From 3822d536c86da85770545c2aec563a541fae1285 Mon Sep 17 00:00:00 2001
From: Shadowfacts <me@shadowfacts.net>
Date: Thu, 17 Sep 2020 19:38:49 -0400
Subject: [PATCH] Reduce redundant status database lookups when updating cell
 UI

---
 .../Status/BaseStatusTableViewCell.swift      | 19 +++++++++-----
 .../ConversationMainStatusTableViewCell.swift | 11 ++++----
 .../Status/TimelineStatusTableViewCell.swift  | 26 ++++++++++---------
 3 files changed, 32 insertions(+), 24 deletions(-)

diff --git a/Tusker/Views/Status/BaseStatusTableViewCell.swift b/Tusker/Views/Status/BaseStatusTableViewCell.swift
index 01bbfbea..b93e5b69 100644
--- a/Tusker/Views/Status/BaseStatusTableViewCell.swift
+++ b/Tusker/Views/Status/BaseStatusTableViewCell.swift
@@ -122,19 +122,25 @@ class BaseStatusTableViewCell: UITableViewCell {
         }
     }
     
-    func updateUI(statusID: String, state: StatusState) {
+    final func updateUI(statusID: String, state: StatusState) {
         createObserversIfNecessary()
         
         guard let status = mastodonController.persistentContainer.status(for: statusID) else {
             fatalError("Missing cached status")
         }
+        
         self.statusID = statusID
+        
+        doUpdateUI(status: status, state: state)
+    }
+    
+    func doUpdateUI(status: StatusMO, state: StatusState) {
         self.statusState = state
         
         let account = status.account
         self.accountID = account.id
         updateUI(account: account)
-        updateUIForPreferences(account: account)
+        updateUIForPreferences(account: account, status: status)
         
         attachmentsView.updateUI(status: status)
         attachmentsView.isAccessibilityElement = status.attachments.count > 0
@@ -213,18 +219,19 @@ class BaseStatusTableViewCell: UITableViewCell {
         }
     }
     
-    @objc func preferencesChanged() {
+    @objc private func preferencesChanged() {
         guard let mastodonController = mastodonController,
             let account = mastodonController.persistentContainer.account(for: accountID),
             let status = mastodonController.persistentContainer.status(for: statusID) else { return }
-        updateUIForPreferences(account: account)
-        updateStatusIconsForPreferences(status)
+        updateUIForPreferences(account: account, status: status)
     }
     
-    func updateUIForPreferences(account: AccountMO) {
+    func updateUIForPreferences(account: AccountMO, status: StatusMO) {
         avatarImageView.layer.cornerRadius = Preferences.shared.avatarStyle.cornerRadius(for: avatarImageView)
         displayNameLabel.updateForAccountDisplayName(account: account)
         attachmentsView.contentHidden = Preferences.shared.blurAllMedia || (mastodonController.persistentContainer.status(for: statusID)?.sensitive ?? false)
+        
+        updateStatusIconsForPreferences(status)
     }
     
     func updateStatusIconsForPreferences(_ status: StatusMO) {
diff --git a/Tusker/Views/Status/ConversationMainStatusTableViewCell.swift b/Tusker/Views/Status/ConversationMainStatusTableViewCell.swift
index 43d9f382..e33cd339 100644
--- a/Tusker/Views/Status/ConversationMainStatusTableViewCell.swift
+++ b/Tusker/Views/Status/ConversationMainStatusTableViewCell.swift
@@ -38,10 +38,9 @@ class ConversationMainStatusTableViewCell: BaseStatusTableViewCell {
         contentTextView.defaultFont = .systemFont(ofSize: 18)
     }
     
-    override func updateUI(statusID: String, state: StatusState) {
-        super.updateUI(statusID: statusID, state: state)
-        guard let status = mastodonController.persistentContainer.status(for: statusID) else { fatalError() }
-
+    override func doUpdateUI(status: StatusMO, state: StatusState) {
+        super.doUpdateUI(status: status, state: state)
+        
         var timestampAndClientText = ConversationMainStatusTableViewCell.dateFormatter.string(from: status.createdAt)
         if let application = status.applicationName {
             timestampAndClientText += " • \(application)"
@@ -63,8 +62,8 @@ class ConversationMainStatusTableViewCell: BaseStatusTableViewCell {
         profileAccessibilityElement.accessibilityLabel = account.displayNameWithoutCustomEmoji
     }
     
-    override func updateUIForPreferences(account: AccountMO) {
-        super.updateUIForPreferences(account: account)
+    override func updateUIForPreferences(account: AccountMO, status: StatusMO) {
+        super.updateUIForPreferences(account: account, status: status)
 
         favoriteAndReblogCountStackView.isHidden = !Preferences.shared.showFavoriteAndReblogCounts
     }
diff --git a/Tusker/Views/Status/TimelineStatusTableViewCell.swift b/Tusker/Views/Status/TimelineStatusTableViewCell.swift
index 367f2429..1964d3b0 100644
--- a/Tusker/Views/Status/TimelineStatusTableViewCell.swift
+++ b/Tusker/Views/Status/TimelineStatusTableViewCell.swift
@@ -68,10 +68,9 @@ class TimelineStatusTableViewCell: BaseStatusTableViewCell {
         }
     }
     
-    override func updateUI(statusID: String, state: StatusState) {
-        guard var status = mastodonController.persistentContainer.status(for: statusID) else { fatalError("Missing cached status \(statusID)") }
-
-        let realStatusID: String
+    override func doUpdateUI(status: StatusMO, state: StatusState) {
+        var status = status
+        
         if let rebloggedStatus = status.reblog {
             reblogStatusID = statusID
             rebloggerID = status.account.id
@@ -79,25 +78,24 @@ class TimelineStatusTableViewCell: BaseStatusTableViewCell {
             updateRebloggerLabel(reblogger: status.account)
             
             status = rebloggedStatus
-            realStatusID = rebloggedStatus.id
+            statusID = rebloggedStatus.id
         } else {
             reblogStatusID = nil
             rebloggerID = nil
             reblogLabel.isHidden = true
-            realStatusID = statusID
         }
         
-        super.updateUI(statusID: realStatusID, state: state)
-
-        updateTimestamp()
+        super.doUpdateUI(status: status, state: state)
+        
+        doUpdateTimestamp(status: status)
         
         let pinned = showPinned && (status.pinned ?? false)
         timestampLabel.isHidden = pinned
         pinImageView.isHidden = !pinned
     }
     
-    @objc override func preferencesChanged() {
-        super.preferencesChanged()
+    override func updateUIForPreferences(account: AccountMO, status: StatusMO) {
+        super.updateUIForPreferences(account: account, status: status)
         
         if let rebloggerID = rebloggerID,
             let reblogger = mastodonController.persistentContainer.account(for: rebloggerID) {
@@ -121,12 +119,16 @@ class TimelineStatusTableViewCell: BaseStatusTableViewCell {
         replyImageView.isHidden = !Preferences.shared.showIsStatusReplyIcon || !showReplyIndicator || status.inReplyToID == nil
     }
     
-    func updateTimestamp() {
+    private func updateTimestamp() {
         // if the mastodonController is nil (i.e. the delegate is nil), then the screen this cell was a part of has been deallocated
         // so we bail out immediately, since there's nothing to update
         guard let mastodonController = mastodonController else { return }
         guard let status = mastodonController.persistentContainer.status(for: statusID) else { fatalError("Missing cached status \(statusID!)") }
         
+        doUpdateTimestamp(status: status)
+    }
+    
+    private func doUpdateTimestamp(status: StatusMO) {
         timestampLabel.text = status.createdAt.timeAgoString()
         timestampLabel.accessibilityLabel = TimelineStatusTableViewCell.relativeDateFormatter.localizedString(for: status.createdAt, relativeTo: Date())