/*
Copyright 2019-2024 New Vector Ltd.

SPDX-License-Identifier: AGPL-3.0-only
Please see LICENSE in the repository root for full details.
 */

import UIKit

/// `SlidingModalPresentationController` handles sliding transition presentation life cycle.
final class SlidingModalPresentationController: UIPresentationController {
    
    // MARK: - Properties
    
    private var slidingModalContainerView: SlidingModalContainerView? {
        return self.containerView?.subviews.first(where: { (view) -> Bool in
            view is SlidingModalContainerView
        }) as? SlidingModalContainerView
    }
    
    // MARK: - Setup
    
    override init(presentedViewController: UIViewController, presenting presentingViewController: UIViewController?) {
        super.init(presentedViewController: presentedViewController, presenting: presentingViewController)
    }
    
    // MARK: - Life cycle
    
    override func viewWillTransition(to size: CGSize, with coordinator: UIViewControllerTransitionCoordinator) {
        super.viewWillTransition(to: size, with: coordinator)
        
        if let slidingModalPresentable = self.presentedViewController as? SlidingModalPresentable, let slidingModalContainerView = self.slidingModalContainerView {
            
            let slidingModalContainerViewContentViewWidth = slidingModalContainerView.contentViewWidthFittingSize(size)
            
            let presentableHeight = slidingModalPresentable.layoutHeightFittingWidth(slidingModalContainerViewContentViewWidth)
            slidingModalContainerView.updateContentViewMaxHeight(presentableHeight)
        }
        
        coordinator.animate(alongsideTransition: { (UIViewControllerTransitionCoordinatorContext) -> Void in
            self.slidingModalContainerView?.updateContentViewLayout()
        }, completion: { _ in
            
        })
    }
    
    override func presentationTransitionWillBegin() {
        guard let coordinator = presentedViewController.transitionCoordinator else {
            return
        }
        
        coordinator.animate(alongsideTransition: { [weak self] _ in
            // Update status bar appearance of presented view controller (if presenting view controller allowed it, see `modalPresentationCapturesStatusBarAppearance` property)
            self?.presentedViewController.setNeedsStatusBarAppearanceUpdate()
        }, completion: nil)
    }
    
    override func presentationTransitionDidEnd(_ completed: Bool) {
        self.slidingModalContainerView?.delegate = self
    }
    
    override func dismissalTransitionWillBegin() {
        guard let coordinator = presentedViewController.transitionCoordinator else {
            return
        }

        coordinator.animate(alongsideTransition: { [weak self] _ -> Void in
            // Update status bar appearance of presenting view controller
            self?.presentingViewController.setNeedsStatusBarAppearanceUpdate()
        }, completion: nil)
    }
    
    override func dismissalTransitionDidEnd(_ completed: Bool) {
        if completed {
            self.slidingModalContainerView?.removeFromSuperview()
        }
    }
}

// MARK: - SlidingModalContainerViewDelegate
extension SlidingModalPresentationController: SlidingModalContainerViewDelegate {
    
    func slidingModalContainerViewDidTapBackground(_ view: SlidingModalContainerView) {
        
        let isDismissOnBackgroundTapAllowed: Bool
        
        if let slidingModalPresentable = self.presentedViewController as? SlidingModalPresentable {
            isDismissOnBackgroundTapAllowed = slidingModalPresentable.allowsDismissOnBackgroundTap()
        } else {
            isDismissOnBackgroundTapAllowed = true
        }
        
        if isDismissOnBackgroundTapAllowed {
            self.presentedViewController.dismiss(animated: true, completion: nil)
        }
    }
}