Logger.hpp

#pragma once
 
#include <functional>
#include <iostream>
#include <string_view>
#include <format>
 
namespace magpie::logger {
 
enum class Level {
    debug,
    info,
    warning,
    error,
    critical
};
 
inline void defaultHandler(Level level, const std::string_view& message) {
    switch (level) {
    case Level::debug:
        printf("DEBUG    %.*s\n", static_cast<int>(message.length()), message.data());
        break;
    case Level::info:
        printf("INFO     %.*s\n", static_cast<int>(message.length()), message.data());
        break;
    case Level::warning:
        printf("WARNING  %.*s\n", static_cast<int>(message.length()), message.data());
        break;
    case Level::error:
        printf("ERROR    %.*s\n", static_cast<int>(message.length()), message.data());
        break;
    case Level::critical:
        printf("CRITICAL %.*s\n", static_cast<int>(message.length()), message.data());
        break;
    }
}
 
struct LoggerConfig {
    std::function<void(logger::Level, const std::string_view&)> logger = logger::defaultHandler;
};
 
inline LoggerConfig& config() {
    static LoggerConfig conf;
    return conf;
}
 
template <Level level, class... Args>
inline void log(const std::format_string<Args...>& fmt, Args&&... args) {
    // TODO: do I add a prefix?
    auto& logger = config().logger;
    if (!logger) {
        return;
    }
    logger(
        level, std::format(fmt, std::forward<Args>(args)...)
    );
}
 
template <class... Args>
inline void debug(const std::format_string<Args...>& format, Args&&... args) {
    log<Level::debug, Args...>(format, std::forward<Args>(args)...);
}
 
template <class... Args>
inline void info(const std::format_string<Args...>& format, Args&&... args) {
    log<Level::info, Args...>(format, std::forward<Args>(args)...);
}
 
template <class... Args>
inline void warn(const std::format_string<Args...>& format, Args&&... args) {
    log<Level::warning, Args...>(format, std::forward<Args>(args)...);
}
 
template <class... Args>
inline void error(const std::format_string<Args...>& format, Args&&... args) {
    log<Level::error, Args...>(format, std::forward<Args>(args)...);
}
 
template <class... Args>
inline void critical(const std::format_string<Args...>& format, Args&&... args) {
    log<Level::critical, Args...>(format, std::forward<Args>(args)...);
}
 
}