#include <cstdlib>
#include <iostream>
#include <SDL2/SDL.h>
#include <vector>

int main(int argc, char** argv) {
	SDL_Init(SDL_INIT_VIDEO);

	int numDisplayModes{ };

	if((numDisplayModes = SDL_GetNumDisplayModes(0)) < 1) {
		std::cerr << "No display modes found." << std::endl;

		SDL_Quit();
		return EXIT_FAILURE;
	}

	std::vector<SDL_DisplayMode> displayModes;

	SDL_DisplayMode currentDisplayMode{ };

	if(SDL_GetCurrentDisplayMode(0, &currentDisplayMode) != 0) {
		std::cerr << "Unable to get details for current display mode." << std::endl;

		SDL_Quit();
		return EXIT_FAILURE;
	}

	displayModes.push_back(currentDisplayMode);

	for(int i{ }; i < numDisplayModes; i++) {
		SDL_DisplayMode newDisplayMode{ };

		if(SDL_GetDisplayMode(0, i, &newDisplayMode) != 0) {
			std::cerr << "Unable to get details for display mode " << i << "." << std::endl;

			SDL_Quit();
			return EXIT_FAILURE;
		}

		displayModes.push_back(newDisplayMode);
	}

	for(const auto displayMode : displayModes) {
		static auto count = 0;

		std::cout << (count++ == 0 ? "Current Resolution " : "Resolution ") << displayMode.w << " x " << displayMode.h << " ";

		auto sdlWindow = SDL_CreateWindow(nullptr, SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, displayMode.w, displayMode.h, SDL_WINDOW_FULLSCREEN | SDL_WINDOW_OPENGL);

		if(sdlWindow == nullptr) {
			std::cout << "FAIL, null pointer";
		} else {
			auto glContext = SDL_GL_CreateContext(sdlWindow);

			int actualWidth{ }, actualHeight{ };

			SDL_GL_GetDrawableSize(sdlWindow, &actualWidth, &actualHeight);

			if(actualWidth != displayMode.w || actualHeight != displayMode.h)
				std::cout << "FAIL, got " << actualWidth << " x " << actualHeight;
			else
				std::cout << "PASS";

			SDL_GL_DeleteContext(glContext);

			SDL_DestroyWindow(sdlWindow);
		}

		std::cout << std::endl;
	}

	SDL_Quit();
	return EXIT_SUCCESS;
}