SwiftUI UIPageViewController wrapper with data source/lazy loading for Identifiable data

PageView.swift

import SwiftUI
import UIKit

struct PageView<Page: View, T: Identifiable>: UIViewControllerRepresentable {
    private class ModelViewController: UIHostingController<Page?> {
        var id: T.ID?
        
        init(id: T.ID?, rootView: Page?) {
            self.id = id
            super.init(rootView: rootView)
        }
        
        required init?(coder: NSCoder) {
            fatalError("init(coder:) has not been implemented")
        }
        
        override func viewDidLoad() {
            super.viewDidLoad()
            view.backgroundColor = .clear
        }
    }
    
    let data: [T]
    @Binding var currentID: T.ID?
    @ViewBuilder var pageBuilder: (T) -> Page
    
    func makeUIViewController(context: Context) -> UIPageViewController {
        let pageViewController = UIPageViewController(transitionStyle: .scroll, navigationOrientation: .horizontal)
        pageViewController.dataSource = context.coordinator
        pageViewController.delegate = context.coordinator
        let model = data.first(where: { $0.id == currentID })
        let hostingController = ModelViewController(id: currentID, rootView: model.map(pageBuilder))
        pageViewController.setViewControllers([hostingController], direction: .forward, animated: false)
        return pageViewController
    }
    
    func updateUIViewController(_ pageViewController: UIPageViewController, context: Context) {
        guard
            let oldViewController = pageViewController.viewControllers?.first as? ModelViewController,
            let oldIndex = data.firstIndex(where: { $0.id == oldViewController.id }),
            let newIndex = data.firstIndex(where: { $0.id == currentID })
        else { return }
        
        guard oldViewController.id != currentID else {
            oldViewController.rootView = pageBuilder(data[newIndex])
            return
        }

        let direction: UIPageViewController.NavigationDirection = (newIndex >= oldIndex) ? .forward : .reverse
        let hostingController = ModelViewController(id: currentID, rootView: pageBuilder(data[newIndex]))
        pageViewController.setViewControllers([hostingController], direction: direction, animated: true)
    }
    
    func makeCoordinator() -> Coordinator { Coordinator(parent: self) }
    
    class Coordinator: NSObject, UIPageViewControllerDataSource, UIPageViewControllerDelegate {
        var parent: PageView
        
        init(parent: PageView) {
            self.parent = parent
        }
        
        func pageViewController(
            _ pageViewController: UIPageViewController,
            viewControllerBefore viewController: UIViewController
        ) -> UIViewController? {
            guard
                let viewController = viewController as? ModelViewController,
                let index = parent.data.firstIndex(where: { $0.id == viewController.id }),
                index != 0
            else {
                return nil
            }
            let model = parent.data[index - 1]
            return ModelViewController(id: model.id, rootView: parent.pageBuilder(model))
        }
        
        func pageViewController(
            _ pageViewController: UIPageViewController,
            viewControllerAfter viewController: UIViewController
        ) -> UIViewController? {
            guard
                let viewController = viewController as? ModelViewController,
                let index = parent.data.firstIndex(where: { $0.id == viewController.id }),
                index + 1 != parent.data.count
            else {
                return nil
            }
            let model = parent.data[index + 1]
            return ModelViewController(id: model.id, rootView: parent.pageBuilder(model))
        }
        
        func pageViewController(
            _ pageViewController: UIPageViewController,
            didFinishAnimating finished: Bool,
            previousViewControllers: [UIViewController],
            transitionCompleted completed: Bool
        ) {
            guard
                completed,
                let currentViewController = pageViewController.viewControllers?.first as? ModelViewController
            else {
                return
            }
            parent.currentID = currentViewController.id
        }
    }
}