/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <log4cxx/logstring.h>
#include <log4cxx/helpers/loglog.h>
#include <log4cxx/logmanager.h>
#include <log4cxx/helpers/transcoder.h>
#include <iostream>
#if !defined(LOG4CXX)
	#define LOG4CXX 1
#endif
#include <log4cxx/private/log4cxx_private.h>
#include <log4cxx/helpers/aprinitializer.h>
#include <log4cxx/helpers/date.h>
#include <log4cxx/helpers/stringhelper.h>
#include <log4cxx/helpers/systemerrwriter.h>
#include <log4cxx/helpers/optionconverter.h>
#include <mutex>

using namespace LOG4CXX_NS;
using namespace LOG4CXX_NS::helpers;

struct LogLog::LogLogPrivate
{
	LogLogPrivate()
		: startTime{ APRInitializer::getStartTime() }
	{}

	~LogLogPrivate()
	{
		quietMode = true; // Prevent output after deletion by onexit processing chain.
	}

	static LogLog* parent;

	static LogLogPrivate* getInstance()
	{
		if (!parent)
			return nullptr;
		return parent->m_priv.get();
	}

	log4cxx_time_t startTime;

	bool debugEnabled{ false };

	bool timeStampEnabled{ true };

	/**
		   In quietMode not even errors generate any output.
	 */
	bool quietMode{ false };
	std::mutex mutex;
	LogString errorPrefix;
	LogString warnPrefix;
	LogString debugPrefix;
	LogString suffix;
	void setColorEnabled(bool newValue)
	{
		if (newValue)
		{
			this->errorPrefix = LOG4CXX_STR("\x1B[31m"); //red
			this->warnPrefix = LOG4CXX_STR("\x1B[33m"); //yellow
			this->debugPrefix = LOG4CXX_STR("\x1B[32m"); //green
			this->suffix = LOG4CXX_STR("\x1B[0m"); // none
		}
		else
		{
			this->errorPrefix.clear();
			this->warnPrefix.clear();
			this->debugPrefix.clear();
			this->suffix.clear();
		}
	}

	LogString elapsedMicroseconds()
	{
		LogString result;
		if (this->timeStampEnabled)
		{
			auto microsecondInterval = Date::currentTime() - this->startTime;
			StringHelper::toString(microsecondInterval, result);
			result += ' ';
		}
		return result;
	}

	void emit_log(const LogString& prefix, const LogString& msg, const LogString& suffix);

	void emit_log(const LogString& prefix, const LogString& msg, const std::exception& ex, const LogString& suffix);
};

LogLog* LogLog::LogLogPrivate::parent{ nullptr };

LogLog::LogLog() :
	m_priv(std::make_unique<LogLogPrivate>())
{
	LogString log4cxxDebug = OptionConverter::getSystemProperty(LOG4CXX_STR("LOG4CXX_DEBUG"), LOG4CXX_STR("false"));
	m_priv->debugEnabled = OptionConverter::toBoolean(log4cxxDebug, false);
	auto logLogTimestamps = OptionConverter::getSystemProperty(LOG4CXX_STR("LOG4CXX_DEBUG_TIMESTAMPS"), LOG4CXX_STR("true"));
	m_priv->timeStampEnabled = OptionConverter::toBoolean(logLogTimestamps, true);
	auto color = OptionConverter::getSystemProperty(LOG4CXX_STR("LOG4CXX_COLOR"), LOG4CXX_STR("true"));
	m_priv->setColorEnabled(OptionConverter::toBoolean(color, true));
}

LogLog::~LogLog()
{
	LogLogPrivate::parent = nullptr;
}

ObjectPtr LogLog::_createInstance()
{
	using LogLogHolder = SingletonHolder<LogLog>;
	auto pLogLog = std::make_shared<LogLogHolder>();
	LogLogPrivate::parent = &pLogLog->value();
	debug(LOG4CXX_STR("Started"));
	return pLogLog;
}

bool LogLog::isDebugEnabled()
{
	auto p = LogLogPrivate::getInstance();
	return p && !p->quietMode // Not deleted by onexit processing?
			 && p->debugEnabled;
}

bool LogLog::isDebugEnabledFor(const LoggerPtr& category)
{
	return isDebugEnabled() && category && category->isDebugEnabled();
}

bool LogLog::isTraceEnabledFor(const LoggerPtr& category)
{
	return isDebugEnabled() && category && category->isTraceEnabled();
}

void LogLog::setInternalDebugging(bool debugEnabled1)
{
	auto p = LogLogPrivate::getInstance();
	if (p && !p->quietMode) // Not deleted by onexit processing?
		p->debugEnabled = debugEnabled1;
}

bool LogLog::isColorEnabled()
{
	auto p = LogLogPrivate::getInstance();
	return p && !p->errorPrefix.empty();
}

void LogLog::setColorEnabled(bool newValue)
{
	if (auto p = LogLogPrivate::getInstance())
		p->setColorEnabled(newValue);
}

void LogLog::debug(const LogString& msg)
{
	auto p = LogLogPrivate::getInstance();
	if (p && !p->quietMode) // Not deleted by onexit processing?
	{
		if (!p->debugEnabled)
		{
			return;
		}

		std::lock_guard<std::mutex> lock(p->mutex);
		p->emit_log(p->debugPrefix, msg, p->suffix);
	}
}

void LogLog::debug(const LogString& msg, const std::exception& e)
{
	auto p = LogLogPrivate::getInstance();
	if (p && !p->quietMode) // Not deleted by onexit processing?
	{
		if (!p->debugEnabled)
			return;

		std::lock_guard<std::mutex> lock(p->mutex);
		p->emit_log(p->debugPrefix, msg, e, p->suffix);
	}
}


void LogLog::error(const LogString& msg)
{
	auto p = LogLogPrivate::getInstance();
	if (p && !p->quietMode) // Not deleted by onexit processing?
	{
		std::lock_guard<std::mutex> lock(p->mutex);

		p->emit_log(p->errorPrefix, msg, p->suffix);
	}
}

void LogLog::error(const LogString& msg, const std::exception& e)
{
	auto p = LogLogPrivate::getInstance();
	if (p && !p->quietMode) // Not deleted by onexit processing?
	{
		std::lock_guard<std::mutex> lock(p->mutex);
		p->emit_log(p->errorPrefix, msg, e, p->suffix);
	}
}

LoggerPtr LogLog::getLogger(const LogString& name)
{
	return LogManager::getLoggerRepository()->getLogger(name);
}

#if !LOG4CXX_LOGCHAR_IS_UTF8
void LogLog::trace(const LoggerPtr& category, const std::string& msg)
{
	LOG4CXX_DECODE_CHAR(lsMsg, msg);
	trace(category, lsMsg);
}
#endif

void LogLog::trace(const LoggerPtr& category, const LogString& msg)
{
	auto p = LogLogPrivate::getInstance();
	if (p && !p->quietMode) // Not deleted by onexit processing?
	{
		if (!p->debugEnabled)
		{
			return;
		}

		std::lock_guard<std::mutex> lock(p->mutex);
		p->emit_log(p->debugPrefix, category->getName() + LOG4CXX_STR("::") + msg, p->suffix);
	}
}

void LogLog::setQuietMode(bool quietMode1)
{
	auto p = LogLogPrivate::getInstance();
	std::lock_guard<std::mutex> lock(p->mutex);

	p->quietMode = quietMode1;
}

void LogLog::warn(const LogString& msg)
{
	auto p = LogLogPrivate::getInstance();
	if (p && !p->quietMode) // Not deleted by onexit processing?
	{
		std::lock_guard<std::mutex> lock(p->mutex);
		p->emit_log(p->warnPrefix, msg, p->suffix);
	}
}

void LogLog::warn(const LogString& msg, const std::exception& e)
{
	auto p = LogLogPrivate::getInstance();
	if (p && !p->quietMode) // Not deleted by onexit processing?
	{
		std::lock_guard<std::mutex> lock(p->mutex);
		p->emit_log(p->warnPrefix, msg, e, p->suffix);
	}
}

void LogLog::LogLogPrivate::emit_log(const LogString& prefix, const LogString& msg, const LogString& suffix)
{
	LogString out(elapsedMicroseconds() + LOG4CXX_STR("log4cxx: "));
	out.append(prefix);
	out.append(msg);
	out.append(suffix);
	out.append(1, (logchar) 0x0A);

	SystemErrWriter().write(out);
}

void LogLog::LogLogPrivate::emit_log(const LogString& prefix, const LogString& msg, const std::exception& ex, const LogString& suffix)
{
	LogString out(elapsedMicroseconds() + LOG4CXX_STR("log4cxx: "));
	out.append(prefix);
	LogString exOut;
	if (auto raw = ex.what())
	{
		exOut.append(out);
		Transcoder::decode(raw, exOut);
	}
	out.append(suffix);
	out.append(1, (logchar) 0x0A);

	SystemErrWriter errWriter;
	errWriter.write(out);
	if (!exOut.empty())
	{
		exOut.append(suffix);
		exOut.append(1, (logchar) 0x0A);
		errWriter.write(exOut);
	}
}