// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
//
// A toy server, which listens on a specified address for QUIC traffic and
// handles incoming responses.

#ifndef NET_QUIC_TOOLS_QUIC_SIMPLE_SERVER_H_
#define NET_QUIC_TOOLS_QUIC_SIMPLE_SERVER_H_

#include "base/basictypes.h"
#include "base/memory/scoped_ptr.h"
#include "net/base/io_buffer.h"
#include "net/base/ip_endpoint.h"
#include "net/log/net_log.h"
#include "net/quic/crypto/quic_crypto_server_config.h"
#include "net/quic/quic_clock.h"
#include "net/quic/quic_config.h"
#include "net/quic/quic_connection_helper.h"

namespace net {

class UDPServerSocket;

namespace tools {

class QuicDispatcher;

namespace test {
class QuicSimpleServerPeer;
}  // namespace test

class QuicSimpleServer {
 public:
  QuicSimpleServer(const QuicConfig& config,
                   const QuicVersionVector& supported_versions);

  virtual ~QuicSimpleServer();

  // Start listening on the specified address. Returns an error code.
  int Listen(const IPEndPoint& address);

  // Server deletion is imminent. Start cleaning up.
  void Shutdown();

  // Start reading on the socket. On asynchronous reads, this registers
  // OnReadComplete as the callback, which will then call StartReading again.
  void StartReading();

  // Called on reads that complete asynchronously. Dispatches the packet and
  // continues the read loop.
  void OnReadComplete(int result);

  void SetStrikeRegisterNoStartupPeriod() {
    crypto_config_.set_strike_register_no_startup_period();
  }

  // SetProofSource sets the ProofSource that will be used to verify the
  // server's certificate, and takes ownership of |source|.
  void SetProofSource(ProofSource* source) {
    crypto_config_.SetProofSource(source);
  }

  QuicDispatcher* dispatcher() { return dispatcher_.get(); }

 private:
  friend class test::QuicSimpleServerPeer;

  // Initialize the internal state of the server.
  void Initialize();

  // Accepts data from the framer and demuxes clients to sessions.
  scoped_ptr<QuicDispatcher> dispatcher_;

  // Used by the helper_ to time alarms.
  QuicClock clock_;

  // Used to manage the message loop.
  QuicConnectionHelper helper_;

  // Listening socket. Also used for outbound client communication.
  scoped_ptr<UDPServerSocket> socket_;

  // config_ contains non-crypto parameters that are negotiated in the crypto
  // handshake.
  QuicConfig config_;
  // crypto_config_ contains crypto parameters for the handshake.
  QuicCryptoServerConfig crypto_config_;

  // This vector contains QUIC versions which we currently support.
  // This should be ordered such that the highest supported version is the first
  // element, with subsequent elements in descending order (versions can be
  // skipped as necessary).
  QuicVersionVector supported_versions_;

  // The address that the server listens on.
  IPEndPoint server_address_;

  // Keeps track of whether a read is currently in flight, after which
  // OnReadComplete will be called.
  bool read_pending_;

  // The number of iterations of the read loop that have completed synchronously
  // and without posting a new task to the message loop.
  int synchronous_read_count_;

  // The target buffer of the current read.
  scoped_refptr<IOBufferWithSize> read_buffer_;

  // The source address of the current read.
  IPEndPoint client_address_;

  // The log to use for the socket.
  NetLog net_log_;

  base::WeakPtrFactory<QuicSimpleServer> weak_factory_;

  DISALLOW_COPY_AND_ASSIGN(QuicSimpleServer);
};

}  // namespace tools
}  // namespace net

#endif  // NET_QUIC_TOOLS_QUIC_SIMPLE_SERVER_H_