element-ios/Riot/Modules/Room/EmojiPicker/EmojiPickerCoordinatorBridgePresenter.swift

/*
 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

@objc protocol EmojiPickerCoordinatorBridgePresenterDelegate {
    func emojiPickerCoordinatorBridgePresenter(_ coordinatorBridgePresenter: EmojiPickerCoordinatorBridgePresenter, didAddEmoji emoji: String, forEventId eventId: String)
    func emojiPickerCoordinatorBridgePresenter(_ coordinatorBridgePresenter: EmojiPickerCoordinatorBridgePresenter, didRemoveEmoji emoji: String, forEventId eventId: String)
    func emojiPickerCoordinatorBridgePresenterDidCancel(_ coordinatorBridgePresenter: EmojiPickerCoordinatorBridgePresenter)
}

/// EmojiPickerCoordinatorBridgePresenter enables to start EmojiPickerCoordinator from a view controller.
/// This bridge is used while waiting for global usage of coordinator pattern.
@objcMembers
final class EmojiPickerCoordinatorBridgePresenter: NSObject {
    
    // MARK: - Properties
    
    // MARK: Private
    
    private let session: MXSession
    private let roomId: String
    private let eventId: String
    private var coordinator: EmojiPickerCoordinator?
    
    // MARK: Public
    
    weak var delegate: EmojiPickerCoordinatorBridgePresenterDelegate?
    
    // MARK: - Setup
    
    init(session: MXSession, roomId: String, eventId: String) {
        self.session = session
        self.roomId = roomId
        self.eventId = eventId
        super.init()
    }
    
    // MARK: - Public
    
    func present(from viewController: UIViewController,
                 sourceView: UIView?,
                 sourceRect: CGRect,
                 animated: Bool) {
        let emojiPickerCoordinator = EmojiPickerCoordinator(session: self.session, roomId: self.roomId, eventId: self.eventId)
        emojiPickerCoordinator.delegate = self
        
        let emojiPickerPresentable = emojiPickerCoordinator.toPresentable()
        
        if let sourceView = sourceView {
            
            emojiPickerPresentable.modalPresentationStyle = .popover
            
            if let popoverPresentationController = emojiPickerPresentable.popoverPresentationController {
                popoverPresentationController.sourceView = sourceView
                
                let finalSourceRect: CGRect
                
                if sourceRect != CGRect.null {
                    finalSourceRect = sourceRect
                } else {
                    finalSourceRect = sourceView.bounds
                }
                
                popoverPresentationController.sourceRect = finalSourceRect
            }
        }
        
        viewController.present(emojiPickerPresentable, animated: animated, completion: nil)
        
        emojiPickerCoordinator.start()
        
        self.coordinator = emojiPickerCoordinator
    }
    
    func dismiss(animated: Bool, completion: (() -> Void)?) {
        guard let coordinator = self.coordinator else {
            return
        }
        coordinator.toPresentable().dismiss(animated: animated) {
            self.coordinator = nil
            
            if let completion = completion {
                completion()
            }
        }
    }
}

// MARK: - EmojiPickerCoordinatorDelegate
extension EmojiPickerCoordinatorBridgePresenter: EmojiPickerCoordinatorDelegate {
    
    func emojiPickerCoordinator(_ coordinator: EmojiPickerCoordinatorType, didAddEmoji emoji: String, forEventId eventId: String) {
        self.delegate?.emojiPickerCoordinatorBridgePresenter(self, didAddEmoji: emoji, forEventId: eventId)
    }
    
    func emojiPickerCoordinator(_ coordinator: EmojiPickerCoordinatorType, didRemoveEmoji emoji: String, forEventId eventId: String) {
        self.delegate?.emojiPickerCoordinatorBridgePresenter(self, didRemoveEmoji: emoji, forEventId: eventId)
    }
    
    func emojiPickerCoordinatorDidCancel(_ coordinator: EmojiPickerCoordinatorType) {
        self.delegate?.emojiPickerCoordinatorBridgePresenterDidCancel(self)
    }
}