import { EmailSender } from '@prathammahajan/multi-email-sender';

// 🎯 Initialize with your email provider
const sender = new EmailSender({
  email: {
    service: 'gmail',
    auth: {
      user: 'your-email@gmail.com',
      pass: 'your-app-password' // Use app password for Gmail
    }
  }
});

// 📧 Send to multiple recipients instantly
const results = await sender.sendToMultiple(
  ['user1@example.com', 'user2@example.com'],
  {
    subject: '🎉 Welcome to Our Platform!',
    html: '<h1>Hello there!</h1><p>Thanks for joining us!</p>'
  }
);

console.log(`✅ Sent ${results.filter(r => r.success).length} emails successfully!`);

// Automatically retries failed emails with exponential backoff
const sender = new EmailSender({
  options: {
    maxRetries: 5,        // Try up to 5 times
    retryDelay: 1000,     // Start with 1 second delay
    enableLogging: true   // Track every attempt
  }
});

// Automatically adjusts to your provider's limits
const sender = new EmailSender({
  rateLimit: {
    enabled: true,
    maxEmailsPerMinute: 10,  // Gmail-friendly
    maxEmailsPerHour: 100    // Respectful limits
  }
});

// Create personalized emails with ease
const recipients = [
  { email: 'john@example.com', name: 'John', company: 'Tech Corp' },
  { email: 'jane@example.com', name: 'Jane', company: 'Design Studio' }
];

const emailContent = {
  subject: 'Hello {{name}} from {{company}}!',
  html: `
    <h1>Welcome {{name}}!</h1>
    <p>We're excited to have you from <strong>{{company}}</strong> join our community.</p>
    <p>Best regards,<br>The Team</p>
  `,
  template: {
    name: 'welcome',
    variables: { name: '{{name}}', company: '{{company}}' }
  }
};

await sender.sendToMultiple(recipients, emailContent);

// Get comprehensive insights
const stats = sender.getStatistics();
console.log(`
📈 Email Analytics:
✅ Success Rate: ${((stats.totalSent / (stats.totalSent + stats.totalFailed)) * 100).toFixed(1)}%
📧 Total Sent: ${stats.totalSent}
⏱️  Avg Duration: ${Math.round(stats.averageDuration)}ms
🔄 Total Attempts: ${stats.totalAttempts}
`);

// Send personalized order confirmations
const orderEmails = orders.map(order => ({
  email: order.customerEmail,
  name: order.customerName,
  orderId: order.id,
  total: order.total,
  items: order.items
}));

const emailContent = {
  subject: '🎉 Order Confirmation #{{orderId}}',
  html: `
    <h1>Thank you {{name}}!</h1>
    <p>Your order #{{orderId}} has been confirmed.</p>
    <p><strong>Total: ${{total}}</strong></p>
    <p>We'll send you tracking information soon!</p>
  `,
  template: {
    name: 'order-confirmation',
    variables: { name: '{{name}}', orderId: '{{orderId}}', total: '{{total}}' }
  }
};

await sender.sendToMultiple(orderEmails, emailContent);

// Send newsletters with attachments
const newsletterContent = {
  subject: '📰 Weekly Newsletter - {{date}}',
  html: newsletterHTML,
  attachments: [
    { filename: 'newsletter.pdf', path: './newsletters/weekly.pdf' }
  ],
  template: {
    name: 'newsletter',
    variables: { date: new Date().toLocaleDateString() }
  }
};

// Process in batches for large lists
const batchSize = 50;
for (let i = 0; i < subscribers.length; i += batchSize) {
  const batch = subscribers.slice(i, i + batchSize);
  await sender.sendToMultiple(batch, newsletterContent);
  
  // Add delay between batches
  await new Promise(resolve => setTimeout(resolve, 5000));
}

// Send system notifications
const notifications = [
  { email: 'admin@company.com', type: 'system', message: 'Server backup completed' },
  { email: 'user@example.com', type: 'account', message: 'Password changed successfully' }
];

for (const notification of notifications) {
  const emailContent = {
    subject: `🔔 ${notification.type.charAt(0).toUpperCase() + notification.type.slice(1)} Notification`,
    text: notification.message,
    priority: 'high'
  };
  
  await sender.sendSingle(notification.email, emailContent);
}

// Automatic error categorization and handling
const results = await sender.sendToMultiple(recipients, emailContent);

results.forEach(result => {
  if (!result.success) {
    switch (result.error) {
      case 'authentication':
        console.log('🔐 Auth issue - check credentials');
        break;
      case 'rate_limit':
        console.log('⏱️ Rate limited - will retry automatically');
        break;
      case 'network':
        console.log('🌐 Network issue - retrying with backoff');
        break;
      default:
        console.log('❌ Other error:', result.error);
    }
  }
});

// Get detailed performance insights
const stats = sender.getStatistics();
const logs = sender.getLogs();

console.log(`
📊 Performance Report:
┌─────────────────────────────────────┐
│ 📧 Emails Sent: ${stats.totalSent.toString().padEnd(20)} │
│ ❌ Failed: ${stats.totalFailed.toString().padEnd(23)} │
│ ⏱️  Avg Time: ${Math.round(stats.averageDuration).toString().padEnd(18)}ms │
│ 🔄 Total Attempts: ${stats.totalAttempts.toString().padEnd(15)} │
└─────────────────────────────────────┘

📈 Success Rate: ${((stats.totalSent / (stats.totalSent + stats.totalFailed)) * 100).toFixed(1)}%
🎯 Error Breakdown:`, stats.errorBreakdown);

// Process large lists with progress tracking
const processLargeList = async (recipients, emailContent) => {
  const batchSize = 100;
  const totalBatches = Math.ceil(recipients.length / batchSize);
  
  for (let i = 0; i < recipients.length; i += batchSize) {
    const batchNumber = Math.floor(i / batchSize) + 1;
    const batch = recipients.slice(i, i + batchSize);
    
    console.log(`📦 Processing batch ${batchNumber}/${totalBatches} (${batch.length} recipients)...`);
    
    const results = await sender.sendToMultiple(batch, emailContent);
    const successful = results.filter(r => r.success).length;
    
    console.log(`✅ Batch ${batchNumber} completed: ${successful}/${batch.length} successful`);
    
    // Show progress bar
    const progress = Math.round((batchNumber / totalBatches) * 100);
    console.log(`📊 Progress: [${'█'.repeat(progress/5)}${'░'.repeat(20-progress/5)}] ${progress}%`);
    
    // Rate limiting delay
    if (batchNumber < totalBatches) {
      await new Promise(resolve => setTimeout(resolve, 2000));
    }
  }
};

// Use environment variables
import { createConfigFromEnv } from '@prathammahajan/multi-email-sender';

const config = createConfigFromEnv();
const sender = new EmailSender(config);