Error handling

class Fido2WebSdkError extends Error {
  name: 'Fido2WebSdkError'; // Error type identifier
  code: string;             // Unique error code (e.g. 'DBK-0005')
  category: string;         // Error category: 'DBK', 'VAL', 'CONV', or 'WEB'
  shortDesc: string;        // Brief description of the error type
  details: string;          // Detailed error message with context
  message: string;          // Full formatted message: '[CODE]: details'
}

{
  name: 'Fido2WebSdkError',
  code: 'DBK-0010',
  category: 'DBK',
  shortDesc: 'Failed to open IndexedDB',
  details: 'IndexedDB is not available or blocked by browser settings',
  message: '[DBK-0010]: IndexedDB is not available or blocked by browser settings'
}

if (error.name === 'Fido2WebSdkError') {
  // Handle SDK-specific error
  console.error(`SDK error [${error.code}]:`, error.details);
} else {
  // Handle browser error (e.g. NotAllowedError, NotFoundError)
  console.error('Browser error:', error.name, error.message);
}

async function registerUser(attestationOptions) {
  try {
    const credential = await webauthnCreateCred({ options: attestationOptions });
    return { success: true, credential };

  } catch (error) {
    if (error.name === 'Fido2WebSdkError') {
      switch (error.category) {
        case 'DBK':
          return { success: false, errorType: 'device-key', message: error.shortDesc, code: error.code };
        case 'WEB':
          return { success: false, errorType: 'webauthn', message: error.shortDesc, code: error.code };
        case 'VAL':
          return { success: false, errorType: 'validation', message: error.shortDesc, code: error.code };
        case 'CONV':
          return { success: false, errorType: 'conversion', message: error.shortDesc, code: error.code };
        default:
          return { success: false, errorType: 'sdk', message: error.details, code: error.code };
      }
    } else {
      // Browser-native errors
      if (error.name === 'NotAllowedError') {
        return { success: false, errorType: 'cancelled', message: 'Operation cancelled or timed out' };
      }
      if (error.name === 'InvalidStateError') {
        return { success: false, errorType: 'already-registered', message: 'This authenticator is already registered' };
      }
      return { success: false, errorType: 'browser', message: error.message };
    }
  }
}

function getUserFriendlyMessage(error) {
  if (error.name === 'Fido2WebSdkError') {
    switch (error.code) {
      case 'DBK-0010':
        return 'Browser storage is unavailable. Please check your browser settings.';
      case 'DBK-0012':
        return 'Authentication system not initialized. Please reload the page.';
      case 'DBK-0015':
        return 'No authentication key found for this device. Please register first.';
      default:
        return `Authentication error: ${error.shortDesc}`;
    }
  }

  switch (error.name) {
    case 'NotAllowedError':
      return 'Operation was cancelled or timed out. Please try again.';
    case 'NotSupportedError':
      return 'Your browser does not support passwordless authentication.';
    case 'SecurityError':
      return 'Security requirements not met. Please use HTTPS.';
    case 'InvalidStateError':
      return 'This authenticator is already registered.';
    case 'NotFoundError':
      return 'No matching credentials found. Please register first.';
    default:
      return 'An unexpected error occurred. Please try again.';
  }
}

window.addEventListener('load', async () => {
  await initSdk();
});

try {
  await initSdk();
} catch (error) {
  if (error.code === 'DBK-0010') {
    showMessage('Browser storage is required. Please enable it in your browser settings.');
    disableFido2Features();
  }
}

try {
  const credential = await webauthnCreateCred({ options });
} catch (error) {
  if (error.name === 'NotAllowedError') {
    showMessage('Operation cancelled. Please try again when ready.');
    enableRetryButton();
  }
}

try {
  const credential = await webauthnCreateCred({ options });
} catch (error) {
  if (error.name === 'InvalidStateError') {
    showMessage('This security key is already registered. Use it to sign in.');
    showLoginButton();
  }
}

try {
  const credential = await webauthnGetCred({ options });
} catch (error) {
  if (error.name === 'NotFoundError') {
    showMessage('No credentials found. Would you like to register?');
    showRegistrationButton();
  }
}

try {
  const credential = await webauthnGetCred({ options });
} catch (error) {
  if (error.code === 'DBK-0015') {
    showMessage('No authentication key found for this device. Please register on this browser first.');
    redirectToRegistration();
  }
}

const result = await registerDeviceBoundCredential({
  assertionReq,
  attestationReq,
  onFallbackConfirmation: () => new Promise((resolve) => {
    showMyModal({
      message: 'Your passkey was not found on this browser. Register a new one?',
      onConfirm: () => resolve(true),
      onCancel:  () => resolve(false),
    });
  }),
});

function logError(error, context) {
  const log = {
    timestamp: new Date().toISOString(),
    context,
    errorName: error.name,
    errorMessage: error.message,
    userAgent: navigator.userAgent,
    url: window.location.href
  };

  if (error.name === 'Fido2WebSdkError') {
    log.sdkError = {
      code: error.code,
      category: error.category,
      shortDesc: error.shortDesc,
      details: error.details
    };
  }

  console.error('Error log:', log);
}