Merge pull request #3329 from everhardt/feat-1844-scroll-mark-as-read

Add mark as read on scroll

Mac/MainWindow/Timeline/TimelineViewController+ContextualMenus.swift

@@ -111,6 +111,9 @@ private extension TimelineViewController {
 
 	func markArticles(_ articles: [Article], read: Bool) {
 		markArticles(articles, statusKey: .read, flag: read)
+		for article in articles {
+			articlesWithManuallyChangedReadStatus.insert(article)
+		}
 	}
 
 	func markArticles(_ articles: [Article], starred: Bool) {

Mac/MainWindow/Timeline/TimelineViewController.swift

@@ -70,6 +70,7 @@ final class TimelineViewController: NSViewController, UndoableCommandRunner, Unr
 				if showsSearchResults {
 					fetchAndReplaceArticlesAsync()
 				} else {
+					resetMarkAsReadOnScroll()
 					fetchAndReplaceArticlesSync()
 					if articles.count > 0 {
 						tableView.scrollRowToVisible(0)
@@ -138,6 +139,11 @@ final class TimelineViewController: NSViewController, UndoableCommandRunner, Unr
 	}
 
 	var undoableCommands = [UndoableCommand]()
+
+	var articlesWithManuallyChangedReadStatus: Set<Article> = Set()
+
+	private var isScrolling = false
+	
 	private var fetchSerialNumber = 0
 	private let fetchRequestQueue = FetchRequestQueue()
 	private var exceptionArticleFetcher: ArticleFetcher?
@@ -191,6 +197,10 @@ final class TimelineViewController: NSViewController, UndoableCommandRunner, Unr
 	private let keyboardDelegate = TimelineKeyboardDelegate()
 	private var timelineShowsSeparatorsObserver: NSKeyValueObservation?
 
+	private let scrollPositionQueue = CoalescingQueue(name: "Timeline Scroll Position", interval: 0.3, maxInterval: 1.0)
+
+	private var markBottomArticlesAsReadWorkItem: DispatchWorkItem?
+	
 	convenience init(delegate: TimelineDelegate) {
 		self.init(nibName: "TimelineTableView", bundle: nil)
 		self.delegate = delegate
@@ -223,6 +233,16 @@ final class TimelineViewController: NSViewController, UndoableCommandRunner, Unr
 			NotificationCenter.default.addObserver(self, selector: #selector(containerChildrenDidChange(_:)), name: .ChildrenDidChange, object: nil)
 			NotificationCenter.default.addObserver(self, selector: #selector(userDefaultsDidChange(_:)), name: UserDefaults.didChangeNotification, object: nil)
 
+			if let scrollView = self.tableView.enclosingScrollView {
+				scrollView.contentView.postsBoundsChangedNotifications = true
+				
+				NotificationCenter.default.addObserver(self, selector: #selector(scrollViewDidScroll(notification:)), name: NSView.boundsDidChangeNotification, object: scrollView.contentView)
+				
+				NotificationCenter.default.addObserver(self, selector: #selector(scrollViewWillStartLiveScroll(notification:)), name: NSScrollView.willStartLiveScrollNotification, object: scrollView)
+				NotificationCenter.default.addObserver(self, selector: #selector(scrollViewDidEndLiveScroll(notification:)), name: NSScrollView.didEndLiveScrollNotification, object: scrollView)
+
+			}
+
 			didRegisterForNotifications = true
 		}
 	}
@@ -281,6 +301,8 @@ final class TimelineViewController: NSViewController, UndoableCommandRunner, Unr
 	}
 	
 	func restoreState(from state: [AnyHashable : Any]) {
+		resetMarkAsReadOnScroll()
+		
 		guard let readArticlesFilterStateKeys = state[UserInfoKey.readArticlesFilterStateKeys] as? [[AnyHashable: AnyHashable]],
 			let readArticlesFilterStateValues = state[UserInfoKey.readArticlesFilterStateValues] as? [Bool] else {
 			return
@@ -324,6 +346,66 @@ final class TimelineViewController: NSViewController, UndoableCommandRunner, Unr
 		}
 	}
 	
+	@objc func scrollViewDidScroll(notification: Notification){
+		if isScrolling {
+			scrollPositionQueue.add(self, #selector(scrollPositionDidChange))
+		}
+	}
+	
+	@objc func scrollViewWillStartLiveScroll(notification: Notification){
+		isScrolling = true
+	}
+	
+	@objc func scrollViewDidEndLiveScroll(notification: Notification){
+		isScrolling = false
+	}
+	
+	@objc func scrollPositionDidChange(){
+		if !AppDefaults.shared.markArticlesAsReadOnScroll {
+			return
+		}
+		
+		// Mark all articles as read when the bottom of the feed is reached
+		let lastRowIndex = articles.count - 1
+		let atBottom = tableView.rows(in: tableView.visibleRect).contains(lastRowIndex)
+		
+		if atBottom && markBottomArticlesAsReadWorkItem == nil {
+			let task = DispatchWorkItem {
+				let articlesToMarkAsRead = self.articles.filter { !$0.status.read && !self.articlesWithManuallyChangedReadStatus.contains($0) }
+				
+				if articlesToMarkAsRead.isEmpty { return }
+				guard let undoManager = self.undoManager, let markReadCommand = MarkStatusCommand(initialArticles: articlesToMarkAsRead, markingRead: true, undoManager: undoManager) else {
+					return
+				}
+				self.runCommand(markReadCommand)
+				self.markBottomArticlesAsReadWorkItem = nil
+			}
+			
+			markBottomArticlesAsReadWorkItem = task
+			DispatchQueue.main.asyncAfter(deadline: .now() + 2, execute: task)
+		} else if !atBottom, let task = markBottomArticlesAsReadWorkItem {
+			task.cancel()
+			markBottomArticlesAsReadWorkItem = nil
+		}
+		
+		
+		// Mark articles scrolled out of sight at the top as read
+		let firstVisibleRowIndex = tableView.rows(in: tableView.visibleRect).location
+		let unreadArticlesScrolledAway = articles.articlesAbove(position: firstVisibleRowIndex).filter { !$0.status.read && !articlesWithManuallyChangedReadStatus.contains($0) }
+				
+		if unreadArticlesScrolledAway.isEmpty { return }
+
+		guard let undoManager = undoManager, let markReadCommand = MarkStatusCommand(initialArticles: unreadArticlesScrolledAway, markingRead: true, undoManager: undoManager) else {
+			return
+		}
+		runCommand(markReadCommand)
+	}
+	
+	func resetMarkAsReadOnScroll() {
+		articlesWithManuallyChangedReadStatus.removeAll()
+		markBottomArticlesAsReadWorkItem?.cancel()
+	}
+	
 	@IBAction func toggleStatusOfSelectedArticles(_ sender: Any?) {
 		guard !selectedArticles.isEmpty else {
 			return
@@ -345,6 +427,9 @@ final class TimelineViewController: NSViewController, UndoableCommandRunner, Unr
 			return
 		}
 		runCommand(markReadCommand)
+		for article in selectedArticles {
+			articlesWithManuallyChangedReadStatus.insert(article)
+		}
 	}
 	
 	@IBAction func markSelectedArticlesAsUnread(_ sender: Any?) {
@@ -352,6 +437,9 @@ final class TimelineViewController: NSViewController, UndoableCommandRunner, Unr
 			return
 		}
 		runCommand(markUnreadCommand)
+		for article in selectedArticles {
+			articlesWithManuallyChangedReadStatus.insert(article)
+		}
 	}
 
 	@IBAction func copy(_ sender: Any?) {
@@ -903,6 +991,7 @@ extension TimelineViewController: NSTableViewDelegate {
 			return
 		}
 		self.runCommand(markUnreadCommand)
+		articlesWithManuallyChangedReadStatus.insert(article)
 	}
 
 	private func toggleArticleStarred(_ article: Article) {