Bugfixes

- Disable cell animations for huge changes
- Updating a cell keeps the old position whenever possible
- Async `didChangeDateFilter`
- Fixes bug where saving a recording would persist entries again
- Small changes to `TimeFormat`, `AlertDeleteLogs` and `binTreeIndex()`

main/Common Classes/FilterPipeline.swift

@@ -17,6 +17,8 @@ class FilterPipeline<T> {
 	private var display: PipelineSorting<T>!
 	private(set) weak var delegate: FilterPipelineDelegate?
 	
+	private var cellAnimations: Bool = true
+	
 	required init(withDelegate: FilterPipelineDelegate) {
 		delegate = withDelegate
 	}
@@ -39,6 +41,8 @@ class FilterPipeline<T> {
 	/// - Returns: Index in `dataSource` and found object or `nil` if no matching item found.
 	/// - Complexity: O(*n*), where *n* is the length of the `dataSource`.
 	func dataSourceGet(where predicate: ((T) -> Bool)) -> (index: Int, object: T)? {
+		// TODO: use sorted dataSource for binary lookup?
+		//       would require to shift filter and sorting indices for every new element
 		guard let i = dataSource.firstIndex(where: predicate) else {
 			return nil
 		}
@@ -166,6 +170,20 @@ class FilterPipeline<T> {
 	
 	// MARK: data updates
 	
+	/// Disable individual cell updates (update, move, insert & remove actions)
+	func pauseCellAnimations(if condition: Bool) {
+		cellAnimations = delegate?.tableView.isFrontmost ?? false && !condition
+	}
+	
+	/// Allow individual cell updates (update, move, insert & remove actions) if tableView `isFrontmost`
+	/// - Parameter reloadTable: If `true` and cell animations are disabled, perform `tableView.reloadData()`
+	func continueCellAnimations(reloadTable: Bool = false) {
+		if !cellAnimations {
+			cellAnimations = true
+			if reloadTable { delegate?.tableView.reloadData() }
+		}
+	}
+	
 	/// Add new element to the original `dataSource` and immediately apply filter and sorting.
 	/// - Complexity: O((*m*+1) log *n*), where *m* is the number of filters and *n* the number of elements in each filter.
 	func addNew(_ obj: T) {
@@ -176,7 +194,7 @@ class FilterPipeline<T> {
 		}
 		// survived all filters
 		let displayIndex = display.insertNew(index)
-		delegate?.tableView.safeInsertRow(displayIndex, with: .left)
+		if cellAnimations { delegate?.tableView.safeInsertRow(displayIndex, with: .left) }
 	}
 	
 	/// Update element at `index` in the original `dataSource` and immediately re-apply filter and sorting.
@@ -190,21 +208,22 @@ class FilterPipeline<T> {
 		let oldPos = display.deleteOld(index)
 		dataSource[index] = obj
 		guard status.display else {
-			if let old = oldPos { delegate?.tableView.safeDeleteRows([old]) }
+			if cellAnimations, oldPos != -1 { delegate?.tableView.safeDeleteRows([oldPos]) }
 			return
 		}
-		let newPos = display.insertNew(index)
-		if let old = oldPos {
-			if old == newPos {
-				delegate?.tableView.safeReloadRow(old)
+		let newPos = display.insertNew(index, previousIndex: oldPos)
+		guard cellAnimations else { return }
+		if oldPos == -1 {
+			delegate?.tableView.safeInsertRow(newPos, with: .left)
+		} else {
+			if oldPos == newPos {
+				delegate?.tableView.safeReloadRow(oldPos)
 			} else {
-				delegate?.tableView.safeMoveRow(old, to: newPos)
+				delegate?.tableView.safeMoveRow(oldPos, to: newPos)
 				if delegate?.tableView.isFrontmost ?? false {
 					delegate?.rowNeedsUpdate(newPos)
 				}
 			}
-		} else {
-			delegate?.tableView.safeInsertRow(newPos, with: .left)
 		}
 	}
 	
@@ -221,7 +240,7 @@ class FilterPipeline<T> {
 			filter.shiftRemove(indices: sorted)
 		}
 		let indices = display.shiftRemove(indices: sorted)
-		delegate?.tableView.safeDeleteRows(indices)
+		if cellAnimations { delegate?.tableView.safeDeleteRows(indices) }
 	}
 }
 
@@ -368,20 +387,29 @@ class PipelineSorting<T> {
 	}
 	
 	/// Add new element and automatically sort according to predicate
-	/// - Parameter index: Index of the element position in the original `dataSource`
+	/// - Parameters:
+	///   - index: Index of the element position in the original `dataSource`
+	///   - prev: If greater than `0`, try re-insert at the same position.
 	/// - Returns: Index in the projection
 	/// - Complexity: O(log *n*), where *n* is the length of the `projection`.
-	@discardableResult fileprivate func insertNew(_ index: Int) -> Int {
-		projection.binTreeInsert(index, compare: comperator)
+	@discardableResult fileprivate func insertNew(_ index: Int, previousIndex prev: Int = -1) -> Int {
+		if prev >= 0, prev < projection.count {
+			if (prev == 0 || !comperator(index, projection[prev - 1])), !comperator(projection[prev], index) {
+				// If element can be inserted at the same position without resorting, do that
+				projection.insert(index, at: prev)
+				return prev
+			}
+		}
+		return projection.binTreeInsert(index, compare: comperator)
 	}
 	
 	/// Remove element from projection
 	/// - Parameter index: Index of the element position in the original `dataSource`
-	/// - Returns: Index in the projection or `nil` if element did not exist
+	/// - Returns: Index in the projection or `-1` if element did not exist
 	/// - Complexity: O(*n*), where *n* is the length of the `projection`.
-	fileprivate func deleteOld(_ index: Int) -> Int? {
+	fileprivate func deleteOld(_ index: Int) -> Int {
 		guard let i = projection.firstIndex(of: index) else {
-			return nil
+			return -1
 		}
 		projection.remove(at: i)
 		return i

main/Data Source/GroupedDomainDataSource.swift

@@ -52,10 +52,10 @@ class GroupedDomainDataSource {
 		sync.pause()
 		if let affectedDomain = notification?.object as? String {
 			partiallyReloadFromSource(affectedDomain)
-			sync.start()
+			sync.continue()
 		} else {
 			pipeline.reload(fromSource: true, whenDone: {
-				sync.start()
+				sync.continue()
 				refreshControl?.endRefreshing()
 			})
 		}
@@ -86,11 +86,14 @@ class GroupedDomainDataSource {
 	
 	/// Callback fired when background sync added new entries to the list. (`NotifySyncInsert` notification)
 	@objc private func syncInsert(_ notification: Notification) {
+		sync.pause()
+		defer { sync.continue() }
 		let range = notification.object as! SQLiteRowRange
 		guard let latest = AppDB?.dnsLogsGrouped(range: range, parentDomain: parent) else {
 			assertionFailure("NotifySyncInsert fired with empty range")
 			return
 		}
+		pipeline.pauseCellAnimations(if: latest.count > 14)
 		for x in latest {
 			if let (i, obj) = pipeline.dataSourceGet(where: { $0.domain == x.domain }) {
 				pipeline.update(obj + x, at: i)
@@ -101,16 +104,19 @@ class GroupedDomainDataSource {
 			}
 			tsLatest = max(tsLatest, x.lastModified)
 		}
+		pipeline.continueCellAnimations(reloadTable: true)
 	}
 	
 	/// Callback fired when background sync removed old entries from the list. (`NotifySyncRemove` notification)
 	@objc private func syncRemove(_ notification: Notification) {
+		sync.pause()
+		defer { sync.continue() }
 		let range = notification.object as! SQLiteRowRange
 		guard let outdated = AppDB?.dnsLogsGrouped(range: range, parentDomain: parent),
 			outdated.count > 0 else {
-				assertionFailure("NotifySyncRemove fired with empty range")
 				return
 		}
+		pipeline.pauseCellAnimations(if: outdated.count > 14)
 		var listOfDeletes: [Int] = []
 		for x in outdated {
 			guard let (i, obj) = pipeline.dataSourceGet(where: { $0.domain == x.domain }) else {
@@ -124,6 +130,7 @@ class GroupedDomainDataSource {
 			}
 		}
 		pipeline.remove(indices: listOfDeletes.sorted())
+		pipeline.continueCellAnimations(reloadTable: true)
 	}
 }
 
@@ -144,11 +151,12 @@ extension GroupedDomainDataSource {
 				return // nothing has changed
 			}
 			db.vacuum()
-			NotifyLogHistoryReset.postAsyncMain(domain) // calls deleteReloadFromSource(:)
+			NotifyLogHistoryReset.postAsyncMain(domain) // calls partiallyReloadFromSource(:)
 		}
 	}
 	
 	/// Reload a single data source entry. Callback fired by `reloadFromSource()`
+	/// Only useful if `affectedFQDN` currently exists in `dataSource`. Can either update or remove entry.
 	private func partiallyReloadFromSource(_ affectedFQDN: String) {
 		let affectedParent = affectedFQDN.extractDomain()
 		guard parent == nil || parent == affectedParent else {
@@ -159,20 +167,14 @@ extension GroupedDomainDataSource {
 			// can only happen if delete sheet is open while background sync removed the element
 			return
 		}
-		var removeOld = true
-		if let new = AppDB?.dnsLogsGrouped(since: sync.tsEarliest, upto: tsLatest, matchingDomain: affected, parentDomain: parent) {
-			assert(new.count < 2)
-			for var x in new {
-				x.options = DomainFilter[x.domain]
-				if old.object.domain == x.domain {
-					pipeline.update(x, at: old.index)
-					removeOld = false
-				} else {
-					pipeline.addNew(x)
-				}
-			}
+		if var updated = AppDB?.dnsLogsGrouped(since: sync.tsEarliest, upto: tsLatest,
+											   matchingDomain: affected, parentDomain: parent)?.first {
+			assert(old.object.domain == updated.domain)
+			updated.options = DomainFilter[updated.domain]
+			pipeline.update(updated, at: old.index)
+		} else {
+			pipeline.remove(indices: [old.index])
 		}
-		if removeOld { pipeline.remove(indices: [old.index]) }
 	}
 }
 

main/Data Source/RecordingsDB.swift

@@ -14,7 +14,10 @@ enum RecordingsDB {
 	static func list() -> [Recording] { AppDB?.recordingGetAll() ?? [] }
 	
 	/// Copy log entries from generic `heap` table  to recording specific `recLog` table
-	static func persist(_ r: Recording) { AppDB?.recordingLogsPersist(r) }
+	static func persist(_ r: Recording) {
+		sync.syncNow() // persist changes in cache before copying recording details
+		AppDB?.recordingLogsPersist(r)
+	}
 	
 	/// Get list of domains that occured during the recording
 	static func details(_ r: Recording) -> [RecordLog] {

main/Data Source/SyncUpdate.swift

@@ -11,34 +11,45 @@ class SyncUpdate {
 		timer = Timer.repeating(interval, call: #selector(periodicUpdate), on: self)
 	}
 	
+	@objc private func periodicUpdate() { if paused == 0 { syncNow() } }
+	
 	@objc private func didChangeDateFilter() {
 		let lastXFilter = Pref.DateFilter.lastXMinTimestamp() ?? 0
-		if tsEarliest < lastXFilter {
-			if let excess = AppDB?.dnsLogsRowRange(between: tsEarliest, and: lastXFilter) {
-				NotifySyncRemove.post(excess)
+		let before = tsEarliest
+		tsEarliest = lastXFilter
+		if before < lastXFilter {
+			DispatchQueue.global().async {
+				if let excess = AppDB?.dnsLogsRowRange(between: before, and: lastXFilter) {
+					NotifySyncRemove.postAsyncMain(excess)
+				}
 			}
-		} else if tsEarliest > lastXFilter {
-			if let missing = AppDB?.dnsLogsRowRange(between: lastXFilter, and: tsEarliest) {
-				NotifySyncInsert.post(missing)
+		} else if before > lastXFilter {
+			DispatchQueue.global().async {
+				if let missing = AppDB?.dnsLogsRowRange(between: lastXFilter, and: before) {
+					NotifySyncInsert.postAsyncMain(missing)
+				}
 			}
 		}
-		tsEarliest = lastXFilter
 	}
 	
+	func start() { paused = 0 }
 	func pause() { paused += 1 }
-	func start() { if paused > 0 { paused -= 1 } }
+	func `continue`() { if paused > 0 { paused -= 1 } }
 	
-	@objc private func periodicUpdate() {
-		guard paused == 0, let db = AppDB else { return }
-		if let inserted = db.dnsLogsPersist() { // move cache -> heap
+	func syncNow() {
+		self.pause() // reduce concurrent load
+		
+		if let inserted = AppDB?.dnsLogsPersist() { // move cache -> heap
 			NotifySyncInsert.post(inserted)
 		}
 		if let lastXFilter = Pref.DateFilter.lastXMinTimestamp(), tsEarliest < lastXFilter {
-			if let removed = db.dnsLogsRowRange(between: tsEarliest, and: lastXFilter) {
+			if let removed = AppDB?.dnsLogsRowRange(between: tsEarliest, and: lastXFilter) {
 				NotifySyncRemove.post(removed)
 			}
 			tsEarliest = lastXFilter
 		}
 		// TODO: periodic hard delete old logs (will reset rowids!)
+		
+		self.continue()
 	}
 }

main/Data Source/TestDataSource.swift

@@ -11,7 +11,8 @@ class TestDataSource {
 		QLog.Debug("SQLite path: \(URL.internalDB())")
 		
 		let deleted = db.dnsLogsDelete("test.com", strict: false)
-		QLog.Debug("Deleting \(deleted) rows matching 'test.com'")
+		try? db.run(sql: "DELETE FROM cache;")
+		QLog.Debug("Deleting \(deleted) rows matching 'test.com' (+ \(db.numberOfChanges) in cache)")
 		
 		QLog.Debug("Writing 33 test logs")
 		pStmt = try! db.logWritePrepare()

main/Extensions/AlertSheet.swift

@@ -43,7 +43,7 @@ func AskAlert(title: String?, text: String?, buttonText: String = "Continue", bu
 ///   - buttons: Default: `[]`
 ///   - lastIsDestructive: Default: `false`
 ///   - cancelButtonText: Default: `"Dismiss"`
-func BottomAlert(title: String?, text: String?, buttons: [String] = [], lastIsDestructive: Bool = false, cancelButtonText: String = "Dismiss", callback: @escaping (_ index: Int?) -> Void) -> UIAlertController {
+func BottomAlert(title: String?, text: String?, buttons: [String] = [], lastIsDestructive: Bool = false, cancelButtonText: String = "Cancel", callback: @escaping (_ index: Int?) -> Void) -> UIAlertController {
 	let alert = UIAlertController(title: title, message: text, preferredStyle: .actionSheet)
 	for (i, btn) in buttons.enumerated() {
 		let dangerous = (lastIsDestructive && i + 1 == buttons.count)
@@ -54,21 +54,13 @@ func BottomAlert(title: String?, text: String?, buttons: [String] = [], lastIsDe
 }
 
 func AlertDeleteLogs(_ domain: String, latest: Timestamp, success: @escaping (_ tsMin: Timestamp) -> Void) -> UIAlertController {
-	let sinceNow = Timestamp.now() - latest
-	var buttons = ["Last 5 minutes", "Last 15 minutes", "Last hour", "Last 24 hours", "Delete everything"]
-	var times: [Timestamp] = [300, 900, 3600, 86400]
-	while times.count > 0, times[0] < sinceNow {
-		buttons.removeFirst()
-		times.removeFirst()
-	}
-	return BottomAlert(title: "Delete logs", text: "Delete logs for domain '\(domain)'", buttons: buttons, lastIsDestructive: true, cancelButtonText: "Cancel") {
-		guard let idx = $0 else {
-			return
-		}
-		if idx >= times.count {
-			success(0)
-		} else {
-			success(Timestamp.now() - times[idx])
+	let minutesPassed = (Timestamp.now() - latest) / 60
+	let times: [Int] = [5, 15, 60, 1440].compactMap { minutesPassed < $0 ? $0 : nil }
+	let fmt = TimeFormat(.full, allowed: [.hour, .minute])
+	let labels = times.map { "Last " + (fmt.from(minutes: $0) ?? "?") }
+	return BottomAlert(title: "Delete logs", text: "Delete logs for domain '\(domain)'", buttons: labels + ["Delete everything"], lastIsDestructive: true) {
+		if let i = $0 {
+			success(i < times.count ? Timestamp.past(minutes: times[i]) : 0)
 		}
 	}
 }

main/Extensions/Array.swift

@@ -19,10 +19,13 @@ extension Array {
 	
 	/// Binary tree search operation.
 	/// - Warning: Array must be sorted already.
-	/// - Parameter mustExist: Determine whether to return low index or `nil` if element is missing.
+	/// - Parameters:
+	///   - mustExist: Determine whether to return low index or `nil` if element is missing.
+	///   - first: If `true`, keep searching for first matching element.
 	/// - Returns: Index or `nil` (only  if `mustExist = true` and element does not exist).
 	/// - Complexity: O(log *n*), where *n* is the length of the array.
-	func binTreeIndex(of element: Element, compare fn: CompareFn, mustExist: Bool = false) -> Int? {
+	func binTreeIndex(of element: Element, compare fn: CompareFn, mustExist: Bool = false, findFirst: Bool = false) -> Int? {
+		var found = false
 		var lo = 0, hi = self.count - 1
 		while lo <= hi {
 			let mid = (lo + hi)/2
@@ -31,10 +34,17 @@ extension Array {
 			} else if fn(element, self[mid]) {
 				hi = mid - 1
 			} else {
-				return mid
+				if !findFirst { return mid } // exit early if we dont care about first index
+				hi = mid - 1
+				found = true
 			}
 		}
-		return mustExist ? nil : lo // not found, would be inserted at position lo
+		return (mustExist && !found) ? nil : lo // not found, would be inserted at position lo
+	}
+	
+	/// Binary tree lookup whether element exists. Performs `binTreeIndex(of:compare:mustExist:)` internally.
+	func binTreeExists(_ element: Element, compare fn: CompareFn) -> Bool {
+		binTreeIndex(of: element, compare: fn, mustExist: true) != nil
 	}
 	
 	/// Binary tree  insert operation

main/Extensions/Time.swift

@@ -39,7 +39,27 @@ extension Timer {
 	}
 }
 
+// MARK: - TimeFormat
+
 struct TimeFormat {
+	private var formatter: DateComponentsFormatter
+	
+	/// Init new formatter with exactly 1 unit count. E.g., `61 min -> 1 hr`
+	/// - Parameter allowed: Default: `[.day, .hour, .minute, .second]`
+	init(_ style: DateComponentsFormatter.UnitsStyle, allowed: NSCalendar.Unit = [.day, .hour, .minute, .second]) {
+		formatter = DateComponentsFormatter()
+		formatter.maximumUnitCount = 1
+		formatter.allowedUnits = allowed
+		formatter.unitsStyle = style
+	}
+	
+	/// Formatted duration string, e.g., `20 min` or `7 days`
+	func from(days: Int = 0, hours: Int = 0, minutes: Int = 0, seconds: Int = 0) -> String? {
+		formatter.string(from: DateComponents(day: days, hour: hours, minute: minutes, second: seconds))
+	}
+	
+	// MARK: static
+	
 	/// Time string with format `HH:mm`
 	static func from(_ duration: Timestamp) -> String {
 		String(format: "%02d:%02d", duration / 60, duration % 60)
@@ -59,16 +79,4 @@ struct TimeFormat {
 	static func since(_ date: Date, millis: Bool = false) -> String {
 		from(Date().timeIntervalSince(date), millis: millis)
 	}
-	
-	/// Formatted duration string, e.g., `20 min` or `7 days`
-	/// - Parameters:
-	///   - minutes: Duration in minutes
-	///   - style: Default: `.short`
-	static func short(minutes: Int, style: DateComponentsFormatter.UnitsStyle = .short) -> String? {
-		let dcf = DateComponentsFormatter()
-		dcf.maximumUnitCount = 1
-		dcf.allowedUnits = [.day, .hour, .minute]
-		dcf.unitsStyle = style
-		return dcf.string(from: DateComponents(minute: minutes))
-	}
 }

main/Recordings/VCEditRecording.swift

@@ -35,7 +35,8 @@ class VCEditRecording: UIViewController, UITextFieldDelegate, UITextViewDelegate
 	// MARK: Save & Cancel Buttons
 	
 	@IBAction func didTapSave(_ sender: UIBarButtonItem) {
-		if deleteOnCancel { // aka newly created
+		let newlyCreated = deleteOnCancel
+		if newlyCreated {
 			// if remains true, `viewDidDisappear` will delete the record
 			deleteOnCancel = false
 		}
@@ -44,7 +45,9 @@ class VCEditRecording: UIViewController, UITextFieldDelegate, UITextViewDelegate
 		record.notes = (inputNotes.text == "") ? nil : inputNotes.text
 		dismiss(animated: true) {
 			RecordingsDB.update(self.record)
-			RecordingsDB.persist(self.record)
+			if newlyCreated {
+				RecordingsDB.persist(self.record)
+			}
 		}
 	}
 	

main/Recordings/VCRecordings.swift

@@ -38,6 +38,7 @@ class VCRecordings: UIViewController, UINavigationControllerDelegate {
 	}
 	
 	func navigationController(_ nav: UINavigationController, didShow vc: UIViewController, animated: Bool) {
+		// TODO: use interactive animation handler to dynamically animate "new recording" view
 		hideNewRecording(isRootVC: (vc == nav.viewControllers.first), didShow: true)
 	}
 	

main/Requests/TVCDomains.swift

@@ -117,7 +117,7 @@ class TVCDomains: UITableViewController, UISearchBarDelegate, FilterPipelineDele
 		case .LastXMin: // most recent
 			let lastXMin = Pref.DateFilter.LastXMin
 			if lastXMin == 0 { fallthrough }
-			self.filterButtonDetail.title = TimeFormat.short(minutes: lastXMin, style: .abbreviated)
+			self.filterButtonDetail.title = TimeFormat(.abbreviated).from(minutes: lastXMin)
 			self.filterButton.image = UIImage(named: "filter-filled")
 		default:
 			self.filterButtonDetail.title = ""

main/Requests/VCDateFilter.swift

@@ -54,7 +54,7 @@ class VCDateFilter: UIViewController, UIGestureRecognizerDelegate {
 		sender.value = Float(i) / 9
 		if sender.tag != durationTimes[i] {
 			sender.tag = durationTimes[i]
-			durationLabel.text = (sender.tag == 0 ? "Off" : TimeFormat.short(minutes: sender.tag))
+			durationLabel.text = (sender.tag == 0 ? "Off" : TimeFormat(.short).from(minutes: sender.tag))
 		}
 	}