main.cpp

#include <getopt.h>
#include <string>
#include <sstream>

#include "config.h"
#include <mxx/comm.hpp>
#include <mxx/env.hpp>
#include "Driver.h"
#include "JSON/JSONLoader.h"
#include "Drivers/DriverException.h"

using namespace SSAGES;
using namespace Json;

int main(int argc, char* argv[])
{
    // Let MPI collect command line arguments pertaining to MPI.
    mxx::env env(argc, argv);
    mxx::env::set_exception_on_error();
    auto world = mxx::comm();

    std::stringstream helpStream;
    helpStream
        << "Welcome to SSAGES - Suite for Advanced Generalized Ensemble Simulations\n"
        << "\n"
        << argv[0] << " [-h | --help] [ --version ] InputFile.json\n"
        << "\n"
        << "Required parameters:\n"
        << "InputFile.json - Input file specifying the generalized ensemble method and\n"
        << "                 all required input parameters in the JSON format. For more\n"
        << "                 information on the input file, confer the user manual.\n"
        << "\n"
        << "Optional parameters:\n"
        << " -h | --help - Print this help message\n"
        << " --version   - Print SSAGES version and quit\n";

    std::stringstream versionStream;
    versionStream << "SSAGES version " << SSAGES_VERSION_MAJOR << "."
                                       << SSAGES_VERSION_MINOR << "."
                                       << SSAGES_VERSION_TINY << "\n";

    // Define short options, e.g. -h
    const char *OPT_STRING = "h!";

    // Define long options, e.g. --help
    static struct option longOpts[] = {
        { "help", no_argument, NULL, 'h' },
        { "version", no_argument, NULL, '!' },
    };

    // Parse command line arguments
    int optionindex = 1;
    int opt = getopt_long(argc, argv, OPT_STRING, longOpts, &optionindex);

    while (opt != -1) {
        switch (opt) {
        case 'h' :
            std::cout << helpStream.str();
            return 0;
            break;
        case '!' :
            std::cout << versionStream.str();
            return 0;
            break;
        default:
            // getopt_long has already produced an error message
            return 1;
        }
        opt = getopt_long(argc, argv, OPT_STRING, longOpts, &optionindex);
    }

    // Check that there is still one command line option left: The JSON input file
    if (optionindex >= argc) {
        std::cerr << "Error! No JSON input file given. Use " << argv[0] << " --help "
                  << "for information on how to call SSAGES.\n";
        return 2;
    }

    try{
        // Read in input file
        std::string input = argv[optionindex];
        auto json = JSONLoader().LoadFile(input, world);

        // Build driver.
        auto* driver = Driver::Build(json, world);
        driver->Run();  
    } catch(BuildException& e) {
        if(world.rank() == 0)
            DumpErrorsToConsole(e.GetErrors(), 30);
        MPI_Abort(world, -1);
    } catch(std::exception& e) {
        if(world.rank() == 0)       
            DumpErrorsToConsole({e.what()},  30);
        MPI_Abort(world, -1);
    } catch(int& k) { 
        std::string err = strerror(k);
        if(world.rank() == 0)       
            DumpErrorsToConsole({"File IO error: " + err}, 30);
        MPI_Abort(world, -1);
    }
    
    return 0;
}