From 5acce87995db91934474845fe93cb3dae189ec53 Mon Sep 17 00:00:00 2001
From: Nate Weaver <wevah@derailer.org>
Date: Fri, 10 Jul 2020 13:33:25 -0500
Subject: [PATCH] Mac: Make shift-space scroll up even when the detail view
 doesn't have focus

Issue #969.
---
 Mac/MainWindow/Detail/DetailViewController.swift    |  8 ++++++++
 Mac/MainWindow/Detail/DetailWebViewController.swift | 10 ++++++++++
 Mac/MainWindow/MainWindowController.swift           | 13 +++++++++++++
 Shared/Resources/GlobalKeyboardShortcuts.plist      | 10 ++++++++++
 4 files changed, 41 insertions(+)

diff --git a/Mac/MainWindow/Detail/DetailViewController.swift b/Mac/MainWindow/Detail/DetailViewController.swift
index c7d2c2497..63e632b21 100644
--- a/Mac/MainWindow/Detail/DetailViewController.swift
+++ b/Mac/MainWindow/Detail/DetailViewController.swift
@@ -66,9 +66,17 @@ final class DetailViewController: NSViewController, WKUIDelegate {
 		currentWebViewController.canScrollDown(callback)
 	}
 
+	func canScrollUp(_ callback: @escaping (Bool) -> Void) {
+		currentWebViewController.canScrollUp(callback)
+	}
+
 	override func scrollPageDown(_ sender: Any?) {
 		currentWebViewController.scrollPageDown(sender)
 	}
+
+	override func scrollPageUp(_ sender: Any?) {
+		currentWebViewController.scrollPageUp(sender)
+	}
 	
 	// MARK: - Navigation
 	
diff --git a/Mac/MainWindow/Detail/DetailWebViewController.swift b/Mac/MainWindow/Detail/DetailWebViewController.swift
index e77101f9d..e75b8f71a 100644
--- a/Mac/MainWindow/Detail/DetailWebViewController.swift
+++ b/Mac/MainWindow/Detail/DetailWebViewController.swift
@@ -167,9 +167,19 @@ final class DetailWebViewController: NSViewController, WKUIDelegate {
 		}
 	}
 
+	func canScrollUp(_ completion: @escaping (Bool) -> Void) {
+		fetchScrollInfo { (scrollInfo) in
+			completion(scrollInfo?.canScrollUp ?? false)
+		}
+	}
+
 	override func scrollPageDown(_ sender: Any?) {
 		webView.scrollPageDown(sender)
 	}
+
+	override func scrollPageUp(_ sender: Any?) {
+		webView.scrollPageUp(sender)
+	}
 }
 
 // MARK: - WKScriptMessageHandler
diff --git a/Mac/MainWindow/MainWindowController.swift b/Mac/MainWindow/MainWindowController.swift
index eab97ca16..e79300644 100644
--- a/Mac/MainWindow/MainWindowController.swift
+++ b/Mac/MainWindow/MainWindowController.swift
@@ -264,6 +264,19 @@ class MainWindowController : NSWindowController, NSUserInterfaceValidations {
 		}
 	}
 
+	@IBAction func scrollUp(_ sender: Any?) {
+		guard let detailViewController = detailViewController else {
+			return
+		}
+		detailViewController.canScrollUp { (canScroll) in
+			if (canScroll) {
+				NSCursor.setHiddenUntilMouseMoves(true)
+				detailViewController.scrollPageUp(sender)
+			}
+		}
+
+	}
+
 	@IBAction func openArticleInBrowser(_ sender: Any?) {
 		if let link = currentLink {
 			Browser.open(link, invertPreference: NSApp.currentEvent?.modifierFlags.contains(.shift) ?? false)
diff --git a/Shared/Resources/GlobalKeyboardShortcuts.plist b/Shared/Resources/GlobalKeyboardShortcuts.plist
index c6288be02..4c2626cbe 100644
--- a/Shared/Resources/GlobalKeyboardShortcuts.plist
+++ b/Shared/Resources/GlobalKeyboardShortcuts.plist
@@ -10,6 +10,16 @@
 		<key>action</key>
 		<string>scrollOrGoToNextUnread:</string>
 	</dict>
+	<dict>
+		<key>title</key>
+		<string>Scroll or Go to Next Unread</string>
+		<key>key</key>
+		<string>[space]</string>
+		<key>shiftModifier</key>
+		<true/>
+		<key>action</key>
+		<string>scrollUp:</string>
+	</dict>
 	<dict>
 		<key>title</key>
 		<string>Go to Previous Unread</string>