// content/duck-mail.js — Content script for DuckDuckGo Email Protection autofill settings

console.log('[MultiPage:duck-mail] Content script loaded on', location.href);

chrome.runtime.onMessage.addListener((message, sender, sendResponse) => {
  if (message.type === 'FETCH_DUCK_EMAIL') {
    resetStopState();
    fetchDuckEmail(message.payload).then(result => {
      sendResponse(result);
    }).catch(err => {
      if (isStopError(err)) {
        log('Duck Mail: Stopped by user.', 'warn');
        sendResponse({ stopped: true, error: err.message });
        return;
      }
      sendResponse({ error: err.message });
    });
    return true;
  }

  if (message.type === 'EXTRACT_DUCK_TOKEN') {
    extractDuckToken().then(result => {
      sendResponse(result);
    }).catch(err => {
      sendResponse({ error: err.message });
    });
    return true;
  }
});

async function extractDuckToken() {
  log('Duck Mail: Extracting access token...');

  // The DuckDuckGo email app stores userData in a React state.
  // We can intercept it by reading the __NEXT_DATA__ or by calling their API
  // with cookies that the browser already has.
  // Strategy: call the dashboard API endpoint which returns user info including token.

  // Strategy 1: Try to find token in page's fetch calls by hooking into the app state
  // The app calls quack.duckduckgo.com/api/email/dashboard with credentials
  try {
    const resp = await fetch('https://quack.duckduckgo.com/api/email/dashboard', {
      credentials: 'include',
    });
    if (resp.ok) {
      const data = await resp.json();
      // Response has { user: { access_token, username, ... } }
      const token = data?.user?.access_token;
      const username = data?.user?.username;
      if (token) {
        log(`Duck Mail: Token extracted for ${username}`, 'ok');
        return { token, username };
      }
    }
  } catch (e) {
    log(`Duck Mail: Dashboard API failed: ${e.message}`, 'warn');
  }

  throw new Error('Could not extract DuckDuckGo access token. Make sure you are logged in.');
}

async function fetchDuckEmail(payload = {}) {
  const { generateNew = true } = payload;

  log(`Duck Mail: ${generateNew ? 'Generating' : 'Reading'} private address...`);

  await waitForElement(
    'input.AutofillSettingsPanel__PrivateDuckAddressValue, button.AutofillSettingsPanel__GeneratorButton',
    15000
  );

  const getAddressInput = () => document.querySelector('input.AutofillSettingsPanel__PrivateDuckAddressValue');
  const getGeneratorButton = () => document.querySelector('button.AutofillSettingsPanel__GeneratorButton')
    || Array.from(document.querySelectorAll('button')).find(btn => /generate private duck address/i.test(btn.textContent || ''));
  const readEmail = () => {
    const value = getAddressInput()?.value?.trim() || '';
    return value.includes('@duck.com') ? value : '';
  };

  const waitForEmailValue = async (previousValue = '') => {
    for (let i = 0; i < 100; i++) {
      const nextValue = readEmail();
      if (nextValue && nextValue !== previousValue) {
        return nextValue;
      }
      await sleep(150);
    }
    throw new Error('Timed out waiting for Duck address to appear.');
  };

  const currentEmail = readEmail();
  if (currentEmail && !generateNew) {
    log(`Duck Mail: Found existing address ${currentEmail}`);
    return { email: currentEmail, generated: false };
  }

  await humanPause(500, 1300);
  const generatorButton = getGeneratorButton();
  if (!generatorButton) {
    if (currentEmail) {
      log(`Duck Mail: Reusing existing address ${currentEmail}`, 'warn');
      return { email: currentEmail, generated: false };
    }
    throw new Error('Could not find "Generate Private Duck Address" button.');
  }

  generatorButton.click();
  log('Duck Mail: Clicked "Generate Private Duck Address"');

  const nextEmail = await waitForEmailValue(currentEmail);
  log(`Duck Mail: Ready address ${nextEmail}`, 'ok');
  return { email: nextEmail, generated: true };
}