mattermost-mobile/ios/NotificationService/NotificationService.swift

import Gekidou
import UserNotifications
import Intents
import os.log

class NotificationService: UNNotificationServiceExtension {
  var contentHandler: ((UNNotificationContent) -> Void)?
  var bestAttemptContent: UNMutableNotificationContent?
  
  override init() {
    super.init()
    initSentryAppExt()
  }
  
  override func didReceive(_ request: UNNotificationRequest, withContentHandler contentHandler: @escaping (UNNotificationContent) -> Void) {
    self.contentHandler = contentHandler

    bestAttemptContent = (request.content.mutableCopy() as? UNMutableNotificationContent)
    if let bestAttemptContent = bestAttemptContent {
      PushNotification.default.postNotificationReceipt(bestAttemptContent, completionHandler: {[weak self] notification in
        if let notification = notification {
          self?.bestAttemptContent = notification
          if (Gekidou.Preferences.default.object(forKey: "ApplicationIsRunning") as? String != "true") {
            PushNotification.default.fetchAndStoreDataForPushNotification(bestAttemptContent, withContentHandler: {notification in
              os_log(OSLogType.default, "Mattermost Notifications: processed data for db. Will call sendMessageIntent")
              self?.sendMessageIntent()
            })
          } else {
            bestAttemptContent.badge = Gekidou.Database.default.getTotalMentions() as NSNumber
            os_log(OSLogType.default, "Mattermost Notifications: app in the foreground, no data processed. Will call sendMessageIntent")
            self?.sendMessageIntent()
          }
          return
        }
        
        os_log(OSLogType.default, "Mattermost Notifications: notification receipt seems to be empty, will call sendMessageIntent")
        self?.sendMessageIntent()
      })
    } else {
      os_log(OSLogType.default, "Mattermost Notifications: bestAttemptContent seems to be empty, will call sendMessageIntent")
      sendMessageIntent()
    }
  }

  override func serviceExtensionTimeWillExpire() {
    // Called just before the extension will be terminated by the system.
    // Use this as an opportunity to deliver your "best attempt" at modified content, otherwise the original push payload will be used.
    os_log(OSLogType.default, "Mattermost Notifications: service extension time expired")
    os_log(OSLogType.default, "Mattermost Notifications: calling sendMessageIntent before expiration")
    sendMessageIntent()
  }
  
  private func sendMessageIntent() {
    guard let notification = bestAttemptContent else { return }
    if #available(iOSApplicationExtension 15.0, *) {
      let overrideUsername = notification.userInfo["override_username"] as? String
      let senderId = notification.userInfo["sender_id"] as? String
      let sender = overrideUsername ?? senderId

      guard let serverUrl = notification.userInfo["server_url"] as? String,
              let sender = sender
      else {
        os_log(OSLogType.default, "Mattermost Notifications: No intent created. will call contentHandler to present notification")
        self.contentHandler?(notification)
        return
      }

      let overrideIconUrl = notification.userInfo["override_icon_url"] as? String
      os_log(OSLogType.default, "Mattermost Notifications: Fetching profile Image in server %{public}@ for sender %{public}@", serverUrl, sender)
        
      PushNotification.default.fetchProfileImageSync(serverUrl, senderId: sender, overrideIconUrl: overrideIconUrl) {[weak self] data in
        self?.sendMessageIntentCompletion(data)
      }
    }
  }
  
  private func sendMessageIntentCompletion(_ avatarData: Data?) {
    guard let notification = bestAttemptContent else { return }
    if #available(iOSApplicationExtension 15.0, *),
       let imgData = avatarData,
       let channelId = notification.userInfo["channel_id"] as? String {
      os_log(OSLogType.default, "Mattermost Notifications: creating intent")

      let isCRTEnabled = notification.userInfo["is_crt_enabled"] as? Bool ?? false
      let rootId = notification.userInfo["root_id"] as? String ?? ""
      let channelName = notification.userInfo["channel_name"] as? String ?? ""
      let message = (notification.userInfo["message"] as? String ?? "")
      let overrideUsername = notification.userInfo["override_username"] as? String
      let senderId = notification.userInfo["sender_id"] as? String
      let senderIdentifier = overrideUsername ?? senderId
      let avatar = INImage(imageData: imgData) as INImage?

      var conversationId = channelId
      if isCRTEnabled && !rootId.isEmpty {
        conversationId = rootId
      }

      let handle = INPersonHandle(value: senderIdentifier, type: .unknown)
      let sender = INPerson(personHandle: handle,
                            nameComponents: nil,
                            displayName: channelName,
                            image: avatar,
                            contactIdentifier: nil,
                            customIdentifier: nil)

      let intent = INSendMessageIntent(recipients: nil,
                                       outgoingMessageType: .outgoingMessageText,
                                       content: message,
                                       speakableGroupName: nil,
                                       conversationIdentifier: conversationId,
                                       serviceName: nil,
                                       sender: sender,
                                       attachments: nil)

      let interaction = INInteraction(intent: intent, response: nil)
      interaction.direction = .incoming
      interaction.donate { error in
        if error != nil {
          self.contentHandler?(notification)
          os_log(OSLogType.default, "Mattermost Notifications: sendMessageIntent intent error %{public}@", error! as CVarArg)
        }
        
        do {
          let updatedContent = try notification.updating(from: intent)
          os_log(OSLogType.default, "Mattermost Notifications: present updated notification")
          self.contentHandler?(updatedContent)
        } catch {
          os_log(OSLogType.default, "Mattermost Notifications: something failed updating the notification %{public}@", error as CVarArg)
          self.contentHandler?(notification)
        }
      }
    } else {
      self.contentHandler?(notification)
    }
  }
}