Plug-in architecture

Plugin.swift

// Plugin type alias
typealias Plugin<T> = (T) -> T

// Plugin protocol for flexibility
protocol Pluginable {
    associatedtype T
    var plugins: [Plugin<T>] { get set }
    func applyPlugins(to value: T) -> T
}

extension Pluginable {
    func applyPlugins(to value: T) -> T {
        return plugins.reduce(value) { value, plugin in
            plugin(value)
        }
    }
}

// Example ViewModel
struct FirstViewModel {
    var title: String
}

// Example ViewController
class FirstVC: UIViewController, Pluginable {
    var viewModel: FirstViewModel
    var plugins: [Plugin<FirstViewModel>] = []

    required init(viewModel: FirstViewModel) {
        self.viewModel = viewModel
        super.init(nibName: nil, bundle: nil)
    }

    required init?(coder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
    
    override func viewDidLoad() {
        super.viewDidLoad()
        let updatedViewModel = applyPlugins(to: viewModel)
        // Update the UI based on the modified viewModel
    }
}

// Example Plugin
let capitalizeTitlePlugin: Plugin<FirstViewModel> = { viewModel in
    var newViewModel = viewModel
    newViewModel.title = newViewModel.title.uppercased()
    return newViewModel
}

let prefixTitlePlugin: Plugin<FirstViewModel> = { viewModel in
    var newViewModel = viewModel
    newViewModel.title = "Prefix: " + newViewModel.title
    return newViewModel
}

// Create an instance of FirstVC with plugins
let viewModel = FirstViewModel(title: "hello")
var firstVC = FirstVC(viewModel: viewModel)
firstVC.plugins = [capitalizeTitlePlugin, prefixTitlePlugin]