// Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
//
// VMOptions=
// VMOptions=--short_socket_read
// VMOptions=--short_socket_write
// VMOptions=--short_socket_read --short_socket_write
// OtherResources=certificates/server_chain.pem
// OtherResources=certificates/server_key.pem
// OtherResources=certificates/trusted_certs.pem
// OtherResources=certificates/untrusted_server_chain.pem
// OtherResources=certificates/untrusted_server_key.pem

import "dart:async";
import "dart:io";

import "package:async_helper/async_helper.dart";
import "package:expect/expect.dart";

late InternetAddress HOST;
String localFile(path) => Platform.script.resolve(path).toFilePath();

SecurityContext serverContext = new SecurityContext()
  ..useCertificateChain(localFile('certificates/server_chain.pem'))
  ..usePrivateKey(localFile('certificates/server_key.pem'),
      password: 'dartdart');

SecurityContext clientContext = new SecurityContext()
  ..setTrustedCertificates(localFile('certificates/trusted_certs.pem'));

void testSimpleBind() {
  print("asyncStart testSimpleBind");
  asyncStart();
  RawSecureServerSocket.bind(HOST, 0, serverContext).then((s) {
    Expect.isTrue(s.port > 0);
    s.close();
    print("asyncEnd testSimpleBind");
    asyncEnd();
  });
}

void testInvalidBind() {
  int count = 0;

  // Bind to a unknown DNS name.
  asyncStart();
  print("asyncStart testInvalidBind");
  RawSecureServerSocket.bind("ko.faar.__hest__", 0, serverContext).then((_) {
    Expect.fail("Failure expected");
  }).catchError((error) {
    Expect.isTrue(error is SocketException);
    print("asyncEnd testInvalidBind");
    asyncEnd();
  });

  // Bind to an unavaliable IP-address.
  asyncStart();
  print("asyncStart testInvalidBind 2");
  RawSecureServerSocket.bind("8.8.8.8", 0, serverContext).then((_) {
    Expect.fail("Failure expected");
  }).catchError((error) {
    Expect.isTrue(error is SocketException);
    print("asyncEnd testInvalidBind 2");
    asyncEnd();
  });

  // Bind to a port already in use.
  asyncStart();
  print("asyncStart testInvalidBind 3");
  RawSecureServerSocket.bind(HOST, 0, serverContext).then((s) {
    RawSecureServerSocket.bind(HOST, s.port, serverContext).then((t) {
      s.close();
      t.close();
      Expect.fail("Multiple listens on same port");
    }).catchError((error) {
      Expect.isTrue(error is SocketException);
      s.close();
      print("asyncEnd testInvalidBind 3");
      asyncEnd();
    });
  });
}

void testSimpleConnect() {
  print("asyncStart testSimpleConnect");
  asyncStart();
  RawSecureServerSocket.bind(HOST, 0, serverContext).then((server) {
    var clientEndFuture =
        RawSecureSocket.connect(HOST, server.port, context: clientContext);
    server.listen((serverEnd) {
      clientEndFuture.then((clientEnd) {
        // TODO(whesse): Shutdown(SEND) not supported on secure sockets.
        clientEnd.shutdown(SocketDirection.send);
        serverEnd.shutdown(SocketDirection.send);
        server.close();
        print("asyncEnd testSimpleConnect");
        asyncEnd();
      });
    });
  });
}

int debugTestSimpleConnectFailCounter = 0;
void testSimpleConnectFail(SecurityContext context, bool cancelOnError) {
  var counter = debugTestSimpleConnectFailCounter++;
  print("asyncStart testSimpleConnectFail $counter");
  asyncStart();
  RawSecureServerSocket.bind(HOST, 0, context).then((server) {
    Future<void> clientEndFuture =
        RawSecureSocket.connect(HOST, server.port, context: clientContext)
            .then((clientEnd) {
      Expect.fail("No client connection expected.");
    }).catchError((error) {
      Expect.isTrue(error is SocketException || error is HandshakeException);
    });
    server.listen((serverEnd) {
      Expect.fail("No server connection expected.");
    }, onError: (error) {
      Expect.isTrue(error is SocketException || error is HandshakeException);
      clientEndFuture.then((_) {
        if (!cancelOnError) server.close();
        print("asyncEnd testSimpleConnectFail $counter");
        asyncEnd();
      });
    }, cancelOnError: cancelOnError);
  });
}

void testServerListenAfterConnect() {
  print("asyncStart testServerListenAfterConnect");
  asyncStart();
  RawSecureServerSocket.bind(HOST, 0, serverContext).then((server) {
    Expect.isTrue(server.port > 0);
    var clientEndFuture =
        RawSecureSocket.connect(HOST, server.port, context: clientContext);
    new Timer(const Duration(milliseconds: 500), () {
      server.listen((serverEnd) {
        clientEndFuture.then((clientEnd) {
          clientEnd.shutdown(SocketDirection.send);
          serverEnd.shutdown(SocketDirection.send);
          server.close();
          print("asyncEnd testServerListenAfterConnect");
          asyncEnd();
        });
      });
    });
  });
}

// This test creates a server and a client connects. The client then
// writes and the server echos. When the server has finished its echo
// it half-closes. When the client gets the close event is closes
// fully.
//
// The test can be run in different configurations based on
// the boolean arguments:
//
// listenSecure
// When this argument is true a secure server is used. When this is false
// a non-secure server is used and the connections are secured after being
// connected.
//
// connectSecure
// When this argument is true a secure client connection is used. When this
// is false a non-secure client connection is used and the connection is
// secured after being connected.
//
// handshakeBeforeSecure
// When this argument is true some initial clear text handshake is done
// between client and server before the connection is secured. This argument
// only makes sense when both listenSecure and connectSecure are false.
//
// postponeSecure
// When this argument is false the securing of the server end will
// happen as soon as the last byte of the handshake before securing
// has been written. When this argument is true the securing of the
// server will not happen until the first TLS handshake data has been
// received from the client. This argument only takes effect when
// handshakeBeforeSecure is true.
void testSimpleReadWrite(
    {required bool listenSecure,
    required bool connectSecure,
    required bool handshakeBeforeSecure,
    required bool postponeSecure,
    required bool dropReads}) {
  int clientReads = 0;
  int serverReads = 0;
  if (handshakeBeforeSecure == true &&
      (listenSecure == true || connectSecure == true)) {
    Expect.fail("Invalid arguments to testSimpleReadWrite");
  }

  print("asyncStart testSimpleReadWrite($listenSecure, $connectSecure, "
      "$handshakeBeforeSecure, $postponeSecure, $dropReads");
  asyncStart();

  const messageSize = 1000;
  const handshakeMessageSize = 100;

  List<int> createTestData() {
    List<int> data = new List<int>.filled(messageSize, 0);
    for (int i = 0; i < messageSize; i++) {
      data[i] = i & 0xff;
    }
    return data;
  }

  List<int> createHandshakeTestData() {
    List<int> data = new List<int>.filled(handshakeMessageSize, 0);
    for (int i = 0; i < handshakeMessageSize; i++) {
      data[i] = i & 0xff;
    }
    return data;
  }

  void verifyTestData(List<int> data) {
    Expect.equals(messageSize, data.length);
    List<int> expected = createTestData();
    for (int i = 0; i < messageSize; i++) {
      Expect.equals(expected[i], data[i]);
    }
  }

  void verifyHandshakeTestData(List<int> data) {
    Expect.equals(handshakeMessageSize, data.length);
    List<int> expected = createHandshakeTestData();
    for (int i = 0; i < handshakeMessageSize; i++) {
      Expect.equals(expected[i], data[i]);
    }
  }

  Future runServer(RawSocket client) {
    var completer = new Completer();
    int bytesRead = 0;
    int bytesWritten = 0;
    List<int> data = new List<int>.filled(messageSize, 0);
    client.writeEventsEnabled = false;
    var subscription;
    subscription = client.listen((event) {
      switch (event) {
        case RawSocketEvent.read:
          if (dropReads) {
            if (serverReads != 10) {
              ++serverReads;
              break;
            } else {
              serverReads = 0;
            }
          }
          Expect.isTrue(bytesWritten == 0);
          Expect.isTrue(client.available() > 0);
          var buffer = client.read();
          if (buffer != null) {
            data.setRange(bytesRead, bytesRead + buffer.length, buffer);
            bytesRead += buffer.length;
            for (var value in buffer) {
              Expect.isTrue(value is int);
              Expect.isTrue(value < 256 && value >= 0);
            }
          }
          if (bytesRead == data.length) {
            verifyTestData(data);
            client.writeEventsEnabled = true;
          }
          break;
        case RawSocketEvent.write:
          Expect.isFalse(client.writeEventsEnabled);
          Expect.equals(bytesRead, data.length);
          for (int i = bytesWritten; i < data.length; ++i) {
            Expect.isTrue(data[i] is int);
            Expect.isTrue(data[i] < 256 && data[i] >= 0);
          }
          bytesWritten +=
              client.write(data, bytesWritten, data.length - bytesWritten);
          if (bytesWritten < data.length) {
            client.writeEventsEnabled = true;
          }
          if (bytesWritten == data.length) {
            client.shutdown(SocketDirection.send);
          }
          break;
        case RawSocketEvent.readClosed:
          completer.complete(null);
          break;
        default:
          throw "Unexpected event $event";
      }
    });
    return completer.future;
  }

  Future<RawSocket> runClient(RawSocket socket) {
    var completer = new Completer<RawSocket>();
    int bytesRead = 0;
    int bytesWritten = 0;
    List<int> dataSent = createTestData();
    List<int> dataReceived = new List<int>.filled(dataSent.length, 0);
    socket.listen((event) {
      switch (event) {
        case RawSocketEvent.read:
          Expect.isTrue(socket.available() > 0);
          if (dropReads) {
            if (clientReads != 10) {
              ++clientReads;
              break;
            } else {
              clientReads = 0;
            }
          }
          var buffer = socket.read();
          if (buffer != null) {
            dataReceived.setRange(bytesRead, bytesRead + buffer.length, buffer);
            bytesRead += buffer.length;
          }
          break;
        case RawSocketEvent.write:
          Expect.isTrue(bytesRead == 0);
          Expect.isFalse(socket.writeEventsEnabled);
          bytesWritten += socket.write(
              dataSent, bytesWritten, dataSent.length - bytesWritten);
          if (bytesWritten < dataSent.length) {
            socket.writeEventsEnabled = true;
          }
          break;
        case RawSocketEvent.readClosed:
          verifyTestData(dataReceived);
          completer.complete(socket);
          break;
        default:
          throw "Unexpected event $event";
      }
    });
    return completer.future;
  }

  Future runServerHandshake(RawSocket client) {
    var completer = new Completer();
    int bytesRead = 0;
    int bytesWritten = 0;
    List<int> data = new List<int>.filled(handshakeMessageSize, 0);
    client.writeEventsEnabled = false;
    var subscription;
    subscription = client.listen((event) {
      switch (event) {
        case RawSocketEvent.read:
          if (bytesRead < data.length) {
            Expect.isTrue(bytesWritten == 0);
          }
          Expect.isTrue(client.available() > 0);
          if (dropReads) {
            if (serverReads != 10) {
              ++serverReads;
              break;
            } else {
              serverReads = 0;
            }
          }
          var buffer = client.read();
          if (buffer != null) {
            if (bytesRead == data.length) {
              // Read first part of TLS handshake from client.
              Expect.isTrue(postponeSecure);
              completer.complete([subscription, buffer]);
              client.readEventsEnabled = false;
              return;
            }
            data.setRange(bytesRead, bytesRead + buffer.length, buffer);
            bytesRead += buffer.length;
            for (var value in buffer) {
              Expect.isTrue(value is int);
              Expect.isTrue(value < 256 && value >= 0);
            }
          }
          if (bytesRead == data.length) {
            verifyHandshakeTestData(data);
            client.writeEventsEnabled = true;
          }
          break;
        case RawSocketEvent.write:
          Expect.isFalse(client.writeEventsEnabled);
          Expect.equals(bytesRead, data.length);
          for (int i = bytesWritten; i < data.length; ++i) {
            Expect.isTrue(data[i] is int);
            Expect.isTrue(data[i] < 256 && data[i] >= 0);
          }
          bytesWritten +=
              client.write(data, bytesWritten, data.length - bytesWritten);
          if (bytesWritten < data.length) {
            client.writeEventsEnabled = true;
          }
          if (bytesWritten == data.length) {
            if (!postponeSecure) {
              completer.complete([subscription, null]);
            }
          }
          break;
        case RawSocketEvent.readClosed:
          Expect.fail("Unexpected close");
          break;
        default:
          throw "Unexpected event $event";
      }
    });
    return completer.future;
  }

  Future<StreamSubscription<RawSocketEvent>> runClientHandshake(
      RawSocket socket) {
    var completer = new Completer<StreamSubscription<RawSocketEvent>>();
    int bytesRead = 0;
    int bytesWritten = 0;
    List<int> dataSent = createHandshakeTestData();
    List<int> dataReceived = new List<int>.filled(dataSent.length, 0);
    var subscription;
    subscription = socket.listen((event) {
      switch (event) {
        case RawSocketEvent.read:
          if (dropReads) {
            if (clientReads != 10) {
              ++clientReads;
              break;
            } else {
              clientReads = 0;
            }
          }
          Expect.isTrue(socket.available() > 0);
          var buffer = socket.read();
          if (buffer != null) {
            dataReceived.setRange(bytesRead, bytesRead + buffer.length, buffer);
            bytesRead += buffer.length;
            if (bytesRead == dataSent.length) {
              verifyHandshakeTestData(dataReceived);
              completer.complete(subscription);
            }
          }
          break;
        case RawSocketEvent.write:
          Expect.isTrue(bytesRead == 0);
          Expect.isFalse(socket.writeEventsEnabled);
          bytesWritten += socket.write(
              dataSent, bytesWritten, dataSent.length - bytesWritten);
          if (bytesWritten < dataSent.length) {
            socket.writeEventsEnabled = true;
          }
          break;
        case RawSocketEvent.readClosed:
          Expect.fail("Unexpected close");
          break;
        default:
          throw "Unexpected event $event";
      }
    });
    return completer.future;
  }

  Future<RawSecureSocket> connectClient(int port) {
    if (connectSecure) {
      return RawSecureSocket.connect(HOST, port, context: clientContext);
    } else if (!handshakeBeforeSecure) {
      return RawSocket.connect(HOST, port).then((socket) {
        return RawSecureSocket.secure(socket, context: clientContext);
      });
    } else {
      return RawSocket.connect(HOST, port).then((socket) {
        return runClientHandshake(socket).then((subscription) {
          return RawSecureSocket.secure(socket,
              context: clientContext, subscription: subscription);
        });
      });
    }
  }

  serverReady(server) {
    server.listen((client) {
      if (listenSecure) {
        runServer(client).then((_) => server.close());
      } else if (!handshakeBeforeSecure) {
        RawSecureSocket.secureServer(client, serverContext).then((client) {
          runServer(client).then((_) => server.close());
        });
      } else {
        runServerHandshake(client).then((secure) {
          RawSecureSocket.secureServer(client, serverContext,
                  subscription: secure[0], bufferedData: secure[1])
              .then((client) {
            runServer(client).then((_) => server.close());
          });
        });
      }
    });

    connectClient(server.port).then(runClient).then((socket) {
      socket.close();
      print("asyncEnd testSimpleReadWrite($listenSecure, $connectSecure, "
          "$handshakeBeforeSecure, $postponeSecure, $dropReads");
      asyncEnd();
    });
  }

  if (listenSecure) {
    RawSecureServerSocket.bind(HOST, 0, serverContext).then(serverReady);
  } else {
    RawServerSocket.bind(HOST, 0).then(serverReady);
  }
}

testPausedSecuringSubscription(bool pausedServer, bool pausedClient) {
  print(
      "asyncStart testPausedSecuringSubscription $pausedServer $pausedClient");
  asyncStart();
  var clientComplete = new Completer();
  RawServerSocket.bind(HOST, 0).then((server) {
    server.listen((client) {
      var subscription;
      subscription = client.listen((_) {
        if (pausedServer) {
          subscription.pause();
        }
        void done() {
          server.close();
          clientComplete.future.then((_) {
            client.close();
            print("asyncEnd testPausedSecuringSubscription "
                "$pausedServer $pausedClient");
            asyncEnd();
          });
        }

        try {
          Future<RawSecureSocket?>.value(RawSecureSocket.secureServer(
                  client, serverContext,
                  subscription: subscription))
              .catchError((_) {})
              .whenComplete(() {
            if (pausedServer) {
              Expect.fail("secureServer succeeded with paused subscription");
            }
            done();
          });
        } catch (e) {
          if (!pausedServer) {
            Expect.fail("secureServer failed with non-paused subscriptions");
          }
          if (pausedServer) {
            Expect.isTrue(e is ArgumentError);
          }
          done();
        }
      });
    });

    RawSocket.connect(HOST, server.port).then((socket) {
      var subscription;
      subscription = socket.listen((_) {
        if (pausedClient) {
          subscription.pause();
        }
        try {
          Future<RawSecureSocket?>.value(
                  RawSecureSocket.secure(socket, subscription: subscription))
              .catchError((_) {})
              .whenComplete(() {
            if (pausedClient) {
              Expect.fail("secure succeeded with paused subscription");
            }
            socket.close();
            clientComplete.complete(null);
          });
        } catch (e) {
          if (!pausedClient) {
            Expect.fail("secure failed with non-paused subscriptions ($e)");
          }
          if (pausedClient) {
            Expect.isTrue(e is ArgumentError);
          }
          clientComplete.complete(null);
        }
      });
    });
  });
}

main() {
  print("asyncStart main");
  asyncStart();
  InternetAddress.lookup("localhost").then((hosts) {
    HOST = hosts.first;
    runTests();
    print("asyncEnd main");
    asyncEnd();
  });
}

runTests() {
  testSimpleBind();
  testInvalidBind();
  testSimpleConnect();
  SecurityContext context = new SecurityContext();
  testSimpleConnectFail(context, false);
  testSimpleConnectFail(context, true);
  var chain = Platform.script
      .resolve('certificates/untrusted_server_chain.pem')
      .toFilePath();
  context.useCertificateChain(chain);
  testSimpleConnectFail(context, false);
  testSimpleConnectFail(context, true);
  var key = Platform.script
      .resolve('certificates/untrusted_server_key.pem')
      .toFilePath();
  context.usePrivateKey(key, password: 'dartdart');
  testSimpleConnectFail(context, false);
  testSimpleConnectFail(context, true);
  testServerListenAfterConnect();

  testSimpleReadWrite(
      listenSecure: true,
      connectSecure: true,
      handshakeBeforeSecure: false,
      postponeSecure: false,
      dropReads: false);
  testSimpleReadWrite(
      listenSecure: true,
      connectSecure: false,
      handshakeBeforeSecure: false,
      postponeSecure: false,
      dropReads: false);

  testSimpleReadWrite(
      listenSecure: false,
      connectSecure: true,
      handshakeBeforeSecure: false,
      postponeSecure: false,
      dropReads: false);

  testSimpleReadWrite(
      listenSecure: false,
      connectSecure: false,
      handshakeBeforeSecure: false,
      postponeSecure: false,
      dropReads: false);
  testSimpleReadWrite(
      listenSecure: false,
      connectSecure: false,
      handshakeBeforeSecure: true,
      postponeSecure: true,
      dropReads: false);
  testSimpleReadWrite(
      listenSecure: false,
      connectSecure: false,
      handshakeBeforeSecure: true,
      postponeSecure: false,
      dropReads: false);
  testSimpleReadWrite(
      listenSecure: true,
      connectSecure: true,
      handshakeBeforeSecure: false,
      postponeSecure: false,
      dropReads: true);
  testSimpleReadWrite(
      listenSecure: false,
      connectSecure: false,
      handshakeBeforeSecure: true,
      postponeSecure: true,
      dropReads: true);
  testPausedSecuringSubscription(false, false);
  testPausedSecuringSubscription(true, false);
  testPausedSecuringSubscription(false, true);
  testPausedSecuringSubscription(true, true);
}