///////////////////////////////////////////////////////////////////////////////
// LameXP - Audio Encoder Front-End
// Copyright (C) 2004-2013 LoRd_MuldeR <MuldeR2@GMX.de>
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version, but always including the *additional*
// restrictions defined in the "License.txt" file.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License along
// with this program; if not, write to the Free Software Foundation, Inc.,
// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
//
// http://www.gnu.org/licenses/gpl-2.0.txt
///////////////////////////////////////////////////////////////////////////////

#include "Thread_CheckUpdate.h"

#include "Global.h"

#include <QStringList>
#include <QFile>
#include <QFileInfo>
#include <QProcess>
#include <QUrl>
#include <QEventLoop>
#include <QTimer>

///////////////////////////////////////////////////////////////////////////////
// CONSTANTS
///////////////////////////////////////////////////////////////////////////////

static const char *header_id = "!Update";
static const char *section_id = "LameXP";

static const char *mirror_url_postfix[] = 
{
	"update.ver",
	"update_beta.ver",
	NULL
};

static const char *update_mirrors_prim[] =
{
	"http://muldersoft.com/",
	"http://mulder.bplaced.net/",
	"http://mulder.cwsurf.de/",
	"http://mulder.6te.net/",
	"http://mulder.webuda.com/",
	"http://mulder.byethost13.com/",
	"http://muldersoft.kilu.de/",
	"http://muldersoft.zxq.net/",
	"http://lamexp.sourceforge.net/",
	"http://lamexp.berlios.de/",
	"http://lordmulder.github.com/LameXP/",
	"http://lord_mulder.bitbucket.org/",
	"http://www.tricksoft.de/",
	NULL
};

static const char *update_mirrors_back[] =
{
	"http://mplayer.savedonthe.net/",
	NULL
};

static const char *known_hosts[] =		//Taken form: http://www.alexa.com/topsites !!!
{
	"http://www.163.com/",
	"http://www.ac3filter.net/",
	"http://www.amazon.com/",
	"http://www.aol.com/",
	"http://www.apache.org/",
	"http://www.apple.com/",
	"http://www.adobe.com/",
	"http://www.avidemux.org/",
	"http://www.babylon.com/",
	"http://www.baidu.com/",
	"http://www.bbc.co.uk/",
	"http://www.berlios.de/",
	"http://www.bing.com/",
	"http://www.cnet.com/",
	"http://cnzz.com/",
	"http://codecs.com/",
	"http://www.codeplex.com/",
	"http://qt.digia.com/",
	"http://www.ebay.com/",
	"http://www.equation.com/",
	"http://fc2.com/",
	"http://www.ffmpeg.org/",
	"http://www.flickr.com/",
	"http://blog.gitorious.org/",
	"http://git-scm.com/",
	"http://www.gnome.org/",
	"http://www.gnu.org/",
	"http://go.com/",
	"http://code.google.com/",
	"http://www.heise.de/",
	"http://www.huffingtonpost.co.uk/",
	"http://www.iana.org/",
	"http://www.imdb.com/",
	"http://www.imgburn.com/",
	"http://imgur.com/",
	"http://en.jd.com/",
	"http://mirrors.kernel.org/",
	"http://www.libav.org/",
	"http://www.linkedin.com/about-us",
	"http://www.livedoor.com/",
	"http://www.livejournal.com/",
	"http://mail.ru/",
	"http://www.mediafire.com/",
	"http://www.mozilla.org/en-US/",
	"http://mplayerhq.hu/",
	"http://www.msn.com/?st=1",
	"http://oss.netfarm.it/",
	"http://www.nytimes.com/",
	"http://www.opera.com/",
	"http://www.portablefreeware.com/",
	"http://qt-project.org/",
	"http://www.quakelive.com/",
	"http://www.seamonkey-project.org/",
	"http://www.sina.com.cn/",
	"http://www.sohu.com/",
	"http://www.soso.com/",
	"http://sourceforge.net/",
	"http://www.spiegel.de/",
	"http://tdm-gcc.tdragon.net/",
	"http://www.tdrsmusic.com/",
	"http://www.ubuntu.com/",
	"http://status.twitter.com/",
	"http://www.uol.com.br/",
	"http://www.videohelp.com/",
	"http://www.videolan.org/",
	"http://www.weibo.com/",
	"http://www.wikipedia.org/",
	"http://www.winamp.com/",
	"http://wordpress.com/",
	"http://us.yahoo.com/",
	"http://www.yandex.ru/",
	"http://www.youtube.com/",
	"http://www.zedo.com/",
	"http://ffmpeg.zeranoe.com/",
	NULL
};

static const int MIN_CONNSCORE = 8;
static const int VERSION_INFO_EXPIRES_MONTHS = 6;
static char *USER_AGENT_STR = "Mozilla/5.0 (X11; Linux i686; rv:7.0.1) Gecko/20111106 IceCat/7.0.1";

//Helper function
static int getMaxProgress(void)
{
	int counter = MIN_CONNSCORE + 2;
	for(int i = 0; update_mirrors_prim[i]; i++) counter++;
	for(int i = 0; update_mirrors_back[i]; i++) counter++;
	return counter;
}

////////////////////////////////////////////////////////////
// Update Info Class
////////////////////////////////////////////////////////////

UpdateInfo::UpdateInfo(void)
{
	resetInfo();
}
	
void UpdateInfo::resetInfo(void)
{
	m_buildNo = 0;
	m_buildDate.setDate(1900, 1, 1);
	m_downloadSite.clear();
	m_downloadAddress.clear();
	m_downloadFilename.clear();
	m_downloadFilecode.clear();
}

////////////////////////////////////////////////////////////
// Constructor & Destructor
////////////////////////////////////////////////////////////

UpdateCheckThread::UpdateCheckThread(const bool betaUpdates, const bool testMode)
:
	m_updateInfo(new UpdateInfo()),
	m_betaUpdates(betaUpdates),
	m_testMode(testMode),
	m_binaryWGet(lamexp_lookup_tool("wget.exe")),
	m_binaryGnuPG(lamexp_lookup_tool("gpgv.exe")),
	m_binaryKeys(lamexp_lookup_tool("gpgv.gpg")),
	m_maxProgress(getMaxProgress())
{
	m_success = false;
	m_status = UpdateStatus_NotStartedYet;
	m_progress = 0;

	if(m_binaryWGet.isEmpty() || m_binaryGnuPG.isEmpty() || m_binaryKeys.isEmpty())
	{
		THROW("Tools not initialized correctly!");
	}
}

UpdateCheckThread::~UpdateCheckThread(void)
{
	delete m_updateInfo;
}

////////////////////////////////////////////////////////////
// Protected functions
////////////////////////////////////////////////////////////

void UpdateCheckThread::run(void)
{
	qDebug("Update checker thread started!");

	try
	{
		m_testMode ? testKnownHosts() : checkForUpdates();
	}
	catch(const std::exception &error)
	{
		fflush(stdout); fflush(stderr);
		fprintf(stderr, "\nGURU MEDITATION !!!\n\nException error:\n%s\n", error.what());
		lamexp_fatal_exit(L"Unhandeled C++ exception error, application will exit!");
	}
	catch(...)
	{
		fflush(stdout); fflush(stderr);
		fprintf(stderr, "\nGURU MEDITATION !!!\n\nUnknown exception error!\n");
		lamexp_fatal_exit(L"Unhandeled C++ exception error, application will exit!");
	}

	qDebug("Update checker thread completed.");
}

void UpdateCheckThread::checkForUpdates(void)
{
	// ----- Initialization ----- //

	m_success = false;
	m_updateInfo->resetInfo();
	setProgress(0);

	// ----- Test Internet Connection ----- //

	int connectionScore = 0;
	
	log("Checking internet connection...");
	setStatus(UpdateStatus_CheckingConnection);

	const int networkStatus = lamexp_network_status();
	if(networkStatus == lamexp_network_non)
	{
		log("", "Operating system reports that the computer is currently offline !!!");
		setProgress(m_maxProgress);
		setStatus(UpdateStatus_ErrorNoConnection);
		return;
	}
	
	setProgress(1);

	// ----- Test Known Hosts Connectivity ----- //

	QStringList hostList;
	for(int i = 0; known_hosts[i]; i++)
	{
		hostList << QString::fromLatin1(known_hosts[i]);
	}

	lamexp_seed_rand();
	while(!hostList.isEmpty())
	{
		QString currentHost = hostList.takeAt(lamexp_rand() % hostList.count());
		if(connectionScore < MIN_CONNSCORE)
		{
			log("", "Testing host:", currentHost);
			QString outFile = QString("%1/%2.htm").arg(lamexp_temp_folder2(), lamexp_rand_str());
			bool httpOk = false;
			if(getFile(currentHost, outFile, 0, &httpOk))
			{
				connectionScore++;
				setProgress(qBound(1, connectionScore + 1, MIN_CONNSCORE + 1));
				lamexp_sleep(64);
			}
			if(httpOk)
			{
				connectionScore++;
				setProgress(qBound(1, connectionScore + 1, MIN_CONNSCORE + 1));
				lamexp_sleep(64);
			}
			QFile::remove(outFile);
		}
	}

	if(connectionScore < MIN_CONNSCORE)
	{
		setProgress(m_maxProgress);
		setStatus(UpdateStatus_ErrorConnectionTestFailed);
		return;
	}

	// ----- Build Mirror List ----- //

	log("", "----", "", "Checking for updates online...");
	setStatus(UpdateStatus_FetchingUpdates);

	QStringList mirrorList;
	for(int index = 0; update_mirrors_prim[index]; index++)
	{
		mirrorList << QString::fromLatin1(update_mirrors_prim[index]);
	}

	lamexp_seed_rand();
	if(const int len = mirrorList.count())
	{
		const int rounds = len * 1097;
		for(int i = 0; i < rounds; i++)
		{
			mirrorList.swap(i % len, lamexp_rand() % len);
		}
	}

	for(int index = 0; update_mirrors_back[index]; index++)
	{
		mirrorList << QString::fromLatin1(update_mirrors_back[index]);
	}
	
	// ----- Fetch Update Info From Server ----- //

	while(!mirrorList.isEmpty())
	{
		QString currentMirror = mirrorList.takeFirst();
		setProgress(m_progress + 1);
		if(!m_success)
		{
			if(tryUpdateMirror(m_updateInfo, currentMirror))
			{
				m_success = true;
			}
		}
		else
		{
			lamexp_sleep(64);
		}
	}
	
	setProgress(m_maxProgress);

	if(m_success)
	{
		if(m_updateInfo->m_buildNo > lamexp_version_build())
		{
			setStatus(UpdateStatus_CompletedUpdateAvailable);
		}
		else if(m_updateInfo->m_buildNo == lamexp_version_build())
		{
			setStatus(UpdateStatus_CompletedNoUpdates);
		}
		else
		{
			setStatus(UpdateStatus_CompletedNewVersionOlder);
		}
	}
	else
	{
		setStatus(UpdateStatus_ErrorFetchUpdateInfo);
	}
}

void UpdateCheckThread::testKnownHosts(void)
{
	QStringList hostList;
	for(int i = 0; known_hosts[i]; i++)
	{
		hostList << QString::fromLatin1(known_hosts[i]);
	}

	qDebug("\n[Known Hosts]");
	log("Testing all known hosts...", "", "---");

	int hostCount = hostList.count();
	while(!hostList.isEmpty())
	{
		QString currentHost = hostList.takeFirst();
		qDebug("Testing: %s", currentHost.toLatin1().constData());
		log("", "Testing:", currentHost, "");
		QString outFile = QString("%1/%2.htm").arg(lamexp_temp_folder2(), lamexp_rand_str());
		bool httpOk = false;
		if(!getFile(currentHost, outFile, 0, &httpOk))
		{
			if(httpOk)
			{
				qWarning("\nConnectivity test was SLOW on the following site:\n%s\n", currentHost.toLatin1().constData());
			}
			else
			{
				qWarning("\nConnectivity test FAILED on the following site:\n%s\n", currentHost.toLatin1().constData());
			}
		}
		log("", "---");
		QFile::remove(outFile);
	}
}

////////////////////////////////////////////////////////////
// PRIVATE FUNCTIONS
////////////////////////////////////////////////////////////

void UpdateCheckThread::setStatus(const int status)
{
	if(m_status != status)
	{
		m_status = status;
		emit statusChanged(status);
	}
}

void UpdateCheckThread::setProgress(const int progress)
{
	if(m_progress != progress)
	{
		m_progress = progress;
		emit progressChanged(progress);
	}
}

void UpdateCheckThread::log(const QString &str1, const QString &str2, const QString &str3, const QString &str4)
{
	if(!str1.isNull()) emit messageLogged(str1);
	if(!str2.isNull()) emit messageLogged(str2);
	if(!str3.isNull()) emit messageLogged(str3);
	if(!str4.isNull()) emit messageLogged(str4);
}

bool UpdateCheckThread::tryUpdateMirror(UpdateInfo *updateInfo, const QString &url)
{
	bool success = false;
	log("", "Trying mirror:", url);

	QString randPart = lamexp_rand_str();
	QString outFileVersionInfo = QString("%1/%2.ver").arg(lamexp_temp_folder2(), randPart);
	QString outFileSignature = QString("%1/%2.sig").arg(lamexp_temp_folder2(), randPart);

	log("", "Downloading update info:");
	bool ok1 = getFile(QString("%1%2").arg(url, mirror_url_postfix[m_betaUpdates ? 1 : 0]), outFileVersionInfo);

	log("", "Downloading signature:");
	bool ok2 = getFile(QString("%1%2.sig").arg(url, mirror_url_postfix[m_betaUpdates ? 1 : 0]), outFileSignature);

	if(ok1 && ok2)
	{
		log("", "Download okay, checking signature:");
		if(checkSignature(outFileVersionInfo, outFileSignature))
		{
			log("", "Signature okay, parsing info:");
			success = parseVersionInfo(outFileVersionInfo, updateInfo);
		}
		else
		{
			log("", "Bad signature, take care!");
		}
	}
	else
	{
		log("", "Download has failed!");
	}

	QFile::remove(outFileVersionInfo);
	QFile::remove(outFileSignature);
	
	return success;
}

bool UpdateCheckThread::getFile(const QString &url, const QString &outFile, unsigned int maxRedir, bool *httpOk)
{
	QFileInfo output(outFile);
	output.setCaching(false);
	if(httpOk) *httpOk = false;

	if(output.exists())
	{
		QFile::remove(output.canonicalFilePath());
		if(output.exists())
		{
			return false;
		}
	}

	QProcess process;
	lamexp_init_process(process, output.absolutePath());

	QStringList args;
	args << "--no-cache" << "--no-dns-cache" << QString().sprintf("--max-redirect=%u", maxRedir);
	args << QString("--referer=%1://%2/").arg(QUrl(url).scheme(), QUrl(url).host()) << "-U" << USER_AGENT_STR;
	args << "-O" << output.fileName() << url;

	QEventLoop loop;
	connect(&process, SIGNAL(error(QProcess::ProcessError)), &loop, SLOT(quit()));
	connect(&process, SIGNAL(finished(int,QProcess::ExitStatus)), &loop, SLOT(quit()));
	connect(&process, SIGNAL(readyRead()), &loop, SLOT(quit()));

	QTimer timer;
	timer.setSingleShot(true);
	timer.setInterval(25000);
	connect(&timer, SIGNAL(timeout()), &loop, SLOT(quit()));

	const QRegExp httpResponseOK("200 OK$");
	
	process.start(m_binaryWGet, args);
	
	if(!process.waitForStarted())
	{
		return false;
	}

	timer.start();

	while(process.state() == QProcess::Running)
	{
		loop.exec();
		bool bTimeOut = (!timer.isActive());
		while(process.canReadLine())
		{
			QString line = QString::fromLatin1(process.readLine()).simplified();
			if(line.contains(httpResponseOK))
			{
				line.append(" [OK]");
				if(httpOk) *httpOk = true;
			}
			log(line);
		}
		if(bTimeOut)
		{
			qWarning("WGet process timed out <-- killing!");
			process.kill();
			process.waitForFinished();
			log("!!! TIMEOUT !!!");
			return false;
		}
	}
	
	timer.stop();
	timer.disconnect(&timer, SIGNAL(timeout()), &loop, SLOT(quit()));

	log(QString().sprintf("Exited with code %d", process.exitCode()));
	return (process.exitCode() == 0) && output.exists() && output.isFile();
}

bool UpdateCheckThread::checkSignature(const QString &file, const QString &signature)
{
	if(QFileInfo(file).absolutePath().compare(QFileInfo(signature).absolutePath(), Qt::CaseInsensitive) != 0)
	{
		qWarning("CheckSignature: File and signature should be in same folder!");
		return false;
	}
	if(QFileInfo(file).absolutePath().compare(QFileInfo(m_binaryKeys).absolutePath(), Qt::CaseInsensitive) != 0)
	{
		qWarning("CheckSignature: File and keyring should be in same folder!");
		return false;
	}

	QProcess process;
	lamexp_init_process(process, QFileInfo(file).absolutePath());

	QEventLoop loop;
	connect(&process, SIGNAL(error(QProcess::ProcessError)), &loop, SLOT(quit()));
	connect(&process, SIGNAL(finished(int,QProcess::ExitStatus)), &loop, SLOT(quit()));
	connect(&process, SIGNAL(readyRead()), &loop, SLOT(quit()));
	
	process.start(m_binaryGnuPG, QStringList() << "--homedir" << "." << "--keyring" << QFileInfo(m_binaryKeys).fileName() << QFileInfo(signature).fileName() << QFileInfo(file).fileName());

	if(!process.waitForStarted())
	{
		return false;
	}

	while(process.state() == QProcess::Running)
	{
		loop.exec();
		while(process.canReadLine())
		{
			log(QString::fromLatin1(process.readLine()).simplified());
		}
	}
	
	log(QString().sprintf("Exited with code %d", process.exitCode()));
	return (process.exitCode() == 0);
}

bool UpdateCheckThread::parseVersionInfo(const QString &file, UpdateInfo *updateInfo)
{
	QRegExp value("^(\\w+)=(.+)$");
	QRegExp section("^\\[(.+)\\]$");

	QDate updateInfoDate;
	updateInfo->resetInfo();

	QFile data(file);
	if(!data.open(QIODevice::ReadOnly))
	{
		qWarning("Cannot open update info file for reading!");
		return false;
	}
	
	bool inHeader = false;
	bool inSection = false;
	
	while(!data.atEnd())
	{
		QString line = QString::fromLatin1(data.readLine()).trimmed();
		if(section.indexIn(line) >= 0)
		{
			log(QString("Sec: [%1]").arg(section.cap(1)));
			inSection = (section.cap(1).compare(section_id, Qt::CaseInsensitive) == 0);
			inHeader = (section.cap(1).compare(header_id, Qt::CaseInsensitive) == 0);
			continue;
		}
		if(inSection && (value.indexIn(line) >= 0))
		{
			log(QString("Val: '%1' ==> '%2").arg(value.cap(1), value.cap(2)));
			if(value.cap(1).compare("BuildNo", Qt::CaseInsensitive) == 0)
			{
				bool ok = false;
				unsigned int temp = value.cap(2).toUInt(&ok);
				if(ok) updateInfo->m_buildNo = temp;
			}
			else if(value.cap(1).compare("BuildDate", Qt::CaseInsensitive) == 0)
			{
				QDate temp = QDate::fromString(value.cap(2).trimmed(), Qt::ISODate);
				if(temp.isValid()) updateInfo->m_buildDate = temp;
			}
			else if(value.cap(1).compare("DownloadSite", Qt::CaseInsensitive) == 0)
			{
				updateInfo->m_downloadSite = value.cap(2).trimmed();
			}
			else if(value.cap(1).compare("DownloadAddress", Qt::CaseInsensitive) == 0)
			{
				updateInfo->m_downloadAddress = value.cap(2).trimmed();
			}
			else if(value.cap(1).compare("DownloadFilename", Qt::CaseInsensitive) == 0)
			{
				updateInfo->m_downloadFilename = value.cap(2).trimmed();
			}
			else if(value.cap(1).compare("DownloadFilecode", Qt::CaseInsensitive) == 0)
			{
				updateInfo->m_downloadFilecode = value.cap(2).trimmed();
			}
		}
		if(inHeader && (value.indexIn(line) >= 0))
		{
			log(QString("Val: '%1' ==> '%2").arg(value.cap(1), value.cap(2)));
			if(value.cap(1).compare("TimestampCreated", Qt::CaseInsensitive) == 0)
			{
				QDate temp = QDate::fromString(value.cap(2).trimmed(), Qt::ISODate);
				if(temp.isValid()) updateInfoDate = temp;
			}
		}
	}
	
	if(!updateInfoDate.isValid())
	{
		updateInfo->resetInfo();
		log("WARNING: Version info timestamp is missing!");
		return false;
	}
	else if(updateInfoDate.addMonths(VERSION_INFO_EXPIRES_MONTHS) < lamexp_current_date_safe())
	{
		updateInfo->resetInfo();
		log(QString::fromLatin1("WARNING: This version info has expired at %1!").arg(updateInfoDate.addMonths(VERSION_INFO_EXPIRES_MONTHS).toString(Qt::ISODate)));
		return false;
	}
	else if(lamexp_current_date_safe() < updateInfoDate)
	{
		log("Version info is from the future, take care!");
		qWarning("Version info is from the future, take care!");
	}

	bool complete = true;

	if(!(updateInfo->m_buildNo > 0)) complete = false;
	if(!(updateInfo->m_buildDate.year() >= 2010)) complete = false;
	if(updateInfo->m_downloadSite.isEmpty()) complete = false;
	if(updateInfo->m_downloadAddress.isEmpty()) complete = false;
	if(updateInfo->m_downloadFilename.isEmpty()) complete = false;
	if(updateInfo->m_downloadFilecode.isEmpty()) complete = false;
	
	if(!complete)
	{
		log("WARNING: Version info is incomplete!");
	}

	return complete;
}

////////////////////////////////////////////////////////////
// SLOTS
////////////////////////////////////////////////////////////

/*NONE*/

////////////////////////////////////////////////////////////
// EVENTS
////////////////////////////////////////////////////////////

/*NONE*/