feat: display other spaces/minimized windows (closes #14)

Also closes #11 closes #45 closes #62

BREAKING CHANGE: this brings huge changes to core parts of the codebase. It introduces the use of private APIs that hopefully are should be compatible from macOS 10.12+, but I couldn't test them. I reviewed the whole codebase to clean and improve on performance and readability

alt-tab-macos/Info.plist

@@ -28,5 +28,7 @@
 	<string>NSApplication</string>
 	<key>LSUIElement</key>
 	<string>1</string>
+	<key>ATSApplicationFontsPath</key>
+	<string></string>
 </dict>
 </plist>

alt-tab-macos/api-wrappers/AXUIElement.swift

@@ -0,0 +1,83 @@
+import Cocoa
+import Foundation
+
+// This list of keys is not exhaustive; it contains only the values used by this app
+// full public list: ApplicationServices.HIServices.AXAttributeConstants.swift
+// Note that the String value is transformed by the getters (e.g. kAXWindowsAttribute -> AXWindows)
+enum AXAttributeKey: String {
+    case windows = "AXWindows"
+    case minimized = "AXMinimized"
+    case focusedWindow = "AXFocusedWindow"
+}
+
+extension AXUIElement {
+    func value<T>(_ key: AXAttributeKey, _ target: T, _ type: AXValueType) -> T? {
+        if let a = attribute(key, AXValue.self) {
+            var value = target
+            AXValueGetValue(a, type, &value)
+            return value
+        }
+        return nil
+    }
+
+    func attribute<T>(_ key: AXAttributeKey, _ type: T.Type) -> T? {
+        var value: AnyObject?
+        let result = AXUIElementCopyAttributeValue(self, key.rawValue as CFString, &value)
+        if result == .success, let value = value as? T {
+            return value
+        }
+        return nil
+    }
+
+    func cgId() -> CGWindowID {
+        var id = CGWindowID(0)
+        _AXUIElementGetWindow(self, &id)
+        return id
+    }
+
+    func focusedWindow() -> AXUIElement? {
+        return attribute(.focusedWindow, AXUIElement.self)
+    }
+
+    func windows() -> [AXUIElement]? {
+        return attribute(.windows, [AXUIElement].self)
+    }
+
+    func isMinimized() -> Bool {
+        return attribute(.minimized, Bool.self) == true
+    }
+
+    func focus(_ id: CGWindowID) {
+        var elementConnection = UInt32(0)
+        CGSGetWindowOwner(cgsMainConnectionId, id, &elementConnection)
+        var psn = ProcessSerialNumber()
+        CGSGetConnectionPSN(elementConnection, &psn)
+        _SLPSSetFrontProcessWithOptions(&psn, id, .userGenerated)
+        makeKeyWindow(psn, id)
+        AXUIElementPerformAction(self, kAXRaiseAction as CFString)
+    }
+
+    // The following function was ported from https://github.com/Hammerspoon/hammerspoon/issues/370#issuecomment-545545468
+    func makeKeyWindow(_ psn: ProcessSerialNumber, _ wid: CGWindowID) -> Void {
+        var wid_ = wid
+        var psn_ = psn
+
+        var bytes1 = [UInt8](repeating: 0, count: 0xf8)
+        bytes1[0x04] = 0xF8
+        bytes1[0x08] = 0x01
+        bytes1[0x3a] = 0x10
+
+        var bytes2 = [UInt8](repeating: 0, count: 0xf8)
+        bytes2[0x04] = 0xF8
+        bytes2[0x08] = 0x02
+        bytes2[0x3a] = 0x10
+
+        memcpy(&bytes1[0x3c], &wid_, MemoryLayout<UInt32>.size)
+        memset(&bytes1[0x20], 0xFF, 0x10)
+        memcpy(&bytes2[0x3c], &wid_, MemoryLayout<UInt32>.size)
+        memset(&bytes2[0x20], 0xFF, 0x10)
+
+        SLPSPostEventRecordTo(&psn_, &(UnsafeMutablePointer(mutating: UnsafePointer<UInt8>(bytes1)).pointee))
+        SLPSPostEventRecordTo(&psn_, &(UnsafeMutablePointer(mutating: UnsafePointer<UInt8>(bytes2)).pointee))
+    }
+}

alt-tab-macos/api-wrappers/CGWindow.swift

@@ -0,0 +1,36 @@
+import Cocoa
+import Foundation
+
+typealias CGWindow = [CGWindowKey.RawValue: Any]
+
+extension CGWindow {
+    static func windows(_ option: CGWindowListOption) -> [CGWindow] {
+        return CGWindowListCopyWindowInfo([.excludeDesktopElements, option], kCGNullWindowID) as! [CGWindow]
+    }
+
+    func value<T>(_ key: CGWindowKey, _ type: T.Type) -> T? {
+        return self[key.rawValue] as? T
+    }
+
+    // workaround: filtering this criteria seems to remove non-windows UI elements
+    func isNotMenubarOrOthers() -> Bool {
+        return value(.layer, Int.self) == 0
+    }
+
+    // workaround: some apps like chrome use a window to implement the search popover
+    func isReasonablyBig() -> Bool {
+        let windowBounds = CGRect(dictionaryRepresentation: value(.bounds, CFDictionary.self)!)!
+        return windowBounds.width > Preferences.minimumWindowSize && windowBounds.height > Preferences.minimumWindowSize
+    }
+}
+
+// This list of keys is not exhaustive; it contains only the values used by this app
+// full public list: CoreGraphics.CGWindow.swift
+enum CGWindowKey: String {
+    case number = "kCGWindowNumber"
+    case layer = "kCGWindowLayer"
+    case bounds = "kCGWindowBounds"
+    case ownerPID = "kCGWindowOwnerPID"
+    case ownerName = "kCGWindowOwnerName"
+    case name = "kCGWindowName"
+}

alt-tab-macos/api-wrappers/CGWindowID.swift

@@ -0,0 +1,32 @@
+import Cocoa
+import Foundation
+
+extension CGWindowID {
+    func AXUIElement(_ ownerPid: pid_t) -> AXUIElement? {
+        return AXUIElementCreateApplication(ownerPid).windows()?.first(where: { return $0.cgId() == self })
+    }
+
+    func AXUIElementOfOtherSpaceWindow(_ ownerPid: pid_t) -> AXUIElement? {
+        CGSAddWindowsToSpaces(cgsMainConnectionId, [self], [Spaces.currentSpaceId])
+        let axWindow = AXUIElement(ownerPid)
+        CGSRemoveWindowsFromSpaces(cgsMainConnectionId, [self], [Spaces.currentSpaceId])
+        return axWindow
+    }
+
+    func screenshot() -> CGImage? {
+        // CGSHWCaptureWindowList
+        var windowId_ = self
+        let options: CGSWindowCaptureOptions = [.captureIgnoreGlobalClipShape, .windowCaptureNominalResolution]
+        let list = CGSHWCaptureWindowList(cgsMainConnectionId, &windowId_, 1, options) as! [CGImage]
+        return list.first
+
+//        // CGWindowListCreateImage
+//        return CGWindowListCreateImage(.null, .optionIncludingWindow, self, [.boundsIgnoreFraming, .bestResolution])
+
+//        // CGSCaptureWindowsContentsToRectWithOptions
+//        var windowId_ = self
+//        var windowImage = CIContext(options: nil).createCGImage(CIImage.empty(), from: CIImage.empty().extent)!
+//        CGSCaptureWindowsContentsToRectWithOptions(cgsMainConnectionId, &windowId_, true, .zero, [.windowCaptureNominalResolution, .captureIgnoreGlobalClipShape], &windowImage)
+//        return windowImage
+    }
+}

alt-tab-macos/logic/Extensions.swift → alt-tab-macos/api-wrappers/HelperExtensions.swift

@@ -1,8 +1,8 @@
 import Foundation
 import Cocoa
 
-// add CGFloat constructor from String
 extension CGFloat {
+    // add CGFloat constructor from String
     init?(_ string: String) {
         guard let number = NumberFormatter().number(from: string) else {
             return nil
@@ -11,8 +11,8 @@ extension CGFloat {
     }
 }
 
-// add throw-on-nil method on Optional
 extension Optional {
+    // add throw-on-nil method on Optional
     func orThrow() throws -> Wrapped {
         switch self {
         case .some(let value):
@@ -24,8 +24,8 @@ extension Optional {
     }
 }
 
-// add String constructor from CGFloat that round up at 1 decimal
 extension String {
+    // add String constructor from CGFloat that round up at 1 decimal
     init?(_ cgFloat: CGFloat) {
         let formatter = NumberFormatter()
         formatter.maximumFractionDigits = 1
@@ -36,8 +36,8 @@ extension String {
     }
 }
 
-// add recursive lookup in subviews for specific type
 extension NSView {
+    // add recursive lookup in subviews for specific type
     func findNestedViews<T: NSView>(subclassOf: T.Type) -> [T] {
         return recursiveSubviews.compactMap { $0 as? T }
     }
@@ -47,8 +47,8 @@ extension NSView {
     }
 }
 
-// add convenience to NSError
 extension NSError {
+    // add convenience to NSError
     class func make(domain: String, message: String, code: Int = 9999) -> NSError {
         return NSError(
                 domain: domain,
@@ -57,3 +57,10 @@ extension NSError {
         )
     }
 }
+
+extension Collection {
+    // recursive flatMap
+    func joined() -> [Any] {
+        return flatMap { ($0 as? [Any])?.joined() ?? [$0] }
+    }
+}