//
//  SheetContainerDismissAnimationController.swift
//  SheetImagePicker
//
//  Created by Shadowfacts on 9/24/19.
//  Copyright © 2019 Shadowfacts. All rights reserved.
//

import UIKit

class SheetContainerDismissAnimationController: NSObject, UIViewControllerAnimatedTransitioning {

    func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
        return 0.35
    }
    
    func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
        guard let fromVC = transitionContext.viewController(forKey: .from) as? SheetContainerViewController else {
            fatalError()
        }
        
        fromVC.view.alpha = 1.0
        fromVC.dimmingView.isHidden = true
        
        // match the frame to the original dimming view's frame so that it doesn't go under the content
        let dimmingView = UIView(frame: fromVC.dimmingView.bounds)
        dimmingView.backgroundColor = fromVC.dimmingView.backgroundColor
        dimmingView.alpha = fromVC.dimmingView.alpha

        let container = transitionContext.containerView
        container.addSubview(dimmingView)
        container.addSubview(fromVC.view)

        let duration = transitionDuration(using: transitionContext)
        UIView.animate(withDuration: duration, animations: {
            dimmingView.frame = container.bounds
            dimmingView.alpha = 0
            fromVC.view.transform = CGAffineTransform(translationX: 0, y: fromVC.content.view.bounds.height)
        }, completion: { (finished) in
            dimmingView.removeFromSuperview()

            transitionContext.completeTransition(!transitionContext.transitionWasCancelled)
        })
    }
    
}