Get the Dock position, size and hidden state in a Cocoa app

DockInfo.swift

//
//  DockInfo.swift
//
//  Created by Wessley Roche on 28/11/2016.
//

import Foundation

enum WBDockPosition: Int {
	case bottom = 0
	case left = 1
	case right = 2
}

func getDockPosition() -> WBDockPosition {
	if NSScreen.main()!.visibleFrame.origin.y == 0 {
		if NSScreen.main()!.visibleFrame.origin.x == 0 {
			return .right
		} else {
			return .left
		}
	} else {
		return .bottom
	}
}

func getDockSize() -> CGFloat {
	let dockPosition = getDockPosition()
	switch dockPosition {
	case .right:
		let size = NSScreen.main()!.frame.width - NSScreen.main()!.visibleFrame.width
		return size
	case .left:
		let size = NSScreen.main()!.visibleFrame.origin.x
		return size
	case .bottom:
		let size = NSScreen.main()!.visibleFrame.origin.y
		return size
	}
}

func isDockHidden() -> Bool {
	let dockSize = getDockSize()
	
	if dockSize < 25 {
		return true
	} else {
		return false
	}
}

There is also
defaults read com.apple.dock "orientation"
or the private API CoreDockGetOrientationAndPinning if that is something you can use. https://stackoverflow.com/questions/7717258/find-the-location-of-the-dock-programmatically