Pass state through enum state

[JaapWijnen]

I have the following setup but I'm not sure how to pass part of the parent state on to my enum cases.
How can I make sure that changes to settings are still propagated whenever the .processing step part of the state is "active"

struct ParentState {
  var settings: SettingsState
  var step: Step 
  
  enum Step {
    case input(InputState)
    case processing(ProcessingState)
  }
}

struct InputState {
  // unique state for this object
}
struct ProcessingState {
  var settings: SettingsState
  // other unique state for this object
}

enum ParentAction {
  case input(InputAction)
  case processing(ProcessingAction)
}

My reducer:

let parentReducer = Reducer<ParentState, ParentAction, ParentEnvironment>.combine( 
  Reducer<ParentState.Step, ParentAction, ParentEnvironment>.combine(
    inputReducer.pullback(
      state: /ParentState.Step.input,
      action: /ParentAction.input,
      environment:  { ... }
    ),
    processingReducer.pullback(
      state: /ParentState.Step.processing,
      action: /ParentAction.processing,
      environment:  { ... }
    )
  ).pullback(
    state: \.step,
    action: /.self,
    environment: { $0 }
  ),
  Reducer<ParentState, ParentAction, ParentEnvironment> { state, action, env in 
    // parent reducer
    return .none
  }
)

EDIT:
Ah I think my problem is actually one step higher... I have the following AppState above the parent state.
So the problem is probably in this part as the settingsState has two instances when the state is in the .processing step

public struct AppState: Equatable {
    var settings: SettingsState
    var parentStep: ParentState.Step
    
    public init(settings: SettingsState = .init(), parentStep: ParentState.Step = .input(.init())) {
        self.settings = settings
        self.parentStep = parentStep
    }
    
    var parentState: parentState {
        get {
            ParentState(
                settings: self.settings,
                step: self.parentStep
            )
        }
        set {
            self.settings = newValue.settings
            self.parentStep = newValue.step
        }
    }
}

I'm still not quite sure how to remove the settings state from processing to make the state tree "pure" (no duplication) and then bolt it back on so that it's available in the ProcessingView/reducer logic etc.