import UIKit
import RxSwift
import RxCocoa

let elementsPerSecond = 1
let delay: RxTimeInterval = .milliseconds(1500)

let sourceObservable = PublishSubject<Int>()

let sourceTimeline = TimelineView<Int>.make()
let delayedTimeline = TimelineView<Int>.make()

let stack = UIStackView.makeVertical([
  UILabel.makeTitle("delay"),
  UILabel.make("Emitted elements (\(elementsPerSecond) per sec.):"),
  sourceTimeline,
  UILabel.make("Delayed elements (with a \(delay)s delay):"),
  delayedTimeline])

var current = 1
let timer = DispatchSource.timer(interval: 1.0 / Double(elementsPerSecond), queue: .main) {
  sourceObservable.onNext(current)
  current = current + 1
}

_ = sourceObservable.subscribe(sourceTimeline)

// Setup the delayed subscription
_ = Observable<Int>
  .timer(.seconds(3), scheduler: MainScheduler.instance)
  .flatMap { _ in
    sourceObservable.delay(delay, scheduler: MainScheduler.instance)
}
.subscribe(delayedTimeline)

let hostView = setupHostView()
hostView.addSubview(stack)
hostView

// Support code -- DO NOT REMOVE
class TimelineView<E>: TimelineViewBase, ObserverType where E: CustomStringConvertible {
  static func make() -> TimelineView<E> {
    let view = TimelineView(frame: CGRect(x: 0, y: 0, width: 400, height: 100))
    view.setup()
    return view
  }
  public func on(_ event: Event<E>) {
    switch event {
    case .next(let value):
      add(.next(String(describing: value)))
    case .completed:
      add(.completed())
    case .error(_):
      add(.error())
    }
  }
}
/// Copyright (c) 2020 Razeware LLC
/// 
/// Permission is hereby granted, free of charge, to any person obtaining a copy
/// of this software and associated documentation files (the "Software"), to deal
/// in the Software without restriction, including without limitation the rights
/// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
/// copies of the Software, and to permit persons to whom the Software is
/// furnished to do so, subject to the following conditions:
/// 
/// The above copyright notice and this permission notice shall be included in
/// all copies or substantial portions of the Software.
/// 
/// Notwithstanding the foregoing, you may not use, copy, modify, merge, publish,
/// distribute, sublicense, create a derivative work, and/or sell copies of the
/// Software in any work that is designed, intended, or marketed for pedagogical or
/// instructional purposes related to programming, coding, application development,
/// or information technology.  Permission for such use, copying, modification,
/// merger, publication, distribution, sublicensing, creation of derivative works,
/// or sale is expressly withheld.
/// 
/// This project and source code may use libraries or frameworks that are
/// released under various Open-Source licenses. Use of those libraries and
/// frameworks are governed by their own individual licenses.
///
/// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
/// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
/// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
/// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
/// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
/// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
/// THE SOFTWARE.

