From 86cdb4676a537195d50c3a891e1676c835edb54c Mon Sep 17 00:00:00 2001
From: Justin Mazzocchi <2831158+jzzocc@users.noreply.github.com>
Date: Fri, 5 Feb 2021 20:23:05 -0800
Subject: [PATCH] Fix account header jumping

---
 View Controllers/TableViewController.swift | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/View Controllers/TableViewController.swift b/View Controllers/TableViewController.swift
index 779e876..fa9c1d4 100644
--- a/View Controllers/TableViewController.swift	
+++ b/View Controllers/TableViewController.swift	
@@ -321,7 +321,9 @@ private extension TableViewController {
         }
         .store(in: &cancellables)
 
-        viewModel.updates.sink { [weak self] in self?.update($0) }.store(in: &cancellables)
+        viewModel.updates.receive(on: DispatchQueue.main)
+            .sink { [weak self] in self?.update($0) }
+            .store(in: &cancellables)
 
         viewModel.events.receive(on: DispatchQueue.main)
             .sink { [weak self] in self?.handle(event: $0) }
@@ -370,15 +372,23 @@ private extension TableViewController {
 
     func update(_ update: CollectionUpdate) {
         let positionMaintenanceOffset: CGFloat
+        let preUpdateContentOffsetY = tableView.contentOffset.y
+        var setPreviousOffset = false
 
         if let itemId = update.maintainScrollPositionItemId,
            let indexPath = dataSource.indexPath(itemId: itemId) {
             positionMaintenanceOffset = tableView.rectForRow(at: indexPath).origin.y
-                - tableView.safeAreaInsets.top - tableView.contentOffset.y
+                - tableView.safeAreaInsets.top - preUpdateContentOffsetY
         } else {
             positionMaintenanceOffset = 0
         }
 
+        if let headerView = tableView.tableHeaderView,
+           let headerViewWindowFrame = view.window?.convert(headerView.frame, from: headerView),
+           headerViewWindowFrame.maxY > 0 {
+            setPreviousOffset = true
+        }
+
         self.dataSource.apply(update.sections.snapshot(), animatingDifferences: false) { [weak self] in
             guard let self = self else { return }
 
@@ -395,6 +405,8 @@ private extension TableViewController {
 
                 self.tableView.scrollToRow(at: indexPath, at: .top, animated: false)
                 self.tableView.contentOffset.y -= positionMaintenanceOffset
+            } else if setPreviousOffset {
+                self.tableView.contentOffset.y = preUpdateContentOffsetY
             }
         }
     }