Reaction history: Implement screen.

Riot/Modules/Room/ReactionHistory/ReactionHistoryViewController.swift

@@ -0,0 +1,206 @@
+// File created from ScreenTemplate
+// $ createScreen.sh ReactionHistory ReactionHistory
+/*
+ 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
+
+final class ReactionHistoryViewController: UIViewController {
+    
+    // MARK: - Constants
+    
+    private enum TableView {
+        static let estimatedRowHeight: CGFloat = 21.0
+        static let contentInset = UIEdgeInsets(top: 10.0, left: 0.0, bottom: 10.0, right: 0.0)
+    }
+    
+    // MARK: - Properties
+    
+    // MARK: Outlets
+
+    @IBOutlet private weak var tableView: UITableView!
+    
+    // MARK: Private
+
+    private var viewModel: ReactionHistoryViewModelType!
+    private var theme: Theme!
+    private var errorPresenter: MXKErrorPresentation!
+    private var activityPresenter: ActivityIndicatorPresenter!
+    private var isViewAppearedOnce: Bool = false
+    
+    private var reactionHistoryViewDataList: [ReactionHistoryViewData] = []
+    
+
+    // MARK: - Setup
+    
+    class func instantiate(with viewModel: ReactionHistoryViewModelType) -> ReactionHistoryViewController {
+        let viewController = StoryboardScene.ReactionHistoryViewController.initialScene.instantiate()
+        viewController.viewModel = viewModel
+        viewController.theme = ThemeService.shared().theme
+        return viewController
+    }
+    
+    // MARK: - Life cycle
+    
+    override func viewDidLoad() {
+        super.viewDidLoad()
+        
+        // Do any additional setup after loading the view.
+        
+        self.title = VectorL10n.reactionHistoryTitle
+        
+        self.viewModel.viewDelegate = self
+        
+        self.activityPresenter = ActivityIndicatorPresenter()
+        self.errorPresenter = MXKErrorAlertPresentation()
+        
+        self.setupViews()
+        
+        self.registerThemeServiceDidChangeThemeNotification()
+        self.update(theme: self.theme)
+        
+        self.viewModel.process(viewAction: .loadMore)
+    }
+    
+    override func viewDidAppear(_ animated: Bool) {
+        super.viewDidAppear(animated)
+        
+        if self.isViewAppearedOnce == false {
+            self.isViewAppearedOnce = true
+        }
+    }
+    
+    override var preferredStatusBarStyle: UIStatusBarStyle {
+        return self.theme.statusBarStyle
+    }
+    
+    // MARK: - Private
+    
+    private func update(theme: Theme) {
+        self.theme = theme
+        
+        self.view.backgroundColor = theme.headerBackgroundColor
+        self.tableView.backgroundColor = theme.backgroundColor
+        
+        if let navigationBar = self.navigationController?.navigationBar {
+            theme.applyStyle(onNavigationBar: navigationBar)
+        }
+    }
+    
+    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 setupTableView() {
+        self.tableView.contentInset = TableView.contentInset
+        
+        self.tableView.rowHeight = UITableView.automaticDimension
+        self.tableView.estimatedRowHeight = TableView.estimatedRowHeight
+        self.tableView.register(cellType: ReactionHistoryViewCell.self)
+        
+        self.tableView.tableFooterView = UIView()
+    }
+    
+    private func setupViews() {
+        let closeBarButtonItem = MXKBarButtonItem(title: VectorL10n.close, style: .plain) { [weak self] in
+            self?.closeButtonAction()
+        }
+        
+        self.navigationItem.rightBarButtonItem = closeBarButtonItem
+        
+        self.setupTableView()
+    }
+
+    private func render(viewState: ReactionHistoryViewState) {
+        switch viewState {
+        case .loading:
+            self.renderLoading()
+        case .loaded(reactionHistoryViewDataList: let reactionHistoryViewDataList, allDataLoaded: let allDataLoaded):
+            self.renderLoaded(reactionHistoryViewDataList: reactionHistoryViewDataList, allDataLoaded: allDataLoaded)
+        case .error(let error):
+            self.render(error: error)
+        }
+    }
+    
+    private func renderLoading() {
+        self.activityPresenter.presentActivityIndicator(on: self.view, animated: true)
+    }
+    
+    private func renderLoaded(reactionHistoryViewDataList: [ReactionHistoryViewData], allDataLoaded: Bool) {
+        self.activityPresenter.removeCurrentActivityIndicator(animated: true)
+        self.reactionHistoryViewDataList = reactionHistoryViewDataList
+        self.tableView.reloadData()
+    }
+    
+    private func render(error: Error) {
+        self.activityPresenter.removeCurrentActivityIndicator(animated: true)
+        self.errorPresenter.presentError(from: self, forError: error, animated: true, handler: nil)
+    }
+    
+    // MARK: - Actions
+
+    private func closeButtonAction() {
+        self.viewModel.process(viewAction: .close)
+    }
+}
+
+// MARK: - UITableViewDataSource
+extension ReactionHistoryViewController: UITableViewDataSource {
+    
+    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
+        return self.reactionHistoryViewDataList.count
+    }
+    
+    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
+        let reactionHistoryCell = tableView.dequeueReusableCell(for: indexPath, cellType: ReactionHistoryViewCell.self)
+
+        let reactionHistoryViewData = self.reactionHistoryViewDataList[indexPath.row]
+
+        reactionHistoryCell.update(theme: self.theme)
+        reactionHistoryCell.fill(with: reactionHistoryViewData)
+
+        return reactionHistoryCell
+    }
+}
+
+// MARK: - UITableViewDelegate
+extension ReactionHistoryViewController: UITableViewDelegate {
+    
+    func scrollViewDidScroll(_ scrollView: UIScrollView) {
+        
+        guard self.isViewAppearedOnce else {
+            return
+        }
+        
+        // Check if a scroll beyond scroll view content occurs
+        let distanceFromBottom = scrollView.contentSize.height - scrollView.contentOffset.y
+        if distanceFromBottom < scrollView.frame.size.height {
+            self.viewModel.process(viewAction: .loadMore)
+        }
+    }
+}
+
+// MARK: - ReactionHistoryViewModelViewDelegate
+extension ReactionHistoryViewController: ReactionHistoryViewModelViewDelegate {
+
+    func reactionHistoryViewModel(_ viewModel: ReactionHistoryViewModelType, didUpdateViewState viewSate: ReactionHistoryViewState) {
+        self.render(viewState: viewSate)
+    }
+}