WCF class library project to convert different message types like Json, Xml, HL7 (Mandatory)

Need a c# WCF class library project called "Interpreter" which converts the following, XML => Json Json => XML HL7 => Json HL7 => XML Json => HL7 XML => HL7 The project should comprise the following, ---Have implemented proper design pattern (should decide and inform before awarding) ---The incoming message formats should be first parsed before converting ---The outgoing message formats should be parsed before sending out to the client ---For conversion involving HL7, free third parties can be used (should decide and inform before awarding