OS X window management in MacRuby

window.rb

framework "Carbon"
framework "ApplicationServices"
framework "AppKit"

class Application
  def self.active
    info = NSWorkspace.sharedWorkspace.activeApplication
    pid = info["NSApplicationProcessIdentifier"]
    new pid
  end

  def self.all
    NSWorkspace.sharedWorkspace.runningApplications.map{|app|
      new app.processIdentifier
    }
  end
  
  def initialize pid
    @pid = pid
    @app = AXUIElementCreateApplication pid
  end

  def focused_window
    window = Pointer.new(:id)
    err = AXUIElementCopyAttributeValue(@app,
                                        NSAccessibilityFocusedWindowAttribute,
                                        window)
    Window.new window[0]
  end

  def windows
    windows = Pointer.new(:id)
    err = AXUIElementCopyAttributeValue(@app,
                                        KAXWindowsAttribute,
                                        windows)
    (windows[0] || []).map{|w| Window.new w} || []
  end

  def title
    title = Pointer.new(:id)
    err = AXUIElementCopyAttributeValue(@app, "AXTitle", title)
    title[0]
  end
end

class Window
  attr_accessor :window
  
  def self.active
    Application.active.focused_window
  end

  def self.all
    Application.all.map(&:windows).flatten
  end

  def initialize window
    @window = window
  end

  def position
    position_ref = Pointer.new(:id)
    err = AXUIElementCopyAttributeValue(@window,
                                        NSAccessibilityPositionAttribute,
                                        position_ref)
    pos_pt = Pointer.new("{CGPoint=dd}")
    err = AXValueGetValue(position_ref[0], KAXValueCGPointType, pos_pt)
    pos_pt[0]
  end

  def position= a
    x, y = a
    position = Pointer.new("{CGPoint=dd}")
    position.assign(NSPoint.new(x, y))
    position_ref = AXValueCreate(KAXValueCGPointType, position)
    AXUIElementSetAttributeValue(@window,
                                 NSAccessibilityPositionAttribute,
                                 position_ref)
  end

  def size
    size_ref = Pointer.new(:id)
    err = AXUIElementCopyAttributeValue(@window,
                                        NSAccessibilitySizeAttribute,
                                        size_ref)
    size_pt = Pointer.new("{CGSize=dd}")
    err = AXValueGetValue(size_ref[0], KAXValueCGSizeType, size_pt)
    size_pt[0]
  end

  def size= a
    w, h =a
    size = Pointer.new("{CGSize=dd}")
    size.assign(NSSize.new(w,h))
    size_ref = AXValueCreate(KAXValueCGSizeType, size)
    AXUIElementSetAttributeValue(@window,
                                 NSAccessibilitySizeAttribute,
                                 size_ref)
  end

  def title
    title = Pointer.new(:id)
    err = AXUIElementCopyAttributeValue(@window, "AXTitle", title)
    title[0]
  end
end