/**************************************************************************
 *   Copyright (C) 2006-2007 by Danny Kukawka                              *
 *                              <dkukawka@suse.de>, <danny.kukawka@web.de> *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of version 2 of the GNU General Public License     *
 *   as published by the Free Software Foundation.                         *
 *                                                                         *
 *   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.          *
 ***************************************************************************/

/*! 
 * \file 	dbusInterface.cpp
 * \brief 	In this file can be found the functionality to connect to 
 *		the HAL daemon via D-Bus, to handle D-Bus calls/events and to
 *		provide wrapper to HAL lib and functions
 * \author 	Danny Kukawka, <dkukawka@suse.de>, <danny.kukawka@web.de>
 * \date    	2006-2007
 */
 
  // KDE Header
#include <tdelocale.h>

// DBUS - Header
#include "dbusInterface.h"

// system headers
#include <iostream>

static void* myInstance = 0;

/*! The default constructor of the class dbusInterface. */
dbusInterface::dbusInterface(){
	kdDebugFuncIn(trace);

	dbus_is_connected = false;
	acquiredPolicyPower = false;

	// add pointer to this for filter_function()
	myInstance=this;
	// init connection to dbus
	if(!initDBUS()) {
		kdError() << "Can't connect to D-Bus" << endl;
		m_dBusQtConnection = NULL;
	}

	kdDebugFuncOut(trace);
}

/*! This is the default destructor of class dbusPowersaveConnection. */
dbusInterface::~dbusInterface(){
	kdDebugFuncIn(trace);

	close();
	myInstance = NULL;

	kdDebugFuncOut(trace);
}

/*! 
 * This function return information about connection status to the DBUS daemon.
 * \return boolean with the state of the connection to D-Bus
 * \retval true if connected
 * \retval false if disconnected
 */
bool dbusInterface::isConnectedToDBUS() {
	return dbus_is_connected;
}

/*! 
 * This function return information if the org.freedesktop.Policy.Power 
 * interface was claimed.
 * \return boolean with the status of claim the interface
 * \retval true if acquired 
 * \retval false if not
 */
bool dbusInterface::acquiredPolicyPowerInterface() {
	return acquiredPolicyPower;
}

/*! 
 * This function try a reconnect to D-Bus and HAL  daemon.
 * \return boolean with the result of the operation
 * \retval true if successful reconnected to D-Bus and HAL
 * \retval false if unsuccessful
 */
bool dbusInterface::reconnect() {
	// close D-Bus connection
	close();
	// init D-Bus conntection and HAL context
	return (initDBUS());
}

/*! 
 * This function close the connection to powersave over the D-Bus daemon.
 * \return boolean with the result of the operation
 * \retval true if successful closed the connection
 * \retval false if any problems
 */
bool dbusInterface::close() {
	if ( m_dBusQtConnection != NULL ) {
		releasePolicyPowerIface();
		m_dBusQtConnection->close();
		m_dBusQtConnection = NULL;
	}
	dbus_is_connected = false;

	return true;
}

/* ----> D-Bus section :: START <---- */

/*! 
 * This function initialise the connection to the D-Bus daemon.
 * \return boolean with the result of the operation
 * \retval true if successful initialised D-Bus connection
 * \retval false if unsuccessful
 */
bool dbusInterface::initDBUS(){
	kdDebugFuncIn(trace);

	dbus_is_connected = false;

        DBusError error;
        dbus_error_init(&error);
	
	dbus_connection = dbus_bus_get( DBUS_BUS_SYSTEM, &error );

	if (dbus_connection == NULL){
		kdError() << "Failed to open connection to system message bus: " << error.message << endl;
		dbus_error_free (&error);
		return false;
	}

	if ( dbus_error_is_set( &error ) ) {
		kdError() << "Failed to register connection with system message bus: " << error.message << endl;
		return false;
	}

	acquirePolicyPowerIface();

	dbus_connection_set_exit_on_disconnect( dbus_connection, false );

        /* add the filter function which should be executed on events on the bus */
        if ( ! dbus_connection_add_filter( dbus_connection, filterFunction, this, NULL) ) {
                kdFatal() << "Error: Not enough memory to add filter to dbus connection" << endl;
                exit(EXIT_FAILURE);
        }

        /* add a match rule to catch all signals going through the bus with D-Bus interface */
	dbus_bus_add_match( dbus_connection, "type='signal',"
			    "interface='org.freedesktop.DBus'," 
			    "member='NameOwnerChanged'", NULL);

	/* add a match rule to catch all signals going through the bus with ConsoleKit Interface */
	dbus_bus_add_match( dbus_connection, "type='signal',"
			    "interface='org.freedesktop.ConsoleKit.Session'," 
			    "member='ActiveChanged'", NULL);

	m_dBusQtConnection = new DBusQt::Connection(this);
        m_dBusQtConnection->dbus_connection_setup_with_qt_main(dbus_connection);

	dbus_is_connected = true;

	kdDebugFuncOut(trace);
	return true;
}

/*!
 * This function acquire the org.freedesktop.Policy.Power interface
 * \return boolean with the result of the operation
 * \retval true 	if successful acquired the interface
 * \retval false 	if unsuccessful
 */
bool dbusInterface::acquirePolicyPowerIface(){
	kdDebugFuncIn(trace);

	if (dbus_connection == NULL) {
		kdDebugFuncOut(trace);
		return false;
	}

	switch (dbus_bus_request_name(dbus_connection, "org.freedesktop.Policy.Power",
				      DBUS_NAME_FLAG_REPLACE_EXISTING, NULL)) {
		case DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER:
			kdDebug() << "Acquired org.freedesktop.Policy.Power interface" << endl;
			acquiredPolicyPower = true;
			break;
		case DBUS_REQUEST_NAME_REPLY_IN_QUEUE:
			kdWarning() << "Queued to acquire org.freedesktop.Policy.Power interface" << endl;
			acquiredPolicyPower = false;
			break;
		default:
			kdWarning() << "Unknown error while acquire org.freedesktop.Policy.Power interface" << endl;
			acquiredPolicyPower = false;
			break;
	}

	kdDebugFuncOut(trace);
	return acquiredPolicyPower;
}

/*! 
 * This function release the org.freedesktop.Policy.Power interface
 * \return boolean with the result of the operation
 * \retval true 	if successful acquired the interface
 * \retval false 	if unsuccessful
 */
bool dbusInterface::releasePolicyPowerIface(){
	kdDebugFuncIn(trace);

	int result;
	bool retval = false;
	DBusError error;

	if (dbus_connection == NULL) {
		kdDebugFuncOut(trace);
		return false;
	}

        dbus_error_init(&error);

	result = dbus_bus_release_name(dbus_connection, "org.freedesktop.Policy.Power", &error);

	if ( dbus_error_is_set( &error ) ) {
		kdError() << "Failed to release org.freedesktop.Policy.Power: " << error.message << endl;
		dbus_error_free(&error);
	} else {
		switch (result) {
			case DBUS_RELEASE_NAME_REPLY_RELEASED:
				kdDebug() << "Released org.freedesktop.Policy.Power interface" << endl;
				retval = true;
				acquiredPolicyPower = false;
				break;
			case DBUS_RELEASE_NAME_REPLY_NOT_OWNER:
				kdWarning() << "Couldn't release org.freedesktop.Policy.Power, not the owner" << endl;
				break;
			case DBUS_RELEASE_NAME_REPLY_NON_EXISTENT:
				kdWarning() << "Couldn't release org.freedesktop.Policy.Power, Iface not existing" << endl;
				break;
			default:
				kdWarning() << "Couldn't release org.freedesktop.Policy.Power, unknown error" << endl;
				break;
		}
	}
		
	return retval;
	kdDebugFuncOut(trace);
}

/*! 
 * This function check if the org.freedesktop.Policy.Power 
 * interface is owned by someone
 * \return boolean with the result of the operation
 * \retval true 	if the interface is owned by someone
 * \retval false 	if else
 */
bool dbusInterface::isPolicyPowerIfaceOwned(){
	kdDebugFuncIn(trace);

	bool retval = false;
	DBusError error;

	if (dbus_connection == NULL) {
		kdDebugFuncOut(trace);
		return false;
	}

        dbus_error_init(&error);

	retval = dbus_bus_name_has_owner(dbus_connection, "org.freedesktop.Policy.Power", &error);

	if ( dbus_error_is_set( &error ) ) {
		kdError() << "Failed to check if org.freedesktop.Policy.Power has an owner: " << error.message << endl;
		dbus_error_free(&error);
	}

	kdDebugFuncOut(trace);
	return retval;
}

/* ----> DBUS section :: END   <---- */

/* ----> D-Bus methode calls functions :: START <---- */
/*! 
 * This function call a D-Bus method
 * \param interface	TQString with te dbus interface
 * \param path		TQString with the object path
 * \param object	TQString with the object name
 * \param method	TQString with the name of the methode
 * \param first_arg_type integer with the dbus type of the first argument
 * \param ... 		more arguments
 * \return 		If the query was successful or not
 */
bool dbusInterface::dbusSystemMethodCall( TQString interface, TQString path, TQString object, TQString method,
			   	    int first_arg_type, ... ) {
	kdDebugFuncIn(trace);
	
	bool _ret = false;
        va_list var_args;

        va_start(var_args, first_arg_type);
	_ret = dbusMethodCall( interface, path, object, method, DBUS_BUS_SYSTEM,
			       NULL, -1, first_arg_type, var_args);
	va_end(var_args);
	
	kdDebugFuncOut(trace);
	return _ret;
}


/*! 
 * This overloaded function call a D-Bus method on the D-Bus system bus with a return value
 * \param interface	 TQString with the dbus interface
 * \param path		 TQString with the object path
 * \param object	 TQString with the object name
 * \param method	 TQString with the name of the method
 * \param retvalue	 void pointer to arguments, if NULL we make a simple call
 * \param retval_type    Integer with the dbus type of the return value, set to -1 if retvalue is NULL
 * \param first_arg_type Integer with the dbus type of the first argument followed by the value
 * \return 		 If the query was successful or not
 */
bool dbusInterface::dbusSystemMethodCall( TQString interface, TQString path, TQString object, TQString method,
				    void *retvalue, int retval_type, int first_arg_type, ... ) {
	kdDebugFuncIn(trace);
	
	bool _ret = false;
        va_list var_args;

        va_start(var_args, first_arg_type);
	_ret = dbusMethodCall( interface, path, object, method, DBUS_BUS_SYSTEM, 
			       retvalue, retval_type, first_arg_type, var_args);
	va_end(var_args);
	
	kdDebugFuncOut(trace);
	return _ret;
}


/*! 
 * This function call a D-Bus method with a return value
 * \param interface	 TQString with the dbus interface
 * \param path		 TQString with the object path
 * \param object	 TQString with the object name
 * \param method	 TQString with the name of the method
 * \param dbus_type	 DBusBusType with the D-Bus BUS Type
 * \param retvalue	 void pointer to arguments, if NULL we make a simple call
 * \param retval_type    Integer with the dbus type of the return value, set to -1 if retvalue is NULL
 * \param first_arg_type Integer with the dbus type of the first argument followed by the value
 * \param var_args	 va_list with more arguments
 * \return 		 If the query was successful or not
 */
bool dbusInterface::dbusMethodCall( TQString interface, TQString path, TQString object, TQString method,
			      DBusBusType dbus_type, void *retvalue, int retval_type, int first_arg_type,
			      va_list var_args ) {
	kdDebugFuncIn(trace);

	DBusMessage *message;
	DBusMessage *reply;
	DBusError    error;
	bool ret = false;
	
	dbus_error_init(&error); 

	dbus_connection = dbus_bus_get(dbus_type, &error);
	
	if (dbus_error_is_set(&error)) {
		kdError() << "Could not get dbus connection: " << error.message << endl;
		dbus_error_free(&error);
		goto out;
	}

	message = dbus_message_new_method_call( interface.ascii(), path.ascii(), object.ascii(), method.ascii() );
	dbus_message_append_args_valist(message, first_arg_type, var_args);

	if (retvalue == NULL) {
		if (!dbus_connection_send(dbus_connection, message, NULL)) {
			kdError() << "Could not send method call." << endl;
			dbus_message_unref( message );
			goto out;
		}
	} else {
		reply = dbus_connection_send_with_reply_and_block(dbus_connection, message, -1, &error);

		if (dbus_error_is_set(&error)) {
			kdError() << "Could not send dbus message: " << error.message << endl;
			dbus_message_unref(message);
			dbus_error_free(&error);
			goto out;
		}

		int type = dbus_message_get_type(reply);
		if (type == DBUS_MESSAGE_TYPE_METHOD_RETURN) {
			if (!dbus_message_get_args(reply, &error, retval_type, retvalue, DBUS_TYPE_INVALID)){
				if (dbus_error_is_set(&error)) {
					kdError() << "Could not get argument from reply: " 
						  << error.message << endl;
					dbus_error_free(&error);
				}
				dbus_message_unref(reply);
				dbus_message_unref(message);
				goto out;
			}
		} else {
			kdError() << "Revieved invalid DBUS_MESSAGE_TYPE: " << type 
				  << "expected: " << DBUS_MESSAGE_TYPE_METHOD_RETURN << endl;
			dbus_message_unref(reply);
			dbus_message_unref(message);
			goto out;
		}
	}

	ret = true;	// if we are here, everything should be okay
	dbus_message_unref(message);
	dbus_connection_flush(dbus_connection);

out:
	kdDebugFuncOut(trace);
        return ret;
}

/* ----> D-Bus methode calls functions :: END  <---- */
/* ---> PolicyKit method call section :: START <--- */

/*!
 * Check if the user is privileged to a special privilege
 * \param privilege	TQString with the name of the requested privilege
 * \param udi		TQString with the UDI.
 * \param ressource	TQString with the name of the ressource
 * \param user		TQString with the name of the user. If empty the current user is used.
 * \return int with info if the user is allowed or not.
 * \retval 0		if not allowed
 * \retval 1		if allowed
 * \retval -1		if a error occurs or we could not query the interface
 */
int dbusInterface::isUserPrivileged(TQString privilege, TQString udi, TQString ressource, TQString user) {
	kdDebugFuncIn(trace);

	const char *_unique_name;
	const char *_user;
	const char *_privilege;	
	
	int retval = -1;

	if (user.isEmpty() || user.isNull()) 
		_user = getenv("USER"); 
	else 
		_user = user.latin1();

	if (_user == NULL || privilege.isEmpty()) 
		goto out;

	_unique_name = dbus_bus_get_unique_name(dbus_connection);
	_privilege = privilege.latin1();

	// not sure if we need this, but to avoid problems
	dbus_bool_t _retval;
	const char *_ressource;
	_ressource = ressource.latin1();

	if (!dbusSystemMethodCall( "org.freedesktop.PolicyKit",
				   "/org/freedesktop/PolicyKit/Manager",
				   "org.freedesktop.PolicyKit.Manager",
				   "IsUserPrivileged",
				   &_retval, DBUS_TYPE_BOOLEAN,
				   DBUS_TYPE_STRING, &_unique_name,
				   DBUS_TYPE_STRING, &_user,
				   DBUS_TYPE_STRING, &_privilege,
				   DBUS_TYPE_STRING, &_ressource,
				   DBUS_TYPE_INVALID)) {
		retval = -1;	// only to be sure we have no changes trough the call
	} else {
		retval = (int) _retval;
	}

out:
	kdDebugFuncOut(trace);
	return retval;
}
/* ---> PolicyKit method call section :: END   <--- */

/*!
 * Use this TQT_SLOT to emit a reviced messages to the kpowersave.
 * NOTE: Because of the filter function this need to be a public function.
 *       Don't use this function in any other place than this class.
 * \param  type enum with the type of the message
 * \param  message String with the message
 * \param  string String with additional info
 */
void dbusInterface::emitMsgReceived( msg_type type, TQString message, TQString string ) {
	
	if (message.startsWith("dbus.terminate"))
		dbus_is_connected = false;

	if (type == POLICY_POWER_OWNER_CHANGED) {
		if (message.startsWith("NOW_OWNER"))
			acquiredPolicyPower = true;
		else 
			acquiredPolicyPower = false;
	}

	emit msgReceived_withStringString( type, message, string );
}

#include "dbusInterface.moc"
// --> functions which are not member of the class ...

/*! 
 * This function is needed filter function for the D-Bus connection to filter
 * all needed messages from the bus which are needful for KPowersave. 
 * \param connection	existing connection to the D-Bus daemon
 * \param message 	the recieved message from the D-Bus daemon
 * \param data		void pointer (see dbus bindings for more information)
 * \return DBusHandlerResult
 */
DBusHandlerResult 
filterFunction (DBusConnection *connection, DBusMessage *message, void */*data*/) {
 	kdDebugFuncIn(trace);
	
	bool reply_wanted;
	char *value;
	TQString ifaceType;

	DBusError error;
        dbus_error_init( &error );

	if (dbus_message_is_signal (message,
				    DBUS_INTERFACE_LOCAL,
				    "Disconnected")){
		((dbusInterface*) myInstance)->emitMsgReceived( DBUS_EVENT, "dbus.terminate", 0 );
		dbus_connection_unref(connection);
		kdDebugFuncOut(trace);
		return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
	}

        if ( dbus_message_get_type( message ) != DBUS_MESSAGE_TYPE_SIGNAL ) {
                if (trace) kdDebug() << "recieved message, but wasn't from type DBUS_MESSAGE_TYPE_SIGNAL" << endl;
		kdDebugFuncOut(trace);
		return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
        }

	ifaceType = dbus_message_get_interface( message );
        if (ifaceType == NULL) {
                kdDebug() << "Received message from invalid interface" << endl;
                kdDebugFuncOut(trace);
		return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
        }

	reply_wanted = !dbus_message_get_no_reply( message );

	if (ifaceType.startsWith(DBUS_INTERFACE_DBUS)) {
		if(trace) kdDebug() << "Received from DBUS_INTERFACE_DBUS" << endl;
		/* get the name of the signal */
		const char *signal = dbus_message_get_member( message );
		
		/* get the first argument. This must be a string at the moment */
		dbus_message_get_args( message, &error, DBUS_TYPE_STRING, &value, DBUS_TYPE_INVALID );
	
		if ( dbus_error_is_set( &error ) ) {
			kdWarning() << "Received signal " << error.message << " but no string argument" << endl;
			dbus_error_free( &error );
			kdDebugFuncOut(trace);
			return DBUS_HANDLER_RESULT_HANDLED;
		}
	
		if (trace) kdDebug() << "filter_function::SIGNAL=" << signal << " VALUE=" << value << endl;
	
		/* our name is... */
		if ( ! strcmp( signal, "NameAcquired" ) ) {
			kdDebugFuncOut(trace);
			return DBUS_HANDLER_RESULT_HANDLED;
		}
		
		else if ( ! strcmp( signal, "NameOwnerChanged" )) {
			char *service;
			char *old_owner;
			char *new_owner;
			
                	if (dbus_message_get_args (message, NULL, DBUS_TYPE_STRING, &service,
                                                   DBUS_TYPE_STRING, &old_owner,
                                                   DBUS_TYPE_STRING, &new_owner, DBUS_TYPE_INVALID)) {
				if (!strcmp(service, "org.freedesktop.Policy.Power")) {
					const char *own_name;
					
					own_name = dbus_bus_get_unique_name(((dbusInterface*) myInstance)->get_DBUS_connection());

					if (!strcmp(new_owner, own_name)) {
						kdDebug() << "=== now owner of org.freedesktop.Policy.Power ===" << endl;
						// we have now again the ower of the name!
						((dbusInterface*) myInstance)->emitMsgReceived( POLICY_POWER_OWNER_CHANGED,
											  "NOW_OWNER", 
											  NULL );
					} else {
						// some other has now the interface
						kdDebug() << "=== someone owner of org.freedesktop.Policy.Power ===" << endl;
						((dbusInterface*) myInstance)->emitMsgReceived( POLICY_POWER_OWNER_CHANGED,
											  "OTHER_OWNER", 
											  NULL );
					}
				}
			}
		}
		kdDebugFuncOut(trace);
		return DBUS_HANDLER_RESULT_HANDLED;	
	} else if (ifaceType.startsWith("org.freedesktop.ConsoleKit.Session")) {
		kdDebug() << "Received from org.freedesktop.ConsoleKit.Session" << endl;

		const char *session = dbus_message_get_path (message);
		const char *signal = dbus_message_get_member( message );
		
		if (! strcmp(signal, "ActiveChanged")) {
			dbus_bool_t active;

			if (dbus_message_get_args( message, &error, DBUS_TYPE_BOOLEAN, &active, DBUS_TYPE_INVALID )) {
				((dbusInterface*) myInstance)->emitMsgReceived( CONSOLEKIT_SESSION_ACTIVE, 
									  session, TQString("%1").arg((int)active));
			} else {
				if (dbus_error_is_set( &error )) dbus_error_free( &error );
			}
		} else {
			kdDebug() << "Received unknown signal from org.freedesktop.ConsoleKit.Session: "
				  << signal << endl;
			kdDebugFuncOut(trace);
			return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
		}
		kdDebugFuncOut(trace);
		return DBUS_HANDLER_RESULT_HANDLED;
	} else {
		kdDebugFuncOut(trace);
		return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
	}
}

// --> some functions to get private members

//! to get the current connection to D-Bus
DBusConnection * dbusInterface::get_DBUS_connection() {
	return dbus_connection;
}