Identify what is being dragged globally

I would like to implement the same kind of behavior as the Dropoverapp application, specifically being able to perform a specific action when files are dragged (such as opening a window, for example).

I have written the code below to capture the mouse coordinates, drag, drop, and click globally. However, I don't know how to determine the nature of what is being dropped. Do you have any ideas on how to detect the nature of what is being dragged outside the application's scope?

Here is my current code:

import SwiftUI
import CoreGraphics
 
struct ContentView: View {
    @State private var mouseX: CGFloat = 0.0
    @State private var mouseY: CGFloat = 0.0
    @State private var isClicked: Bool = false
    @State private var isDragging: Bool = false
 
    private var mouseTracker = MouseTracker.shared
 
    var body: some View {
        VStack {
            Text("Mouse coordinates: \(mouseX, specifier: "%.2f"), \(mouseY, specifier: "%.2f")")
                .padding()
            Text(isClicked ? "Mouse is clicked" : "Mouse is not clicked")
                .padding()
            Text(isDragging ? "Mouse is dragging" : "Mouse is not dragging")
                .padding()
        }
        .frame(width: 400, height: 200)
        .onAppear {
            mouseTracker.startTracking { newMouseX, newMouseY, newIsClicked, newIsDragging in
                self.mouseX = newMouseX
                self.mouseY = newMouseY
                self.isClicked = newIsClicked
                self.isDragging = newIsDragging
            }
        }
    }
}
 
class MouseTracker {
    static let shared = MouseTracker()
    private var eventTap: CFMachPort?
    private var runLoopSource: CFRunLoopSource?
    private var isClicked: Bool = false
    private var isDragging: Bool = false
    private var callback: ((CGFloat, CGFloat, Bool, Bool) -> Void)?
 
    func startTracking(callback: @escaping (CGFloat, CGFloat, Bool, Bool) -> Void) {
        self.callback = callback
 
        let mask: CGEventMask = (1 << CGEventType.mouseMoved.rawValue) |
                                (1 << CGEventType.leftMouseDown.rawValue) |
                                (1 << CGEventType.leftMouseUp.rawValue) |
                                (1 << CGEventType.leftMouseDragged.rawValue)
 
        // Pass 'self' via 'userInfo'
        let selfPointer = UnsafeMutableRawPointer(Unmanaged.passUnretained(self).toOpaque())
 
        guard let eventTap = CGEvent.tapCreate(
            tap: .cghidEventTap,
            place: .headInsertEventTap,
            options: .defaultTap,
            eventsOfInterest: mask,
            callback: MouseTracker.mouseEventCallback,
            userInfo: selfPointer
        ) else {
            print("Failed to create event tap")
            return
        }
 
        self.eventTap = eventTap
        runLoopSource = CFMachPortCreateRunLoopSource(kCFAllocatorDefault, eventTap, 0)
        CFRunLoopAddSource(CFRunLoopGetCurrent(), runLoopSource, .commonModes)
        CGEvent.tapEnable(tap: eventTap, enable: true)
    }
 
    // Static callback function
    private static let mouseEventCallback: CGEventTapCallBack = { _, eventType, event, userInfo in
        guard let userInfo = userInfo else {
            return Unmanaged.passUnretained(event)
        }
 
        // Retrieve the instance of MouseTracker from userInfo
        let tracker = Unmanaged<MouseTracker>.fromOpaque(userInfo).takeUnretainedValue()
 
        let location = NSEvent.mouseLocation
 
        // Update the click and drag state
        switch eventType {
        case .leftMouseDown:
            tracker.isClicked = true
            tracker.isDragging = false
        case .leftMouseUp:
            tracker.isClicked = false
            tracker.isDragging = false
        case .leftMouseDragged:
            tracker.isDragging = true
        default:
            break
        }
 
        // Call the callback on the main thread
        DispatchQueue.main.async {
            tracker.callback?(location.x, location.y, tracker.isClicked, tracker.isDragging)
        }
 
        return Unmanaged.passUnretained(event)
    }
}