////////////////////////////////////////////////////////////////////////////////
/// DISCLAIMER
///
/// Copyright 2016 ArangoDB GmbH, Cologne, Germany
///
/// Licensed under the Apache License, Version 2.0 (the "License");
/// you may not use this file except in compliance with the License.
/// You may obtain a copy of the License at
///
///     http://www.apache.org/licenses/LICENSE-2.0
///
/// Unless required by applicable law or agreed to in writing, software
/// distributed under the License is distributed on an "AS IS" BASIS,
/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
/// See the License for the specific language governing permissions and
/// limitations under the License.
///
/// Copyright holder is ArangoDB GmbH, Cologne, Germany
///
/// @author Dr. Frank Celler
////////////////////////////////////////////////////////////////////////////////

#ifndef ARANGOD_SCHEDULER_SOCKET_H
#define ARANGOD_SCHEDULER_SOCKET_H 1

#include "Basics/Common.h"

#include <boost/asio/basic_stream_socket.hpp>
#include <boost/asio/serial_port_service.hpp>
#include <boost/asio/ssl.hpp>

#include "Basics/asio-helper.h"
#include "Basics/StringBuffer.h"
#include "Logger/Logger.h"

namespace arangodb {

typedef std::function<void(const boost::system::error_code& ec,
    std::size_t transferred)> AsyncHandler;

namespace socketcommon {
  template<typename T>
  bool doSslHandshake(T &socket) {
    boost::system::error_code ec;
    
    do {
      ec.assign(boost::system::errc::success,
          boost::system::generic_category());
      socket.handshake(
          boost::asio::ssl::stream_base::handshake_type::server, ec);
    } while (ec.value() == boost::asio::error::would_block);
      
    if (ec) {
      LOG_TOPIC(ERR, Logger::COMMUNICATION)
          << "unable to perform ssl handshake: " << ec.message() << " : "
          << ec.value();
      return false;
    }
    return true;
  }
  
  template<typename T>
  size_t doWrite(T& socket, basics::StringBuffer* buffer, boost::system::error_code& ec) {
    return socket.write_some(boost::asio::buffer(buffer->begin(), buffer->length()), ec);
  }
  template<typename T>
  void doAsyncWrite(T& socket, boost::asio::mutable_buffers_1 const& buffer, AsyncHandler const& handler) {
    return boost::asio::async_write(socket, buffer, handler);
  }
  template<typename T>
  size_t doRead(T& socket, boost::asio::mutable_buffers_1 const& buffer, boost::system::error_code& ec) {
    return socket.read_some(buffer, ec);
  }
  template<typename T>
  void doAsyncRead(T& socket, boost::asio::mutable_buffers_1 const& buffer, AsyncHandler const& handler) {
    return socket.async_read_some(buffer, handler);
  }
}

class Socket {
  public:
    Socket(boost::asio::io_service& ioService,
           boost::asio::ssl::context&& context, bool encrypted)
        : _ioService(ioService),
          _context(std::move(context)),
          _encrypted(encrypted) {}
    Socket(Socket&& that) = default;
    virtual ~Socket() {}
    
    virtual void close() = 0;
    virtual void close(boost::system::error_code& ec) = 0;
    virtual void setNonBlocking(bool) = 0;
    virtual std::string peerAddress() = 0;
    virtual int peerPort() = 0;
    bool handshake();
    virtual size_t write(basics::StringBuffer* buffer, boost::system::error_code& ec) = 0;
    virtual void asyncWrite(boost::asio::mutable_buffers_1 const& buffer, AsyncHandler const& handler) = 0;
    virtual size_t read(boost::asio::mutable_buffers_1 const& buffer, boost::system::error_code& ec) = 0;
    virtual void shutdownReceive() = 0; 
    virtual void shutdownReceive(boost::system::error_code& ec) = 0; 
    virtual void shutdownSend(boost::system::error_code& ec) = 0; 
    virtual int available(boost::system::error_code& ec) = 0; 
    virtual void asyncRead(boost::asio::mutable_buffers_1 const& buffer, AsyncHandler const& handler) = 0;

  protected:
    virtual bool sslHandshake() = 0;
     
  public:
    boost::asio::io_service& _ioService;
    boost::asio::ssl::context _context;

    bool _encrypted;
  
};
}

#endif