/**
 * CAPTCHA auto-solving via 2captcha or CapSolver APIs.
 * Supports reCAPTCHA v2, hCaptcha, and Cloudflare Turnstile.
 */

export type CaptchaSolverProvider = '2captcha' | 'capsolver';

interface SolveResult {
  token: string;
  provider: CaptchaSolverProvider;
}

// Poll interval and max attempts
const POLL_INTERVAL_MS = 3_000;
const MAX_ATTEMPTS = 40; // 2 min max

/**
 * Detect CAPTCHA type and sitekey on the page, then solve it.
 * Returns null if no CAPTCHA found or solver not configured.
 * Throws on solve failure.
 */
export async function solveCaptcha(
  page: any,
  pageUrl: string,
  apiKey: string,
  provider: CaptchaSolverProvider = '2captcha'
): Promise<SolveResult | null> {
  // Detect CAPTCHA type
  const captchaInfo = await page.evaluate(() => {
    // reCAPTCHA v2
    const recaptchaEl = document.querySelector('.g-recaptcha, [data-sitekey]') as HTMLElement | null;
    if (recaptchaEl) {
      const sitekey = recaptchaEl.getAttribute('data-sitekey') || '';
      return { type: 'recaptcha', sitekey };
    }
    // hCaptcha
    const hcaptchaEl = document.querySelector('.h-captcha, [data-hcaptcha-sitekey]') as HTMLElement | null;
    if (hcaptchaEl) {
      const sitekey = hcaptchaEl.getAttribute('data-sitekey') || hcaptchaEl.getAttribute('data-hcaptcha-sitekey') || '';
      return { type: 'hcaptcha', sitekey };
    }
    // Cloudflare Turnstile
    const turnstileEl = document.querySelector('.cf-turnstile') as HTMLElement | null;
    if (turnstileEl) {
      const sitekey = turnstileEl.getAttribute('data-sitekey') || '';
      return { type: 'turnstile', sitekey };
    }
    return null;
  });

  if (!captchaInfo?.sitekey) return null;

  const token = provider === 'capsolver'
    ? await solveWithCapSolver(captchaInfo.type, captchaInfo.sitekey, pageUrl, apiKey)
    : await solveWith2Captcha(captchaInfo.type, captchaInfo.sitekey, pageUrl, apiKey);

  // Inject the token into the page
  await page.evaluate((t: string, type: string) => {
    // reCAPTCHA
    if (type === 'recaptcha') {
      const el = document.querySelector('textarea.g-recaptcha-response') as HTMLTextAreaElement | null;
      if (el) { el.value = t; }
      // Also trigger the callback if registered
      if ((window as any).grecaptcha?.getResponse && document.querySelector('[data-callback]')) {
        const cb = (document.querySelector('[data-callback]') as HTMLElement)?.getAttribute('data-callback');
        if (cb && (window as any)[cb]) (window as any)[cb](t);
      }
    }
    // hCaptcha
    if (type === 'hcaptcha') {
      const el = document.querySelector('textarea[name="h-captcha-response"]') as HTMLTextAreaElement | null;
      if (el) { el.value = t; }
    }
    // Turnstile
    if (type === 'turnstile') {
      const el = document.querySelector('[name="cf-turnstile-response"]') as HTMLInputElement | null;
      if (el) { el.value = t; }
    }
  }, token, captchaInfo.type);

  return { token, provider };
}

async function solveWith2Captcha(type: string, sitekey: string, pageUrl: string, apiKey: string): Promise<string> {
  const method = type === 'hcaptcha' ? 'hcaptcha' : type === 'turnstile' ? 'turnstile' : 'userrecaptcha';

  const submitRes = await fetch('http://2captcha.com/in.php', {
    method: 'POST',
    body: new URLSearchParams({
      key: apiKey,
      method,
      googlekey: sitekey,
      pageurl: pageUrl,
      json: '1',
    }),
  });
  const submitData = await submitRes.json() as { status: number; request: string };
  if (submitData.status !== 1) throw new Error(`2captcha submit failed: ${submitData.request}`);
  const taskId = submitData.request;

  // Poll for result
  for (let i = 0; i < MAX_ATTEMPTS; i++) {
    await new Promise(r => setTimeout(r, POLL_INTERVAL_MS));
    const pollRes = await fetch(`http://2captcha.com/res.php?key=${apiKey}&action=get&id=${taskId}&json=1`);
    const pollData = await pollRes.json() as { status: number; request: string };
    if (pollData.status === 1) return pollData.request;
    if (pollData.request !== 'CAPCHA_NOT_READY') throw new Error(`2captcha error: ${pollData.request}`);
  }
  throw new Error('2captcha timed out after 2 minutes');
}

async function solveWithCapSolver(type: string, sitekey: string, pageUrl: string, apiKey: string): Promise<string> {
  const taskType = type === 'hcaptcha' ? 'HCaptchaTaskProxyless'
    : type === 'turnstile' ? 'AntiTurnstileTaskProxyless'
    : 'ReCaptchaV2TaskProxyless';

  const createRes = await fetch('https://api.capsolver.com/createTask', {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify({
      clientKey: apiKey,
      task: { type: taskType, websiteURL: pageUrl, websiteKey: sitekey },
    }),
  });
  const createData = await createRes.json() as { errorId: number; taskId?: string; errorDescription?: string };
  if (createData.errorId !== 0) throw new Error(`CapSolver create failed: ${createData.errorDescription}`);
  const taskId = createData.taskId!;

  for (let i = 0; i < MAX_ATTEMPTS; i++) {
    await new Promise(r => setTimeout(r, POLL_INTERVAL_MS));
    const pollRes = await fetch('https://api.capsolver.com/getTaskResult', {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ clientKey: apiKey, taskId }),
    });
    const pollData = await pollRes.json() as { errorId: number; status: string; solution?: { gRecaptchaResponse?: string; token?: string }; errorDescription?: string };
    if (pollData.errorId !== 0) throw new Error(`CapSolver error: ${pollData.errorDescription}`);
    if (pollData.status === 'ready') {
      return pollData.solution?.gRecaptchaResponse ?? pollData.solution?.token ?? '';
    }
  }
  throw new Error('CapSolver timed out after 2 minutes');
}