How do I write enum classes within enum classes in C++?

I am writing part of a larger C++ program.

I want to write a header file, say, "Component.h", with code like this...

class Component{
    private:
        int value;
        ComponentType component_type;
        vector<Component> components_this_component_derives_from;
        ...
        ...
    protected:
        inline void setValue(int value) { this->value = value; }
        inline int getValue() { return value; }
        inline ComponentType getComponentType() { return component_type; }
        inline void setComponentType(ComponentType component_type) { this->component_type = component_type; }
    public:
        Component() { value = 0; }
        ~Component() {}
        void setupDependentComponents(vector<Component> dependentComponents){
            components_this_component_derives_from = dependentComponents;
        }
        virtual void setupParams(vector<string> &params) = 0;
        virtual void init() = 0; // This is where setComponentType() is called
        virtual bool isValid() = 0; // This is where dependent component types are checked and polymorphic behaviour of the component set up
        virtual void calculate(customDataType custom_data) = 0;
}

All "Components" required will inherit this as a parent class. Some components require a certain type of components to derive from, or behave differently depending on the type of components it is set to derive from. For example, I expect ComponentA to depend on one component. If it depends on Component B of ComponentType::TypeX, it will multiply this value by 2 and call setValue() with this. However if Component B is of ComponentType::TypeY, it will square this value and call setValue() with this.

I have achieved this much by writing the following...

enum class ComponentType{
    TypeX, TypeY, TypeZ
};

However now I need to divide each component type into subtypes. Something like...

enum class ComponentType{
    enum class{
        SubTypeA, SubTypeB
    }TypeX,
    enum class{
        SubTypeA, SubTypeC, SubTypeD
    }TypeY,
    TypeZ
};

I want to use if/switch statements on the Type itself, as well as the SubType, if needed, so I am not sure namespaces would work.

The kind of code I want to write with if statements would be like this...

if(ComponentP.getComponentType != ComponentType::TypeX){
    cerr << "Unexpected component type" << endl;
    abort();
}
if(ComponentP.getComponentType == ComponentType::TypeX::SubTypeA){
    ...
} else {
    ...
}

How do I do this?

Edit: Just writing a namespace in place of the outer enum is not useful because not all component types have a subtype, and also because I cannot write something like if(ComponentA.getComponentType() == ComponentType::TypeA) { ... } if TypeA is just a namespace.