/*
 Copyright 2019 New Vector Ltd
 
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
 You may obtain a copy of the License at
 
 http://www.apache.org/licenses/LICENSE-2.0
 
 Unless required by applicable law or agreed to in writing, software
 distributed under the License is distributed on an "AS IS" BASIS,
 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 See the License for the specific language governing permissions and
 limitations under the License.
 */

import UIKit

/// `SlidingModalPresenter` allows to present a custom UIViewController or UIView conforming to `SlidingModalPresentable` as a modal with a vertical sliding animation from a UIViewController.
final class SlidingModalPresenter: NSObject {
    
    // MARK: - Constants
    
    private enum TabletContentSize {
        static let preferred = CGSize(width: 400.0, height: 400.0)
        static let minHeight: CGFloat = 0.0
        static let maxHeight: CGFloat = 600.0
    }
    
    // MARK: - Properties
    
    // swiftlint:disable weak_delegate
    private var transitionDelegate: SlidingModalPresentationDelegate?
    // swiftlint:enable weak_delegate
    private weak var presentingViewController: UIViewController?
    
    // MARK: - Public
    
    @objc func present(_ viewController: SlidingModalPresentable.ViewControllerType, from presentingViewController: UIViewController, animated: Bool, completion: (() -> Void)?) {
        
        if UIDevice.current.userInterfaceIdiom == .pad {
            viewController.modalPresentationStyle = .formSheet
            
            let preferredHeight = viewController.layoutHeightFittingWidth(TabletContentSize.preferred.width).clamped(to: TabletContentSize.minHeight...TabletContentSize.maxHeight)
            
            viewController.preferredContentSize = CGSize(width: TabletContentSize.preferred.width, height: preferredHeight)
        } else {
            let transitionDelegate = SlidingModalPresentationDelegate()
            
            viewController.modalPresentationStyle = .custom
            viewController.transitioningDelegate = transitionDelegate
            
            // Presented view controller does not affect the statusbar appearance
            viewController.modalPresentationCapturesStatusBarAppearance = false
            
            self.transitionDelegate = transitionDelegate
        }
        
        presentingViewController.present(viewController, animated: animated, completion: completion)
        
        self.presentingViewController = presentingViewController
    }
    
    @objc func presentView(_ view: SlidingModalPresentable.ViewType, from viewControllerPresenter: UIViewController, animated: Bool, completion: (() -> Void)?) {
        let viewController = SlidingModalEmptyViewController.instantiate(with: view)
        self.present(viewController, from: viewControllerPresenter, animated: animated, completion: completion)
    }
    
    @objc func dismiss(animated: Bool, completion: (() -> Void)?) {
        self.presentingViewController?.dismiss(animated: animated, completion: completion)
    }
}