macos: window-position-x/y works with window-width/height (#9313)

Fixes #9132

We were processing our window size defaults separate from our window
position and the result was that you'd get some incorrect behavior.
Unify the logic more to fix the positioning.

Note there is room to improve this further, I think that all initial
positioning could go into the controller completely. But I wanted to
minimize the diff for a backport.

macos/Sources/Features/Terminal/TerminalController.swift

@@ -531,7 +531,7 @@ class TerminalController: BaseTerminalController, TabGroupCloseCoordinator.Contr
             frame.origin.x = max(screen.frame.origin.x, min(frame.origin.x, screen.frame.maxX - newWidth))
             frame.origin.y = max(screen.frame.origin.y, min(frame.origin.y, screen.frame.maxY - newHeight))
 
-            return frame
+            return adjustForWindowPosition(frame: frame, on: screen)
         }
 
         guard let initialFrame else { return nil }
@@ -549,7 +549,30 @@ class TerminalController: BaseTerminalController, TabGroupCloseCoordinator.Contr
         frame.origin.x = max(screen.frame.origin.x, min(frame.origin.x, screen.frame.maxX - newWidth))
         frame.origin.y = max(screen.frame.origin.y, min(frame.origin.y, screen.frame.maxY - newHeight))
 
-        return frame
+        return adjustForWindowPosition(frame: frame, on: screen)
+    }
+    
+    /// Adjusts the given frame for the configured window position.
+    func adjustForWindowPosition(frame: NSRect, on screen: NSScreen) -> NSRect {
+        guard let x = derivedConfig.windowPositionX else { return frame }
+        guard let y = derivedConfig.windowPositionY else { return frame }
+
+        // Convert top-left coordinates to bottom-left origin using our utility extension
+        let origin = screen.origin(
+            fromTopLeftOffsetX: CGFloat(x),
+            offsetY: CGFloat(y),
+            windowSize: frame.size)
+        
+        // Clamp the origin to ensure the window stays fully visible on screen
+        var safeOrigin = origin
+        let vf = screen.visibleFrame
+        safeOrigin.x = min(max(safeOrigin.x, vf.minX), vf.maxX - frame.width)
+        safeOrigin.y = min(max(safeOrigin.y, vf.minY), vf.maxY - frame.height)
+        
+        // Return our new origin
+        var result = frame
+        result.origin = safeOrigin
+        return result
     }
 
     /// This is called anytime a node in the surface tree is being removed.
@@ -1362,12 +1385,16 @@ class TerminalController: BaseTerminalController, TabGroupCloseCoordinator.Contr
         let macosWindowButtons: Ghostty.MacOSWindowButtons
         let macosTitlebarStyle: String
         let maximize: Bool
+        let windowPositionX: Int16?
+        let windowPositionY: Int16?
 
         init() {
             self.backgroundColor = Color(NSColor.windowBackgroundColor)
             self.macosWindowButtons = .visible
             self.macosTitlebarStyle = "system"
             self.maximize = false
+            self.windowPositionX = nil
+            self.windowPositionY = nil
         }
 
         init(_ config: Ghostty.Config) {
@@ -1375,6 +1402,8 @@ class TerminalController: BaseTerminalController, TabGroupCloseCoordinator.Contr
             self.macosWindowButtons = config.macosWindowButtons
             self.macosTitlebarStyle = config.macosTitlebarStyle
             self.maximize = config.maximize
+            self.windowPositionX = config.windowPositionX
+            self.windowPositionY = config.windowPositionY
         }
     }
 }

macos/Sources/Features/Terminal/Window Styles/TerminalWindow.swift

@@ -84,8 +84,7 @@ class TerminalWindow: NSWindow {
         // fallback to original centering behavior
         setInitialWindowPosition(
             x: config.windowPositionX,
-            y: config.windowPositionY,
-            windowDecorations: config.windowDecorations)
+            y: config.windowPositionY)
 
         // If our traffic buttons should be hidden, then hide them
         if config.macosWindowButtons == .hidden {
@@ -463,7 +462,7 @@ class TerminalWindow: NSWindow {
         return derivedConfig.backgroundColor.withAlphaComponent(alpha)
     }
 
-    private func setInitialWindowPosition(x: Int16?, y: Int16?, windowDecorations: Bool) {
+    private func setInitialWindowPosition(x: Int16?, y: Int16?) {
         // If we don't have an X/Y then we try to use the previously saved window pos.
         guard let x, let y else {
             if (!LastWindowPosition.shared.restore(self)) {
@@ -479,19 +478,14 @@ class TerminalWindow: NSWindow {
             return
         }
 
-        // Convert top-left coordinates to bottom-left origin using our utility extension
-        let origin = screen.origin(
-            fromTopLeftOffsetX: CGFloat(x),
-            offsetY: CGFloat(y),
-            windowSize: frame.size)
+        // We have an X/Y, use our controller function to set it up.
+        guard let terminalController else {
+            center()
+            return
+        }
         
-        // Clamp the origin to ensure the window stays fully visible on screen
-        var safeOrigin = origin
-        let vf = screen.visibleFrame
-        safeOrigin.x = min(max(safeOrigin.x, vf.minX), vf.maxX - frame.width)
-        safeOrigin.y = min(max(safeOrigin.y, vf.minY), vf.maxY - frame.height)
-        
-        setFrameOrigin(safeOrigin)
+        let frame = terminalController.adjustForWindowPosition(frame: frame, on: screen)
+        setFrameOrigin(frame.origin)
     }
 
     private func hideWindowButtons() {