swiftui get height of text and get the top unsafe height with grace

geometry reader.swift

struct SizePreferenceKey: PreferenceKey {
    typealias Value = CGSize?
    
    static func reduce(value: inout CGSize?, nextValue: () -> CGSize?) {
        value = value ?? nextValue()
    }
}

struct ReportSize: View {
    var base: Text
    var callBack: (CGSize?) -> ()
    
    var body: some View {
        base
            .background(GeometryReader { proxy in
                Color.clear.preference(key: SizePreferenceKey.self, value: proxy.size)
            }).onPreferenceChange(SizePreferenceKey.self, perform: { size in
                self.callBack(size)
            })
    }
}

extension Text {
    func reportSize(_ callBack: @escaping (CGSize?) -> Void) -> some View {
        ReportSize(base: self, callBack: callBack)
    }
}

struct ReportTopUnsafeHeight: View {
    
    var base: Color
    var callback: (CGFloat) -> ()
    
    @State var withEdge: CGFloat? {
        didSet {
            sendCallback()
        }
    }
    
    @State var withoutEdge: CGFloat? {
        didSet {
            sendCallback()
        }
    }
    
    func sendCallback() {
        if let bigger = withEdge, let smaller = withoutEdge {
            callback(bigger - smaller)
        }
    }
    
    var body: some View {
        GeometryReader { proxy in
            ZStack {
                VStack {
                    Color.clear.overlay(GeometryReader { proxy in
                        Color.clear.preference(key: SizePreferenceKey.self, value: proxy.size)
                    }).onPreferenceChange(SizePreferenceKey.self, perform: { value in
                        self.withEdge = value?.height
                    })
                }.edgesIgnoringSafeArea(.top)
                VStack {
                    Color.clear.overlay(GeometryReader { proxy in
                        Color.clear.preference(key: SizePreferenceKey.self, value: proxy.size)
                    }).onPreferenceChange(SizePreferenceKey.self, perform: { value in
                        self.withoutEdge = value?.height
                    })
                }
            }
        }
    }
}

extension Color {
    func reportTopUnsafeHeight(_ callback: @escaping (CGFloat) -> ()) -> some View {
        ReportTopUnsafeHeight(base: self, callback: callback)
    }
}