# .env (NEVER commit)
GRAMMARLY_CLIENT_ID=your_client_id
GRAMMARLY_CLIENT_SECRET=your_client_secret
GRAMMARLY_ACCESS_TOKEN=  # Populated after OAuth

// auth.ts
import 'dotenv/config';

async function getAccessToken(): Promise<string> {
  const response = await fetch('https://api.grammarly.com/ecosystem/api/v1/oauth/token', {
    method: 'POST',
    headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
    body: new URLSearchParams({
      grant_type: 'client_credentials',
      client_id: process.env.GRAMMARLY_CLIENT_ID!,
      client_secret: process.env.GRAMMARLY_CLIENT_SECRET!,
    }),
  });
  const { access_token, expires_in } = await response.json();
  console.log(`Token obtained, expires in ${expires_in}s`);
  return access_token;
}

async function verify(token: string) {
  const response = await fetch('https://api.grammarly.com/ecosystem/api/v2/scores', {
    method: 'POST',
    headers: { 'Authorization': `Bearer ${token}`, 'Content-Type': 'application/json' },
    body: JSON.stringify({ text: 'This is a test sentence for verification.' }),
  });
  if (response.ok) console.log('Grammarly API connection verified');
  else console.error('Verification failed:', response.status);
}