MultiCastDelegate

MultiCastDelegate.swift

//
//  MulticastDelegate.swift
//  
//
//  Created by Tornike on 12.12.22.
//

import Foundation

final class MulticastDelegate<T> {
  private class DelegateWrapper {
    weak var delegate: AnyObject?

    init(_ delegate: AnyObject) {
      self.delegate = delegate
    }
  }

  // MARK: Instance Properties
  private var delegateWrappers: [DelegateWrapper]

  // swiftlint:disable force_cast
  var delegates: [T] {
    delegateWrappers = delegateWrappers.filter { $0.delegate != nil }
    return delegateWrappers.map { $0.delegate! } as! [T]
  }

  init(delegates: [T] = []) {
    delegateWrappers = delegates.map {
      DelegateWrapper($0 as AnyObject)
    }
  }

  // MARK: - Delegate Management
  func addDelegate(_ delegate: T) {
    let wrapper = DelegateWrapper(delegate as AnyObject)
    delegateWrappers.append(wrapper)
  }

  func removeDelegate(_ delegate: T) {
    guard let index = delegateWrappers.firstIndex(where: { $0.delegate === (delegate as AnyObject) }) else {
      return
    }
    delegateWrappers.remove(at: index)
  }

  func invokeDelegates(_ closure: (T) -> Void) {
    delegates.forEach { closure($0) }
  }
}