NBEngine/include/Errors.hpp
2025-11-06 02:03:49 -06:00

91 lines
2.6 KiB
C++

#pragma once
#ifndef _NB_ERROR
#define _NB_ERROR
#include <exception>
#include <string.h>
#include <string>
#include <type_traits>
#include <unordered_map>
namespace nb {
typedef std::unordered_map<unsigned int, const char*> ErrorCodeMap;
template<class ErrorType>
class ErrorBase : public std::exception {
public:
static std::string lookup(unsigned int);
virtual const char* what() const noexcept override final {
return static_cast<const ErrorType*>(this)->_msg.c_str();
};
unsigned int code() const noexcept {
return static_cast<const ErrorType*>(this)->_code;
};
protected:
ErrorBase() = default;
ErrorBase(
const unsigned int code,
std::string msg,
std::exception* const trace,
unsigned int line=0,
std::string filename=""
) noexcept : _code{code} {
static_assert(std::is_same<const std::unordered_map<unsigned int, const char*>, decltype(ErrorType::ErrorMessages)>::value,
"const std::unordered_map<unsigned int, const char*> ErrorMessages must be "
"a class member."
);
static_assert(std::is_enum_v<typename ErrorType::ErrorCodes>, "enum ErrorCodes must be a class member.");
static_assert(std::is_same<std::underlying_type_t<typename ErrorType::ErrorCodes>, unsigned int>::value,
"enum ErrorCodes must be of underlying type unsigned int."
);
static_assert(std::is_same<const std::string, decltype(ErrorType::type)>::value,
"const std::string type must be a class member."
);
_msg = std::string(ErrorType::type);
_msg += ":" + std::to_string(code);
if (line && filename.size()) {
_msg += " in \'" + filename + "\':" + std::to_string(line);
}
_msg += "\n\t" + msg;
if (trace) {
_msg += "\nTraceback - " + std::string(trace->what());
}
}
const unsigned int _code;
std::string _msg;
};
class Error : public ErrorBase<Error> {
public:
Error(unsigned int code, std::exception* const trace=nullptr)
: ErrorBase<Error>(code, ErrorBase<Error>::lookup(code), trace) {}
enum ErrorCodes : unsigned int {
UNDEFINED, BADERRORCODE
};
static const std::string type;
static const ErrorCodeMap ErrorMessages;
};
template<class ErrorType>
std::string ErrorBase<ErrorType>::lookup(unsigned int code) {
for (auto kv : ErrorType::ErrorMessages) {
if (kv.first==code) {
return std::string(kv.second);
}
}
throw Error(Error::ErrorCodes::BADERRORCODE);
}
} // namespace nb
#endif // _NB_ERROR