Libclang get class name from DeclRefExpr

Hi guys,

I am trying to extract the class name of a parameter to a method call in objective-C. The code I am parsing is:

- (void)testAddConcreteDataModel:(DFDemoDataModelOne*)helpmeh {
     [self.dataModels addObject:helpmeh];
And the result I need is the type of class of helpmeh, which is "DFDemoDataModelOne".

So far I have the following code, which outputs: "[(DFDataModelContainer).dataModels addObject:helpmeh]"

     if (cursor.kind == CXCursor_ObjCMessageExpr) {
         __block NSString* memberName = nil;
         __block NSString* ownerClassName = nil;
         __block NSString* methodName = [NSString stringWithUTF8String:clang_getCString(clang_getCursorDisplayName(cursor))];

         clang_visitChildrenWithBlock(cursor, ^enum CXChildVisitResult(CXCursor cursor, CXCursor parent) {
             if (cursor.kind == CXCursor_MemberRefExpr) {
                 memberName = [NSString stringWithUTF8String:clang_getCString(clang_getCursorDisplayName(cursor))];
                 ownerClassName = [NSString stringWithUTF8String:clang_getCString(clang_getCursorDisplayName(clang_getCursorSemanticParent(clang_getCursorReferenced(cursor))))];
             } else {
                 if (memberName) {
                     NSString* param = [NSString stringWithUTF8String:clang_getCString(clang_getCursorDisplayName(cursor))];
                     NSLog(@"[(%@).%@ %@%@]", ownerClassName, memberName, methodName, param);
                     clang_visitChildrenWithBlock(cursor, ^enum CXChildVisitResult(CXCursor cursor, CXCursor parent) {

                          // test
                          if ([param isEqualToString:@"helpmeh"] && cursor.kind == CXCursor_DeclRefExpr) {
                             // found the interesting part.. what now?
                          return CXChildVisit_Recurse;
             return CXChildVisit_Continue;
I'm just a bit lost as to how to extract information from cursors- when I AST dump my class I can see the information I need is all there (see the last line):

-ObjCMethodDecl 0x112790f90 <line:32:1, line:34:1> -

testAddConcreteDataModel: 'void'
   > >-ImplicitParamDecl 0x112791960 <<invalid sloc>> self 'DFDataModelContainer *const __strong'
   > >-ImplicitParamDecl 0x1127919c0 <<invalid sloc>> _cmd 'SEL':'SEL *'
   > >-ParmVarDecl 0x112791040 <line:32:35, col:55> helpmeh 'DFDemoDataModelOne *__strong'
   > `-CompoundStmt 0x112791bf0 <col:63, line:34:1>
   > `-ExprWithCleanups 0x112791bd8 <line:33:5, col:39> 'void'
   > `-ObjCMessageExpr 0x112791ba0 <col:5, col:39> 'void' selector=addObject:
   > >-PseudoObjectExpr 0x112791b48 <col:6, col:11> 'NSMutableArray *'
   > > >-ObjCPropertyRefExpr 0x112791ad0 <col:6, col:11> '<pseudo-object type>' lvalue objcproperty Kind=PropertyRef Property="dataModels" Messaging=Getter
   > > > `-OpaqueValueExpr 0x112791ab0 <col:6> 'DFDataModelContainer *'
   > > > `-ImplicitCastExpr 0x112791a40 <col:6> 'DFDataModelContainer *' <LValueToRValue>
   > > > `-DeclRefExpr 0x112791a18 <col:6> 'DFDataModelContainer *const __strong' lvalue ImplicitParam 0x112791960 'self' 'DFDataModelContainer *const __strong'
   > > >-OpaqueValueExpr 0x112791ab0 <col:6> 'DFDataModelContainer *'
   > > > `-ImplicitCastExpr 0x112791a40 <col:6> 'DFDataModelContainer *' <LValueToRValue>
   > > > `-DeclRefExpr 0x112791a18 <col:6> 'DFDataModelContainer *const __strong' lvalue ImplicitParam 0x112791960 'self' 'DFDataModelContainer *const __strong'
   > > `-ImplicitCastExpr 0x112791b30 <col:11> 'NSMutableArray *' <ARCReclaimReturnedObject>
   > > `-ObjCMessageExpr 0x112791b00 <col:11> 'NSMutableArray *' selector=dataModels
   > > `-OpaqueValueExpr 0x112791ab0 <col:6> 'DFDataModelContainer *'
   > > `-ImplicitCastExpr 0x112791a40 <col:6> 'DFDataModelContainer *' <LValueToRValue>
   > > `-DeclRefExpr 0x112791a18 <col:6> 'DFDataModelContainer *const __strong' lvalue ImplicitParam 0x112791960 'self' 'DFDataModelContainer *const __strong'
   > `-ImplicitCastExpr 0x112791b88 <col:32> 'id':'id' <BitCast>
   > `-ImplicitCastExpr 0x112791b70 <col:32> 'DFDemoDataModelOne *' <LValueToRValue>
   > `-DeclRefExpr 0x112791a88 <col:32> 'DFDemoDataModelOne *__strong' lvalue ParmVar 0x112791040 'helpmeh' 'DFDemoDataModelOne *__strong'

I have tried grabbing the semantic parent of the DeclRefExpr but the cursor kind is CXCursor_FirstInvalid. Now I'm stuck!

Any help appreciated,