// SystemError.cpp

//#include <cipres_config.h>

#if defined(_WIN32) || defined(_WIN64)

#define WIN32_LEAN_AND_MEAN

#include <windows.h>

#endif

#include <new>
#include <cstring>
#include <boost/shared_array.hpp>
#include "SystemError.hpp"


#define MAX_MESSAGE_LENGTH  1024


namespace CipresJNI {


// SystemError

// constructor
SystemError::SystemError(const char *who, const char *message, int code) throw() : std::runtime_error(message), m_error_code(code)
{
	try {
#if defined(_WIN32) || defined(_WIN64)

		int wide_length;
		boost::shared_array<char> system_message;
		boost::shared_array<wchar_t> wide_message(new wchar_t[MAX_MESSAGE_LENGTH]);

		if((wide_length = ::FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, NULL, code, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), wide_message.get(), MAX_MESSAGE_LENGTH, NULL)) != 0) {
			int multi_byte_length = ::WideCharToMultiByte(CP_UTF8, 0, wide_message.get(), wide_length, NULL, 0, NULL, NULL);

			if(multi_byte_length == 0)
				return;

			system_message.reset(new char[multi_byte_length]);

			::WideCharToMultiByte(CP_UTF8, 0, wide_message.get(), wide_length, system_message.get(), multi_byte_length, NULL, NULL);
		}
		else {
			system_message.reset(new char[14]);

			std::memcpy(system_message.get(), "Unknown error", 14);
		}

#elif defined(__unix) || defined(__unix__) || (defined(__APPLE__) && defined(__MACH__))

		boost::shared_array<char> system_message(new char[MAX_MESSAGE_LENGTH]);

		::strerror_r(code, system_message.get(), MAX_MESSAGE_LENGTH);

#endif

		if(who != NULL) {
			m_error_message.append(who);
 			m_error_message.append(": ");

			if(message != NULL) {
				m_error_message.append(message);
				m_error_message.append(": ");
			}
		}
		else if(message != NULL) {
			m_error_message.append(message);
			m_error_message.append(": ");
		}

		m_error_message.append(system_message.get());
	}
	catch(...) {
		// we're presumably already handling an error, and it's unlikely that an exception
		//  thrown from within the handler will be caught correctly, so we swallow it and
		//  rely on std::runtime_error to provide a message
	}
}


} // namespace CipresJNI