#include "configpp.hpp"

#include <boost/filesystem/path.hpp>
#include <boost/filesystem/operations.hpp>
#include <boost/property_tree/json_parser.hpp>

#include <fstream>

namespace configpp {

std::unique_ptr<Config> Config::config_ptr = nullptr;

#if defined( _WIN32 ) || defined( _WIN64 )
boost::filesystem::path get_config_base_dir() {
	if(!std::getenv("APPDATA")) {
		throw std::runtime_error("Environment variable \"APPDATA\" is not set, could not find suitable config home.");
	}
	boost::filesystem::path appdata(std::getenv("APPDATA"));
	return appdata
}
#endif

#if defined( __unix__ ) && !defined( __APPLE__) && !defined( __MACH__ )
boost::filesystem::path get_config_base_dir() {
	boost::filesystem::path config_home;
	boost::filesystem::path path;
	if(!std::getenv("XDG_CONFIG_HOME")) {
		if(!std::getenv("HOME")) {
			throw std::runtime_error("Neither \"XDG_CONFIG_HOME\" nor \"HOME\" environment variable are set, could not find suitable config home.");
		} else {
			config_home = getenv("HOME");
			path = config_home / boost::filesystem::path(".config");
		}
	} else {
		path = getenv("XDG_CONFIG_HOME");
	}
	return path;
}

#endif

#if defined( __APPLE__ ) && defined( __MACH__ )
boost::filesystem::path get_config_base_dir(std::string subdir) {
	boost::filesystem::path path;
	if(!std::getenv("HOME")) {
		throw std::runtime_error("\"HOME\" environment variable is not set, could not find a suitable config home.");
	} else {
		path = boost::filesystem::path(std::getenv("HOME"));
	}
	return path;
}
#endif

using namespace boost::filesystem;

Config::Config(std::string subdir, std::string filename)
: config()
, subdir(subdir)
, filename(filename)
{
	auto dir = get_config_base_dir() / path(subdir);
	auto file_path = dir / filename;
	
	if(exists(file_path)) {
		std::ifstream file_stream(file_path.string());
		boost::property_tree::read_json(file_stream, config);
	}
}

Config::~Config()
{
	auto dir = get_config_base_dir() / path(subdir);
	auto file_path = dir / filename;
	
	if(!exists(dir)) {
		boost::filesystem::create_directories(dir);
	}

	std::ofstream file_stream(file_path.string());
	boost::property_tree::write_json(file_stream, config);
}

} //namespace configpp