
  }

  // Check localStorage cache
  try {
    const cached = localStorage.getItem(CACHE_KEY);
    if (cached) {
      const parsed: RecaptchaSettingsCache = JSON.parse(cached);
      const age = Date.now() - parsed.timestamp;
      if (age < CACHE_DURATION) {
        settingsCache = parsed;
        return parsed;
      }
    }
  } catch (error) {
    // Ignore cache errors
  }

  return null;
};

const fetchRecaptchaSettings = async (): Promise<RecaptchaSettingsCache | null> => {
  // If there's already a fetch in progress, return that promise
  if (fetchPromise) {
    return fetchPromise;
  }

  fetchPromise = (async () => {
    try {
      const response = await recaptchaService.getRecaptchaSettings();
      if (response.status === 'success' && response.data) {
        const settings: RecaptchaSettingsCache = {
          siteKey: response.data.recaptcha_site_key || '',
          enabled: response.data.recaptcha_enabled || false,
          timestamp: Date.now(),
        };

        // Update caches
        settingsCache = settings;
        try {
          localStorage.setItem(CACHE_KEY, JSON.stringify(settings));
        } catch (error) {
          // Ignore localStorage errors
        }

        return settings;
      }
      return null;
    } catch (error) {
      console.error('Error fetching reCAPTCHA settings:', error);
      return null;
    } finally {
      fetchPromise = null;
    }
  })();

  return fetchPromise;
};

const Recaptcha: React.FC<RecaptchaProps> = ({
  onChange,
  onError,
  theme = 'dark',
  size = 'normal',
  className = '',
}) => {
  const recaptchaRef = useRef<ReCAPTCHA>(null);
  const [siteKey, setSiteKey] = useState<string>('');
  const [enabled, setEnabled] = useState<boolean>(false);
  const [loading, setLoading] = useState<boolean>(true);

  useEffect(() => {
    const loadSettings = async () => {
      // Try to get from cache first
      const cached = getCachedSettings();
      if (cached) {
        setSiteKey(cached.siteKey);
        setEnabled(cached.enabled);
        setLoading(false);
        return;
      }

      // Fetch from API if not cached
      const settings = await fetchRecaptchaSettings();
      if (settings) {
        setSiteKey(settings.siteKey);
        setEnabled(settings.enabled);
      } else {
        if (onError) {
          onError('Failed to load reCAPTCHA settings');
        }
      }
      setLoading(false);
    };

    loadSettings();
  }, [onError]);

  const handleChange = (token: string | null) => {
    if (onChange) {
      onChange(token);
    }
  };

  const handleExpired = () => {
    if (onChange) {
      onChange(null);
    }
  };

  const handleError = () => {
    if (onError) {
      onError('reCAPTCHA error occurred');
    }
    if (onChange) {
      onChange(null);
    }
  };

  if (loading) {
    return null;
  }

  if (!enabled || !siteKey) {
    return null;
  }

  return (
    <div className={className}>
      <ReCAPTCHA
        ref={recaptchaRef}
        sitekey={siteKey}
        onChange={handleChange}
        onExpired={handleExpired}
        onError={handleError}
        theme={theme}
        size={size}
      />
    </div>
  );
};

export default Recaptcha;