Extensions: Introduce classes and port App groups

src/App/Extension.cpp

@@ -0,0 +1,111 @@
+/***************************************************************************
+ *   Copyright (c) Stefan Tröger          (stefantroeger@gmx.net) 2016     *
+ *                                                                         *
+ *   This file is part of the FreeCAD CAx development system.              *
+ *                                                                         *
+ *   This library is free software; you can redistribute it and/or         *
+ *   modify it under the terms of the GNU Library General Public           *
+ *   License as published by the Free Software Foundation; either          *
+ *   version 2 of the License, or (at your option) any later version.      *
+ *                                                                         *
+ *   This library  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 Library General Public License for more details.                  *
+ *                                                                         *
+ *   You should have received a copy of the GNU Library General Public     *
+ *   License along with this library; see the file COPYING.LIB. If not,    *
+ *   write to the Free Software Foundation, Inc., 59 Temple Place,         *
+ *   Suite 330, Boston, MA  02111-1307, USA                                *
+ *                                                                         *
+ ***************************************************************************/
+
+
+#include "PreCompiled.h"
+
+#ifndef _PreComp_
+# include <cassert>
+# include <algorithm>
+#endif
+
+#include "Extension.h"
+#include "DocumentObject.h"
+#include "Base/Exception.h"
+ 
+TYPESYSTEM_SOURCE(App::Extension, App::PropertyContainer);
+
+using namespace App;
+
+//**************************************************************************
+// Construction/Destruction
+
+// here the implemataion! description should take place in the header file!
+Extension::Extension() {}
+
+Extension::~Extension()
+{
+
+}
+
+void Extension::setExtendedObject(DocumentObject* obj) {
+
+    if(m_extensionType.isBad())
+        throw Base::Exception("Extension::setExtendedObject: Extension type not set");
+    
+    m_base = obj;
+    obj->registerExtension( m_extensionType, this );
+}
+
+
+
+TYPESYSTEM_SOURCE(App::ExtensionContainer, App::PropertyContainer);
+
+ExtensionContainer::ExtensionContainer() {
+
+};
+
+ExtensionContainer::~ExtensionContainer() {
+
+};
+
+void ExtensionContainer::registerExtension(Base::Type extension, Extension* ext) {
+
+    if(hasExtension(extension))
+        throw Base::Exception("ExtensionContainer::registerExtension: Such a extension is already registered");
+    
+    if(ext->getExtendedObject() != this)
+        throw Base::Exception("ExtensionContainer::registerExtension: Extension has not this as base object");
+    
+    _extensions[extension] = ext;
+}
+
+bool ExtensionContainer::hasExtension(Base::Type t) const {
+
+    //check for the exact type
+    bool found = _extensions.find(t) != _extensions.end();
+    if(!found) {
+        //and for types derived from it, as they can be cast to the extension
+        for(auto entry : _extensions) {            
+            if(entry.first.isDerivedFrom(t))
+                return true;
+        }
+        return false;
+    }
+    return true;
+}
+
+Extension* ExtensionContainer::getExtension(Base::Type t) {
+   
+    auto result = _extensions.find(t);
+    if(result == _extensions.end()) {
+        //we need to check for derived types
+        for(auto entry : _extensions) {            
+            if(entry.first.isDerivedFrom(t))
+                return entry.second;
+        }
+        //if we arive hear we don't have anything matching
+        throw Base::Exception("ExtensionContainer::getExtension: No extension of given type available");
+    }
+    
+    return result->second;
+}