/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.
 */
#include <cstdlib>
#include <iostream>
#include <boost/bind.hpp>
#include <boost/asio.hpp>
#include <boost/asio/ssl.hpp>

typedef boost::asio::ssl::stream<boost::asio::ip::tcp::socket> ssl_socket;

class session
{
    public:
        session(boost::asio::io_service& io_service, boost::asio::ssl::context& context)
            : socket_(io_service, context)
        {
        }

        ssl_socket::lowest_layer_type& socket()
        {
            return socket_.lowest_layer();
        }

        void start()
        {
            socket_.async_handshake(boost::asio::ssl::stream_base::server,
                    boost::bind(&session::handle_handshake, this,
                        boost::asio::placeholders::error));
        }

        void handle_handshake(const boost::system::error_code& error)
        {
            if (!error)
            {
                socket_.async_read_some(boost::asio::buffer(data_, max_length),
                        boost::bind(&session::handle_read, this,
                            boost::asio::placeholders::error,
                            boost::asio::placeholders::bytes_transferred));
            }
            else
            {
                delete this;
            }
        }

        void handle_read(const boost::system::error_code& error,
                size_t bytes_transferred)
        {
            if (!error)
            {
                boost::asio::async_write(socket_,
                        boost::asio::buffer(data_, bytes_transferred),
                        boost::bind(&session::handle_write, this,
                            boost::asio::placeholders::error));
            }
            else
            {
                delete this;
            }
        }

        void handle_write(const boost::system::error_code& error)
        {
            if (!error)
            {
                socket_.async_read_some(boost::asio::buffer(data_, max_length),
                        boost::bind(&session::handle_read, this,
                            boost::asio::placeholders::error,
                            boost::asio::placeholders::bytes_transferred));
            }
            else
            {
                delete this;
            }
        }

    private:
        ssl_socket socket_;
        enum { max_length = 1024 };
        char data_[max_length];
};

class server
{
    public:
        server(boost::asio::io_service& io_service, unsigned short port)
            : io_service_(io_service),
            acceptor_(io_service,
                    boost::asio::ip::tcp::endpoint(boost::asio::ip::tcp::v4(), port)),
            context_(boost::asio::ssl::context::sslv23)
    {
        context_.set_options(
                boost::asio::ssl::context::default_workarounds
                //| boost::asio::ssl::context::no_sslv2
                | boost::asio::ssl::context::single_dh_use
                );
        context_.set_password_callback(boost::bind(&server::get_password, this));
        context_.use_certificate_chain_file("../../../test/ssl/drillTestCert.pem");
        context_.use_private_key_file("../../../test/ssl/drillTestServerKeyNoPass.pem", boost::asio::ssl::context::pem);
        //context_.use_tmp_dh_file("../../../test/ssl/dh512.pem");

        session* new_session = new session(io_service_, context_);
        acceptor_.async_accept(new_session->socket(),
                boost::bind(&server::handle_accept, this, new_session,
                    boost::asio::placeholders::error));
    }

        std::string get_password() const
        {
            return "test";
        }

        void handle_accept(session* new_session,
                const boost::system::error_code& error)
        {
            if (!error)
            {
                new_session->start();
                new_session = new session(io_service_, context_);
                acceptor_.async_accept(new_session->socket(),
                        boost::bind(&server::handle_accept, this, new_session,
                            boost::asio::placeholders::error));
            }
            else
            {
                delete new_session;
            }
        }

    private:
        boost::asio::io_service& io_service_;
        boost::asio::ip::tcp::acceptor acceptor_;
        boost::asio::ssl::context context_;
};

int main(int argc, char* argv[])
{
    try
    {
        if (argc != 2)
        {
            std::cerr << "Usage: server <port>\n";
            return 1;
        }

        boost::asio::io_service io_service;

        using namespace std; // For atoi.
        server s(io_service, atoi(argv[1]));

        io_service.run();
    }
    catch (std::exception& e)
    {
        std::cerr << "Exception: " << e.what() << "\n";
    }

    return 0;
}