import { expect, tap } from '@push.rocks/tapbundle';
import * as net from 'net';
import { PortProxy } from '../ts/classes.portproxy.js';

let testServer: net.Server;
let portProxy: PortProxy;
const TEST_SERVER_PORT = 4000;
const PROXY_PORT = 4001;
const TEST_DATA = 'Hello through port proxy!';

// Helper function to create a test TCP server
function createTestServer(port: number): Promise<net.Server> {
  return new Promise((resolve) => {
    const server = net.createServer((socket) => {
      socket.on('data', (data) => {
        // Echo the received data back
        socket.write(`Echo: ${data.toString()}`);
      });
      socket.on('error', (error) => {
        console.error('[Test Server] Socket error:', error);
      });
    });
    server.listen(port, () => {
      console.log(`[Test Server] Listening on port ${port}`);
      resolve(server);
    });
  });
}

// Helper function to create a test client connection
function createTestClient(port: number, data: string): Promise<string> {
  return new Promise((resolve, reject) => {
    const client = new net.Socket();
    let response = '';

    client.connect(port, 'localhost', () => {
      console.log('[Test Client] Connected to server');
      client.write(data);
    });
    client.on('data', (chunk) => {
      response += chunk.toString();
      client.end();
    });
    client.on('end', () => {
      resolve(response);
    });
    client.on('error', (error) => {
      reject(error);
    });
  });
}

// Setup test environment
tap.test('setup port proxy test environment', async () => {
  testServer = await createTestServer(TEST_SERVER_PORT);
  portProxy = new PortProxy({
    fromPort: PROXY_PORT,
    toPort: TEST_SERVER_PORT,
    targetIP: 'localhost',
    domains: [],
    sniEnabled: false,
    defaultAllowedIPs: ['127.0.0.1'],
    globalPortRanges: []
  });
});

tap.test('should start port proxy', async () => {
  await portProxy.start();
  // Since netServers is private, we cast to any to verify that all created servers are listening.
  expect((portProxy as any).netServers.every((server: net.Server) => server.listening)).toBeTrue();
});

tap.test('should forward TCP connections and data to localhost', async () => {
  const response = await createTestClient(PROXY_PORT, TEST_DATA);
  expect(response).toEqual(`Echo: ${TEST_DATA}`);
});

tap.test('should forward TCP connections to custom host', async () => {
  // Create a new proxy instance with a custom host (targetIP)
  const customHostProxy = new PortProxy({
    fromPort: PROXY_PORT + 1,
    toPort: TEST_SERVER_PORT,
    targetIP: '127.0.0.1',
    domains: [],
    sniEnabled: false,
    defaultAllowedIPs: ['127.0.0.1'],
    globalPortRanges: []
  });
  
  await customHostProxy.start();
  const response = await createTestClient(PROXY_PORT + 1, TEST_DATA);
  expect(response).toEqual(`Echo: ${TEST_DATA}`);
  await customHostProxy.stop();
});

tap.test('should forward connections based on domain-specific target IP', async () => {
  // Create a second test server on a different port
  const TEST_SERVER_PORT_2 = TEST_SERVER_PORT + 100;
  const testServer2 = await createTestServer(TEST_SERVER_PORT_2);

  // Create a proxy with domain-specific target IPs
  const domainProxy = new PortProxy({
    fromPort: PROXY_PORT + 2,
    toPort: TEST_SERVER_PORT,  // default port (for non-port-range handling)
    targetIP: 'localhost',     // default target IP
    domains: [{
      domain: 'domain1.test',
      allowedIPs: ['127.0.0.1'],
      targetIP: '127.0.0.1'
    }, {
      domain: 'domain2.test',
      allowedIPs: ['127.0.0.1'],
      targetIP: 'localhost'
    }],
    sniEnabled: false,
    defaultAllowedIPs: ['127.0.0.1'],
    globalPortRanges: []
  });

  await domainProxy.start();

  // Test default connection (should use default targetIP)
  const response1 = await createTestClient(PROXY_PORT + 2, TEST_DATA);
  expect(response1).toEqual(`Echo: ${TEST_DATA}`);

  // Create another proxy with a different default targetIP
  const domainProxy2 = new PortProxy({
    fromPort: PROXY_PORT + 3,
    toPort: TEST_SERVER_PORT,
    targetIP: '127.0.0.1',
    domains: [],
    sniEnabled: false,
    defaultAllowedIPs: ['127.0.0.1'],
    globalPortRanges: []
  });

  await domainProxy2.start();
  const response2 = await createTestClient(PROXY_PORT + 3, TEST_DATA);
  expect(response2).toEqual(`Echo: ${TEST_DATA}`);

  await domainProxy.stop();
  await domainProxy2.stop();
  await new Promise<void>((resolve) => testServer2.close(() => resolve()));
});

tap.test('should handle multiple concurrent connections', async () => {
  const concurrentRequests = 5;
  const requests = Array(concurrentRequests).fill(null).map((_, i) => 
    createTestClient(PROXY_PORT, `${TEST_DATA} ${i + 1}`)
  );
  
  const responses = await Promise.all(requests);
  
  responses.forEach((response, i) => {
    expect(response).toEqual(`Echo: ${TEST_DATA} ${i + 1}`);
  });
});

tap.test('should handle connection timeouts', async () => {
  const client = new net.Socket();
  await new Promise<void>((resolve) => {
    client.connect(PROXY_PORT, 'localhost', () => {
      // Don't send any data, just wait for timeout
      client.on('close', () => {
        resolve();
      });
    });
  });
});

tap.test('should stop port proxy', async () => {
  await portProxy.stop();
  expect((portProxy as any).netServers.every((server: net.Server) => !server.listening)).toBeTrue();
});

// Cleanup chained proxies tests
tap.test('should support optional source IP preservation in chained proxies', async () => {
  // Test 1: Without IP preservation (default behavior)
  const firstProxyDefault = new PortProxy({
    fromPort: PROXY_PORT + 4,
    toPort: PROXY_PORT + 5,
    targetIP: 'localhost',
    domains: [],
    sniEnabled: false,
    defaultAllowedIPs: ['127.0.0.1', '::ffff:127.0.0.1'],
    globalPortRanges: []
  });

  const secondProxyDefault = new PortProxy({
    fromPort: PROXY_PORT + 5,
    toPort: TEST_SERVER_PORT,
    targetIP: 'localhost',
    domains: [],
    sniEnabled: false,
    defaultAllowedIPs: ['127.0.0.1', '::ffff:127.0.0.1'],
    globalPortRanges: []
  });

  await secondProxyDefault.start();
  await firstProxyDefault.start();

  // This should work because we explicitly allow both IPv4 and IPv6 formats
  const response1 = await createTestClient(PROXY_PORT + 4, TEST_DATA);
  expect(response1).toEqual(`Echo: ${TEST_DATA}`);

  await firstProxyDefault.stop();
  await secondProxyDefault.stop();

  // Test 2: With IP preservation
  const firstProxyPreserved = new PortProxy({
    fromPort: PROXY_PORT + 6,
    toPort: PROXY_PORT + 7,
    targetIP: 'localhost',
    domains: [],
    sniEnabled: false,
    defaultAllowedIPs: ['127.0.0.1'],
    preserveSourceIP: true,
    globalPortRanges: []
  });

  const secondProxyPreserved = new PortProxy({
    fromPort: PROXY_PORT + 7,
    toPort: TEST_SERVER_PORT,
    targetIP: 'localhost',
    domains: [],
    sniEnabled: false,
    defaultAllowedIPs: ['127.0.0.1'],
    preserveSourceIP: true,
    globalPortRanges: []
  });

  await secondProxyPreserved.start();
  await firstProxyPreserved.start();

  // This should work with just IPv4 because source IP is preserved
  const response2 = await createTestClient(PROXY_PORT + 6, TEST_DATA);
  expect(response2).toEqual(`Echo: ${TEST_DATA}`);

  await firstProxyPreserved.stop();
  await secondProxyPreserved.stop();
});

tap.test('cleanup port proxy test environment', async () => {
  await new Promise<void>((resolve) => testServer.close(() => resolve()));
});

process.on('exit', () => {
  if (testServer) {
    testServer.close();
  }
  // Use a cast to access the private property for cleanup.
  if (portProxy && (portProxy as any).netServers) {
    portProxy.stop();
  }
});

export default tap.start();