element-ios/Riot/Modules/MajorUpdate/MajorUpdateViewController.swift

// File created from ScreenTemplate
// $ createScreen.sh SecretsSetupRecoveryKey SecretsSetupRecoveryKey
/*
 Copyright 2020 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

@objc
final class MajorUpdateViewController: UIViewController {
    
    // MARK: - Constants
    
    private enum Sizing {
        static var viewController: MajorUpdateViewController?
        static var widthConstraint: NSLayoutConstraint?
    }
    
    // MARK: - Properties
    
    // MARK: Outlets
    
    @IBOutlet private weak var scrollView: UIScrollView!
    
    @IBOutlet private weak var oldLogoImageView: UIImageView!
    @IBOutlet private weak var disclosureImageView: UIImageView!
    @IBOutlet private weak var newLogoImageView: UIImageView!
    
    @IBOutlet private weak var titleLabel: UILabel!
    @IBOutlet private weak var informationLabel: UILabel!
    @IBOutlet private weak var learnMoreButton: RoundedButton!
    @IBOutlet private weak var doneButton: UIButton!
    
    // MARK: Private
 
    private var theme: Theme!
    
    // MARK: Public
    
    @objc var didTapLearnMoreButton: (() -> Void)?
    @objc var didTapDoneButton: (() -> Void)?

    // MARK: - Setup
    
    @objc class func instantiate() -> MajorUpdateViewController {
        let viewController = StoryboardScene.MajorUpdateViewController.initialScene.instantiate()
        viewController.theme = ThemeService.shared().theme
        return viewController
    }
    
    // MARK: - Life cycle
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // Do any additional setup after loading the view.
        
        self.setupViews()
        
        self.registerThemeServiceDidChangeThemeNotification()
        self.update(theme: self.theme)
    }
    
    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        
        // Hide back button
        self.navigationItem.setHidesBackButton(true, animated: animated)
    }
    
    override var preferredStatusBarStyle: UIStatusBarStyle {
        return self.theme.statusBarStyle
    }
    
    // MARK: - Private
    
    private func update(theme: Theme) {
        self.theme = theme
        
        self.view.backgroundColor = theme.headerBackgroundColor
        
        if let navigationBar = self.navigationController?.navigationBar {
            theme.applyStyle(onNavigationBar: navigationBar)
        }
                
        self.disclosureImageView.tintColor = theme.noticeSecondaryColor
                
        self.newLogoImageView.tintColor = theme.tintColor
                
        self.titleLabel.textColor = theme.textPrimaryColor
        self.informationLabel.textColor = theme.textSecondaryColor
        
        self.learnMoreButton.update(theme: theme)
        theme.applyStyle(onButton: self.doneButton)
    }
    
    private func registerThemeServiceDidChangeThemeNotification() {
        NotificationCenter.default.addObserver(self, selector: #selector(themeDidChange), name: .themeServiceDidChangeTheme, object: nil)
    }
    
    @objc private func themeDidChange() {
        self.update(theme: ThemeService.shared().theme)
    }
    
    private func setupViews() {
        self.vc_removeBackTitle()
        
        self.oldLogoImageView.image = Asset.Images.oldLogo.image
        self.disclosureImageView.image = Asset.Images.disclosureIcon.image
        self.newLogoImageView.image = Asset.Images.launchScreenLogo.image
        
        self.titleLabel.text = VectorL10n.majorUpdateTitle
        self.informationLabel.text = VectorL10n.majorUpdateInformation
        
        self.learnMoreButton.setTitle(VectorL10n.majorUpdateLearnMoreAction, for: .normal)
        self.doneButton.setTitle(VectorL10n.majorUpdateDoneAction, for: .normal)
    }
    
    // MARK: - Actions

    @IBAction private func learnMoreButtonAction(_ sender: Any) {
        self.didTapLearnMoreButton?()
    }
    
    @IBAction private func doneButtonAction(_ sender: Any) {
        self.didTapDoneButton?()
    }
}

// MARK: - SlidingModalPresentable
extension MajorUpdateViewController: SlidingModalPresentable {
    
    func allowsDismissOnBackgroundTap() -> Bool {
        return true
    }
    
    func layoutHeightFittingWidth(_ width: CGFloat) -> CGFloat {
        
        let sizingViewContoller: MajorUpdateViewController
        
        if let viewController = MajorUpdateViewController.Sizing.viewController {
            sizingViewContoller = viewController
        } else {
            sizingViewContoller = MajorUpdateViewController.instantiate()
            MajorUpdateViewController.Sizing.viewController = sizingViewContoller
        }
        
        let sizingViewContollerView: UIView = sizingViewContoller.view
        
        if let widthConstraint = MajorUpdateViewController.Sizing.widthConstraint {
            widthConstraint.constant = width
        } else {
            let widthConstraint = sizingViewContollerView.widthAnchor.constraint(equalToConstant: width)
            widthConstraint.isActive = true
            MajorUpdateViewController.Sizing.widthConstraint = widthConstraint

            sizingViewContollerView.heightAnchor.constraint(equalToConstant: 0)
        }
        
        sizingViewContollerView.layoutIfNeeded()
        
        return sizingViewContoller.scrollView.contentSize.height
    }
}