#ifndef LOGGER_H
#define LOGGER_H

#include "common.h"
#include <string>
#include <fstream>
#include <mutex>
#include <vector>

class Logger {
public:
    enum LogLevel {
        DEBUG,
        INFO,
        WARN,
        ERROR
    };

    static Logger& GetInstance();

    // Initialize logger
    bool Initialize(const std::string& log_file,
                   LogLevel level = INFO,
                   size_t max_size_mb = 100);

    // Log methods
    void LogDNSQuery(const std::string& domain,
                    const std::string& client_ip,
                    FilterAction action);

    void LogInfo(const std::string& message);
    void LogError(const std::string& message);
    void LogDebug(const std::string& message);
    void LogWarn(const std::string& message);

    // Flush buffered logs
    void Flush();

    // Close logger
    void Close();

private:
    Logger() = default;
    ~Logger();

    // Prevent copying
    Logger(const Logger&) = delete;
    Logger& operator=(const Logger&) = delete;

    std::ofstream log_file_;
    std::string log_path_;
    LogLevel current_level_;
    size_t max_size_bytes_;
    std::atomic<size_t> current_size_;

    // Thread safety
    std::mutex log_mutex_;

    // Buffering
    std::vector<std::string> buffer_;
    size_t buffer_threshold_ = 100;

    bool initialized_ = false;

    // Helper functions
    void WriteLog(LogLevel level, const std::string& message);
    void RotateLogFile();
    std::string GetTimestamp() const;
    std::string LogLevelToString(LogLevel level) const;
};

#endif // LOGGER_H