Started calendar invoker and bug fixes

13 files changed, 301 insertions, 45 deletions

diff --git a/src/uscxml/Factory.cpp b/src/uscxml/Factory.cpp
index 7ac3b98..0d5f401 100644
--- a/src/uscxml/Factory.cpp
+++ b/src/uscxml/Factory.cpp
@@ -45,6 +45,10 @@
 #   include "uscxml/plugins/invoker/ffmpeg/FFMPEGInvoker.h"
 # endif
 
+# ifdef LIBICAL_FOUND
+#   include "uscxml/plugins/invoker/calendar/CalendarInvoker.h"
+# endif
+
 # ifdef V8_FOUND
 #   include "uscxml/plugins/datamodel/ecmascript/v8/V8DataModel.h"
 # endif
diff --git a/src/uscxml/Factory.h b/src/uscxml/Factory.h
index 9507d07..58002fe 100644
--- a/src/uscxml/Factory.h
+++ b/src/uscxml/Factory.h
@@ -14,6 +14,10 @@
 
 namespace uscxml {
 
+inline bool isnan(double x) {
+  return x != x;
+}
+
 // see http://stackoverflow.com/questions/228005/alternative-to-itoa-for-converting-integer-to-string-c
 template <typename T> std::string toStr(T tmp) {
 	std::ostringstream out;
@@ -30,9 +34,9 @@ template <typename T> T strTo(std::string tmp) {
 }
 
 inline bool isNumeric( const char* pszInput, int nNumberBase) {
-	std::string base = ".0123456789ABCDEF";
+	std::string base = ".-0123456789ABCDEF";
 	std::string input = pszInput;
-	return (input.find_first_not_of(base.substr(0, nNumberBase + 1)) == std::string::npos);
+	return (input.find_first_not_of(base.substr(0, nNumberBase + 2)) == std::string::npos);
 }
 
 class InterpreterImpl;
diff --git a/src/uscxml/Interpreter.cpp b/src/uscxml/Interpreter.cpp
index 16fb503..4e33c8b 100644
--- a/src/uscxml/Interpreter.cpp
+++ b/src/uscxml/Interpreter.cpp
@@ -382,12 +382,12 @@ void InterpreterImpl::normalize(Arabica::DOM::Element<std::string>& scxml) {
 }
 
 void InterpreterImpl::receiveInternal(const Event& event) {
-	//std::cout << _name << " receiveInternal: " << event.name << std::endl;
+	std::cout << _name << " receiveInternal: " << event.name << std::endl;
 	_internalQueue.push_back(event);
 }
 
 void InterpreterImpl::receive(const Event& event, bool toFront)   {
-	//std::cout << _name << " receive: " << event.name << std::endl;
+	std::cout << _name << " receive: " << event.name << std::endl;
 	if (toFront) {
 		_externalQueue.push_front(event);
 	} else {
@@ -695,6 +695,8 @@ void InterpreterImpl::send(const Arabica::DOM::Node<std::string>& element) {
 					e.name = "error.execution";
 					receiveInternal(e);
 				}
+			} else if (sendReq.content.length() > 0) {
+				sendReq.data = Data::fromJSON(sendReq.content);
 			}
 		}
 	} catch (Event e) {
@@ -822,7 +824,10 @@ void InterpreterImpl::invoke(const Arabica::DOM::Node<std::string>& element) {
 						e.name = "error.execution";
 						receiveInternal(e);
 					}
+				} else if (invokeReq.content.length() > 0) {
+					invokeReq.data = Data::fromJSON(invokeReq.content);
 				}
+
 			}
 		} catch (Event e) {
 			LOG(ERROR) << "Syntax error in send element content:" << std::endl << e << std::endl;
@@ -1062,18 +1067,16 @@ void InterpreterImpl::executeContent(const Arabica::DOM::Node<std::string>& cont
 	} else if (boost::iequals(TAGNAME(content), _xmlNSPrefix + "log")) {
 		// --- LOG --------------------------
 		Arabica::DOM::Element<std::string> logElem = (Arabica::DOM::Element<std::string>)content;
+		if (logElem.hasAttribute("label"))
+			std::cout << logElem.getAttribute("label") << ": ";
 		if (logElem.hasAttribute("expr")) {
-			if (logElem.hasAttribute("label"))
-				std::cout << logElem.getAttribute("label") << ": ";
-			if (_dataModel) {
-				try {
-					std::cout << _dataModel.evalAsString(logElem.getAttribute("expr")) << std::endl;
-				}
-				CATCH_AND_DISTRIBUTE("Syntax error in expr attribute of log element:")
-			} else {
-				if (logElem.hasAttribute("label"))
-					std::cout << std::endl;
+			try {
+				std::cout << _dataModel.evalAsString(logElem.getAttribute("expr")) << std::endl;
 			}
+			CATCH_AND_DISTRIBUTE("Syntax error in expr attribute of log element:")
+		} else {
+			if (logElem.hasAttribute("label"))
+				std::cout << std::endl;			
 		}
 	} else if (boost::iequals(TAGNAME(content), _xmlNSPrefix + "assign")) {
 		// --- ASSIGN --------------------------
@@ -1345,9 +1348,12 @@ Arabica::DOM::Node<std::string> InterpreterImpl::getState(const std::string& sta
 
 FOUND:
 	if (target.size() > 0) {
-		assert(target.size() == 1);
-		_cachedStates[stateId] = target[0];
-		return target[0];
+		for (int i = 0; i < target.size(); i++) {
+			if (!isInEmbeddedDocument(target[i])) {
+				_cachedStates[stateId] = target[i];
+				return target[i];
+			}
+		}
 	}
 	// return the empty node
 	return Arabica::DOM::Node<std::string>();
@@ -1549,6 +1555,21 @@ bool InterpreterImpl::isFinal(const Arabica::DOM::Node<std::string>& state) {
 	return false;
 }
 
+bool InterpreterImpl::isInEmbeddedDocument(const Node<std::string>& node) {
+	// a node is in an embedded document if there is a content element in its parents
+	Node<std::string> parent = node;
+	while(parent) {
+		if(parent == _scxml) {
+			return false;
+		}
+		if(boost::iequals(parent.getLocalName(), "content")) {
+			return true;
+		}
+		parent = parent.getParentNode();
+	}
+	return false;
+}
+
 bool InterpreterImpl::isInitial(const Arabica::DOM::Node<std::string>& state) {
 	if (!isState(state))
 		return false;
diff --git a/src/uscxml/Interpreter.h b/src/uscxml/Interpreter.h
index d4ec389..56454db 100644
--- a/src/uscxml/Interpreter.h
+++ b/src/uscxml/Interpreter.h
@@ -215,11 +215,12 @@ public:
 	static bool isParallel(const Arabica::DOM::Node<std::string>& state);
 	static bool isCompound(const Arabica::DOM::Node<std::string>& state);
 	static bool isDescendant(const Arabica::DOM::Node<std::string>& s1, const Arabica::DOM::Node<std::string>& s2);
-
+	
 	static std::vector<std::string> tokenizeIdRefs(const std::string& idRefs);
 	static std::string spaceNormalize(const std::string& text);
 
-	bool isInitial(const Arabica::DOM::Node<std::string>& state);
+	bool isInEmbeddedDocument(const Arabica::DOM::Node<std::string>& node);
+	bool isInitial(const Arabica::DOM::Node<std::string>& state);	
 	Arabica::XPath::NodeSet<std::string> getInitialStates(Arabica::DOM::Node<std::string> state = Arabica::DOM::Node<std::string>());
 	static Arabica::XPath::NodeSet<std::string> getChildStates(const Arabica::DOM::Node<std::string>& state);
 	static Arabica::DOM::Node<std::string> getParentState(const Arabica::DOM::Node<std::string>& element);
diff --git a/src/uscxml/interpreter/InterpreterDraft6.cpp b/src/uscxml/interpreter/InterpreterDraft6.cpp
index abea1ae..b3e76bd 100644
--- a/src/uscxml/interpreter/InterpreterDraft6.cpp
+++ b/src/uscxml/interpreter/InterpreterDraft6.cpp
@@ -278,7 +278,9 @@ void InterpreterDraft6::mainEventLoop() {
 				}
 				if (boost::iequals(autoForward, "true")) {
 					try {
-						_invokers[invokeId].send(_currEvent);
+						// do not autoforward to invokers that send to #_parent from the SCXML IO Processor!
+						if (!boost::equals(_currEvent.getOriginType(), "http://www.w3.org/TR/scxml/#SCXMLEventProcessor"))
+							_invokers[invokeId].send(_currEvent);
 					} catch(...) {
 						LOG(ERROR) << "Exception caught while sending event to invoker " << invokeId;
 					}
diff --git a/src/uscxml/plugins/datamodel/ecmascript/JavaScriptCore/JSCDataModel.cpp b/src/uscxml/plugins/datamodel/ecmascript/JavaScriptCore/JSCDataModel.cpp
index 2143f5f..1326fb9 100644
--- a/src/uscxml/plugins/datamodel/ecmascript/JavaScriptCore/JSCDataModel.cpp
+++ b/src/uscxml/plugins/datamodel/ecmascript/JavaScriptCore/JSCDataModel.cpp
@@ -57,6 +57,7 @@ JSClassDefinition JSCDataModel::jsInClassDef = { 0, 0, "In", 0, 0, 0, 0, 0, 0, 0
 JSClassDefinition JSCDataModel::jsPrintClassDef = { 0, 0, "print", 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, jsPrint, 0, 0, 0 };
 
 JSClassDefinition JSCDataModel::jsIOProcessorsClassDef = { 0, 0, "ioProcessors", 0, 0, 0, 0, 0, jsIOProcessorHasProp, jsIOProcessorGetProp, 0, 0, jsIOProcessorListProps, 0, 0, 0, 0 };
+JSClassDefinition JSCDataModel::jsInvokersClassDef = { 0, 0, "invokers", 0, 0, 0, 0, 0, jsInvokerHasProp, jsInvokerGetProp, 0, 0, jsInvokerListProps, 0, 0, 0, 0 };
 
 boost::shared_ptr<DataModelImpl> JSCDataModel::create(InterpreterImpl* interpreter) {
 	boost::shared_ptr<JSCDataModel> dm = boost::shared_ptr<JSCDataModel>(new JSCDataModel());
@@ -81,6 +82,12 @@ boost::shared_ptr<DataModelImpl> JSCDataModel::create(InterpreterImpl* interpret
 	JSObjectSetProperty(dm->_ctx, JSContextGetGlobalObject(dm->_ctx), printName, jsPrint, kJSPropertyAttributeNone, NULL);
 	JSStringRelease(inName);
 
+	JSClassRef jsInvokerClassRef = JSClassCreate(&jsInvokersClassDef);
+	JSObjectRef jsInvoker = JSObjectMake(dm->_ctx, jsInvokerClassRef, dm.get());
+	JSStringRef invokerName = JSStringCreateWithUTF8CString("_invokers");
+	JSObjectSetProperty(dm->_ctx, JSContextGetGlobalObject(dm->_ctx), invokerName, jsInvoker, kJSPropertyAttributeNone, NULL);
+	JSStringRelease(invokerName);
+
 	JSClassRef jsIOProcClassRef = JSClassCreate(&jsIOProcessorsClassDef);
 	JSObjectRef jsIOProc = JSObjectMake(dm->_ctx, jsIOProcClassRef, dm.get());
 	JSStringRef ioProcName = JSStringCreateWithUTF8CString("_ioprocessors");
@@ -109,7 +116,6 @@ boost::shared_ptr<DataModelImpl> JSCDataModel::create(InterpreterImpl* interpret
 		JSObjectSetProperty(dm->_ctx, globalObject, JSStringCreateWithUTF8CString("document"), documentObject, kJSPropertyAttributeReadOnly | kJSPropertyAttributeDontDelete, NULL);
 	}
 
-	dm->eval(Element<std::string>(), "_invokers = {};");
 	dm->eval(Element<std::string>(), "_x = {};");
 
 	return dm;
@@ -576,4 +582,44 @@ void JSCDataModel::jsIOProcessorListProps(JSContextRef ctx, JSObjectRef object,
 	}	
 }
 
+	
+bool JSCDataModel::jsInvokerHasProp(JSContextRef ctx, JSObjectRef object, JSStringRef propertyName) {
+	JSCDataModel* INSTANCE = (JSCDataModel*)JSObjectGetPrivate(object);
+	std::map<std::string, Invoker> invokers = INSTANCE->_interpreter->getInvokers();
+	
+	size_t maxSize = JSStringGetMaximumUTF8CStringSize(propertyName);
+	char buffer[maxSize];
+	JSStringGetUTF8CString(propertyName, buffer, maxSize);
+	std::string prop(buffer);
+	
+	return invokers.find(prop) != invokers.end();
+}
+
+JSValueRef JSCDataModel::jsInvokerGetProp(JSContextRef ctx, JSObjectRef object, JSStringRef propertyName, JSValueRef* exception) {
+	JSCDataModel* INSTANCE = (JSCDataModel*)JSObjectGetPrivate(object);
+	std::map<std::string, Invoker> invokers = INSTANCE->_interpreter->getInvokers();
+	
+	size_t maxSize = JSStringGetMaximumUTF8CStringSize(propertyName);
+	char buffer[maxSize];
+	JSStringGetUTF8CString(propertyName, buffer, maxSize);
+	std::string prop(buffer);
+	
+	if (invokers.find(prop) != invokers.end()) {
+		return INSTANCE->getDataAsValue(invokers.find(prop)->second.getDataModelVariables());
+	}
+	return JSValueMakeUndefined(ctx);
+}
+
+void JSCDataModel::jsInvokerListProps(JSContextRef ctx, JSObjectRef object, JSPropertyNameAccumulatorRef propertyNames) {
+	JSCDataModel* INSTANCE = (JSCDataModel*)JSObjectGetPrivate(object);
+	std::map<std::string, Invoker> invokers = INSTANCE->_interpreter->getInvokers();
+	
+	std::map<std::string, Invoker>::const_iterator invokerIter = invokers.begin();
+	while(invokerIter != invokers.end()) {
+		JSStringRef invokeName = JSStringCreateWithUTF8CString(invokerIter->first.c_str());
+		JSPropertyNameAccumulatorAddName(propertyNames, invokeName);
+		invokerIter++;
+	}	
+}
+
 }
\ No newline at end of file
diff --git a/src/uscxml/plugins/datamodel/ecmascript/JavaScriptCore/JSCDataModel.h b/src/uscxml/plugins/datamodel/ecmascript/JavaScriptCore/JSCDataModel.h
index 9f254e4..9e70a8f 100644
--- a/src/uscxml/plugins/datamodel/ecmascript/JavaScriptCore/JSCDataModel.h
+++ b/src/uscxml/plugins/datamodel/ecmascript/JavaScriptCore/JSCDataModel.h
@@ -71,7 +71,12 @@ protected:
 	static bool jsIOProcessorHasProp(JSContextRef ctx, JSObjectRef object, JSStringRef propertyName);
 	static JSValueRef jsIOProcessorGetProp(JSContextRef ctx, JSObjectRef object, JSStringRef propertyName, JSValueRef* exception);
 	static void jsIOProcessorListProps(JSContextRef ctx, JSObjectRef object, JSPropertyNameAccumulatorRef propertyNames);
-	
+
+	static JSClassDefinition jsInvokersClassDef;
+	static bool jsInvokerHasProp(JSContextRef ctx, JSObjectRef object, JSStringRef propertyName);
+	static JSValueRef jsInvokerGetProp(JSContextRef ctx, JSObjectRef object, JSStringRef propertyName, JSValueRef* exception);
+	static void jsInvokerListProps(JSContextRef ctx, JSObjectRef object, JSPropertyNameAccumulatorRef propertyNames);
+
 	JSValueRef getDocumentAsValue(const Arabica::DOM::Document<std::string>& doc);
 	JSValueRef getDataAsValue(const Data& data);
 	Data getValueAsData(const JSValueRef value);
diff --git a/src/uscxml/plugins/datamodel/prolog/swi/SWIDataModel.cpp b/src/uscxml/plugins/datamodel/prolog/swi/SWIDataModel.cpp
index 2f43c73..462b661 100644
--- a/src/uscxml/plugins/datamodel/prolog/swi/SWIDataModel.cpp
+++ b/src/uscxml/plugins/datamodel/prolog/swi/SWIDataModel.cpp
@@ -8,6 +8,21 @@
 #include <Pluma/Connector.hpp>
 #endif
 
+#define SET_PL_CONTEXT \
+_dmPtr = this;
+
+#define PL_MODULE \
+_interpreter.getSessionId().c_str() \
+
+#define UNSET_PL_ENGINE(dm) \
+PL_set_engine(NULL, NULL);
+
+#define SET_PL_ENGINE(dm) \
+assert(_swiEngines.find(dm) != _swiEngines.end()); \
+int rc = PL_set_engine(_swiEngines[dm], NULL); \
+assert(rc == PL_ENGINE_SET); \
+_dmPtr = dm;
+
 namespace uscxml {
 
 using namespace Arabica::XPath;
@@ -21,43 +36,90 @@ bool connect(pluma::Host& host) {
 }
 #endif
 
+// SWI prolog does not support passing user data
+static SWIDataModel* _dmPtr;
+static std::map<SWIDataModel*, PL_engine_t> _swiEngines;
+
 SWIDataModel::SWIDataModel() {
 }
 
-// SWI prolog does not support passing user data
-static InterpreterImpl* _swiInterpreterPtr;
-
+SWIDataModel::~SWIDataModel() {
+	if (_swiEngines.find(this) != _swiEngines.end()) {
+		PL_destroy_engine(_swiEngines[this]);
+		_swiEngines.erase(this);
+	}
+}
+	
 boost::shared_ptr<DataModelImpl> SWIDataModel::create(InterpreterImpl* interpreter) {
 	boost::shared_ptr<SWIDataModel> dm = boost::shared_ptr<SWIDataModel>(new SWIDataModel());
 	dm->_interpreter = interpreter;
 
-	// this is most unfortunate!
-	_swiInterpreterPtr = interpreter;
 	const char* swibin = getenv("SWI_BINARY");
 	if (swibin == NULL)
 		swibin = SWI_BINARY;
 	const char* quiet = "--quiet";
 
+	int argc = 2;
 	static char * av[] = {
 		(char*)swibin,
 		(char*)quiet,
-		//    "-s",
-		//    "/Users/sradomski/Documents/TK/Code/pl-devel/demo/likes.pl",
 		NULL
 	};
-	if(!PL_initialise(2,av)) {
-		LOG(ERROR) << "Error intializing prolog engine";
-		PL_halt(1);
-		return boost::shared_ptr<DataModelImpl>();
-	}
 
-	// load SWI XML parser
-	PlCall("use_module", PlCompound("library", PlTerm("sgml")));
+	PL_engine_t engine;
 
-	// load json parser
-	PlCall("use_module", PlCompound("library", PlTerm("http/json")));
-	PlCall("use_module", PlCompound("library", PlTerm("http/json_convert")));
+	if (!PL_is_initialised(NULL, NULL)) {
+		if(!PL_initialise(argc,av)) {
+			LOG(ERROR) << "Error intializing prolog engine";
+			PL_halt(1);
+			return boost::shared_ptr<DataModelImpl>();
+		} else {
+			LOG(WARNING) << "Instantiating more than one SWI prolog datamodel will lead to weird effects as I cannot seperate the environments";
+		}
+		
+		PL_set_engine(PL_ENGINE_CURRENT, &engine);
+		
+		// load SWI XML parser
+		try {
+			PlCall("use_module", PlCompound("library", PlTerm("sgml")));
+		} catch (PlException plex) {
+			
+			LOG(ERROR) << "Cannot load prolog sgml module - make sure you have it installed in your prolog runtime: " << (char*)plex;
+			throw plex;
+		}
+		
+		// load json parser
+		try {
+			PlCall("use_module", PlCompound("library", PlTerm("http/json")));
+			PlCall("use_module", PlCompound("library", PlTerm("http/json_convert")));
+		} catch (PlException plex) {
+			LOG(ERROR) << "Cannot load prolog json module or json_convert - make sure you have it installed in your prolog runtime: " << (char*)plex;
+			throw plex;
+		}
 
+	} else {
+		engine = PL_create_engine(NULL);
+	}
+		
+	assert(engine);
+	_swiEngines[dm.get()] = engine;	
+	_dmPtr = dm.get();
+	
+	int rc = PL_set_engine(engine, NULL);
+	assert(rc == PL_ENGINE_SET);
+
+	_plModule = boost::replace_all_copy(interpreter->getSessionId(), "-", "");
+	boost::replace_all(_plModule, "0", "g");
+	boost::replace_all(_plModule, "1", "h");
+	boost::replace_all(_plModule, "2", "i");
+	boost::replace_all(_plModule, "3", "j");
+	boost::replace_all(_plModule, "4", "k");
+	boost::replace_all(_plModule, "5", "l");
+	boost::replace_all(_plModule, "6", "m");
+	boost::replace_all(_plModule, "7", "n");
+	boost::replace_all(_plModule, "8", "o");
+	boost::replace_all(_plModule, "9", "p");
+		
 	// use atoms for double quoted
 	PlCall("set_prolog_flag(double_quotes,atom).");
 
@@ -89,7 +151,7 @@ boost::shared_ptr<DataModelImpl> SWIDataModel::create(InterpreterImpl* interpret
 foreign_t SWIDataModel::inPredicate(term_t a0, int arity, void* context) {
 	char *s;
 	if ( PL_get_atom_chars(a0, &s) ) {
-		NodeSet<std::string> config = _swiInterpreterPtr->getConfiguration();
+		NodeSet<std::string> config = _dmPtr->_interpreter->getConfiguration();
 		for (int i = 0; i < config.size(); i++) {
 			if (HAS_ATTR(config[i], "id") && strcmp(ATTR(config[i], "id").c_str(), s) == 0) {
 				return TRUE;
@@ -113,9 +175,6 @@ void SWIDataModel::setName(const std::string& name) {
 	_name = name;
 }
 
-SWIDataModel::~SWIDataModel() {
-}
-
 void SWIDataModel::pushContext() {
 //	std::cout << "SWIDataModel::pushContext" << std::endl;
 }
@@ -129,6 +188,7 @@ void SWIDataModel::initialize() {
 }
 
 void SWIDataModel::setEvent(const Event& event) {
+	SET_PL_CONTEXT;
 	// remove old event
 	try {
 		PlCall("retractall(event(_))");
@@ -208,17 +268,20 @@ void SWIDataModel::setEvent(const Event& event) {
 }
 
 Data SWIDataModel::getStringAsData(const std::string& content) {
+	SET_PL_CONTEXT
 //	std::cout << "SWIDataModel::getStringAsData" << std::endl;
 	Data data;
 	return data;
 }
 
 bool SWIDataModel::validate(const std::string& location, const std::string& schema) {
+	SET_PL_CONTEXT
 //	std::cout << "SWIDataModel::validate" << std::endl;
 	return true;
 }
 
 uint32_t SWIDataModel::getLength(const std::string& expr) {
+	SET_PL_CONTEXT
 	PlCompound compound(expr.c_str());
 	PlTermv termv(compound.arity());
 	for (int i = 0; i < compound.arity(); i++) {
@@ -235,6 +298,7 @@ void SWIDataModel::setForeach(const std::string& item,
                               const std::string& array,
                               const std::string& index,
                               uint32_t iteration) {
+	SET_PL_CONTEXT
 	PlCompound compound(array.c_str());
 	PlCompound orig(array.c_str());
 	PlTermv termv(compound.arity());
@@ -262,6 +326,7 @@ void SWIDataModel::setForeach(const std::string& item,
 }
 
 void SWIDataModel::eval(const Element<std::string>& scriptElem, const std::string& expr) {
+	SET_PL_CONTEXT
 	if (scriptElem && HAS_ATTR(scriptElem, "type") && boost::iequals(ATTR(scriptElem, "type"), "query")) {
 		evalAsBool(expr);
 	} else {
@@ -271,6 +336,7 @@ void SWIDataModel::eval(const Element<std::string>& scriptElem, const std::strin
 }
 
 bool SWIDataModel::evalAsBool(const std::string& expr) {
+	SET_PL_CONTEXT
 	try {
 		PlCompound compound(expr.c_str());
 		PlTermv termv(compound.arity());
@@ -285,6 +351,7 @@ bool SWIDataModel::evalAsBool(const std::string& expr) {
 }
 
 std::string SWIDataModel::evalAsString(const std::string& expr) {
+	SET_PL_CONTEXT
 	PlCompound orig(expr.c_str()); // keep the original to find variables
 	PlCompound compound(expr.c_str());
 	if (strlen(compound.name())) {
@@ -316,6 +383,7 @@ std::string SWIDataModel::evalAsString(const std::string& expr) {
 
 // this is similar to http://etalis.googlecode.com/svn/eEtalis/src/term.c
 std::map<std::string, PlTerm> SWIDataModel::resolveAtoms(PlTerm& term, PlTerm& orig) {
+	SET_PL_CONTEXT
 	std::map<std::string, PlTerm> atoms;
 	switch (orig.type()) {
 	case PL_VARIABLE: {
@@ -343,6 +411,7 @@ std::map<std::string, PlTerm> SWIDataModel::resolveAtoms(PlTerm& term, PlTerm& o
 void SWIDataModel::assign(const Element<std::string>& assignElem,
                           const Document<std::string>& doc,
                           const std::string& content) {
+	SET_PL_CONTEXT
 	std::string expr = content;
 	std::string predicate;
 	if (HAS_ATTR(assignElem, "expr")) {
diff --git a/src/uscxml/plugins/datamodel/prolog/swi/SWIDataModel.h b/src/uscxml/plugins/datamodel/prolog/swi/SWIDataModel.h
index f391139..b4532cf 100644
--- a/src/uscxml/plugins/datamodel/prolog/swi/SWIDataModel.h
+++ b/src/uscxml/plugins/datamodel/prolog/swi/SWIDataModel.h
@@ -66,8 +66,8 @@ protected:
 	std::map<std::string, PlTerm> resolveAtoms(PlTerm& term, PlTerm& orig);
 
 	Event _event;
-	PlEngine* _plEngine;
 
+	std::string _plModule;
 	std::string _name;
 	std::string _sessionId;
 };
diff --git a/src/uscxml/plugins/invoker/CMakeLists.txt b/src/uscxml/plugins/invoker/CMakeLists.txt
index e836275..67d356a 100644
--- a/src/uscxml/plugins/invoker/CMakeLists.txt
+++ b/src/uscxml/plugins/invoker/CMakeLists.txt
@@ -127,6 +127,26 @@ if (FFMPEG_FOUND)
 endif()
 
 
+# calendar invoker
+
+if (LIBICAL_FOUND)
+	file(GLOB_RECURSE CALENDAR_INVOKER
+		calendar/*.cpp
+		calendar/*.h
+	)
+	source_group("Invoker\\caledar" FILES ${CALENDAR_INVOKER})
+	if (BUILD_AS_PLUGINS)
+		add_library(
+			invoker_calendar SHARED 
+			${CALENDAR_INVOKER})
+		target_link_libraries(invoker_calendar uscxml)
+		set_target_properties(invoker_calendar PROPERTIES FOLDER "Plugin Invoker")
+	else()
+		list (APPEND USCXML_FILES ${CALENDAR_INVOKER})
+	endif()
+endif()
+
+
 # UMUNDO invoker 
 
 if (UMUNDO_FOUND)
diff --git a/src/uscxml/plugins/invoker/calendar/CalendarInvoker.cpp b/src/uscxml/plugins/invoker/calendar/CalendarInvoker.cpp
new file mode 100644
index 0000000..7ea3fc3
--- /dev/null
+++ b/src/uscxml/plugins/invoker/calendar/CalendarInvoker.cpp
@@ -0,0 +1,44 @@
+#include "CalendarInvoker.h"
+#include <glog/logging.h>
+
+#ifdef BUILD_AS_PLUGINS
+#include <Pluma/Connector.hpp>
+#endif
+
+namespace uscxml {
+
+#ifdef BUILD_AS_PLUGINS
+PLUMA_CONNECTOR
+bool connect(pluma::Host& host) {
+	host.add( new CalendarInvokerProvider() );
+	return true;
+}
+#endif
+
+CalendarInvoker::CalendarInvoker() {
+}
+
+CalendarInvoker::~CalendarInvoker() {
+};
+
+boost::shared_ptr<InvokerImpl> CalendarInvoker::create(InterpreterImpl* interpreter) {
+	boost::shared_ptr<CalendarInvoker> invoker = boost::shared_ptr<CalendarInvoker>(new CalendarInvoker());
+	invoker->_interpreter = interpreter;
+	return invoker;
+}
+
+Data CalendarInvoker::getDataModelVariables() {
+	Data data;
+	return data;
+}
+
+void CalendarInvoker::send(const SendRequest& req) {
+}
+
+void CalendarInvoker::cancel(const std::string sendId) {
+}
+
+void CalendarInvoker::invoke(const InvokeRequest& req) {
+}
+
+}
\ No newline at end of file
diff --git a/src/uscxml/plugins/invoker/calendar/CalendarInvoker.h b/src/uscxml/plugins/invoker/calendar/CalendarInvoker.h
new file mode 100644
index 0000000..45dc8d0
--- /dev/null
+++ b/src/uscxml/plugins/invoker/calendar/CalendarInvoker.h
@@ -0,0 +1,40 @@
+#ifndef CALENDARINVOKER_H_W09J90F0
+#define CALENDARINVOKER_H_W09J90F0
+
+#include <uscxml/Interpreter.h>
+
+#ifdef BUILD_AS_PLUGINS
+#include "uscxml/plugins/Plugins.h"
+#endif
+
+namespace uscxml {
+
+class CalendarInvoker : public InvokerImpl {
+public:
+	CalendarInvoker();
+	virtual ~CalendarInvoker();
+	virtual boost::shared_ptr<InvokerImpl> create(InterpreterImpl* interpreter);
+
+	virtual std::set<std::string> getNames() {
+		std::set<std::string> names;
+		names.insert("calendar");
+		names.insert("http://uscxml.tk.informatik.tu-darmstadt.de/#calendar");
+		return names;
+	}
+
+	virtual Data getDataModelVariables();
+	virtual void send(const SendRequest& req);
+	virtual void cancel(const std::string sendId);
+	virtual void invoke(const InvokeRequest& req);
+
+protected:
+};
+
+#ifdef BUILD_AS_PLUGINS
+PLUMA_INHERIT_PROVIDER(CalendarInvoker, InvokerImpl);
+#endif
+
+}
+
+
+#endif /* end of include guard: CALENDARINVOKER_H_W09J90F0 */
diff --git a/src/uscxml/server/HTTPServer.cpp b/src/uscxml/server/HTTPServer.cpp
index f4b1a57..7e1a858 100644
--- a/src/uscxml/server/HTTPServer.cpp
+++ b/src/uscxml/server/HTTPServer.cpp
@@ -346,7 +346,7 @@ bool HTTPServer::registerServlet(const std::string& path, HTTPServlet* servlet)
 
 	INSTANCE->_servlets[suffixedPath] = servlet;
 
-	LOG(INFO) << "HTTP Servlet listening at: " << servletURL.str() << std::endl;
+//	LOG(INFO) << "HTTP Servlet listening at: " << servletURL.str() << std::endl;
 
 	// register callback
 	evhttp_set_cb(INSTANCE->_http, ("/" + suffixedPath).c_str(), HTTPServer::httpRecvReqCallback, servlet);