#pragma once

#ifndef TLOGGER_INCLUDED

#define TLOGGER_INCLUDED

#include <memory></memory>

//

// TLogger

//

// usage example:

//

//    TFilePath fp;

//    TLogger::info() << "Loading " << fp << " ...";

//    TLogger::error() << "File " << fp << "not found";

//

// N.B.

//    TLogger::debug() << ....

//    is automatically removed in the release

//

#include "tcommon.h"

#undef DVAPI

#undef DVVAR

#ifdef TSYSTEM_EXPORTS

#define DVAPI DV_EXPORT_API

#define DVVAR DV_EXPORT_VAR

#else

#define DVAPI DV_IMPORT_API

#define DVVAR DV_IMPORT_VAR

#endif

class TFilePath;

class DVAPI TLogger

{ // singleton

	class Imp;

	std::unique_ptr<imp> m_imp;</imp>

	TLogger();

public:

	~TLogger();

	static TLogger *instance();

	enum MessageType {

		Debug = 1,

		Info,

		Warning,

		Error

	};

	class DVAPI Message

	{

		MessageType m_type;

		std::string m_timestamp;

		std::string m_text;

	public:

		Message(MessageType type, std::string text);

		MessageType getType() const { return m_type; }

		std::string getTimestamp() const { return m_timestamp; }

		std::string getText() const { return m_text; }

	};

	class Listener

	{

	public:

		virtual void onLogChanged() = 0;

		virtual ~Listener() {}

	};

	void addMessage(const Message &msg);

	void clearMessages();

	int getMessageCount() const;

	Message getMessage(int index) const;

	void addListener(Listener *listener);

	void removeListener(Listener *listener);

	class DVAPI Stream

	{

		MessageType m_type;

		std::string m_text;

	public:

		Stream(MessageType type);

		~Stream();

		Stream &operator<<(std::string v);

		Stream &operator<<(int v);

		Stream &operator<<(double v);

		Stream &operator<<(const TFilePath &v);

	};

	class DVAPI NullStream

	{

	public:

		NullStream() {}

		~NullStream() {}

		NullStream &operator<<(std::string) { return *this; }

		NullStream &operator<<(int) { return *this; }

		NullStream &operator<<(double) { return *this; }

		NullStream &operator<<(const TFilePath &) { return *this; }

	};

#ifdef NDEBUG

	static NullStream debug()

	{

		return NullStream();

	}

#else

	static Stream debug()

	{

		return Stream(Debug);

	}

#endif

	static Stream info()

	{

		return Stream(Info);

	}

	static Stream warning() { return Stream(Warning); }

	static Stream error() { return Stream(Error); }

};

#endif