//
//  ActionSheetDisappearAnimator.swift
//  PaiAi
//
//  Created by ffib on 2018/12/17.
//  Copyright © 2018 yb. All rights reserved.
//

import UIKit

class ActionSheetDisappearAnimator: NSObject {
    weak var delegate: AlertAnimatorDelegate?
    
    func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
        return 0.3
    }
    
    func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
        guard let fromVC = transitionContext.viewController(forKey: .from),
            let fromView = fromVC.view,
            let toVC = transitionContext.viewController(forKey: .to),
            let toView = toVC.view,
            let contentView = delegate?.getContentView() else { return }
        
        let duration = transitionDuration(using: transitionContext)
        
        let animation = CABasicAnimation(keyPath: "backgroundColor")
        animation.duration = duration
        animation.isRemovedOnCompletion = false
        animation.fillMode = kCAFillModeForwards
        animation.toValue = UIColor(red: 52 / 255,
                                    green: 52 / 255,
                                    blue: 52 / 255,
                                    alpha: 0).cgColor
        animation.fromValue = UIColor(red: 52 / 255,
                                      green: 52 / 255,
                                      blue: 52 / 255,
                                      alpha: 0.7).cgColor
        
        fromView.layer.add(animation, forKey: nil)
        
        
        let fromValue = contentView.layer.position.y
        let toValue = fromValue + contentView.bounds.height
        
        let contentAnimation = CABasicAnimation(keyPath: "position.y")
        
        contentAnimation.toValue = toValue
        contentAnimation.duration = duration
        contentAnimation.fromValue = fromValue
        contentAnimation.isRemovedOnCompletion = false
        contentAnimation.fillMode = kCAFillModeForwards
        
        contentView.layer.add(contentAnimation, forKey: nil)
        
        DispatchQueue.main.asyncAfter(deadline: DispatchTime.now() + duration) {
            let isCancelled = transitionContext.transitionWasCancelled
            transitionContext.completeTransition(!isCancelled)
            transitionContext.containerView.addSubview(toView)
            fromView.removeFromSuperview()
        }
    }
}