#include "path_utils.hpp"
#include <iostream>
#include <optional>
#include <filesystem>
#ifdef _WIN32
# include <windows.h>
# include <tchar.h>
#endif

std::optional<std::filesystem::path> engine::path_utils::exe_path() noexcept {
#if defined(_WIN32)
    TCHAR filename[MAX_PATH];
    if (!GetModuleFileName(NULL, filename, MAX_PATH))
        return {};
    return std::filesystem::path(filename);
#elif defined(linux)
    return std::filesystem::canonical("/proc/self/exe");
#else
# error "operating system not supported"
#endif
}

engine::path_utils::Paths::Paths() noexcept {
    const auto exe_path_opt = engine::path_utils::exe_path();
    if (!exe_path_opt) {
        std::cerr << "cannot find path of executable" << std::endl;
        exit(1);
    }
    const auto files_root = (*exe_path_opt).parent_path();

    m_assets_objs = files_root / std::filesystem::relative(PKGDATADIR "/assets/objs", BINDIR);
    m_assets_textures = files_root / std::filesystem::relative(PKGDATADIR "/assets/textures", BINDIR);
    m_spvshaders = files_root / std::filesystem::relative(SPVSHADERSDIR, BINDIR);
}