deltachat-ios/deltachat-ios/ChatViewController.swift

//
//  ChatViewController.swift
//  deltachat-ios
//
//  Created by Bastian van de Wetering on 08.11.17.
//  Copyright © 2017 Jonas Reinsch. All rights reserved.
//

import ALCameraViewController
import MapKit
import MessageInputBar
import MessageKit
import QuickLook
import UIKit

class ChatViewController: MessagesViewController {
  let outgoingAvatarOverlap: CGFloat = 17.5
  let loadCount = 30

  let chatId: Int
  let refreshControl = UIRefreshControl()
  var messageList: [MRMessage] = []

  var msgChangedObserver: Any?
  var incomingMsgObserver: Any?

  var disableWriting = false

  var previewView: UIView?
  var previewController: PreviewController?

  init(chatId: Int, title: String? = nil) {
    self.chatId = chatId
    super.init(nibName: nil, bundle: nil)
    if let title = title {
      updateTitleView(title: title, subtitle: nil)
    }
  }

  @objc
  func loadMoreMessages() {
    DispatchQueue.global(qos: .userInitiated).asyncAfter(deadline: .now() + 1) {
      DispatchQueue.main.async {
        self.messageList = self.getMessageIds(self.loadCount, from: self.messageList.count) + self.messageList
        self.messagesCollectionView.reloadDataAndKeepOffset()
        self.refreshControl.endRefreshing()
      }
    }
  }

  @objc
  func refreshMessages() {
    DispatchQueue.global(qos: .userInitiated).asyncAfter(deadline: .now() + 1) {
      DispatchQueue.main.async {
        self.messageList = self.getMessageIds(self.messageList.count)
        self.messagesCollectionView.reloadDataAndKeepOffset()
        self.refreshControl.endRefreshing()
        if self.isLastSectionVisible() {
          self.messagesCollectionView.scrollToBottom(animated: true)
        }
      }
    }
  }

  func loadFirstMessages() {
    DispatchQueue.global(qos: .userInitiated).async {
      DispatchQueue.main.async {
        self.messageList = self.getMessageIds(self.loadCount)
        self.messagesCollectionView.reloadData()
        self.refreshControl.endRefreshing()
        self.messagesCollectionView.scrollToBottom(animated: false)
      }
    }
  }

  var textDraft: String? {
    // FIXME: need to free pointer
    if let draft = dc_get_draft(mailboxPointer, UInt32(chatId)) {
      if let text = dc_msg_get_text(draft) {
        let s = String(validatingUTF8: text)!
        return s
      }
      return nil
    }
    return nil
  }

  func getMessageIds(_ count: Int, from: Int? = nil) -> [MRMessage] {
    let cMessageIds = dc_get_chat_msgs(mailboxPointer, UInt32(chatId), 0, 0)

    let ids: [Int]
    if let from = from {
      ids = Utils.copyAndFreeArrayWithOffset(inputArray: cMessageIds, len: count, skipEnd: from)
    } else {
      ids = Utils.copyAndFreeArrayWithLen(inputArray: cMessageIds, len: count)
    }

    let markIds: [UInt32] = ids.map { return UInt32($0) }
    dc_markseen_msgs(mailboxPointer, UnsafePointer(markIds), Int32(ids.count))

    return ids.map {
      MRMessage(id: $0)
    }
  }

  required init?(coder _: NSCoder) {
    fatalError("init(coder:) has not been implemented")
  }

  override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)
    configureMessageMenu()

    if #available(iOS 11.0, *) {
      if disableWriting {
        navigationController?.navigationBar.prefersLargeTitles = true
      }
    }

    let nc = NotificationCenter.default
    msgChangedObserver = nc.addObserver(
      forName: dcNotificationChanged,
      object: nil,
      queue: OperationQueue.main
    ) { notification in
      if let ui = notification.userInfo {
        if self.disableWriting {
          // always refresh, as we can't check currently
          self.refreshMessages()
        } else if let id = ui["message_id"] as? Int {
          if id > 0 {
            self.updateMessage(id)
          }
        }
      }
    }

    incomingMsgObserver = nc.addObserver(
      forName: dcNotificationIncoming,
      object: nil, queue: OperationQueue.main
    ) { notification in
      if let ui = notification.userInfo {
        if self.chatId == ui["chat_id"] as! Int {
          let id = ui["message_id"] as! Int
          if id > 0 {
            self.insertMessage(MRMessage(id: id))
          }
        }
      }
    }
  }

  func setTextDraft() {
    if let text = self.messageInputBar.inputTextView.text {
      let draft = dc_msg_new(mailboxPointer, DC_MSG_TEXT)
      dc_msg_set_text(draft, text.cString(using: .utf8))
      dc_set_draft(mailboxPointer, UInt32(chatId), draft)

      // cleanup
      dc_msg_unref(draft)
    }
  }

  override func viewWillDisappear(_ animated: Bool) {
    super.viewWillDisappear(animated)

    let cnt = Int(dc_get_fresh_msg_cnt(mailboxPointer, UInt32(chatId)))
    logger.info("updating count for chat \(cnt)")
    UIApplication.shared.applicationIconBadgeNumber = cnt

    if #available(iOS 11.0, *) {
      if disableWriting {
        navigationController?.navigationBar.prefersLargeTitles = false
      }
    }
  }

  override func viewDidDisappear(_ animated: Bool) {
    super.viewDidDisappear(animated)

    setTextDraft()
    let nc = NotificationCenter.default
    if let msgChangedObserver = self.msgChangedObserver {
      nc.removeObserver(msgChangedObserver)
    }
    if let incomingMsgObserver = self.incomingMsgObserver {
      nc.removeObserver(incomingMsgObserver)
    }
  }

  override var inputAccessoryView: UIView? {
    if disableWriting {
      return nil
    }

    return messageInputBar
  }

  override func viewDidLoad() {
    messagesCollectionView.register(CustomCell.self)
    super.viewDidLoad()

    if !MRConfig.configured {
      // TODO: display message about nothing being configured
      return
    }

    let chat = MRChat(id: chatId)
    updateTitleView(title: chat.name, subtitle: chat.subtitle)

    configureMessageCollectionView()

    if !disableWriting {
      configureMessageInputBar()
      messageInputBar.inputTextView.text = textDraft
      messageInputBar.inputTextView.becomeFirstResponder()
    }

    loadFirstMessages()
  }

  func configureMessageMenu() {
    var menuItems: [UIMenuItem]

    if disableWriting {
      menuItems = [
        UIMenuItem(title: "Start Chat", action: #selector(MessageCollectionViewCell.messageStartChat(_:))),
        UIMenuItem(title: "Dismiss", action: #selector(MessageCollectionViewCell.messageDismiss(_:))),
        UIMenuItem(title: "Block", action: #selector(MessageCollectionViewCell.messageBlock(_:))),
      ]
    } else {
      // Configures the UIMenu which is shown when selecting a message
      menuItems = [
        UIMenuItem(title: "Info", action: #selector(MessageCollectionViewCell.messageInfo(_:))),
      ]
    }

    UIMenuController.shared.menuItems = menuItems
  }

  func configureMessageCollectionView() {
    messagesCollectionView.messagesDataSource = self
    messagesCollectionView.messageCellDelegate = self

    scrollsToBottomOnKeyboardBeginsEditing = true // default false
    maintainPositionOnKeyboardFrameChanged = true // default false

    messagesCollectionView.addSubview(refreshControl)
    refreshControl.addTarget(self, action: #selector(loadMoreMessages), for: .valueChanged)

    let layout = messagesCollectionView.collectionViewLayout as? MessagesCollectionViewFlowLayout
    layout?.sectionInset = UIEdgeInsets(top: 1, left: 8, bottom: 1, right: 8)

    // Hide the outgoing avatar and adjust the label alignment to line up with the messages
    layout?.setMessageOutgoingAvatarSize(.zero)
    layout?.setMessageOutgoingMessageTopLabelAlignment(LabelAlignment(textAlignment: .right, textInsets: UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 8)))
    layout?.setMessageOutgoingMessageBottomLabelAlignment(LabelAlignment(textAlignment: .right, textInsets: UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 8)))

    // Set outgoing avatar to overlap with the message bubble
    layout?.setMessageIncomingMessageTopLabelAlignment(LabelAlignment(textAlignment: .left, textInsets: UIEdgeInsets(top: 0, left: 18, bottom: outgoingAvatarOverlap, right: 0)))
    layout?.setMessageIncomingAvatarSize(CGSize(width: 30, height: 30))
    layout?.setMessageIncomingMessagePadding(UIEdgeInsets(top: -outgoingAvatarOverlap, left: -18, bottom: outgoingAvatarOverlap / 2, right: 18))
    layout?.setMessageIncomingMessageBottomLabelAlignment(LabelAlignment(textAlignment: .left, textInsets: UIEdgeInsets(top: -7, left: 38, bottom: 0, right: 0)))

    layout?.setMessageIncomingAccessoryViewSize(CGSize(width: 30, height: 30))
    layout?.setMessageIncomingAccessoryViewPadding(HorizontalEdgeInsets(left: 8, right: 0))
    layout?.setMessageOutgoingAccessoryViewSize(CGSize(width: 30, height: 30))
    layout?.setMessageOutgoingAccessoryViewPadding(HorizontalEdgeInsets(left: 0, right: 8))

    messagesCollectionView.messagesLayoutDelegate = self
    messagesCollectionView.messagesDisplayDelegate = self
  }

  func configureMessageInputBar() {
    messageInputBar.delegate = self
    messageInputBar.inputTextView.tintColor = Constants.primaryColor
    messageInputBar.sendButton.tintColor = Constants.primaryColor

    messageInputBar.isTranslucent = true
    messageInputBar.separatorLine.isHidden = true
    messageInputBar.inputTextView.tintColor = Constants.primaryColor

    messageInputBar.delegate = self
    scrollsToBottomOnKeyboardBeginsEditing = true

    messageInputBar.inputTextView.backgroundColor = UIColor(red: 245 / 255, green: 245 / 255, blue: 245 / 255, alpha: 1)
    messageInputBar.inputTextView.placeholderTextColor = UIColor(red: 0.6, green: 0.6, blue: 0.6, alpha: 1)
    messageInputBar.inputTextView.textContainerInset = UIEdgeInsets(top: 8, left: 16, bottom: 8, right: 38)
    messageInputBar.inputTextView.placeholderLabelInsets = UIEdgeInsets(top: 8, left: 20, bottom: 8, right: 38)
    messageInputBar.inputTextView.layer.borderColor = UIColor(red: 200 / 255, green: 200 / 255, blue: 200 / 255, alpha: 1).cgColor
    messageInputBar.inputTextView.layer.borderWidth = 1.0
    messageInputBar.inputTextView.layer.cornerRadius = 16.0
    messageInputBar.inputTextView.layer.masksToBounds = true
    messageInputBar.inputTextView.scrollIndicatorInsets = UIEdgeInsets(top: 8, left: 0, bottom: 8, right: 0)
    configureInputBarItems()
  }

  private func configureInputBarItems() {
    messageInputBar.setLeftStackViewWidthConstant(to: 44, animated: false)
    messageInputBar.setRightStackViewWidthConstant(to: 36, animated: false)

    let sendButtonImage = UIImage(named: "paper_plane")?.withRenderingMode(.alwaysTemplate)
    messageInputBar.sendButton.image = sendButtonImage
    messageInputBar.sendButton.tintColor = UIColor(white: 1, alpha: 1)
    messageInputBar.sendButton.backgroundColor = UIColor(white: 0.9, alpha: 1)
    messageInputBar.sendButton.contentEdgeInsets = UIEdgeInsets(top: 6, left: 0, bottom: 6, right: 0)
    messageInputBar.sendButton.setSize(CGSize(width: 34, height: 34), animated: false)

    messageInputBar.sendButton.title = nil
    messageInputBar.sendButton.layer.cornerRadius = 18

    messageInputBar.textViewPadding.right = -40

    let leftItems = [
      InputBarButtonItem()
        .configure {
          $0.spacing = .fixed(0)
          $0.image = UIImage(named: "camera")?.withRenderingMode(.alwaysTemplate)
          $0.setSize(CGSize(width: 36, height: 36), animated: false)
          $0.tintColor = UIColor(white: 0.8, alpha: 1)
        }.onSelected {
          $0.tintColor = Constants.primaryColor
        }.onDeselected {
          $0.tintColor = UIColor(white: 0.8, alpha: 1)
        }.onTouchUpInside { _ in
          self.didPressPhotoButton()
        },
    ]
    messageInputBar.setStackViewItems(leftItems, forStack: .left, animated: false)

    // This just adds some more flare
    messageInputBar.sendButton
      .onEnabled { item in
        UIView.animate(withDuration: 0.3, animations: {
          item.backgroundColor = Constants.primaryColor
        })
      }.onDisabled { item in
        UIView.animate(withDuration: 0.3, animations: {
          item.backgroundColor = UIColor(white: 0.9, alpha: 1)
        })
      }
  }

  // MARK: - UICollectionViewDataSource

  public override func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
    guard let messagesCollectionView = collectionView as? MessagesCollectionView else {
      fatalError("notMessagesCollectionView")
    }

    guard let messagesDataSource = messagesCollectionView.messagesDataSource else {
      fatalError("nilMessagesDataSource")
    }

    let message = messagesDataSource.messageForItem(at: indexPath, in: messagesCollectionView)
    switch message.kind {
    case .text, .attributedText, .emoji:
      let cell = messagesCollectionView.dequeueReusableCell(TextMessageCell.self, for: indexPath)
      cell.configure(with: message, at: indexPath, and: messagesCollectionView)
      return cell
    case .photo, .video:
      let cell = messagesCollectionView.dequeueReusableCell(MediaMessageCell.self, for: indexPath)
      cell.configure(with: message, at: indexPath, and: messagesCollectionView)
      return cell
    case .location:
      let cell = messagesCollectionView.dequeueReusableCell(LocationMessageCell.self, for: indexPath)
      cell.configure(with: message, at: indexPath, and: messagesCollectionView)
      return cell
    case .custom:
      let cell = messagesCollectionView.dequeueReusableCell(CustomCell.self, for: indexPath)
      cell.configure(with: message, at: indexPath, and: messagesCollectionView)

      return cell
    }
  }

  override func collectionView(_ collectionView: UICollectionView, canPerformAction action: Selector, forItemAt indexPath: IndexPath, withSender sender: Any?) -> Bool {
    if action == NSSelectorFromString("messageInfo:") ||
      action == NSSelectorFromString("messageBlock:") ||
      action == NSSelectorFromString("messageDismiss:") ||
      action == NSSelectorFromString("messageStartChat:") {
      return true
    } else {
      return super.collectionView(collectionView, canPerformAction: action, forItemAt: indexPath, withSender: sender)
    }
  }

  override func collectionView(_ collectionView: UICollectionView, performAction action: Selector, forItemAt indexPath: IndexPath, withSender sender: Any?) {
    switch action {
    case NSSelectorFromString("messageInfo:"):
      let msg = messageList[indexPath.section]
      logger.info("message: View info \(msg.messageId)")

      let msgViewController = MessageInfoViewController(message: msg)
      if let ctrl = navigationController {
        ctrl.pushViewController(msgViewController, animated: true)
      }
    case NSSelectorFromString("messageStartChat:"):
      let msg = messageList[indexPath.section]
      logger.info("message: Start Chat \(msg.messageId)")
      _ = msg.createChat()
      // TODO: figure out how to properly show the chat after creation

      refreshMessages()
    case NSSelectorFromString("messageBlock:"):
      let msg = messageList[indexPath.section]
      logger.info("message: Block \(msg.messageId)")
      msg.fromContact.block()

      refreshMessages()
    case NSSelectorFromString("messageDismiss:"):
      let msg = messageList[indexPath.section]
      logger.info("message: Dismiss \(msg.messageId)")
      msg.fromContact.marknoticed()

      refreshMessages()
    default:
      super.collectionView(collectionView, performAction: action, forItemAt: indexPath, withSender: sender)
    }
  }
}

// MARK: - MessagesDataSource

extension ChatViewController: MessagesDataSource {
  func numberOfSections(in _: MessagesCollectionView) -> Int {
    return messageList.count
  }

  func currentSender() -> Sender {
    let currentSender = Sender(id: "1", displayName: "Alice")
    return currentSender
  }

  func messageForItem(at indexPath: IndexPath, in _: MessagesCollectionView) -> MessageType {
    return messageList[indexPath.section]
  }

  func avatar(for message: MessageType, at indexPath: IndexPath, in _: MessagesCollectionView) -> Avatar {
    let message = messageList[indexPath.section]
    let contact = message.fromContact
    return Avatar(image: contact.profileImage, initials: Utils.getInitials(inputName: contact.name))
  }

  func cellTopLabelAttributedText(for message: MessageType, at indexPath: IndexPath) -> NSAttributedString? {
    if isInfoMessage(at: indexPath) {
      return nil
    }

    if isTimeLabelVisible(at: indexPath) {
      return NSAttributedString(
        string: MessageKitDateFormatter.shared.string(from: message.sentDate),
        attributes: [
          NSAttributedString.Key.font: UIFont.boldSystemFont(ofSize: 10),
          NSAttributedString.Key.foregroundColor: UIColor.darkGray,
        ]
      )
    }

    return nil
  }

  func messageTopLabelAttributedText(for message: MessageType, at indexPath: IndexPath) -> NSAttributedString? {
    if !isPreviousMessageSameSender(at: indexPath) {
      let name = message.sender.displayName
      let m = messageList[indexPath.section]
      return NSAttributedString(string: name, attributes: [
        .font: UIFont.systemFont(ofSize: 14),
        .foregroundColor: m.fromContact.color,
      ])
    }
    return nil
  }

  func isTimeLabelVisible(at indexPath: IndexPath) -> Bool {
    guard indexPath.section + 1 < messageList.count else { return false }

    let messageA = messageList[indexPath.section]
    let messageB = messageList[indexPath.section + 1]

    if messageA.fromContactId == messageB.fromContactId {
      return false
    }

    let calendar = NSCalendar(calendarIdentifier: NSCalendar.Identifier.gregorian)
    let dateA = messageA.sentDate
    let dateB = messageB.sentDate

    let dayA = (calendar?.component(.day, from: dateA))
    let dayB = (calendar?.component(.day, from: dateB))

    return dayA != dayB
  }

  func isPreviousMessageSameSender(at indexPath: IndexPath) -> Bool {
    guard indexPath.section - 1 >= 0 else { return false }
    let messageA = messageList[indexPath.section - 1]
    let messageB = messageList[indexPath.section]

    if messageA.isInfo {
      return false
    }

    return messageA.fromContactId == messageB.fromContactId
  }

  func isInfoMessage(at indexPath: IndexPath) -> Bool {
    return messageList[indexPath.section].isInfo
  }

  func isNextMessageSameSender(at indexPath: IndexPath) -> Bool {
    guard indexPath.section + 1 < messageList.count else { return false }
    let messageA = messageList[indexPath.section]
    let messageB = messageList[indexPath.section + 1]

    if messageA.isInfo {
      return false
    }

    return messageA.fromContactId == messageB.fromContactId
  }

  func messageBottomLabelAttributedText(for message: MessageType, at indexPath: IndexPath) -> NSAttributedString? {
    guard indexPath.section < messageList.count else { return nil }
    let m = messageList[indexPath.section]

    if m.isInfo || isNextMessageSameSender(at: indexPath) {
      return nil
    }

    let timestampAttributes: [NSAttributedString.Key: Any] = [
      .font: UIFont.systemFont(ofSize: 12),
      .foregroundColor: UIColor.lightGray,
    ]

    if isFromCurrentSender(message: message) {
      let text = NSMutableAttributedString()
      text.append(NSAttributedString(string: m.formattedSentDate(), attributes: timestampAttributes))

      text.append(NSAttributedString(
        string: " - " + m.stateDescription(),
        attributes: [
          .font: UIFont.systemFont(ofSize: 12),
          .foregroundColor: UIColor.darkText,
        ]
      ))

      return text
    }

    return NSAttributedString(string: m.formattedSentDate(), attributes: timestampAttributes)
  }

  func updateMessage(_ messageId: Int) {
    if let index = messageList.firstIndex(where: { $0.id == messageId }) {
      dc_markseen_msgs(mailboxPointer, UnsafePointer([UInt32(messageId)]), 1)

      messageList[index] = MRMessage(id: messageId)
      // Reload section to update header/footer labels
      messagesCollectionView.performBatchUpdates({
        messagesCollectionView.reloadSections([index])
        if index > 0 {
          messagesCollectionView.reloadSections([index - 1])
        }
        if index < messageList.count - 1 {
          messagesCollectionView.reloadSections([index + 1])
        }
      }, completion: { [weak self] _ in
        if self?.isLastSectionVisible() == true {
          self?.messagesCollectionView.scrollToBottom(animated: true)
        }
      })
    } else {
      let msg = MRMessage(id: messageId)
      if msg.chatId == chatId {
        insertMessage(msg)
      }
    }
  }

  func insertMessage(_ message: MRMessage) {
    dc_markseen_msgs(mailboxPointer, UnsafePointer([UInt32(message.id)]), 1)
    messageList.append(message)
    // Reload last section to update header/footer labels and insert a new one
    messagesCollectionView.performBatchUpdates({
      messagesCollectionView.insertSections([messageList.count - 1])
      if messageList.count >= 2 {
        messagesCollectionView.reloadSections([messageList.count - 2])
      }
    }, completion: { [weak self] _ in
      if self?.isLastSectionVisible() == true {
        self?.messagesCollectionView.scrollToBottom(animated: true)
      }
    })
  }

  func isLastSectionVisible() -> Bool {
    guard !messageList.isEmpty else { return false }

    let lastIndexPath = IndexPath(item: 0, section: messageList.count - 1)
    return messagesCollectionView.indexPathsForVisibleItems.contains(lastIndexPath)
  }
}

// MARK: - MessagesDisplayDelegate

extension ChatViewController: MessagesDisplayDelegate {
  // MARK: - Text Messages

  func textColor(for _: MessageType, at _: IndexPath, in _: MessagesCollectionView) -> UIColor {
    return .darkText
  }

  // MARK: - All Messages

  func backgroundColor(for message: MessageType, at _: IndexPath, in _: MessagesCollectionView) -> UIColor {
    return isFromCurrentSender(message: message) ? Constants.messagePrimaryColor : Constants.messageSecondaryColor
  }

  func messageStyle(for message: MessageType, at indexPath: IndexPath, in _: MessagesCollectionView) -> MessageStyle {
    if isInfoMessage(at: indexPath) {
      return .custom { view in
        view.style = .none
        view.backgroundColor = UIColor(alpha: 10, red: 0, green: 0, blue: 0)
        let radius: CGFloat = 16
        let path = UIBezierPath(roundedRect: view.bounds, byRoundingCorners: UIRectCorner.allCorners, cornerRadii: CGSize(width: radius, height: radius))
        let mask = CAShapeLayer()
        mask.path = path.cgPath
        view.layer.mask = mask
        view.center.x = self.view.center.x
      }
    }

    var corners: UIRectCorner = []

    if isFromCurrentSender(message: message) {
      corners.formUnion(.topLeft)
      corners.formUnion(.bottomLeft)
      if !isPreviousMessageSameSender(at: indexPath) {
        corners.formUnion(.topRight)
      }
      if !isNextMessageSameSender(at: indexPath) {
        corners.formUnion(.bottomRight)
      }
    } else {
      corners.formUnion(.topRight)
      corners.formUnion(.bottomRight)
      if !isPreviousMessageSameSender(at: indexPath) {
        corners.formUnion(.topLeft)
      }
      if !isNextMessageSameSender(at: indexPath) {
        corners.formUnion(.bottomLeft)
      }
    }

    return .custom { view in
      let radius: CGFloat = 16
      let path = UIBezierPath(roundedRect: view.bounds, byRoundingCorners: corners, cornerRadii: CGSize(width: radius, height: radius))
      let mask = CAShapeLayer()
      mask.path = path.cgPath
      view.layer.mask = mask
    }
  }

  func configureAvatarView(_ avatarView: AvatarView, for message: MessageType, at indexPath: IndexPath, in _: MessagesCollectionView) {
    let message = messageList[indexPath.section]
    let contact = message.fromContact
    let avatar = Avatar(image: contact.profileImage, initials: Utils.getInitials(inputName: contact.name))
    avatarView.set(avatar: avatar)
    avatarView.isHidden = isNextMessageSameSender(at: indexPath) || message.isInfo
    avatarView.backgroundColor = contact.color
  }

  func enabledDetectors(for _: MessageType, at _: IndexPath, in _: MessagesCollectionView) -> [DetectorType] {
    return [.url, .date, .phoneNumber, .address]
  }
}

// MARK: - MessagesLayoutDelegate

extension ChatViewController: MessagesLayoutDelegate {
  func cellTopLabelHeight(for _: MessageType, at indexPath: IndexPath, in _: MessagesCollectionView) -> CGFloat {
    if isTimeLabelVisible(at: indexPath) {
      return 18
    }
    return 0
  }

  func messageTopLabelHeight(for message: MessageType, at indexPath: IndexPath, in _: MessagesCollectionView) -> CGFloat {
    if isInfoMessage(at: indexPath) {
      return 0
    }

    if isFromCurrentSender(message: message) {
      return !isPreviousMessageSameSender(at: indexPath) ? 40 : 0
    } else {
      return !isPreviousMessageSameSender(at: indexPath) ? (40 + outgoingAvatarOverlap) : 0
    }
  }

  func messageBottomLabelHeight(for message: MessageType, at indexPath: IndexPath, in _: MessagesCollectionView) -> CGFloat {
    if isInfoMessage(at: indexPath) {
      return 0
    }

    if !isNextMessageSameSender(at: indexPath) {
      return 16
    }

    if isFromCurrentSender(message: message) {
      return 0
    }

    return 9
  }

  func heightForLocation(message _: MessageType, at _: IndexPath, with _: CGFloat, in _: MessagesCollectionView) -> CGFloat {
    return 40
  }

  func footerViewSize(for _: MessageType, at _: IndexPath, in messagesCollectionView: MessagesCollectionView) -> CGSize {
    return CGSize(width: messagesCollectionView.bounds.width, height: 20)
  }

  @objc func didPressPhotoButton() {
    if UIImagePickerController.isSourceTypeAvailable(.camera) {
      let cameraViewController = CameraViewController { [weak self] image, _ in
        self?.dismiss(animated: true, completion: nil)

        DispatchQueue.global().async {
          if let pickedImage = image {
            let width = Int32(exactly: pickedImage.size.width)!
            let height = Int32(exactly: pickedImage.size.height)!
            let path = Utils.saveImage(image: pickedImage)
            let msg = dc_msg_new(mailboxPointer, DC_MSG_IMAGE)
            dc_msg_set_file(msg, path, "image/jpeg")
            dc_msg_set_dimension(msg, width, height)
            dc_send_msg(mailboxPointer, UInt32(self!.chatId), msg)

            // cleanup
            dc_msg_unref(msg)
          }
        }
      }

      present(cameraViewController, animated: true, completion: nil)
    } else {
      let alert = UIAlertController(title: "Camera is not available", message: nil, preferredStyle: .alert)
      alert.addAction(UIAlertAction(title: "OK", style: .cancel, handler: { _ in
        self.dismiss(animated: true, completion: nil)
      }))
      present(alert, animated: true, completion: nil)
    }
  }
}

// MARK: - MessageCellDelegate

extension ChatViewController: MessageCellDelegate {
  func didTapMessage(in cell: MessageCollectionViewCell) {
    if let indexPath = messagesCollectionView.indexPath(for: cell) {
      let message = messageList[indexPath.section]

      if let url = message.fileURL {
        previewController = PreviewController(urls: [url])
        present(previewController!.qlController, animated: true)
      }
    }
  }

  func didTapAvatar(in _: MessageCollectionViewCell) {
    logger.info("Avatar tapped")
  }

  @objc(didTapCellTopLabelIn:) func didTapCellTopLabel(in _: MessageCollectionViewCell) {
    logger.info("Top label tapped")
  }

  func didTapBottomLabel(in _: MessageCollectionViewCell) {
    print("Bottom label tapped")
  }
}

class PreviewController: QLPreviewControllerDataSource {
  var urls: [URL]
  var qlController: QLPreviewController

  init(urls: [URL]) {
    self.urls = urls
    qlController = QLPreviewController()
    qlController.dataSource = self
  }

  func numberOfPreviewItems(in _: QLPreviewController) -> Int {
    return urls.count
  }

  func previewController(_: QLPreviewController, previewItemAt index: Int) -> QLPreviewItem {
    return urls[index] as QLPreviewItem
  }
}

// MARK: - MessageLabelDelegate

extension ChatViewController: MessageLabelDelegate {
  func didSelectAddress(_ addressComponents: [String: String]) {
    let mapAddress = Utils.formatAddressForQuery(address: addressComponents)
    if let escapedMapAddress = mapAddress.addingPercentEncoding(withAllowedCharacters: .urlQueryAllowed) {
      // Use query, to handle malformed addresses
      if let url = URL(string: "http://maps.apple.com/?q=\(escapedMapAddress)") {
        UIApplication.shared.open(url as URL)
      }
    }
  }

  func didSelectDate(_ date: Date) {
    let interval = date.timeIntervalSinceReferenceDate
    if let url = NSURL(string: "calshow:\(interval)") {
      UIApplication.shared.open(url as URL)
    }
  }

  func didSelectPhoneNumber(_ phoneNumber: String) {
    logger.info("phone open", phoneNumber)
    if let escapedPhoneNumber = phoneNumber.addingPercentEncoding(withAllowedCharacters: .urlQueryAllowed) {
      if let url = NSURL(string: "tel:\(escapedPhoneNumber)") {
        UIApplication.shared.open(url as URL)
      }
    }
  }

  func didSelectURL(_ url: URL) {
    UIApplication.shared.open(url)
  }
}

// MARK: - LocationMessageDisplayDelegate

/*
 extension ChatViewController: LocationMessageDisplayDelegate {
 func annotationViewForLocation(message: MessageType, at indexPath: IndexPath, in messageCollectionView: MessagesCollectionView) -> MKAnnotationView? {
 let annotationView = MKAnnotationView(annotation: nil, reuseIdentifier: nil)
 let pinImage = #imageLiteral(resourceName: "ic_block_36pt").withRenderingMode(.alwaysTemplate)
 annotationView.image = pinImage
 annotationView.centerOffset = CGPoint(x: 0, y: -pinImage.size.height / 2)
 return annotationView
 }

 func animationBlockForLocation(message: MessageType, at indexPath: IndexPath, in messagesCollectionView: MessagesCollectionView) -> ((UIImageView) -> Void)? {
 return { view in
 view.layer.transform = CATransform3DMakeScale(0, 0, 0)
 view.alpha = 0.0
 UIView.animate(withDuration: 0.6, delay: 0, usingSpringWithDamping: 0.9, initialSpringVelocity: 0, options: [], animations: {
 view.layer.transform = CATransform3DIdentity
 view.alpha = 1.0
 }, completion: nil)
 }
 }
 }
 */

// MARK: - MessageInputBarDelegate

extension ChatViewController: MessageInputBarDelegate {
  func messageInputBar(_ inputBar: MessageInputBar, didPressSendButtonWith text: String) {
    DispatchQueue.global().async {
      dc_send_text_msg(mailboxPointer, UInt32(self.chatId), text)
    }
    inputBar.inputTextView.text = String()
  }
}

// MARK: - MessageCollectionViewCell

extension MessageCollectionViewCell {
  @objc func messageInfo(_ sender: Any?) {
    // Get the collectionView
    if let collectionView = self.superview as? UICollectionView {
      // Get indexPath
      if let indexPath = collectionView.indexPath(for: self) {
        // Trigger action
        collectionView.delegate?.collectionView?(collectionView, performAction: #selector(MessageCollectionViewCell.messageInfo(_:)), forItemAt: indexPath, withSender: sender)
      }
    }
  }

  @objc func messageBlock(_ sender: Any?) {
    // Get the collectionView
    if let collectionView = self.superview as? UICollectionView {
      // Get indexPath
      if let indexPath = collectionView.indexPath(for: self) {
        // Trigger action
        collectionView.delegate?.collectionView?(collectionView, performAction: #selector(MessageCollectionViewCell.messageBlock(_:)), forItemAt: indexPath, withSender: sender)
      }
    }
  }

  @objc func messageDismiss(_ sender: Any?) {
    // Get the collectionView
    if let collectionView = self.superview as? UICollectionView {
      // Get indexPath
      if let indexPath = collectionView.indexPath(for: self) {
        // Trigger action
        collectionView.delegate?.collectionView?(collectionView, performAction: #selector(MessageCollectionViewCell.messageDismiss(_:)), forItemAt: indexPath, withSender: sender)
      }
    }
  }

  @objc func messageStartChat(_ sender: Any?) {
    // Get the collectionView
    if let collectionView = self.superview as? UICollectionView {
      // Get indexPath
      if let indexPath = collectionView.indexPath(for: self) {
        // Trigger action
        collectionView.delegate?.collectionView?(collectionView, performAction: #selector(MessageCollectionViewCell.messageStartChat(_:)), forItemAt: indexPath, withSender: sender)
      }
    }
  }
}