#!/usr/bin/env node
import { StdioServerTransport } from '@modelcontextprotocol/sdk/server/stdio.js';
import { TwilioMCPServer } from './server.js';

// Validate environment
const TWILIO_ACCOUNT_SID = process.env.TWILIO_ACCOUNT_SID;
const TWILIO_AUTH_TOKEN = process.env.TWILIO_AUTH_TOKEN;

if (!TWILIO_ACCOUNT_SID) {
  console.error('❌ ERROR: TWILIO_ACCOUNT_SID environment variable is required');
  console.error('');
  console.error('Get your Account SID from:');
  console.error('  1. Log in to Twilio Console: https://console.twilio.com/');
  console.error('  2. Your Account SID is displayed on the dashboard');
  console.error('  3. Set: export TWILIO_ACCOUNT_SID=your_account_sid_here');
  console.error('');
  process.exit(1);
}

if (!TWILIO_AUTH_TOKEN) {
  console.error('❌ ERROR: TWILIO_AUTH_TOKEN environment variable is required');
  console.error('');
  console.error('Get your Auth Token from:');
  console.error('  1. Log in to Twilio Console: https://console.twilio.com/');
  console.error('  2. Click "Show" next to Auth Token on the dashboard');
  console.error('  3. Set: export TWILIO_AUTH_TOKEN=your_auth_token_here');
  console.error('');
  console.error('⚠️  WARNING: Keep your Auth Token secret! It provides full account access.');
  process.exit(1);
}

// Create server instance
const server = new TwilioMCPServer({
  accountSid: TWILIO_ACCOUNT_SID,
  authToken: TWILIO_AUTH_TOKEN,
});

// Graceful shutdown
let isShuttingDown = false;

const shutdown = async (signal: string) => {
  if (isShuttingDown) return;
  isShuttingDown = true;
  
  console.error(`\n📡 Received ${signal}, shutting down Twilio MCP server...`);
  
  try {
    await server.close();
    console.error('✅ Server closed gracefully');
    process.exit(0);
  } catch (error) {
    console.error('❌ Error during shutdown:', error);
    process.exit(1);
  }
};

process.on('SIGINT', () => shutdown('SIGINT'));
process.on('SIGTERM', () => shutdown('SIGTERM'));

// Start server
const transport = new StdioServerTransport();
server.connect(transport).catch((error) => {
  console.error('❌ Failed to start Twilio MCP server:', error);
  process.exit(1);
});

console.error('🚀 Twilio MCP Server running on stdio');
console.error('📱 Ready to handle SMS, voice, verify, conversations, and lookups');