# Basic message sending request
curl -X POST "https://api.telegram.org/bot123456789:ABCdefGHIjklMNOpqrsTUVwxyz/sendMessage" \
  -H "Content-Type: application/json" \
  -d '{
    "chat_id": "987654321",
    "text": "Hello from my bot!"
  }'

# Response
{
  "ok": true,
  "result": {
    "message_id": 42,
    "date": 1693526400,
    "text": "Hello from my bot!"
  }
}

// JavaScript example using fetch
const BOT_TOKEN = 'YOUR_BOT_TOKEN_HERE';
const CHAT_ID = 'YOUR_CHAT_ID';

async function sendMessage(message) {
  const url = `https://api.telegram.org/bot${BOT_TOKEN}/sendMessage`;
  
  const response = await fetch(url, {
    method: 'POST',
    headers: {
      'Content-Type': 'application/json',
    },
    body: JSON.stringify({
      chat_id: CHAT_ID,
      text: message,
      parse_mode: 'HTML'
    })
  });
  
  const result = await response.json();
  
  if (result.ok) {
    console.log('Message sent successfully!');
    return result.result;
  } else {
    console.error('Error:', result.description);
    throw new Error(result.description);
  }
}

// Usage
sendMessage('Hello from my Telegram bot!');

// ✅ CORRECT - Using environment variables
// .env file (add to .gitignore!)
TELEGRAM_BOT_TOKEN=123456789:ABCdefGHIjklMNOpqrsTUVwxyz
CHAT_ID=987654321

// JavaScript code
const BOT_TOKEN = process.env.TELEGRAM_BOT_TOKEN;
const CHAT_ID = process.env.CHAT_ID;

if (!BOT_TOKEN) {
  throw new Error('TELEGRAM_BOT_TOKEN environment variable is required');
}

// ❌ WRONG - Hardcoded in source code
const BOT_TOKEN = '123456789:ABCdefGHIjklMNOpqrsTUVwxyz'; // NEVER DO THIS!

// Implementing exponential backoff for rate limits
async function sendMessageWithRetry(message, maxRetries = 3) {
  for (let attempt = 1; attempt <= maxRetries; attempt++) {
    try {
      const response = await sendTelegramMessage(message);
      return response; // Success!
      
    } catch (error) {
      if (error.error_code === 429) { // Too Many Requests
        const retryAfter = error.parameters?.retry_after || Math.pow(2, attempt);
        console.log(`Rate limited. Waiting ${retryAfter} seconds...`);
        
        await new Promise(resolve => setTimeout(resolve, retryAfter * 1000));
        continue; // Retry
      }
      throw error; // Other errors, don't retry
    }
  }
  throw new Error('Max retries exceeded');
}