#include <myx/base/config.hpp>
#include <myx/filesystem/current_executable.hpp>
#include <myx/filesystem/paths.hpp>

#include <paths.h>

#include <QCoreApplication>
#include <QString>

namespace myx {

namespace filesystem {

Paths::Paths() = default;

Paths::HierarchyType Paths::getHierarchyType()
{
	QRegExp binRegexp( "/s*bin$" );
	auto binaryDir = m_currentExecutable.m_canonicalFilePath.canonicalPath();

	if ( binRegexp.indexIn( binaryDir ) == -1 )
	{
		return ( HierarchyType::kFlat );
	}

	QRegExp optRegexp( "^/opt(/|/.+/)" + m_projectName + "/" );

	if ( optRegexp.indexIn( binaryDir )  >= 0 )
	{
		binaryDir.remove( binRegexp );
		QFileInfo etcDirInfo { binaryDir + "/etc" };
		if ( !etcDirInfo.isDir() || !etcDirInfo.isReadable() ) { return( HierarchyType::kFlat ); }

		QFileInfo constDataDirInfo { binaryDir + "/files/data" };
		if ( !constDataDirInfo.isDir() || !constDataDirInfo.isReadable() ) { return( HierarchyType::kFlat ); }

		QFileInfo varDataDirInfo { binaryDir + "/files/lib" };
		if ( !varDataDirInfo.isDir() || !varDataDirInfo.isWritable() ) { return( HierarchyType::kFlat ); }

		QFileInfo logDirInfo { binaryDir + "/files/log" };
		if ( !logDirInfo.isDir() || !logDirInfo.isWritable() ) { return( HierarchyType::kFlat ); }

		m_systemConfigDirectory    = etcDirInfo.canonicalFilePath();
		m_systemConstDataDirectory = constDataDirInfo.canonicalFilePath();
		m_systemVarDataDirectory   = varDataDirInfo.canonicalFilePath();
		m_systemLogDirectory       = logDirInfo.canonicalFilePath();

		return ( HierarchyType::kOpt );
	}

	if ( binaryDir.startsWith( QStringLiteral( "/usr/local" ) ) )
	{
		QFileInfo etcDirInfo { "/usr/local/etc/" + m_projectName };
		if ( !etcDirInfo.isDir() || !etcDirInfo.isReadable() ) { return( HierarchyType::kFlat ); }

		QFileInfo constDataDirInfo { "/usr/local/share/" + m_projectName };
		if ( !constDataDirInfo.isDir() || !constDataDirInfo.isReadable() ) { return( HierarchyType::kFlat ); }

		QFileInfo varDataDirInfo { "/var/lib/" + m_projectName };
		if ( !varDataDirInfo.isDir() || !varDataDirInfo.isWritable() ) { return( HierarchyType::kFlat ); }

		QFileInfo logDirInfo { "/var/log/" + m_projectName };
		if ( !logDirInfo.isDir() || !logDirInfo.isWritable() ) { return( HierarchyType::kFlat ); }

		m_systemConfigDirectory    = etcDirInfo.canonicalFilePath();
		m_systemConstDataDirectory = constDataDirInfo.canonicalFilePath();
		m_systemVarDataDirectory   = varDataDirInfo.canonicalFilePath();
		m_systemLogDirectory       = logDirInfo.canonicalFilePath();

		return ( HierarchyType::kUsr );
	}
	if ( binaryDir.startsWith( QStringLiteral( "/usr" ) ) )
	{
		QFileInfo etcDirInfo { "/etc/" + m_projectName };
		if ( !etcDirInfo.isDir() || !etcDirInfo.isReadable() ) { return( HierarchyType::kFlat ); }

		QFileInfo constDataDirInfo { "/usr/share/" + m_projectName };
		if ( !constDataDirInfo.isDir() || !constDataDirInfo.isReadable() ) { return( HierarchyType::kFlat ); }

		QFileInfo varDataDirInfo { "/var/lib/" + m_projectName };
		if ( !varDataDirInfo.isDir() || !varDataDirInfo.isWritable() ) { return( HierarchyType::kFlat ); }

		QFileInfo logDirInfo { "/var/log/" + m_projectName };
		if ( !logDirInfo.isDir() || !logDirInfo.isWritable() ) { return( HierarchyType::kFlat ); }

		m_systemConfigDirectory    = etcDirInfo.canonicalFilePath();
		m_systemConstDataDirectory = constDataDirInfo.canonicalFilePath();
		m_systemVarDataDirectory   = varDataDirInfo.canonicalFilePath();
		m_systemLogDirectory       = logDirInfo.canonicalFilePath();

		return ( HierarchyType::kUsr );
	}

	if ( binaryDir.startsWith( m_homeDirectory.canonicalPath() + "/.local/bin" ) ||
	     binaryDir.startsWith( m_homeDirectory.canonicalPath() + "/bin" ) )
	{
		QFileInfo etcDirInfo { m_userConfigDirectory.canonicalPath() };
		if ( !etcDirInfo.isDir() || !etcDirInfo.isReadable() ) { return( HierarchyType::kFlat ); }

		QFileInfo constDataDirInfo { m_userConstDataDirectory.canonicalPath() };
		if ( !constDataDirInfo.isDir() || !constDataDirInfo.isReadable() ) { return( HierarchyType::kFlat ); }

		QFileInfo varDataDirInfo { m_userVarDataDirectory.canonicalPath() };
		if ( !varDataDirInfo.isDir() || !varDataDirInfo.isWritable() ) { return( HierarchyType::kFlat ); }

		QFileInfo logDirInfo { m_userLogDirectory.canonicalPath() };
		if ( !logDirInfo.isDir() || !logDirInfo.isWritable() ) { return( HierarchyType::kFlat ); }

		m_systemConfigDirectory    = etcDirInfo.canonicalFilePath();
		m_systemConstDataDirectory = constDataDirInfo.canonicalFilePath();
		m_systemVarDataDirectory   = varDataDirInfo.canonicalFilePath();
		m_systemLogDirectory       = logDirInfo.canonicalFilePath();

		return( HierarchyType::kHome );
	}

	binaryDir.remove( binRegexp );

	QFileInfo etcDirInfo { binaryDir + "/etc" };
	if ( !etcDirInfo.isDir() || !etcDirInfo.isReadable() ) { return( HierarchyType::kFlat ); }

	QFileInfo constDataDirInfo { binaryDir + "/files/data" };
	if ( !constDataDirInfo.isDir() || !constDataDirInfo.isReadable() ) { return( HierarchyType::kFlat ); }

	QFileInfo varDataDirInfo { binaryDir + "/files/lib" };
	if ( !varDataDirInfo.isDir() || !varDataDirInfo.isWritable() ) { return( HierarchyType::kFlat ); }

	QFileInfo logDirInfo { binaryDir + "/files/log" };
	if ( !logDirInfo.isDir() || !logDirInfo.isWritable() ) { return( HierarchyType::kFlat ); }

	m_systemConfigDirectory    = etcDirInfo.canonicalFilePath();
	m_systemConstDataDirectory = constDataDirInfo.canonicalFilePath();
	m_systemVarDataDirectory   = varDataDirInfo.canonicalFilePath();
	m_systemLogDirectory       = logDirInfo.canonicalFilePath();

	return ( HierarchyType::kDevelopment );
} // Paths::getHierarchyType


bool Paths::init( const QString& projectDir, const QString& configFileExtension )
{
	m_projectName = projectDir.isEmpty() ? m_currentExecutable.m_canonicalFilePath.fileName()
	                                     : projectDir;
	m_configFileExtension = configFileExtension.isEmpty() ? QStringLiteral( "conf" )
	                                                      : configFileExtension;
	m_configFileName = m_projectName + "." + m_configFileExtension;

	m_homeDirectory = QDir::homePath();
	m_tempDirectory = QDir::tempPath();

	auto configHome = QString::fromLocal8Bit( qgetenv( "XDG_CONFIG_HOME" ) );
	if ( configHome.isEmpty() )
	{
		configHome = m_homeDirectory.canonicalPath() + "/.config";
	}
	m_userConfigDirectory = configHome + "/" + m_projectName;

	auto dataHome = QString::fromLocal8Bit( qgetenv( "XDG_DATA_HOME" ) );
	if ( dataHome.isEmpty() )
	{
		dataHome = m_homeDirectory.canonicalPath() + "/.local/share";
	}
	dataHome                += "/" + m_projectName;
	m_userConstDataDirectory = dataHome + "/data";
	m_userVarDataDirectory   = dataHome + "/lib";
	m_userLogDirectory       = dataHome + "/log";

	m_hierarchyType = getHierarchyType();

	if ( m_hierarchyType == HierarchyType::kFlat )
	{
		m_systemConstDataDirectory = m_currentExecutable.m_canonicalFilePath.canonicalPath();
		m_systemVarDataDirectory   = m_currentExecutable.m_canonicalFilePath.canonicalPath();
		m_systemConfigDirectory    = m_currentExecutable.m_canonicalFilePath.canonicalPath();
		m_systemLogDirectory       = m_currentExecutable.m_canonicalFilePath.canonicalPath();
	}

	m_configFilePath = m_systemConfigDirectory.canonicalPath() + "/" + m_configFileName;

	return( true );
} // Paths::updatePaths


bool Paths::makeDefaultDirectories()
{
	bool status = true;

	if ( !m_userConfigDirectory.mkpath( m_userConfigDirectory.absolutePath() ) )       { status = false; }
	if ( !m_userVarDataDirectory.mkpath( m_userVarDataDirectory.absolutePath() ) )     { status = false; }
	if ( !m_userConstDataDirectory.mkpath( m_userConstDataDirectory.absolutePath() ) ) { status = false; }
	if ( !m_userLogDirectory.mkpath( m_userLogDirectory.absolutePath() ) )             { status = false; }
	return( status );
}


QString Paths::findConfigFile( const QString& defaultConfigFile )
{
	if ( !defaultConfigFile.isEmpty() && QFileInfo( defaultConfigFile ).isReadable() )
	{
		m_configFilePath = defaultConfigFile;
		return( defaultConfigFile );
	}

	auto fileName = QString::fromLocal8Bit( qgetenv( QCoreApplication::applicationName()
	                                                 .toUpper().toUtf8() + "_CONFIG" ) );
	if ( QFileInfo( fileName ).isReadable() )
	{
		m_configFilePath = fileName;
		return( fileName );
	}

	if ( QFileInfo( m_configFilePath ).isReadable() )
	{
		return( m_configFilePath.absoluteFilePath() );
	}

	return( QString() );
} // Paths::findConfigFile


QDir Paths::executableFileDirectory() const
{
	return( m_currentExecutable.m_canonicalFilePath.dir() );
}


const QDir& Paths::userConfigDirectory() const
{
	return( m_userConfigDirectory );
}


const QDir& Paths::systemConfigDirectory() const
{
	return( m_systemConfigDirectory );
}


const QFileInfo& Paths::configFilePath() const
{
	return( m_configFilePath );
}


const QString& Paths::configFileName() const
{
	return( m_configFileName );
}


const QString& Paths::configFileExtension() const
{
	return( m_configFileExtension );
}


const QDir& Paths::userVarDataDirectory() const
{
	return( m_userVarDataDirectory );
}


const QDir& Paths::systemVarDataDirectory() const
{
	return( m_systemVarDataDirectory );
}


const QDir& Paths::userConstDataDirectory() const
{
	return( m_userConstDataDirectory );
}


const QDir& Paths::systemConstDataDirectory() const
{
	return( m_systemConstDataDirectory );
}


const QDir& Paths::userLogDirectory() const
{
	return( m_userLogDirectory );
}


const QDir& Paths::systemLogDirectory() const
{
	return( m_systemLogDirectory );
}


const QDir& Paths::tempDirectory() const
{
	return( m_tempDirectory );
}


const QDir& Paths::homeDirectory() const
{
	return( m_homeDirectory );
}


const QString& Paths::projectName() const
{
	return( m_projectName );
}


QString Paths::executableFileName() const
{
	return( m_currentExecutable.m_canonicalFilePath.fileName() );
}


const QFileInfo& Paths::executableFilePath() const
{
	return( m_currentExecutable.m_canonicalFilePath );
}

} // namespace filesystem

} // namespace myx