From dbb7784198de5139765ed5cd39df622f55f27fb7 Mon Sep 17 00:00:00 2001
From: Sindre Sorhus <sindresorhus@gmail.com>
Date: Sat, 24 Feb 2018 23:08:38 +0700
Subject: [PATCH] Show progress in the Dock icon

---
 Gifski/AppDelegate.swift | 122 +++++++++++++++++++++++++++++++++++++++
 Gifski/Info.plist        |   6 +-
 Gifski/util.swift        |  30 ++++++++++
 3 files changed, 154 insertions(+), 4 deletions(-)

diff --git a/Gifski/AppDelegate.swift b/Gifski/AppDelegate.swift
index 0f0cb70f..3bf2470e 100644
--- a/Gifski/AppDelegate.swift
+++ b/Gifski/AppDelegate.swift
@@ -1,6 +1,125 @@
 import Cocoa
 import ProgressKit
 
+/// TODO: Fade the progress-bar in on the first progress events
+/// TODO: I will make this a separate SPM package soon
+final class DockIconProgress {
+	private static let appIcon = NSApp.applicationIconImage!
+	private static var previousProgressValue: Double = 0
+	private static var progressObserver: NSKeyValueObservation?
+
+	private static var dockImageView: NSImageView = {
+		let dockImageView = NSImageView()
+		NSApp.dockTile.contentView = dockImageView
+		return dockImageView
+	}()
+
+	static var progress: Progress? {
+		didSet {
+			if let progress = progress {
+				progressObserver = progress.observe(\.fractionCompleted, options: .new) { object, _ in
+					progressValue = object.fractionCompleted
+				}
+			}
+		}
+	}
+
+	static var progressValue: Double = 0 {
+		didSet {
+			if previousProgressValue == 0 || (progressValue - previousProgressValue).magnitude > 0.001 {
+				previousProgressValue = progressValue
+				updateDockIcon()
+			}
+		}
+	}
+
+	enum ProgressStyle {
+		case bar
+		/// TODO: Make `color` optional when https://github.com/apple/swift-evolution/blob/master/proposals/0155-normalize-enum-case-representation.md is shipping in Swift
+		case circle(radius: Double, color: NSColor)
+		case custom(drawHandler: (_ rect: CGRect) -> Void)
+	}
+
+	static var style: ProgressStyle = .bar
+
+	/// TODO: Make the progress smoother by also animating the steps between each call to `updateDockIcon()`
+	private static func updateDockIcon() {
+		DispatchQueue.global(qos: .utility).async {
+			/// TODO: If the `progressValue` is 1, draw the full circle, then schedule another draw in n milliseconds to hide it
+			let icon = (0..<1).contains(self.progressValue) ? self.draw() : appIcon
+			DispatchQueue.main.async {
+				/// TODO: Make this better by drawing in the `contentView` directly instead of using an image
+				dockImageView.image = icon
+				NSApp.dockTile.display()
+			}
+		}
+	}
+
+	private static func draw() -> NSImage {
+		return NSImage(size: appIcon.size, flipped: false) { dstRect in
+			NSGraphicsContext.current?.imageInterpolation = .high
+			self.appIcon.draw(in: dstRect)
+
+			switch self.style {
+			case .bar:
+				self.drawProgressBar(dstRect)
+			case let .circle(radius, color):
+				self.drawProgressCircle(dstRect, radius: radius, color: color)
+			case let .custom(drawingHandler):
+				drawingHandler(dstRect)
+			}
+
+			return true
+		}
+	}
+
+	private static func drawProgressBar(_ dstRect: CGRect) {
+		func roundedRect(_ rect: CGRect) {
+			NSBezierPath(roundedRect: rect, cornerRadius: rect.height / 2).fill()
+		}
+
+		let bar = CGRect(x: 0, y: 20, width: dstRect.width, height: 10)
+		NSColor.white.withAlphaComponent(0.8).set()
+		roundedRect(bar)
+
+		let barInnerBg = bar.insetBy(dx: 0.5, dy: 0.5)
+		NSColor.black.withAlphaComponent(0.8).set()
+		roundedRect(barInnerBg)
+
+		var barProgress = bar.insetBy(dx: 1, dy: 1)
+		barProgress.size.width = barProgress.width * CGFloat(self.progressValue)
+		NSColor.white.set()
+		roundedRect(barProgress)
+	}
+
+	private static func drawProgressCircle(_ dstRect: CGRect, radius: Double, color: NSColor) {
+		guard let cgContext = NSGraphicsContext.current?.cgContext else {
+			return
+		}
+
+		let path = NSBezierPath()
+		let startAngle: CGFloat = 90
+		let endAngle = startAngle - (360 * CGFloat(self.progressValue))
+		path.appendArc(
+			withCenter: dstRect.center,
+			radius: CGFloat(radius),
+			startAngle: startAngle,
+			endAngle: endAngle,
+			clockwise: true
+		)
+
+		let arc = CAShapeLayer()
+		arc.path = path.cgPath
+		arc.lineCap = kCALineCapRound
+		arc.fillColor = nil
+		arc.strokeColor = color.cgColor
+		arc.lineWidth = 4
+		arc.cornerRadius = 3
+		arc.render(in: cgContext)
+	}
+}
+
+
 extension NSColor {
 	static let appTheme = NSColor(named: NSColor.Name("Theme"))!
 }
@@ -189,5 +308,8 @@ final class AppDelegate: NSObject, NSApplicationDelegate {
 			frameRate: choosenFrameRate
 		)
 		progress?.publish()
+
+		DockIconProgress.progress = progress
+		DockIconProgress.style = .circle(radius: 55, color: .appTheme)
 	}
 }
diff --git a/Gifski/Info.plist b/Gifski/Info.plist
index 4d6d4371..89885c07 100644
--- a/Gifski/Info.plist
+++ b/Gifski/Info.plist
@@ -31,16 +31,14 @@
 	<string>APPL</string>
 	<key>CFBundleShortVersionString</key>
 	<string>1.0.0</string>
-	<key>CFBundleURLTypes</key>
-	<array>
-		<dict/>
-	</array>
 	<key>CFBundleVersion</key>
 	<string>1</string>
 	<key>LSApplicationCategoryType</key>
 	<string>public.app-category.photography</string>
 	<key>LSMinimumSystemVersion</key>
 	<string>$(MACOSX_DEPLOYMENT_TARGET)</string>
+	<key>MDItemKeywords</key>
+	<string>gif,convert,video</string>
 	<key>NSMainNibFile</key>
 	<string>MainMenu</string>
 	<key>NSPrincipalClass</key>
diff --git a/Gifski/util.swift b/Gifski/util.swift
index 5c5f4ae6..88c55657 100644
--- a/Gifski/util.swift
+++ b/Gifski/util.swift
@@ -55,6 +55,36 @@ class SSView: NSView {
 }
 
 
+extension NSBezierPath {
+	/// UIKit polyfill
+	var cgPath: CGPath {
+		let path = CGMutablePath()
+		var points = [CGPoint](repeating: .zero, count: 3)
+
+		for i in 0..<elementCount {
+			let type = element(at: i, associatedPoints: &points)
+			switch type {
+			case .moveToBezierPathElement:
+				path.move(to: points[0])
+			case .lineToBezierPathElement:
+				path.addLine(to: points[0])
+			case .curveToBezierPathElement:
+				path.addCurve(to: points[2], control1: points[0], control2: points[1])
+			case .closePathBezierPathElement:
+				path.closeSubpath()
+			}
+		}
+
+		return path
+	}
+	
+	/// UIKit polyfill
+	convenience init(roundedRect rect: CGRect, cornerRadius: CGFloat) {
+		self.init(roundedRect: rect, xRadius: cornerRadius, yRadius: cornerRadius)
+	}
+}
+
+
 extension AVAssetImageGenerator {
 	func generateCGImagesAsynchronously(forTimePoints timePoints: [CMTime], completionHandler: @escaping AVAssetImageGeneratorCompletionHandler) {
 		let times = timePoints.map { NSValue(time: $0) }