feat: add support for scrolling

README.md

@@ -85,9 +85,9 @@ The mouse cursor can be moved using the following markup: `<m:[x1,y1,]x2,y2[:dur
 
 Example usage:
 
-- `<m:400,400:0.5>`: Move mouse cursor from current position to 400, 400 over 0.5 seconds
-- `<m:400,400,0,0:2>`: Move mouse cursor from 400, 400 position to 0, 0 over 2 seconds
-- `<m:400,400>`: Move mouse cursor to 400, 400 instantly
+- `<m:400,400:0.5>`: Move mouse cursor from current position to 400, 400 over 0.5 seconds.
+- `<m:400,400,0,0:2>`: Move mouse cursor from 400, 400 position to 0, 0 over 2 seconds.
+- `<m:400,400>`: Move mouse cursor to 400, 400 instantly.
 
 #### Mouse click
 
@@ -98,8 +98,8 @@ A mouse click can be activated using the following markup: `<m:button[:clicks]>`
 
 Example usage:
 
-- `<m:right>`: Right mouse click at the current mouse location
-- `<m:left:2>`: Double click the left button at the current mouse location
+- `<m:right>`: Right mouse click at the current mouse location.
+- `<m:left:2>`: Double click the left button at the current mouse location.
 
 #### Mouse drag
 
@@ -114,8 +114,22 @@ The structure argument structure is similar to moving the mouse cursor.
 
 Example usage:
 
-- `<d:400,400:0.5>`: Drag the mouse using the left mouse button from current position to 400, 400 over 0.5 seconds
-- `<d:400,400,0,0:2:right>`: Drag the mouse using the right mouse button from 400, 400 position to 0, 0 over 2 seconds
+- `<d:400,400:0.5>`: Drag the mouse using the left mouse button from current position to 400, 400 over 0.5 seconds.
+- `<d:400,400,0,0:2:right>`: Drag the mouse using the right mouse button from 400, 400 position to 0, 0 over 2 seconds.
+
+#### Mouse scrolling
+
+A mouse scroll can be initiated with: `<s:x,y[:duration]>`
+
+- `x` is required and controls horizontal scrolling. Positive values scroll to the right, while negative values scroll to the left.
+- `y` is required and controls vertical scrolling. Positive values scroll down, while negative values scroll up.
+- `duration` is optional and determines the number of seconds (supports partial seconds) that should be used to drag the mouse (larger number means slower movement). Defaults to `0`.
+
+Example usage:
+
+- `<s:0,400:0.5>`: Scrolls down 400 pixels over 0.5 seconds.
+- `<s:0,-100:0.2>`: Scrolls up 400 pixels over 0.2 seconds.
+- `<s:100,0>`: Scrolls 100 pixel to the right instantly.
 
 ### Pauses
 

Sources/SendKeysLib/Commands/Command.swift

@@ -5,14 +5,15 @@ public enum CommandType {
     case mouseMove
     case mouseClick
     case mouseDrag
+    case mouseScroll
     case continuation
 }
 
 public struct Command: Equatable {
     let type: CommandType
-    let arguments: [String]
+    let arguments: [String?]
 
-    public init(_ type: CommandType, _ arguments: [String]) {
+    public init(_ type: CommandType, _ arguments: [String?]) {
         self.type = type
         self.arguments = arguments
     }

Sources/SendKeysLib/Commands/CommandExecutor.swift

@@ -20,6 +20,8 @@ public class CommandExecutor: CommandExecutorProtocol {
             executeMouseClick(command)
         case .mouseDrag:
             executeMouseDrag(command)
+        case .mouseScroll:
+            executeMouseScroll(command)
         default:
             fatalError("Unrecognized command type \(command.type)")
         }
@@ -29,22 +31,22 @@ public class CommandExecutor: CommandExecutorProtocol {
         var modifiers: [String] = []
 
         if command.arguments.count > 1 {
-            modifiers = command.arguments[1].components(separatedBy: ",")
+            modifiers = command.arguments[1]!.components(separatedBy: ",")
         }
 
-        try! keyPresser.pressKey(key: command.arguments[0], modifiers: modifiers)
+        try! keyPresser.pressKey(key: command.arguments[0]!, modifiers: modifiers)
     }
 
     private func executePause(_ command: Command) {
-        Sleeper.sleep(seconds: Double(command.arguments[0])!)
+        Sleeper.sleep(seconds: Double(command.arguments[0]!)!)
     }
 
     private func executeMouseMove(_ command: Command) {
-        let x1 = Double(command.arguments[0])!
-        let y1 = Double(command.arguments[1])!
-        let x2 = Double(command.arguments[2])!
-        let y2 = Double(command.arguments[3])!
-        let duration: TimeInterval = Double(command.arguments[4])!
+        let x1 = Double(command.arguments[0]!)!
+        let y1 = Double(command.arguments[1]!)!
+        let x2 = Double(command.arguments[2]!)!
+        let y2 = Double(command.arguments[3]!)!
+        let duration: TimeInterval = Double(command.arguments[4]!)!
 
         mouseController.move(
             start: CGPoint(x: x1, y: y1),
@@ -54,23 +56,34 @@ public class CommandExecutor: CommandExecutorProtocol {
     }
 
     private func executeMouseClick(_ command: Command) {
-        let button = command.arguments[0]
-        let clicks = Int(command.arguments[1])!
+        let button = command.arguments[0]!
+        let clicks = Int(command.arguments[1]!)!
 
         try! mouseController.click(
             CGPoint(x: -1, y: -1),
             button: getMouseButton(button: button),
             clickCount: clicks
         )
     }
+
+    private func executeMouseScroll(_ command: Command) {
+        let x = Int(command.arguments[0]!) ?? 0
+        let y = Int(command.arguments[1]!) ?? 0
+        let duration = Double(command.arguments[2] ?? "0") ?? 0
+
+        mouseController.scroll(
+            CGPoint(x: x, y: y),
+            duration
+        )
+    }
 
     private func executeMouseDrag(_ command: Command) {
-        let x1 = Double(command.arguments[0])!
-        let y1 = Double(command.arguments[1])!
-        let x2 = Double(command.arguments[2])!
-        let y2 = Double(command.arguments[3])!
-        let duration: TimeInterval = Double(command.arguments[4])!
-        let button = command.arguments[5]
+        let x1 = Double(command.arguments[0]!)!
+        let y1 = Double(command.arguments[1]!)!
+        let x2 = Double(command.arguments[2]!)!
+        let y2 = Double(command.arguments[3]!)!
+        let duration: TimeInterval = Double(command.arguments[4]!)!
+        let button = command.arguments[5]!
 
         try! mouseController.drag(
             start: CGPoint(x: x1, y: y1),

Sources/SendKeysLib/Commands/CommandsIterator.swift

@@ -12,6 +12,7 @@ public class CommandsIterator: IteratorProtocol {
         MouseMoveCommandMatcher(),
         MouseClickCommandMatcher(),
         MouseDragCommandMatcher(),
+        MouseScrollCommandMatcher(),
         DefaultCommandMatcher()
     ]
 

Sources/SendKeysLib/Commands/CommandsProcessor.swift

@@ -38,7 +38,7 @@ public class CommandsProcessor {
                 shouldDefaultPause = false
             } else if command.type == .stickyPause {
                 shouldDefaultPause = false
-                defaultPause = Double(command.arguments[0])!
+                defaultPause = Double(command.arguments[0]!)!
             } else if shouldDefaultPause {
                 executeCommand(getDefaultPauseCommand())
                 shouldDefaultPause = true

Sources/SendKeysLib/Commands/MouseScrollCommandMatcher.swift

@@ -0,0 +1,19 @@
+import Foundation
+
+public class MouseScrollCommandMatcher: CommandMatcher {
+    public init() {
+        super.init(try! NSRegularExpression(pattern: "\\<s:(-?\\d+),(-?\\d+)(:([.\\d]+))?\\>"))
+    }
+
+    override public func createCommand(_ arguments: [String?]) -> Command {
+        let x = arguments[1]
+        let y = arguments[2]
+        let duration = arguments[4]
+
+        return Command(.mouseScroll, [
+            x,
+            y,
+            duration
+        ])
+    }
+}

Sources/SendKeysLib/MouseController.swift

@@ -1,6 +1,11 @@
 import Foundation
 
 class MouseController {
+    enum ScrollAxis {
+        case horizontal
+        case vertical
+    }
+
     let animationRefreshInterval: TimeInterval = 0.01
 
     func move(start: CGPoint, end: CGPoint, duration: TimeInterval) {
@@ -62,6 +67,40 @@ class MouseController {
         upEvent?.post(tap: CGEventTapLocation.cghidEventTap)
     }
 
+    func scroll(_ delta: CGPoint, _ duration: TimeInterval) {
+        var scrolledX: Int = 0;
+        var scrolledY: Int = 0;
+
+        let animator = Animator(duration, animationRefreshInterval, { progress in
+            if delta.x != 0 {
+                let amount = Int((Double(delta.x) * progress) - Double(scrolledX))
+                scrolledX += amount
+
+                self.scrollBy(amount, .horizontal)
+            }
+            if delta.y != 0 {
+                let amount = Int((Double(delta.y) * progress) - Double(scrolledY))
+                scrolledY += amount
+
+                self.scrollBy(amount, .vertical)
+            }
+        })
+
+        animator.animate()
+    }
+
+    func scrollBy(_ amount: Int, _ axis: ScrollAxis) {
+        if #available(OSX 10.13, *) {
+            let event = CGEvent(scrollWheelEvent2Source: nil, units: .pixel, wheelCount: 1, wheel1: 0, wheel2: 0, wheel3: 0)
+            let field = axis == .vertical ? CGEventField.scrollWheelEventPointDeltaAxis1 : CGEventField.scrollWheelEventPointDeltaAxis2
+
+            event?.setIntegerValueField(field, value: Int64(amount * -1))
+            event?.post(tap: CGEventTapLocation.cghidEventTap)
+        } else {
+            fatalError("Scrolling is only available on 10.13 or later")
+        }
+    }
+
     func getLocation() -> CGPoint? {
         let event = CGEvent(source: nil);
         return event?.location

Tests/SendKeysTests/CommandIteratorTests.swift

@@ -217,6 +217,42 @@ final class CommandIteratorTests: XCTestCase {
             ])
     }
 
+    func testParsesMouseScroll() throws {
+        let commands = getCommands(CommandsIterator("<s:0,10>"))
+        XCTAssertEqual(
+            commands,
+            [
+                Command(CommandType.mouseScroll, ["0", "10", nil])
+            ])
+    }
+
+    func testParsesMouseScrollWithNegativeAmount() throws {
+        let commands = getCommands(CommandsIterator("<s:-100,10>"))
+        XCTAssertEqual(
+            commands,
+            [
+                Command(CommandType.mouseScroll, ["-100", "10", nil])
+            ])
+    }
+
+    func testParsesMouseScrollWithDuration() throws {
+        let commands = getCommands(CommandsIterator("<s:0,10:0.5>"))
+        XCTAssertEqual(
+            commands,
+            [
+                Command(CommandType.mouseScroll, ["0", "10", "0.5"])
+            ])
+    }
+
+    func testParsesMouseScrollWithNegativeAmountAndDuration() throws {
+        let commands = getCommands(CommandsIterator("<s:0,-10:0.5>"))
+        XCTAssertEqual(
+            commands,
+            [
+                Command(CommandType.mouseScroll, ["0", "-10", "0.5"])
+            ])
+    }
+
     private func getCommands(_ iterator: CommandsIterator) -> [Command] {
         var commands: [Command] = []