ihealth_ios/Pods/IBAnimatable/Sources/Animators/Common/TransitionPresenter.swift

//
//  Created by Jake Lin on 2/24/16.
//  Copyright © 2016 IBAnimatable. All rights reserved.
//

import UIKit

/**
 TransitionPresenter for `UIViewController` to support custom transition animation for Present and Dismiss
 */
public class TransitionPresenter: NSObject {
  fileprivate var transitionAnimationType: TransitionAnimationType
  var transitionDuration: Duration {
    didSet {
      if oldValue != transitionDuration {
        updateTransitionDuration()
      }
    }
  }

  var interactiveGestureType: InteractiveGestureType? {
    // Update `interactiveAnimator` if needed
    didSet {
      if oldValue?.stringValue != interactiveGestureType?.stringValue {
        updateInteractiveAnimator()
      }
    }
  }

  // animation controller
  fileprivate var animator: AnimatedTransitioning?

  // interaction controller
  fileprivate var interactiveAnimator: InteractiveAnimator?

  public init(transitionAnimationType: TransitionAnimationType,
              transitionDuration: Duration = defaultTransitionDuration,
              interactiveGestureType: InteractiveGestureType? = nil) {
    self.transitionAnimationType = transitionAnimationType
    self.transitionDuration = transitionDuration
    super.init()

    updateTransitionDuration()
    animator = AnimatorFactory.makeAnimator(transitionAnimationType: transitionAnimationType, transitionDuration: transitionDuration)

    self.interactiveGestureType = interactiveGestureType
    updateInteractiveAnimator()
  }

  // MARK: - Private
  fileprivate func updateTransitionDuration() {
    if transitionDuration.isNaN {
      transitionDuration = defaultTransitionDuration
    }
  }

  fileprivate func updateInteractiveAnimator() {
    // If interactiveGestureType has been set
    if let interactiveGestureType = interactiveGestureType {
      // If configured as `.Default` then use the default interactive gesture type from the Animator
      switch interactiveGestureType {
      case .default:
        if let interactiveGestureType = animator?.interactiveGestureType {
          interactiveAnimator = InteractiveAnimatorFactory.makeInteractiveAnimator(interactiveGestureType: interactiveGestureType,
                                                                                   transitionType: .presentationTransition(.dismissal))
        }
      default:
        interactiveAnimator = InteractiveAnimatorFactory.makeInteractiveAnimator(interactiveGestureType: interactiveGestureType,
                                                                                 transitionType: .presentationTransition(.dismissal))
      }
    } else {
      interactiveAnimator = nil
    }
  }
}

extension TransitionPresenter: UIViewControllerTransitioningDelegate {

  // MARK: - animation controller
  public func animationController(forPresented presented: UIViewController,
                                  presenting: UIViewController,
                                  source: UIViewController) -> UIViewControllerAnimatedTransitioning? {
    animator?.transitionDuration = transitionDuration
    interactiveAnimator?.connectGestureRecognizer(to: presented)
    return animator
  }

  public func animationController(forDismissed dismissed: UIViewController) -> UIViewControllerAnimatedTransitioning? {
    // Use the reverse animation
    if let reverseTransitionAnimationType = animator?.reverseAnimationType {
      return AnimatorFactory.makeAnimator(transitionAnimationType: reverseTransitionAnimationType, transitionDuration: transitionDuration)
    }
    return nil
  }

  // MARK: - interaction controller
  public func interactionControllerForDismissal(using animator: UIViewControllerAnimatedTransitioning) -> UIViewControllerInteractiveTransitioning? {
    if let interactiveAnimator = interactiveAnimator, interactiveAnimator.interacting {
      return interactiveAnimator
    } else {
      return nil
    }
  }
}