//-----------------------------------------------------------------------------
/** @file pentobi_gtp/Main.cpp
    @author Markus Enzenberger
    @copyright GNU General Public License version 3 or later */
//-----------------------------------------------------------------------------

#include <fstream>
#include "Engine.h"
#include "libboardgame_util/Log.h"
#include "libboardgame_util/Options.h"
#include "libboardgame_util/RandomGenerator.h"

using namespace std;
using libboardgame_gtp::Failure;
using libboardgame_util::Options;
using libboardgame_util::RandomGenerator;
using libpentobi_base::parse_variant_id;
using libpentobi_base::Board;
using libpentobi_base::Variant;
using libpentobi_mcts::Player;

//-----------------------------------------------------------------------------

namespace {

string get_application_dir_path(int argc, char** argv)
{
    if (argc == 0 || argv == nullptr || argv[0] == nullptr)
        return "";
    string application_path(argv[0]);
#ifdef _WIN32
    auto pos = application_path.find_last_of("/\\");
#else
    auto pos = application_path.find_last_of('/');
#endif
    if (pos == string::npos)
        return "";
    return application_path.substr(0, pos);
}

} // namespace

//-----------------------------------------------------------------------------

int main(int argc, char** argv)
{
    libboardgame_util::LogInitializer log_initializer;
    string application_dir_path = get_application_dir_path(argc, argv);
    try
    {
        vector<string> specs = {
            "book:",
            "config|c:",
            "color",
            "cputime",
            "game|g:",
            "help|h",
            "level|l:",
            "nobook",
            "noresign",
            "quiet|q",
            "seed|r:",
            "showboard",
            "threads:",
            "version|v"
        };
        Options opt(argc, argv, specs);
        if (opt.contains("help"))
        {
            cout <<
                "Usage: pentobi_gtp [options] [input files]\n"
                "--book       load an external book file\n"
                "--config,-c  set GTP config file\n"
                "--color      colorize text output of boards\n"
                "--cputime    use CPU time\n"
                "--game,-g    game variant (classic, classic_2, classic_3,\n"
                "             duo, trigon, trigon_2, trigon_3, junior)\n"
                "--help,-h    print help message and exit\n"
                "--level,-l   set playing strength level\n"
                "--seed,-r    set random seed\n"
                "--showboard  automatically write board to stderr after\n"
                "             changes\n"
                "--nobook     disable opening book\n"
                "--noresign   disable resign\n"
                "--quiet,-q   do not print logging messages\n"
                "--threads    number of threads in the search\n"
                "--version,-v print version and exit\n";
            return 0;
        }
        if (opt.contains("version"))
        {
#ifdef VERSION
            cout << "Pentobi " << VERSION << '\n';
#else
            cout << "Pentobi unknown version";
#endif
            return 0;
        }
        unsigned threads = 1;
        if (opt.contains("threads"))
        {
            threads = opt.get<unsigned>("threads");
            if (threads == 0)
                throw runtime_error("Number of threads must be greater zero.");
        }
        Board::color_output = opt.contains("color");
        if (opt.contains("quiet"))
            libboardgame_util::disable_logging();
        if (opt.contains("seed"))
            RandomGenerator::set_global_seed(
                        opt.get<RandomGenerator::ResultType>("seed"));
        string variant_string = opt.get("game", "classic");
        Variant variant;
        if (! parse_variant_id(variant_string, variant))
            throw runtime_error("invalid game variant " + variant_string);
        auto level = opt.get<unsigned>("level", 4);
        if (level < 1 || level > Player::max_supported_level)
            throw runtime_error("invalid level");
        auto use_book = (! opt.contains("nobook"));
        const string& books_dir = application_dir_path;
        pentobi_gtp::Engine engine(variant, level, use_book, books_dir,
                                   threads);
        engine.set_resign(! opt.contains("noresign"));
        if (opt.contains("showboard"))
            engine.set_show_board(true);
        if (opt.contains("cputime"))
            engine.use_cpu_time(true);
        string book_file = opt.get("book", "");
        if (! book_file.empty())
        {
            ifstream in(book_file);
            engine.get_mcts_player().load_book(in);
        }
        string config_file = opt.get("config", "");
        if (! config_file.empty())
        {
            ifstream in(config_file);
            if (! in)
                throw runtime_error("Error opening " + config_file);
            engine.exec(in, true, libboardgame_util::get_log_stream());
        }
        auto& args = opt.get_args();
        if (! args.empty())
            for (auto& file : args)
            {
                ifstream in(file);
                if (! in)
                    throw runtime_error("Error opening " + file);
                engine.exec_main_loop(in, cout);
            }
        else
            engine.exec_main_loop(cin, cout);
        return 0;
    }
    catch (const Failure& e)
    {
        LIBBOARDGAME_LOG("Error: command in config file failed: ", e.what());
        return 1;
    }
    catch (const exception& e)
    {
        LIBBOARDGAME_LOG("Error: ", e.what());
        return 1;
    }
}

//-----------------------------------------------------------------------------
