SwiftUI Window not draggable

Question

I made a custom AppDelegate which should remove the window toolbar and add a corner radius of 10px which all works very well hoeever now, you can't drag the window around.

I am also very new to AppKit and struggled to put this thing together with great help of Ai however I can't get it to work. Thanks in advance,

Here is my code:

import SwiftUI

@main
struct WindowTestApp: App {
    
    @NSApplicationDelegateAdaptor(AppDelegate.self) var appDelegate

    var body: some Scene {
        WindowGroup {
            ContentView()
                
        }
        .windowResizability(.contentSize)
    }
}

class AppDelegate: NSObject, NSApplicationDelegate {
    var window: NSWindow?

    func applicationDidFinishLaunching(_ notification: Notification) {
        window = NSApplication.shared.windows.first
        if let window = window {
            // Remove title bar and make window borderless
            window.styleMask = [.borderless, .resizable, .closable, .miniaturizable, .fullSizeContentView]
            window.isOpaque = false
            window.backgroundColor = NSColor.clear
            window.titleVisibility = .hidden
            window.titlebarAppearsTransparent = true

            // Set window corner radius
            window.contentView?.wantsLayer = true
            window.contentView?.layer?.cornerRadius = 10
            window.contentView?.layer?.masksToBounds = true
            
            // Add custom draggable view
            let draggableView = DraggableView(frame: window.contentView?.bounds ?? .zero)
            draggableView.autoresizingMask = [.width, .height]
            window.contentView?.addSubview(draggableView)
        }
    }
}

class DraggableView: NSView {
    private var initialLocation: NSPoint = .zero

    override func mouseDown(with event: NSEvent) {
        // Get the initial mouse location
        initialLocation = event.locationInWindow
    }

    override func mouseDragged(with event: NSEvent) {
        guard let window = self.window else { return }
        
        // Get the current mouse location
        let currentLocation = event.locationInWindow
        
        // Calculate the new origin for the window
        let deltaX = currentLocation.x - initialLocation.x
        let deltaY = currentLocation.y - initialLocation.y
        var newOrigin = window.frame.origin
        
        newOrigin.x += deltaX
        newOrigin.y += deltaY
        
        // Update the window's origin
        window.setFrameOrigin(newOrigin)
    }
}