CloseWindowEffect.swift

import AppKit
import Dependencies
import SwiftUI

@available(iOS 16.0, macOS 13.0, *)
@available(tvOS, unavailable)
@available(watchOS, unavailable)
private enum CloseWindowKey: DependencyKey {
   static let liveValue = CloseWindowEffect { id in
      Task { @MainActor in
         if let window = await NSWindow.find(windowId: id) {
            window.close()
         }
      }
   }

   static let testValue = CloseWindowEffect { _ in
      XCTFail(#"Unimplemented: @Dependency(\.closeWindow)"#)
   }
}

public struct CloseWindowEffect: Sendable {
   private let handler: @Sendable (String) async -> Void

   public init(handler: @escaping @Sendable (String) async -> Void) {
      self.handler = handler
   }

   public func callAsFunction<Window: Identifiable>(_ window: Window) async where Window.ID == String {
      await self.handler(window.id)
   }
}

extension DependencyValues {
   /// A dependency that closes a window.
   @available(iOS 16.0, macOS 13.0, *)
   @available(tvOS, unavailable)
   @available(watchOS, unavailable)
   public var closeWindow: CloseWindowEffect {
      get { self[CloseWindowKey.self] }
      set { self[CloseWindowKey.self] = newValue }
   }
}

extension NSWindow {
   public static func find(windowId: String) async -> NSWindow? {
      if let window = self.search(for: windowId) { return window }

      try? await Task.sleep(for: .milliseconds(50))
      if let window = self.search(for: windowId) { return window }

      try? await Task.sleep(for: .milliseconds(100))
      return self.search(for: windowId)
   }

   private static func search(for windowId: String) -> NSWindow? {
      NSApplication.shared.windows.first(where: { $0.identifier?.rawValue.contains(windowId) ?? false })
   }
}