Added preference to scroll past end of editor

- New preference for editor
- Refactored preference boolean actions slightly

CHANGELOG.md

@@ -7,6 +7,7 @@
 - Added RTL writing direction support in editor and preview
 - Added preference to show invisible characters
 - Added preference to show a toolbar on the window
+- Added preference to scroll past end of editor
 - Added preferences to sync scroll position between editor and preview
 - Added 9 new themes:
   - a11y-dark

Pine/Controllers/MarkdownViewController.swift

@@ -55,7 +55,7 @@ class MarkdownViewController: NSViewController, NSTextViewDelegate, HighlightDel
     NotificationCenter.receive(.appearanceChanged, instance: self, selector: #selector(generatePreview))
 
     // Setup notification observer for when scroll view scrolls
-    NotificationCenter.receive(.scrollViewScrolled, instance: self, selector: #selector(scrollViewDidScroll))
+    NotificationCenter.receive(.boundsDidChange, instance: self, selector: #selector(scrollViewDidScroll))
 
     // Setup a 200ms debouncer for generating the markdown preview
     debouncedGeneratePreview = Debouncer(delay: 0.2) {
@@ -120,7 +120,6 @@ class MarkdownViewController: NSViewController, NSTextViewDelegate, HighlightDel
     markdownTextView.insertionPointColor = .gray
     markdownTextView.isVerticallyResizable = true
     markdownTextView.isHorizontallyResizable = false
-    markdownTextView.textContainerInset = NSSize(width: 10.0, height: 10.0)
 
     if #available(OSX 10.12.2, *) {
       markdownTextView.touchBar = self.makeTouchBar()
@@ -133,11 +132,11 @@ class MarkdownViewController: NSViewController, NSTextViewDelegate, HighlightDel
     view.updateLayer()
     generatePreview()
     layoutManager.fontDidUpdate()
-    markdownTextView.isContinuousSpellCheckingEnabled = preferences[Preference.spellcheckEnabled]
+    markdownTextView.setOverscroll()
   }
 
   /// When the scroll view scrolls, sync the preview if enabled in preferences
-  @objc private func scrollViewDidScroll() {
+  @objc private func scrollViewDidScroll() {    
     guard
       preferences[Preference.syncEditorAndPreview],
       let documentView = scrollView.documentView

Pine/Extensions/Cocoa/NotificationCenter.swift

@@ -31,5 +31,6 @@ extension NotificationCenter {
 extension Notification.Name {
   static let preferencesChanged = Notification.Name("preferencesChanged")
   static let appearanceChanged = Notification.Name("appearanceChanged")
-  static let scrollViewScrolled = NSView.boundsDidChangeNotification
+  static let boundsDidChange = NSView.boundsDidChangeNotification
+  static let frameDidChange = NSView.frameDidChangeNotification
 }

Pine/Models/Preferences/Preferences.swift

@@ -23,6 +23,7 @@ enum Preference {
   static let syncEditorAndPreview = PreferenceKey<Bool>("syncEditorAndPreview", defaultValue: false)
   static let showToolbar = PreferenceKey<Bool>("showToolbar", defaultValue: false)
   static let showInvisibles = PreferenceKey<Bool>("showInvisibles", defaultValue: false)
+  static let scrollPastEnd = PreferenceKey<Bool>("scrollPastEnd", defaultValue: false)
 
   // Font options
   static let fontSize = PreferenceKey<CGFloat>("fontSize", defaultValue: 14)
@@ -79,6 +80,14 @@ class Preferences {
     defaults.setValue(value, forKey: preferenceKey.key)
   }
 
+  /// Given a boolean preference map, a key and value, set the value if found in the map
+  public func setFromBoolMap(_ map: BoolPreferenceMap, key: String, value: Bool) {
+    if let ext = map[key] {
+      self[ext] = value
+      NotificationCenter.send(.preferencesChanged)
+    }
+  }
+
   // MARK: - Dynamic preferences
 
   public var markdownExtensions: [MarkdownExtensions] {

Pine/Views/MarkdownTextView.swift

@@ -10,33 +10,26 @@ import Cocoa
 
 class MarkdownTextView: NSTextView {
 
+  private let CONTAINER_INSET: CGFloat = 10.0
+
+  private var overscroll: CGFloat = 0
   private var needsRecompletion: Bool = false
   private var partialAutocompleteWord: String?
 
   private lazy var autocompletionTask = Debouncer(delay: 0, callback: {
     [unowned self] in self.performCompletion()
   })
 
-  override func keyDown(with event: NSEvent) {
-    if let singleCharacter = event.characters?.first, preferences[Preference.autoPairSyntax] {
-      self.pair(character: singleCharacter)
+  override var isContinuousSpellCheckingEnabled: Bool {
+    get {
+      return preferences[Preference.spellcheckEnabled]
     }
 
-    super.keyDown(with: event)
-  }
-
-  override func insertText(_ string: Any, replacementRange: NSRange) {
-    super.insertText(string, replacementRange: replacementRange)
-    self.autocompletionTask.call()
+    set {}
   }
 
-  override func didChangeText() {
-    super.didChangeText()
-
-    if self.needsRecompletion {
-      self.needsRecompletion = false
-      self.autocompletionTask.call()
-    }
+  override var textContainerOrigin: NSPoint {
+    return NSPoint(x: CONTAINER_INSET, y: CONTAINER_INSET)
   }
 
   override var rangeForUserCompletion: NSRange {
@@ -61,6 +54,33 @@ class MarkdownTextView: NSTextView {
     return NSRange(location: location, length: cursorLocation - location)
   }
 
+  override func viewDidMoveToWindow() {
+    // Setup notification for when scrollview frame changes
+    NotificationCenter.receive(.frameDidChange, instance: self, selector: #selector(setOverscroll))
+  }
+
+  override func keyDown(with event: NSEvent) {
+    if let singleCharacter = event.characters?.first, preferences[Preference.autoPairSyntax] {
+      self.pair(character: singleCharacter)
+    }
+
+    super.keyDown(with: event)
+  }
+
+  override func insertText(_ string: Any, replacementRange: NSRange) {
+    super.insertText(string, replacementRange: replacementRange)
+    self.autocompletionTask.call()
+  }
+
+  override func didChangeText() {
+    super.didChangeText()
+
+    if self.needsRecompletion {
+      self.needsRecompletion = false
+      self.autocompletionTask.call()
+    }
+  }
+
   override func completions(
     forPartialWordRange charRange: NSRange,
     indexOfSelectedItem index: UnsafeMutablePointer<Int>
@@ -131,6 +151,22 @@ class MarkdownTextView: NSTextView {
     super.paste(sender)
   }
 
+  // MARK: - Public methods
+
+  @objc public func setOverscroll() {
+    guard
+      let font = self.font,
+      let scrollView = self.enclosingScrollView,
+      let lineHeight = layoutManager?.defaultLineHeight(for: font)
+    else { return }
+
+    let ratio: CGFloat = preferences[Preference.scrollPastEnd] ? 0.5 : 0
+
+    let inset = ratio * (scrollView.documentVisibleRect.height - lineHeight)
+
+    self.textContainerInset.height = max(floor(inset / 2), CONTAINER_INSET)
+  }
+
   // MARK: - Private helper methods
 
   private func pasteImages(_ images: [URL]) {

Pine/Views/Preferences/DocumentStackView.swift

@@ -36,10 +36,7 @@ class DocumentStackView: NSStackView, PreferenceStackView {
   // MARK: - Behavior preference actions
 
   @objc func behaviorPreferenceChanged(_ sender: NSButton) {
-    if let ext = behaviourMap[sender.title] {
-      preferences[ext] = sender.value
-      NotificationCenter.send(.preferencesChanged)
-    }
+    preferences.setFromBoolMap(behaviourMap, key: sender.title, value: sender.value)
   }
 
 }

Pine/Views/Preferences/EditorStackView.swift

@@ -14,6 +14,10 @@ class EditorStackView: NSStackView, PreferenceStackView, NSFontChanging {
     "Show invisibles": Preference.showInvisibles
   ]
 
+  private let behaviourMap: BoolPreferenceMap = [
+    "Scroll past end": Preference.scrollPastEnd
+  ]
+
   private func getAppearanceArea() -> NSStackView {
     let view = PreferencesStackView(name: "Appearance:")
 
@@ -26,6 +30,18 @@ class EditorStackView: NSStackView, PreferenceStackView, NSFontChanging {
     return view
   }
 
+  private func getBehaviorArea() -> NSStackView {
+    let view = PreferencesStackView(name: "Behavior:")
+
+    view.addBooleanArea(
+      target: self,
+      using: behaviourMap,
+      selector: #selector(behaviorPreferenceChanged)
+    )
+
+    return view
+  }
+
   private func getFontArea() -> NSStackView {
     let view = PreferencesStackView(name: "Font:")
 
@@ -44,17 +60,21 @@ class EditorStackView: NSStackView, PreferenceStackView, NSFontChanging {
   public func getViews() -> [NSView] {
     return [
       getAppearanceArea(),
+      getBehaviorArea(),
       getFontArea()
     ]
   }
 
-  // MARK: - Behavior preference actions
+  // MARK: - Appearance preference actions
 
   @objc func appearancePreferenceChanged(_ sender: NSButton) {
-    if let ext = appearanceMap[sender.title] {
-      preferences[ext] = sender.value
-      NotificationCenter.send(.preferencesChanged)
-    }
+    preferences.setFromBoolMap(appearanceMap, key: sender.title, value: sender.value)
+  }
+
+  // MARK: - Behavior preference actions
+
+  @objc func behaviorPreferenceChanged(_ sender: NSButton) {
+    preferences.setFromBoolMap(behaviourMap, key: sender.title, value: sender.value)
   }
 
   // MARK: - Font preference actions

Pine/Views/Preferences/MarkdownStackView.swift

@@ -95,28 +95,19 @@ class MarkdownStackView: NSStackView, PreferenceStackView {
   // MARK: - Behavior preference actions
 
   @objc func behaviourPreferenceChanged(_ sender: NSButton) {
-    if let ext = behaviourMap[sender.title] {
-      preferences[ext] = sender.value
-      NotificationCenter.send(.preferencesChanged)
-    }
+    preferences.setFromBoolMap(behaviourMap, key: sender.title, value: sender.value)
   }
 
   // MARK: - Autocomplete preference actions
 
   @objc func autocompletePreferenceChanged(_ sender: NSButton) {
-    if let ext = autocompleteMap[sender.title] {
-      preferences[ext] = sender.value
-      NotificationCenter.send(.preferencesChanged)
-    }
+    preferences.setFromBoolMap(autocompleteMap, key: sender.title, value: sender.value)
   }
 
   // MARK: - Markdown extension preference actions
 
   @objc func extensionPreferenceChanged(_ sender: NSButton) {
-    if let ext = extensionsMap[sender.title] {
-      preferences[ext] = sender.value
-      NotificationCenter.send(.preferencesChanged)
-    }
+    preferences.setFromBoolMap(extensionsMap, key: sender.title, value: sender.value)
   }
 
   // MARK: - Default application preference actions

Pine/Views/Preferences/UIStackView.swift

@@ -105,28 +105,19 @@ class UIStackView: NSStackView, PreferenceStackView {
   }
 
   @objc func appearancePreferenceChanged(_ sender: NSButton) {
-    if let ext = appearanceMap[sender.title] {
-      preferences[ext] = sender.value
-      NotificationCenter.send(.preferencesChanged)
-    }
+    preferences.setFromBoolMap(appearanceMap, key: sender.title, value: sender.value)
   }
 
   // MARK: - Window preference actions
 
   @objc func windowPreferenceChanged(_ sender: NSButton) {
-    if let ext = windowMap[sender.title] {
-      preferences[ext] = sender.value
-      NotificationCenter.send(.preferencesChanged)
-    }
+    preferences.setFromBoolMap(windowMap, key: sender.title, value: sender.value)
   }
 
   // MARK: - Behavior preference actions
 
   @objc func behaviorPreferenceChanged(_ sender: NSButton) {
-    if let ext = behaviorMap[sender.title] {
-      preferences[ext] = sender.value
-      NotificationCenter.send(.preferencesChanged)
-    }
+    preferences.setFromBoolMap(behaviorMap, key: sender.title, value: sender.value)
   }
 
 }