/*
 * amarok2-now-playing.cpp
 * 
 * While designed for amarok 2 it also works for VLC:
 * "amarok2-now-playing vlc"
 * 
 * or any other media player that implements the org.freedesktop.MediaPlayer
 * dbus interface e.g. audacious:
 * "amarok2-now-playing org.mpris.audacious"
 * 
 * Use qdbus to get a list of dbus services and see what interfaces they
 * provide, "qdbus", "qdbus org.kde.amarok" etc.
 * 
 * Compile with the usual commands (same as any library that uses pkg-config):
 * g++ -Wall -O2 -g `pkg-config --cflags QtCore QtDBus` `pkg-config --libs QtCore QtDBus` -o amarok2-now-playing amarok2-now-playing.cpp
 */

#include <QCoreApplication>
#include <QString>
#include <QList>
#include <QVariant>
#include <QUrl>
#include <QFileInfo>

#include <QDBusConnection>
#include <QDBusMessage>
#include <QDBusVariant>
#include <QDBusArgument>

#include <cstdio>

int main( int argc, char * argv[] )
{
	QCoreApplication coreapp( argc, argv );	
	
	QDBusConnection sessionbus = QDBusConnection::sessionBus();
	
	if ( !sessionbus.isConnected() )
	{
		fprintf(stderr,"Could not connect to session bus\n");
		return 10;
	}
	
	QString program,service;
	if ( argc >= 2 )
	{
		if ( QString::fromLocal8Bit(argv[1]) == "vlc" )
		{
			service = QString::fromUtf8("org.mpris.vlc");
			program = QString::fromUtf8("VLC");
		}
		else if ( QString::fromLocal8Bit(argv[1]) == "amarok" )
		{
			service = QString::fromUtf8("org.kde.amarok");
			program = QString::fromUtf8("amarok");
		}
		else
		{
			service = QString::fromLocal8Bit(argv[1]);
			program = service.mid( service.lastIndexOf('.') + 1 );
		}
	}
	else
	{
		service = QString::fromUtf8("org.kde.amarok");
		program = QString::fromUtf8("amarok");
	}
	
	if ( service.isEmpty() )
	{
		fprintf(stderr,"Empty service!\n");
		return 5;
	}
	
	QString path = QString::fromUtf8("/Player");
	QString interface = QString::fromUtf8("org.freedesktop.MediaPlayer");
	QString method = QString::fromUtf8("GetMetadata");
	QDBusMessage getmetadata = QDBusMessage::createMethodCall(
		service,
		path,
		interface,
		method
	);
	
	QDBusMessage metadatamsg = sessionbus.call( getmetadata, QDBus::Block, 30*1000 );
	
	if ( metadatamsg.type() != QDBusMessage::ReplyMessage )
	{
		fprintf(stderr,"Unexpected reply type()=%d\n",metadatamsg.type());
		fprintf(stderr,"errorMessage()='%s'\n",metadatamsg.errorMessage().toLocal8Bit().constData());
		return 20;
	}
	
	QList<QVariant> args = metadatamsg.arguments();
	
	if ( args.size() == 1 )
	{
		QVariantMap varmap = qdbus_cast<QVariantMap>(args.first());

		/*
		 * amarok keys:
		 * album
		 * artist
		 * arturl
		 * audio-bitrate
		 * audio-samplerate
		 * comment
		 * genre
		 * location
		 * mtime
		 * rating
		 * time
		 * title
		 * tracknumber
		 * year
		 */
#if 0
		for ( QVariantMap::const_iterator it = varmap.constBegin(); it != varmap.constEnd(); ++ it )
		{
			printf("key=%s\n",it.key().toLocal8Bit().constData());
		}
#endif
		
		QString artist = varmap.value("artist").toString();
		QString title = varmap.value("title").toString();
		if ( !(artist.isEmpty() || title.isEmpty()) )
		{
			printf(
				"%s playing (%s - %s",
				program.toLocal8Bit().constData(),
				artist.toLocal8Bit().constData(),
				title.toLocal8Bit().constData()
			);
			
			if ( varmap.contains("audio-bitrate") )
			{
				printf(" - %dkbps)",varmap.value("audio-bitrate").toInt());
			}
			else
			{
				printf(")");
			}
		}
		else if ( varmap.contains("location") )
		{
			/* amarok gives URI with %20 for space etc. while vlc just gives the file name and path */
			QString uri = QUrl::fromPercentEncoding(varmap.value("location").toString().toUtf8());
			QFileInfo fi(uri);
			printf(
				"%s playing (%s)",
				program.toLocal8Bit().constData(),
				fi.fileName().toLocal8Bit().constData()
			);
		}
		else
		{
			fprintf(stderr,"Cannot find artist+title or file\n");
			return 50;
		}
		
		if ( varmap.contains("time") || varmap.contains("length") )
		{
			int length = 0;
			if ( varmap.contains("time") )
			{
				length = varmap.value("time").toInt();
			}
			else
			{
				length = varmap.value("length").toInt() / 1000;
			}
			
			QDBusMessage getpos = QDBusMessage::createMethodCall(
				service,
				path,
				interface,
				QString::fromUtf8("PositionGet")
			);
			
			QDBusMessage posmsg = sessionbus.call( getpos, QDBus::Block, 30*1000 );
			
			if ( (posmsg.type() == QDBusMessage::ReplyMessage) && (posmsg.arguments().size() == 1) )
			{
				int pos = qdbus_cast<int>(posmsg.arguments().first());
				int len_h = length / (60*60);
				int len_m = (length - len_h * (60*60)) / (60);
				int len_s = length - (len_h * (60*60) + len_m * (60));
				
				int pos_h = pos / (60*60*1000);
				int pos_m = (pos - pos_h * (60*60*1000)) / (60*1000);
				int pos_s = (pos - (pos_h * (60*60*1000) + pos_m * (60*1000))) / 1000;
				
				if ( len_h == 0 )
				{
					printf(
						" - (%d:%02d/%d:%02d)\n",
						pos_m,
						pos_s,
						len_m,
						len_s
					);
				}
				else
				{
					printf(
						" - (%d:%02d:%02d/%d:%02d:%02d)\n",
						pos_h,
						pos_m,
						pos_s,
						len_h,
						len_m,
						len_s
					);
				}
			}
			else
			{
				printf("\n");
			}
		}
		else
		{
			printf("\n");
		}
	}
	else
	{
		fprintf(stderr,"Unexpected data received size()=%d\n",args.size());
		return 40;
	}
	
	return 0;
}