#include <iostream>
#include <sstream>

#include <boost/date_time/posix_time/posix_time.hpp>
#include <boost/format.hpp>
#include <boost/numeric/conversion/cast.hpp>
#include <boost/test/minimal.hpp>

#include <boost/iostreams/copy.hpp>
#include <boost/iostreams/device/back_inserter.hpp>
#include <boost/iostreams/filter/zlib.hpp>
#include <boost/iostreams/filtering_stream.hpp>

std::string compress(std::string data)
{
    std::stringstream compressed;
    std::stringstream decompressed;
    decompressed << data;
    boost::iostreams::filtering_streambuf<boost::iostreams::input> out;
    out.push(boost::iostreams::zlib_compressor());
    out.push(decompressed);
    boost::iostreams::copy(out, compressed);
    return compressed.str();
}

std::string compress1(const std::string& data)
{
    std::string compressed;
    boost::iostreams::filtering_streambuf<boost::iostreams::output> out;
    out.push(boost::iostreams::zlib_compressor());
    out.push(boost::iostreams::back_inserter(compressed));
    boost::iostreams::copy(boost::make_iterator_range(data), out);
    return compressed;
}

void compress2(const std::string& data, std::string& buffer)
{
    buffer.clear();
    boost::iostreams::filtering_streambuf<boost::iostreams::output> out;
    out.push(boost::iostreams::zlib_compressor());
    out.push(boost::iostreams::back_inserter(buffer));
    boost::iostreams::copy(boost::make_iterator_range(data), out);
}

std::string decompress(std::string data)
{
    std::stringstream compressed;
    std::stringstream decompressed;
    compressed << data;
    boost::iostreams::filtering_streambuf<boost::iostreams::input> in;
    in.push(boost::iostreams::zlib_decompressor());
    in.push(compressed);
    boost::iostreams::copy(in, decompressed);
    return decompressed.str();
}

std::string decompress1(const std::string& data)
{
    boost::iostreams::filtering_streambuf<boost::iostreams::input> in;
    in.push(boost::iostreams::zlib_decompressor());
    in.push(boost::make_iterator_range(data));
    std::string decompressed;
    boost::iostreams::copy(in, boost::iostreams::back_inserter(decompressed));
    return decompressed;
}

void decompress2(const std::string& data, std::string& buffer)
{
    boost::iostreams::filtering_streambuf<boost::iostreams::input> in;
    in.push(boost::iostreams::zlib_decompressor());
    in.push(boost::make_iterator_range(data));
    buffer.clear();
    boost::iostreams::copy(in, boost::iostreams::back_inserter(buffer));
}

boost::posix_time::ptime current_time()
{
    return boost::posix_time::microsec_clock::local_time();
}

double elapsed_seconds(const boost::posix_time::ptime& start_time)
{
    static const double MSEC_PER_SEC = 1000.0;
    boost::posix_time::ptime         end_time = current_time();
    boost::posix_time::time_duration elapsed  = end_time - start_time;
    return boost::numeric_cast<double>(elapsed.total_milliseconds()) / MSEC_PER_SEC;
}

int test_main(int /*argc*/, char* /*argv*/[])
{
    const int NUM_ITERATIONS = 10000;
    const std::string send_data = "boo! how are you?";

    const boost::format time_statement("%1%: %2% cycles took %3% seconds!");
    const boost::format improvement_statement("%1%: Improvement %2% %%");

    double t0;

    // Try original algorithm
    {
        boost::posix_time::ptime start_time = current_time();

        std::string received_data;
        for (int i = 0; i < NUM_ITERATIONS; ++i)
        {
            const std::string buffer = compress(send_data);
            received_data = decompress(buffer);
        }
        BOOST_CHECK(send_data == received_data);

        t0 = elapsed_seconds(start_time);
        std::cout << (boost::format(time_statement) % "ALGO 0 " % NUM_ITERATIONS % t0)
                  << std::endl;
    }

    // Try new algorithm 1
    {
        boost::posix_time::ptime start_time = current_time();

        std::string received_data;
        for (int i = 0; i < NUM_ITERATIONS; ++i)
        {
            const std::string buffer = compress1(send_data);
            received_data = decompress1(buffer);
        }
        BOOST_CHECK(send_data == received_data);

        double e = elapsed_seconds(start_time);
        std::cout << (boost::format(time_statement) % "ALGO 1 " % NUM_ITERATIONS % e)
                  << std::endl;

        double improvement = ((t0 - e) / t0) * 100.0;
        std::cout << (boost::format(improvement_statement) % "ALGO 1 " % improvement)
                  << std::endl;
    }

    // Try new algorithm 2
    {
        boost::posix_time::ptime start_time = current_time();

        std::string received_data;
        for (int i = 0; i < NUM_ITERATIONS; ++i)
        {
            std::string buffer;
            compress2(send_data, buffer);
            decompress2(buffer, received_data);
        }
        BOOST_CHECK(send_data == received_data);

        double e = elapsed_seconds(start_time);
        std::cout << (boost::format(time_statement) % "ALGO 2 " % NUM_ITERATIONS % e)
                  << std::endl;

        double improvement = ((t0 - e) / t0) * 100.0;
        std::cout << (boost::format(improvement_statement) % "ALGO 2 " % improvement)
                  << std::endl;
    }

    return 0;
}