#pragma once

#include <iostream>
#include <cstdio>
#include <string>
#include <unistd.h>
#include <filesystem> // C++17
#include <fstream>
#include <memory>
#include <time.h>
#include <sstream>
#include "Mutex.hpp"

namespace LogModule
{
    using namespace LockModule;

    // 获取以下当前系统的时间
    std::string CurrentTime()
    {
        time_t time_stamp = ::time(nullptr);
        struct tm curr;
        // 可重入版本的localtime
        localtime_r(&time_stamp, &curr);

        char buffer[1024];
        snprintf(buffer, sizeof(buffer), "%4d-%02d-%02d %02d:%02d:%02d",
                 curr.tm_year + 1900,
                 curr.tm_mon + 1,
                 curr.tm_mday,
                 curr.tm_hour,
                 curr.tm_min,
                 curr.tm_sec);
        return buffer;
    }

    // 构成:1.构建日志字符串 2.刷新落盘(screen,file)
    // 1. 日志文件的默认路径和文件名
    const std::string defaultlogpath = "./log/";
    const std::string defaultlogname = "log.txt";

    // 2. 日志等级
    enum class LogLevel
    {
        DEBUG = 1,
        INFO,
        WARNING,
        ERROR,
        FATAL
    };

    std::string Level2string(LogLevel level)
    {
        switch (level)
        {
        case LogLevel::DEBUG:
            return "DEBUG";
        case LogLevel::INFO:
            return "INFO";
        case LogLevel::WARNING:
            return "WARNING";
        case LogLevel::ERROR:
            return "ERROR";
        case LogLevel::FATAL:
            return "FATAL";
        default:
            return "None";
        }
    }

    // 3. 刷新策略
    class LogStrategy
    {
    public:
        virtual ~LogStrategy() = default;
        virtual void SyncLog(const std::string &message) = 0;
    };

    // 3.1 控制台策略
    class ConsoleLogStrategy : public LogStrategy
    {
    public:
        ConsoleLogStrategy()
        {
        }
        ~ConsoleLogStrategy()
        {
        }
        void SyncLog(const std::string &message)
        {
            LockGuard lockguard(_lock);
            std::cout << message << std::endl;
        }

    private:
        Mutex _lock;
    };

    // 3.2 文件策略(磁盘)
    class FileLogStrategy : public LogStrategy
    {
    public:
        FileLogStrategy(const std::string &logpath = defaultlogpath, const std::string &logname = defaultlogname)
            : _logpath(logpath), _logname(logname)
        {
            // 确认_logpath是存在的
            // 其实我们可以使用mkdir这个函数来创建，可以用stat函数来判断一个文件是否存在
            LockGuard lockguard(_lock);
            if (std::filesystem::exists(_logpath))
            {
                return;
            }
            try
            {
                std::filesystem::create_directories(_logpath);
            }
            catch (const std::filesystem::filesystem_error &e)
            {
                std::cerr << e.what() << '\n';
            }
        }
        ~FileLogStrategy()
        {
        }
        void SyncLog(const std::string &message)
        {
            LockGuard lockguard(_lock);
            std::string log = _logpath + _logname;
            std::ofstream out(log, std::ios::app); // 日志写入，一定是追加的
            if (!out.is_open())
            {
                return;
            }
            out << message << "\n";

            out.close();
        }

    private:
        std::string _logpath;
        std::string _logname;

        // 锁
        Mutex _lock;
    };

    // 日志类:构建日志字符串,根据策略，进行刷新
    class Logger
    {
    public:
        Logger()
        {
            // 默认采用ConsoleLogStrategy策略
            _strategy = std::make_shared<ConsoleLogStrategy>();
        }
        void EnableConsoleLog()
        {
            _strategy = std::make_shared<ConsoleLogStrategy>();
        }
        void EnableFileLog()
        {
            _strategy = std::make_shared<FileLogStrategy>();
        }

        ~Logger() {}

        // 一条完整的信息: [2025-05-11 12:30:03] [DEBUG] [202938] [main.cc] [16] + 日志的可变部分(<< "hello world" << 3.14 << a << b;)
        class LogMessage
        {
        public:
            LogMessage(LogLevel level, const std::string &filename, int line,Logger &logger)
                : _currtime(CurrentTime())
                , _level(level)
                , _pid(::getpid())
                , _filename(filename)
                , _line(line)
                ,_logger(logger)
            {
                std::stringstream ssbuffer;
                ssbuffer << "[" << _currtime << "] " 
                        << "[" << Level2string(_level) << "] " 
                        << "[" << _pid << "] " 
                        << "[" << _filename << "] "
                        << "[" << _line << "] - ";
                _loginfo = ssbuffer.str();
            }
            template<typename T>
            LogMessage &operator <<(const T &info)
            {
                std::stringstream ss;
                ss << info;
                _loginfo += ss.str();
                return *this;
            }
            ~LogMessage()
            {
                if(_logger._strategy)
                {
                    _logger._strategy->SyncLog(_loginfo);
                }
            }

        private:
            std::string _currtime; // 当前日志时间
            LogLevel _level;       // 日志等级
            pid_t _pid;            // 进程pid
            std::string _filename; // 源文件名称
            int _line;             // 日志所在的行号
            Logger &_logger;       // 负责根据不同的策略进行刷新
            std::string _loginfo;  // 一条完整的日志记录
        };

        // 就是要拷贝 - 临时对象,自动析构,自动刷新
        LogMessage operator()(LogLevel level,const std::string &filename,int line)
        {
            return LogMessage(level,filename,line,*this);
        }

    private:
        std::shared_ptr<LogStrategy> _strategy; // 日志刷新的策略方案
    };

    Logger logger;

    #define LOG(Level) logger(Level,__FILE__,__LINE__)
    #define ENABLE_CONSOLE_LOG() logger.EnableConsoleLog()
    #define ENABLE_FILE_LOG() logger.EnableFileLog()
}