Observes current running applications through `NSWorkspace` and notifies if any of the requested applications change their running status

RunningApplicationsObserver.swift

import AppKit
import Combine
import CombineExt
import Foundation
import SharedUtils

// sourcery: Automockable
protocol RunningApplicationsObserverType {
    func observeApplicationsRunningStatus(bundleIdentifiers: [String]) -> AnyPublisher<Void, Never>
}

///
/// Observes current running applications through `NSWorkspace` and notifies if any of the requested applications change their running
/// status
///
public class RunningApplicationsObserver: RunningApplicationsObserverType {

    let workspace: Workspace

    init(workspace: Workspace = WorkspaceManagement()) {
        self.workspace = workspace
    }

    // MARK: - RunningApplicationsObserverType

    func observeApplicationsRunningStatus(bundleIdentifiers: [String]) -> AnyPublisher<Void, Never> {
        AnyPublisher.create { subscriber in
            var disposeBag = Set<AnyCancellable>()
            let publishers = self.triggerNotifications.map { self.workspace.notificationCenter.publisher(for: $0) }
            Publishers.MergeMany(publishers)
                .filter { notification in
                    guard let application = notification.userInfo?[NSWorkspace.applicationUserInfoKey] as? NSRunningApplication,
                          let bundleIdentifier = application.bundleIdentifier,
                          bundleIdentifiers.contains(bundleIdentifier)
                    else {
                        return false
                    }
                    return true
                }
                .receive(on: DispatchQueue.main)
                .sink { _ in
                    subscriber.send(())
                }
                .store(in: &disposeBag)

            return AnyCancellable {
                disposeBag.removeAll()
            }
        }
    }

    private let triggerNotifications: [NSNotification.Name] = [
        NSWorkspace.didLaunchApplicationNotification,
        NSWorkspace.didTerminateApplicationNotification
    ]
}