//
//  FFPresentationController.swift
//  FFAlert
//
//  Created by FFIB on 2017/11/13.
//  Copyright © 2017年 FFIB. All rights reserved.
//

import UIKit

class FFPresentationController: UIPresentationController {

    private let dimmingView = UIView()

    override init(presentedViewController: UIViewController, presenting presentingViewController: UIViewController?) {
        super.init(presentedViewController: presentedViewController, presenting: presentingViewController)
        dimmingView.backgroundColor = UIColor(white: 0, alpha: 0.4)
    }

    override func presentationTransitionWillBegin() {
        super.presentationTransitionWillBegin()

        presentingViewController.view.tintAdjustmentMode = .dimmed
        dimmingView.alpha = 0

        containerView?.addSubview(dimmingView)

        let coordinator = presentedViewController.transitionCoordinator
        coordinator?.animate(alongsideTransition: { _ in self.dimmingView.alpha = 1 }, completion: nil)
    }

    override func dismissalTransitionWillBegin() {
        super.dismissalTransitionWillBegin()

        presentingViewController.view.tintAdjustmentMode = .automatic

        let coordinator = presentedViewController.transitionCoordinator
        coordinator?.animate(alongsideTransition: { _ in self.dimmingView.alpha = 0 }, completion: nil)
    }

    override func containerViewWillLayoutSubviews() {
        super.containerViewWillLayoutSubviews()

        if let containerView = containerView {
            dimmingView.frame = containerView.frame
        }
    }
}