main.cpp

#include <iostream>
#include <memory>
#include <exception>
#include <cstdlib>
#include <SDL2/SDL.h>

#include "simulation.hpp"
#include "pconfig.hpp"

static const int default_fps = 100;

static void usage(const char *appname)
{
    std::cerr << "Usage: " << appname <<
        " <width> <height> <config>" << std::endl;
    exit(EXIT_FAILURE);
}

static void print_speed(int speed)
{
    std::cout << "Speed: " << speed << "x" << std::endl;
}

int main(int argc, char *argv[])
{
    if (argc != 4)
        usage(argv[0]);


    if (SDL_Init(SDL_INIT_VIDEO) != 0) {
        std::cerr << "Failed to init SDL: " << SDL_GetError() << std::endl;
        exit(EXIT_FAILURE);
    }

    SDL_DisplayMode dmode;
    if (SDL_GetDesktopDisplayMode(0, &dmode) != 0) {
        std::cerr << "Failed to get display mode: " << SDL_GetError()
                  << std::endl;
        exit(EXIT_FAILURE);
    }

    int width = strtol(argv[1], NULL, 10);
    int height = strtol(argv[2], NULL, 10);

    if (width < 200 || height < 200) {
        std::cerr << "Width/height can not be less than 200" << std::endl;
        exit(EXIT_FAILURE);
    }
    if (width > dmode.w) {
        std::cerr << "Width can not be greater than " << dmode.w
                  << std::endl;
        exit(EXIT_FAILURE);
    }
    if (height > dmode.h) {
        std::cerr << "Height can not be greater than " << dmode.h
                  << std::endl;
        exit(EXIT_FAILURE);
    }

    try {
        PConfig cfg(argv[3]);
        Simulation simulation(width, height, default_fps);

        while (true) {
            std::unique_ptr<PConfigEntry> entry = cfg.nextEntry();

            if (entry == nullptr)
                break;

            simulation.addParticle(entry->rx, entry->ry, entry->vx, entry->vy,
                                   entry->radius, entry->mass,
                                   entry->r, entry->g, entry->b);
        }

        while (true) {
            SDL_Event event;
            while (SDL_PollEvent(&event)) {
                switch (event.type) {
                case SDL_QUIT:
                    SDL_Quit();
                    return 0;

                case SDL_KEYDOWN:
                    switch (event.key.keysym.sym) {
                    case SDLK_SPACE:
                        if (simulation.paused()) {
                            std::cout << "Resumed" << std::endl;
                            simulation.resume();
                        }
                        else {
                            std::cout << "Paused" << std::endl;
                            simulation.pause();
                        }

                        break;

                    case SDLK_UP:
                        simulation.incSpeed();
                        print_speed(simulation.getSpeed());
                        break;

                    case SDLK_DOWN:
                        simulation.decSpeed();
                        print_speed(simulation.getSpeed());
                        break;
                    }
                }

            }

            simulation.tick();
        }
    }
    catch (PConfigError &e) {
        std::cerr << "Configuration file error: [l: " << e.getLine()
                  << ", c: " << e.getColumn() << "]: " << e.what() << std::endl;
        std::cerr << "Format: " << PConfig::formatString() << std::endl;
        exit(EXIT_FAILURE);
    }
    catch (SimulationError &e) {
        std::cerr << "Simulation error: " << e.what() << std::endl;
        exit(EXIT_FAILURE);
    }
    catch (std::exception &e) {
        std::cerr << "ERROR: " << e.what() << std::endl;
        exit(EXIT_FAILURE);
    }

    exit(EXIT_SUCCESS);
}