// TODO
// • Tapping replies
// • Mentions
// • Remaining send logic
// • Subtitle
// • Resending failed messages
// • Link previews
// • Slight paging glitch
// • Scrolling bug
final class ConversationVC : BaseVC, ConversationViewModelDelegate, UITableViewDataSource, UITableViewDelegate {
let thread: TSThread
private let focusedMessageID: String?
var audioPlayer: OWSAudioPlayer?
private var didConstrainScrollButton = false
// Context menu
var contextMenuWindow: ContextMenuWindow?
var contextMenuVC: ContextMenuVC?
// Scrolling & paging
private var isUserScrolling = false
private var hasPerformedInitialScroll = false
private var isLoadingMore = false
private var scrollDistanceToBottomBeforeUpdate: CGFloat?
private var dbConnection: YapDatabaseConnection { OWSPrimaryStorage.shared().uiDatabaseConnection }
var viewItems: [ConversationViewItem] { viewModel.viewState.viewItems }
func conversationStyle() -> ConversationStyle { return ConversationStyle(thread: thread) }
override var inputAccessoryView: UIView? { snInputView }
override var canBecomeFirstResponder: Bool { true }
private var tableViewUnobscuredHeight: CGFloat {
let bottomInset = messagesTableView.adjustedContentInset.bottom + ConversationVC.bottomInset
return messagesTableView.bounds.height - bottomInset
}
private var lastPageTop: CGFloat {
return messagesTableView.contentSize.height - tableViewUnobscuredHeight
}
lazy var viewModel = ConversationViewModel(thread: thread, focusMessageIdOnOpen: focusedMessageID, delegate: self)
private lazy var mediaCache: NSCache<NSString, AnyObject> = {
let result = NSCache<NSString, AnyObject>()
result.countLimit = 40
return result
}()
// MARK: UI Components
lazy var messagesTableView: MessagesTableView = {
let result = MessagesTableView()
result.dataSource = self
result.delegate = self
return result
}()
lazy var snInputView = InputView(delegate: self)
private lazy var scrollButton = ScrollToBottomButton(delegate: self)
lazy var blockedBanner: InfoBanner = {
let name: String
if let thread = thread as? TSContactThread {
let publicKey = thread.contactIdentifier()
name = OWSProfileManager.shared().profileNameForRecipient(withID: publicKey, avoidingWriteTransaction: true) ?? publicKey
} else {
name = "Thread"
}
let message = "\(name) is blocked. Unblock them?"
let result = InfoBanner(message: message, backgroundColor: Colors.destructive)
let tapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(unblock))
result.addGestureRecognizer(tapGestureRecognizer)
return result
}()
// MARK: Settings
private static let bottomInset = Values.mediumSpacing
private static let loadMoreThreshold: CGFloat = 120
/// The button will be fully visible once the user has scrolled this amount from the bottom of the table view.
private static let scrollButtonFullVisibilityThreshold: CGFloat = 80
/// The button will be invisible until the user has scrolled at least this amount from the bottom of the table view.
private static let scrollButtonNoVisibilityThreshold: CGFloat = 20
// MARK: Lifecycle
init(thread: TSThread, focusedMessageID: String? = nil) {
self.thread = thread
self.focusedMessageID = focusedMessageID
super.init(nibName: nil, bundle: nil)
}
required init?(coder: NSCoder) {
preconditionFailure("Use init(thread:) instead.")
}
override func viewDidLoad() {
super.viewDidLoad()
// Gradient
setUpGradientBackground()
// Nav bar
setUpNavBarStyle()
setNavBarTitle(getTitle())
updateNavBarButtons()
// Constraints
view.addSubview(messagesTableView)
messagesTableView.pin(to: view)
view.addSubview(scrollButton)
scrollButton.pin(.right, to: .right, of: view, withInset: -Values.mediumSpacing)
// Blocked banner
addOrRemoveBlockedBanner()
// Notifications
let notificationCenter = NotificationCenter.default
notificationCenter.addObserver(self, selector: #selector(handleKeyboardWillChangeFrameNotification(_:)), name: UIResponder.keyboardWillChangeFrameNotification, object: nil)
notificationCenter.addObserver(self, selector: #selector(handleKeyboardWillHideNotification(_:)), name: UIResponder.keyboardWillHideNotification, object: nil)
notificationCenter.addObserver(self, selector: #selector(handleAudioDidFinishPlayingNotification(_:)), name: .SNAudioDidFinishPlaying, object: nil)
notificationCenter.addObserver(self, selector: #selector(addOrRemoveBlockedBanner), name: NSNotification.Name(rawValue: kNSNotificationName_BlockListDidChange), object: nil)
}
override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
if !hasPerformedInitialScroll {
scrollToBottom(isAnimated: false)
hasPerformedInitialScroll = true
}
}
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
markAllAsRead()
}
override func viewDidDisappear(_ animated: Bool) {
super.viewDidDisappear(animated)
mediaCache.removeAllObjects()
}
deinit {
NotificationCenter.default.removeObserver(self)
}
// MARK: Table View Data Source
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return viewItems.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let viewItem = viewItems[indexPath.row]
let cell = tableView.dequeueReusableCell(withIdentifier: MessageCell.getCellType(for: viewItem).identifier) as! MessageCell
cell.delegate = self
cell.viewItem = viewItem
return cell
}
// MARK: Updating
private func updateNavBarButtons() {
let rightBarButtonItem: UIBarButtonItem
if thread is TSContactThread {
let size = Values.verySmallProfilePictureSize
let profilePictureView = ProfilePictureView()
profilePictureView.accessibilityLabel = "Settings button"
profilePictureView.size = size
profilePictureView.update(for: thread)
profilePictureView.set(.width, to: size)
profilePictureView.set(.height, to: size)
let tapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(openSettings))
profilePictureView.addGestureRecognizer(tapGestureRecognizer)
rightBarButtonItem = UIBarButtonItem(customView: profilePictureView)
} else {
rightBarButtonItem = UIBarButtonItem(image: UIImage(named: "Gear"), style: .plain, target: self, action: #selector(openSettings))
}
rightBarButtonItem.accessibilityLabel = "Settings button"
rightBarButtonItem.isAccessibilityElement = true
navigationItem.rightBarButtonItem = rightBarButtonItem
}
@objc private func handleKeyboardWillChangeFrameNotification(_ notification: Notification) {
guard let newHeight = (notification.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue.size.height else { return }
if !didConstrainScrollButton {
// Bit of a hack to do this here, but it works out.
scrollButton.pin(.bottom, to: .bottom, of: view, withInset: -(newHeight + Values.mediumSpacing))
didConstrainScrollButton = true
}
UIView.animate(withDuration: 0.25) {
self.messagesTableView.keyboardHeight = newHeight
self.scrollButton.alpha = 0
}
}
@objc private func handleKeyboardWillHideNotification(_ notification: Notification) {
UIView.animate(withDuration: 0.25) {
self.messagesTableView.keyboardHeight = 0
self.scrollButton.alpha = self.getScrollButtonOpacity()
}
}
func conversationViewModelWillUpdate() {
}
func conversationViewModelDidUpdate(_ conversationUpdate: ConversationUpdate) {
guard self.isViewLoaded else { return }
// TODO: Reload the thread if it's a group thread?
let updateType = conversationUpdate.conversationUpdateType
guard updateType != .minor else { return } // No view items were affected
if updateType == .reload {
return messagesTableView.reloadData()
}
var shouldScrollToBottom = false
let shouldAnimate = conversationUpdate.shouldAnimateUpdates
let batchUpdates: () -> Void = {
for update in conversationUpdate.updateItems! {
switch update.updateItemType {
case .delete:
self.messagesTableView.deleteRows(at: [ IndexPath(row: Int(update.oldIndex), section: 0) ], with: .fade)
case .insert:
// Perform inserts before updates
self.messagesTableView.insertRows(at: [ IndexPath(row: Int(update.newIndex), section: 0) ], with: .fade)
let viewItem = update.viewItem
if viewItem?.interaction is TSOutgoingMessage {
shouldScrollToBottom = true
}
case .update:
self.messagesTableView.reloadRows(at: [ IndexPath(row: Int(update.oldIndex), section: 0) ], with: .fade)
default: preconditionFailure()
}
}
}
let batchUpdatesCompletion: (Bool) -> Void = { isFinished in
// TODO: Update last visible sort ID?
if shouldScrollToBottom {
self.scrollToBottom(isAnimated: true)
}
// TODO: Update last known distance from bottom
}
if shouldAnimate {
messagesTableView.performBatchUpdates(batchUpdates, completion: batchUpdatesCompletion)
} else {
// HACK: We use `UIView.animateWithDuration:0` rather than `UIView.performWithAnimation` to work around a
// UIKit Crash like:
//
// *** Assertion failure in -[ConversationViewLayout prepareForCollectionViewUpdates:],
// /BuildRoot/Library/Caches/com.apple.xbs/Sources/UIKit_Sim/UIKit-3600.7.47/UICollectionViewLayout.m:760
// *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'While
// preparing update a visible view at <NSIndexPath: 0xc000000011c00016> {length = 2, path = 0 - 142}
// wasn't found in the current data model and was not in an update animation. This is an internal
// error.'
//
// I'm unclear if this is a bug in UIKit, or if we're doing something crazy in
// ConversationViewLayout#prepareLayout. To reproduce, rapidily insert and delete items into the
// conversation.
UIView.animate(withDuration: 0) {
self.messagesTableView.performBatchUpdates(batchUpdates, completion: batchUpdatesCompletion)
if shouldScrollToBottom {
self.scrollToBottom(isAnimated: false)
}
}
}
// TODO: Set last reload date?
}
func conversationViewModelWillLoadMoreItems() {
view.layoutIfNeeded()
scrollDistanceToBottomBeforeUpdate = messagesTableView.contentSize.height - messagesTableView.contentOffset.y
}
func conversationViewModelDidLoadMoreItems() {
guard let scrollDistanceToBottomBeforeUpdate = scrollDistanceToBottomBeforeUpdate else { return }
view.layoutIfNeeded()
messagesTableView.contentOffset.y = messagesTableView.contentSize.height - scrollDistanceToBottomBeforeUpdate
isLoadingMore = false
}
func conversationViewModelDidLoadPrevPage() {
}
func conversationViewModelRangeDidChange() {
}
func conversationViewModelDidReset() {
}
@objc private func addOrRemoveBlockedBanner() {
func detach() {
blockedBanner.removeFromSuperview()
}
guard let thread = thread as? TSContactThread else { return detach() }
if OWSBlockingManager.shared().isRecipientIdBlocked(thread.contactIdentifier()) {
view.addSubview(blockedBanner)
blockedBanner.pin([ UIView.HorizontalEdge.left, UIView.VerticalEdge.top, UIView.HorizontalEdge.right ], to: view)
} else {
detach()
}
}
// MARK: General
func markAllAsRead() {
guard let lastSortID = viewItems.last?.interaction.sortId else { return }
OWSReadReceiptManager.shared().markAsReadLocally(beforeSortId: lastSortID, thread: thread)
}
func tableView(_ tableView: UITableView, estimatedHeightForRowAt indexPath: IndexPath) -> CGFloat {
return UITableView.automaticDimension
}
func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
return UITableView.automaticDimension
}
func getMediaCache() -> NSCache<NSString, AnyObject> {
return mediaCache
}
@objc private func handleAudioDidFinishPlayingNotification(_ notification: Notification) {
guard let audioPlayer = audioPlayer, let viewItem = audioPlayer.owner as? ConversationViewItem,
let index = viewItems.firstIndex(where: { $0 === viewItem }), index < (viewItems.endIndex - 1) else { return }
let nextViewItem = viewItems[index + 1]
guard nextViewItem.messageCellType == .audio else { return }
playOrPauseAudio(for: nextViewItem)
}
func scrollToBottom(isAnimated: Bool) {
guard !isUserScrolling else { return }
// Ensure the view is fully up to date before we try to scroll to the bottom, since
// we use the table view's bounds to determine where the bottom is.
view.layoutIfNeeded()
let firstContentPageTop: CGFloat = 0
let contentOffsetY = max(firstContentPageTop, lastPageTop)
messagesTableView.setContentOffset(CGPoint(x: 0, y: contentOffsetY), animated: isAnimated)
// TODO: Did scroll to bottom
}
func scrollViewWillBeginDragging(_ scrollView: UIScrollView) {
isUserScrolling = true
}
func scrollViewDidEndDragging(_ scrollView: UIScrollView, willDecelerate decelerate: Bool) {
isUserScrolling = false
}
func scrollViewDidScroll(_ scrollView: UIScrollView) {
scrollButton.alpha = getScrollButtonOpacity()
autoLoadMoreIfNeeded()
}
private func autoLoadMoreIfNeeded() {
let isMainAppAndActive = CurrentAppContext().isMainAppAndActive
guard isMainAppAndActive && viewModel.canLoadMoreItems() && !isLoadingMore
&& messagesTableView.contentOffset.y < ConversationVC.loadMoreThreshold else { return }
isLoadingMore = true
viewModel.loadAnotherPageOfMessages()
}
// MARK: Convenience
private func getTitle() -> String {
if let thread = thread as? TSGroupThread {
return thread.groupModel.groupName!
} else if thread.isNoteToSelf() {
return "Note to Self"
} else {
let sessionID = thread.contactIdentifier()!
var result = sessionID
Storage.read { transaction in
result = Storage.shared.getContact(with: sessionID)?.displayName ?? "Anonymous"
}
return result
}
}
private func getScrollButtonOpacity() -> CGFloat {
let contentOffsetY = messagesTableView.contentOffset.y
let x = (lastPageTop - ConversationVC.bottomInset - contentOffsetY).clamp(0, .greatestFiniteMagnitude)
let a = 1 / (ConversationVC.scrollButtonFullVisibilityThreshold - ConversationVC.scrollButtonNoVisibilityThreshold)
return a * x
}
}