Update profile header to always reflect most recently cached data

Tusker/Views/Profile Header/ProfileHeaderTableViewCell.swift

@@ -8,6 +8,7 @@
 
 import UIKit
 import Pachyderm
+import Combine
 
 protocol ProfileHeaderTableViewCellDelegate: TuskerNavigationDelegate {
     func showMoreOptions(cell: ProfileHeaderTableViewCell)
@@ -35,6 +36,8 @@ class ProfileHeaderTableViewCell: UITableViewCell {
     var avatarRequest: ImageCache.Request?
     var headerRequest: ImageCache.Request?
     
+    private var accountUpdater: Cancellable?
+
     override func awakeFromNib() {
         avatarContainerView.layer.masksToBounds = true
         avatarImageView.layer.masksToBounds = true
@@ -62,7 +65,6 @@ class ProfileHeaderTableViewCell: UITableViewCell {
         
         usernameLabel.text = "@\(account.acct)"
         
-        avatarImageView.image = nil
         avatarRequest = ImageCache.avatars.get(account.avatar) { [weak self] (data) in
             guard let self = self, let data = data, self.accountID == accountID else { return }
             self.avatarRequest = nil
@@ -70,7 +72,6 @@ class ProfileHeaderTableViewCell: UITableViewCell {
                 self.avatarImageView.image = UIImage(data: data)
             }
         }
-        headerImageView.image = nil
         headerRequest = ImageCache.headers.get(account.header) { [weak self] (data) in
             guard let self = self, let data = data, self.accountID == accountID else { return }
             self.headerRequest = nil
@@ -99,6 +100,7 @@ class ProfileHeaderTableViewCell: UITableViewCell {
         if let fields = account.fields, !fields.isEmpty {
             fieldsStackView.isHidden = false
             
+            fieldsStackView.arrangedSubviews.forEach { $0.removeFromSuperview() }
             for field in fields {
                 let nameLabel = UILabel()
                 nameLabel.text = field.name
@@ -120,6 +122,13 @@ class ProfileHeaderTableViewCell: UITableViewCell {
         } else {
             fieldsStackView.isHidden = true
         }
+        
+        if accountUpdater == nil {
+            accountUpdater = mastodonController.cache.accountSubject
+                .filter { [unowned self] in $0.id == self.accountID }
+                .receive(on: DispatchQueue.main)
+                .sink { [unowned self] in self.updateUI(for: $0.id) }
+        }
     }
 
     @objc func updateUIForPreferences() {