feat(wm): add alt-tab heuristics to wsr

This commit adds some rough heuristics to workspace_reconciliator which
should help with having the correct window focused after reconciliation
in the majority of, but probably not all, cases.

EnumWindows generally returns HWNDs according to z order, and a window
selected by alt-tab will almost always be put on the top of the z order.
Before sending a workspace_reconciliator::Notification, we store this
HWND along with an Instant and an AtomicBool telling us that we have a
candidate to focus after the workspace switch.

justfile

@@ -28,7 +28,6 @@ install:
     just install-target komorebi
 
 run:
-    just install-target komorebic
     cargo +stable run --bin komorebi --locked
 
 warn $RUST_LOG="warn":
@@ -44,7 +43,6 @@ trace $RUST_LOG="trace":
     just run
 
 deadlock $RUST_LOG="trace":
-    just install-komorebic
     cargo +stable run --bin komorebi --locked --features deadlock_detection
 
 docgen:

komorebi-core/src/arrangement.rs

@@ -26,7 +26,7 @@ pub trait Arrangement {
 }
 
 impl Arrangement for DefaultLayout {
-    #[allow(clippy::too_many_lines)]
+    #[allow(clippy::too_many_lines, clippy::cognitive_complexity)]
     fn calculate(
         &self,
         area: &Rect,
@@ -58,12 +58,13 @@ impl Arrangement for DefaultLayout {
                         layout.right += adjustment.right;
                     });
 
-                match layout_flip {
-                    Some(Axis::Horizontal | Axis::HorizontalAndVertical) => match len {
-                        2.. => columns_reverse(&mut layouts),
-                        _ => {}
-                    },
-                    _ => {}
+                if matches!(
+                    layout_flip,
+                    Some(Axis::Horizontal | Axis::HorizontalAndVertical)
+                ) {
+                    if let 2.. = len {
+                        columns_reverse(&mut layouts);
+                    }
                 }
 
                 layouts
@@ -82,12 +83,13 @@ impl Arrangement for DefaultLayout {
                         layout.right += adjustment.right;
                     });
 
-                match layout_flip {
-                    Some(Axis::Vertical | Axis::HorizontalAndVertical) => match len {
-                        2.. => rows_reverse(&mut layouts),
-                        _ => {}
-                    },
-                    _ => {}
+                if matches!(
+                    layout_flip,
+                    Some(Axis::Vertical | Axis::HorizontalAndVertical)
+                ) {
+                    if let 2.. = len {
+                        rows_reverse(&mut layouts);
+                    }
                 }
 
                 layouts
@@ -135,28 +137,28 @@ impl Arrangement for DefaultLayout {
                         layout.right += adjustment.right;
                     });
 
-                match layout_flip {
-                    Some(Axis::Horizontal | Axis::HorizontalAndVertical) => match len {
-                        2.. => {
-                            let (primary, rest) = layouts.split_at_mut(1);
-                            let primary = &mut primary[0];
+                if matches!(
+                    layout_flip,
+                    Some(Axis::Horizontal | Axis::HorizontalAndVertical)
+                ) {
+                    if let 2.. = len {
+                        let (primary, rest) = layouts.split_at_mut(1);
+                        let primary = &mut primary[0];
 
-                            for rect in rest.iter_mut() {
-                                rect.left = primary.left;
-                            }
-                            primary.left = rest[0].left + rest[0].right;
+                        for rect in rest.iter_mut() {
+                            rect.left = primary.left;
                         }
-                        _ => {}
-                    },
-                    _ => {}
+                        primary.left = rest[0].left + rest[0].right;
+                    }
                 }
 
-                match layout_flip {
-                    Some(Axis::Vertical | Axis::HorizontalAndVertical) => match len {
-                        3.. => rows_reverse(&mut layouts[1..]),
-                        _ => {}
-                    },
-                    _ => {}
+                if matches!(
+                    layout_flip,
+                    Some(Axis::Vertical | Axis::HorizontalAndVertical)
+                ) {
+                    if let 3.. = len {
+                        rows_reverse(&mut layouts[1..]);
+                    }
                 }
 
                 layouts
@@ -207,28 +209,28 @@ impl Arrangement for DefaultLayout {
                         layout.right += adjustment.right;
                     });
 
-                match layout_flip {
-                    Some(Axis::Horizontal | Axis::HorizontalAndVertical) => match len {
-                        2.. => {
-                            let (primary, rest) = layouts.split_at_mut(1);
-                            let primary = &mut primary[0];
+                if matches!(
+                    layout_flip,
+                    Some(Axis::Horizontal | Axis::HorizontalAndVertical)
+                ) {
+                    if let 2.. = len {
+                        let (primary, rest) = layouts.split_at_mut(1);
+                        let primary = &mut primary[0];
 
-                            primary.left = rest[0].left;
-                            for rect in rest.iter_mut() {
-                                rect.left = primary.left + primary.right;
-                            }
+                        primary.left = rest[0].left;
+                        for rect in rest.iter_mut() {
+                            rect.left = primary.left + primary.right;
                         }
-                        _ => {}
-                    },
-                    _ => {}
+                    }
                 }
 
-                match layout_flip {
-                    Some(Axis::Vertical | Axis::HorizontalAndVertical) => match len {
-                        3.. => rows_reverse(&mut layouts[1..]),
-                        _ => {}
-                    },
-                    _ => {}
+                if matches!(
+                    layout_flip,
+                    Some(Axis::Vertical | Axis::HorizontalAndVertical)
+                ) {
+                    if let 3.. = len {
+                        rows_reverse(&mut layouts[1..]);
+                    }
                 }
 
                 layouts
@@ -276,28 +278,28 @@ impl Arrangement for DefaultLayout {
                         layout.right += adjustment.right;
                     });
 
-                match layout_flip {
-                    Some(Axis::Vertical | Axis::HorizontalAndVertical) => match len {
-                        2.. => {
-                            let (primary, rest) = layouts.split_at_mut(1);
-                            let primary = &mut primary[0];
+                if matches!(
+                    layout_flip,
+                    Some(Axis::Vertical | Axis::HorizontalAndVertical)
+                ) {
+                    if let 2.. = len {
+                        let (primary, rest) = layouts.split_at_mut(1);
+                        let primary = &mut primary[0];
 
-                            for rect in rest.iter_mut() {
-                                rect.top = primary.top;
-                            }
-                            primary.top = rest[0].top + rest[0].bottom;
+                        for rect in rest.iter_mut() {
+                            rect.top = primary.top;
                         }
-                        _ => {}
-                    },
-                    _ => {}
+                        primary.top = rest[0].top + rest[0].bottom;
+                    }
                 }
 
-                match layout_flip {
-                    Some(Axis::Horizontal | Axis::HorizontalAndVertical) => match len {
-                        3.. => columns_reverse(&mut layouts[1..]),
-                        _ => {}
-                    },
-                    _ => {}
+                if matches!(
+                    layout_flip,
+                    Some(Axis::Horizontal | Axis::HorizontalAndVertical)
+                ) {
+                    if let 3.. = len {
+                        columns_reverse(&mut layouts[1..]);
+                    }
                 }
 
                 layouts
@@ -374,8 +376,11 @@ impl Arrangement for DefaultLayout {
                         layout.right += adjustment.right;
                     });
 
-                match layout_flip {
-                    Some(Axis::Horizontal | Axis::HorizontalAndVertical) => match len {
+                if matches!(
+                    layout_flip,
+                    Some(Axis::Horizontal | Axis::HorizontalAndVertical)
+                ) {
+                    match len {
                         2 => {
                             let (primary, secondary) = layouts.split_at_mut(1);
                             let primary = &mut primary[0];
@@ -397,20 +402,20 @@ impl Arrangement for DefaultLayout {
                             secondary.left = primary.left + primary.right;
                         }
                         _ => {}
-                    },
-                    _ => {}
+                    }
                 }
 
-                match layout_flip {
-                    Some(Axis::Vertical | Axis::HorizontalAndVertical) => match len {
-                        4.. => rows_reverse(&mut layouts[2..]),
-                        _ => {}
-                    },
-                    _ => {}
+                if matches!(
+                    layout_flip,
+                    Some(Axis::Vertical | Axis::HorizontalAndVertical)
+                ) {
+                    if let 4.. = len {
+                        rows_reverse(&mut layouts[2..]);
+                    }
                 }
 
                 layouts
-            },
+            }
             #[allow(
                 clippy::cast_precision_loss,
                 clippy::cast_possible_truncation,

komorebi-core/src/lib.rs

@@ -283,6 +283,8 @@ pub enum MoveBehaviour {
     Swap,
     /// Insert the window container into the focused workspace on the adjacent monitor
     Insert,
+    /// Do nothing if trying to move a window container in the direction of an adjacent monitor
+    NoOp,
 }
 
 #[derive(

komorebi/src/border_manager/border.rs

@@ -19,6 +19,7 @@ use std::sync::atomic::Ordering;
 use std::sync::mpsc;
 use std::time::Duration;
 use windows::core::PCWSTR;
+use windows::Win32::Foundation::BOOL;
 use windows::Win32::Foundation::COLORREF;
 use windows::Win32::Foundation::HWND;
 use windows::Win32::Foundation::LPARAM;
@@ -47,10 +48,29 @@ use windows::Win32::UI::WindowsAndMessaging::WM_DESTROY;
 use windows::Win32::UI::WindowsAndMessaging::WM_PAINT;
 use windows::Win32::UI::WindowsAndMessaging::WNDCLASSW;
 
+pub extern "system" fn border_hwnds(hwnd: HWND, lparam: LPARAM) -> BOOL {
+    let hwnds = unsafe { &mut *(lparam.0 as *mut Vec<isize>) };
+
+    if let Ok(class) = WindowsApi::real_window_class_w(hwnd) {
+        if class.starts_with("komoborder") {
+            hwnds.push(hwnd.0);
+        }
+    }
+
+    true.into()
+}
+
+#[derive(Debug)]
 pub struct Border {
     pub hwnd: isize,
 }
 
+impl From<isize> for Border {
+    fn from(value: isize) -> Self {
+        Self { hwnd: value }
+    }
+}
+
 impl Border {
     pub const fn hwnd(&self) -> HWND {
         HWND(self.hwnd)
@@ -97,7 +117,7 @@ impl Border {
     }
 
     pub fn destroy(&self) -> color_eyre::Result<()> {
-        WindowsApi::destroy_window(self.hwnd())
+        WindowsApi::close_window(self.hwnd())
     }
 
     pub fn update(&self, rect: &Rect) -> color_eyre::Result<()> {

komorebi/src/border_manager/mod.rs

@@ -1,3 +1,5 @@
+#![deny(clippy::unwrap_used, clippy::expect_used)]
+
 mod border;
 
 use crossbeam_channel::Receiver;
@@ -9,19 +11,24 @@ use parking_lot::Mutex;
 use schemars::JsonSchema;
 use serde::Deserialize;
 use serde::Serialize;
+use std::collections::hash_map::Entry;
 use std::collections::HashMap;
 use std::sync::atomic::AtomicBool;
 use std::sync::atomic::AtomicI32;
 use std::sync::atomic::AtomicU32;
 use std::sync::Arc;
 use std::sync::OnceLock;
+use std::time::Duration;
+use std::time::Instant;
 use windows::Win32::Foundation::HWND;
 
+use crate::workspace_reconciliator::ALT_TAB_HWND;
 use crate::Colour;
 use crate::Rect;
 use crate::Rgb;
 use crate::WindowManager;
 use crate::WindowsApi;
+use border::border_hwnds;
 use border::Border;
 use komorebi_core::WindowKind;
 
@@ -66,125 +73,103 @@ pub fn event_rx() -> Receiver<Notification> {
     channel().1.clone()
 }
 
+pub fn destroy_all_borders() -> color_eyre::Result<()> {
+    let mut borders = BORDER_STATE.lock();
+    tracing::info!(
+        "purging known borders: {:?}",
+        borders.iter().map(|b| b.1.hwnd).collect::<Vec<_>>()
+    );
+
+    for (_, border) in borders.iter() {
+        border.destroy()?;
+    }
+
+    borders.clear();
+    RECT_STATE.lock().clear();
+    BORDERS_MONITORS.lock().clear();
+    FOCUS_STATE.lock().clear();
+
+    let mut remaining_hwnds = vec![];
+
+    WindowsApi::enum_windows(
+        Some(border_hwnds),
+        &mut remaining_hwnds as *mut Vec<isize> as isize,
+    )?;
+
+    if !remaining_hwnds.is_empty() {
+        tracing::info!("purging unknown borders: {:?}", remaining_hwnds);
+
+        for hwnd in remaining_hwnds {
+            Border::from(hwnd).destroy()?;
+        }
+    }
+
+    Ok(())
+}
+
 pub fn listen_for_notifications(wm: Arc<Mutex<WindowManager>>) {
+    std::thread::spawn(move || loop {
+        match handle_notifications(wm.clone()) {
+            Ok(()) => {
+                tracing::warn!("restarting finished thread");
+            }
+            Err(error) => {
+                tracing::warn!("restarting failed thread: {}", error);
+            }
+        }
+    });
+}
+
+pub fn handle_notifications(wm: Arc<Mutex<WindowManager>>) -> color_eyre::Result<()> {
     tracing::info!("listening");
+
     let receiver = event_rx();
+    let mut instant: Option<Instant> = None;
+    event_tx().send(Notification)?;
 
-    std::thread::spawn(move || -> color_eyre::Result<()> {
-        'receiver: for _ in receiver {
-            let mut borders = BORDER_STATE.lock();
-            let mut borders_monitors = BORDERS_MONITORS.lock();
-
-            // Check the wm state every time we receive a notification
-            let state = wm.lock();
-
-            if !BORDER_ENABLED.load_consume() || state.is_paused {
-                if !borders.is_empty() {
-                    for (_, border) in borders.iter() {
-                        border.destroy()?;
-                    }
-
-                    borders.clear();
-                }
-
+    'receiver: for _ in receiver {
+        if let Some(instant) = instant {
+            if instant.elapsed().lt(&Duration::from_millis(50)) {
                 continue 'receiver;
             }
+        }
 
-            let focused_monitor_idx = state.focused_monitor_idx();
+        instant = Some(Instant::now());
 
-            for (monitor_idx, m) in state.monitors.elements().iter().enumerate() {
-                // Only operate on the focused workspace of each monitor
-                if let Some(ws) = m.focused_workspace() {
-                    // Workspaces with tiling disabled don't have borders
-                    if !ws.tile() {
-                        let mut to_remove = vec![];
-                        for (id, border) in borders.iter() {
-                            if borders_monitors.get(id).copied().unwrap_or_default() == monitor_idx
-                            {
-                                border.destroy()?;
-                                to_remove.push(id.clone());
-                            }
-                        }
+        let mut borders = BORDER_STATE.lock();
+        let mut borders_monitors = BORDERS_MONITORS.lock();
 
-                        for id in &to_remove {
-                            borders.remove(id);
-                        }
+        // Check the wm state every time we receive a notification
+        let state = wm.lock();
 
-                        continue 'receiver;
-                    }
+        // If borders are disabled
+        if !BORDER_ENABLED.load_consume()
+           // Or if the wm is paused
+            || state.is_paused
+            // Or if we are handling an alt-tab across workspaces
+            || ALT_TAB_HWND.load().is_some()
+        {
+            // Destroy the borders we know about
+            for (_, border) in borders.iter() {
+                border.destroy()?;
+            }
 
-                    // Handle the monocle container separately
-                    if let Some(monocle) = ws.monocle_container() {
-                        let mut to_remove = vec![];
-                        for (id, border) in borders.iter() {
-                            if borders_monitors.get(id).copied().unwrap_or_default() == monitor_idx
-                            {
-                                border.destroy()?;
-                                to_remove.push(id.clone());
-                            }
-                        }
+            borders.clear();
+            continue 'receiver;
+        }
 
-                        for id in &to_remove {
-                            borders.remove(id);
-                        }
-
-                        let border = borders.entry(monocle.id().clone()).or_insert_with(|| {
-                            Border::create(monocle.id()).expect("border creation failed")
-                        });
-
-                        borders_monitors.insert(monocle.id().clone(), monitor_idx);
-
-                        {
-                            let mut focus_state = FOCUS_STATE.lock();
-                            focus_state.insert(border.hwnd, WindowKind::Monocle);
-                        }
-
-                        let rect = WindowsApi::window_rect(
-                            monocle
-                                .focused_window()
-                                .expect("monocle container has no focused window")
-                                .hwnd(),
-                        )?;
-
-                        border.update(&rect)?;
-                        continue 'receiver;
-                    }
-
-                    let is_maximized = WindowsApi::is_zoomed(HWND(
-                        WindowsApi::foreground_window().unwrap_or_default(),
-                    ));
-
-                    if is_maximized {
-                        let mut to_remove = vec![];
-                        for (id, border) in borders.iter() {
-                            if borders_monitors.get(id).copied().unwrap_or_default() == monitor_idx
-                            {
-                                border.destroy()?;
-                                to_remove.push(id.clone());
-                            }
-                        }
-
-                        for id in &to_remove {
-                            borders.remove(id);
-                        }
-
-                        continue 'receiver;
-                    }
-
-                    // Destroy any borders not associated with the focused workspace
-                    let container_ids = ws
-                        .containers()
-                        .iter()
-                        .map(|c| c.id().clone())
-                        .collect::<Vec<_>>();
+        let focused_monitor_idx = state.focused_monitor_idx();
 
+        for (monitor_idx, m) in state.monitors.elements().iter().enumerate() {
+            // Only operate on the focused workspace of each monitor
+            if let Some(ws) = m.focused_workspace() {
+                // Workspaces with tiling disabled don't have borders
+                if !ws.tile() {
                     let mut to_remove = vec![];
                     for (id, border) in borders.iter() {
                         if borders_monitors.get(id).copied().unwrap_or_default() == monitor_idx {
-                            if !container_ids.contains(id) {
-                                border.destroy()?;
-                                to_remove.push(id.clone());
-                            }
+                            border.destroy()?;
+                            to_remove.push(id.clone());
                         }
                     }
 
@@ -192,80 +177,169 @@ pub fn listen_for_notifications(wm: Arc<Mutex<WindowManager>>) {
                         borders.remove(id);
                     }
 
-                    for (idx, c) in ws.containers().iter().enumerate() {
-                        // Update border when moving or resizing with mouse
-                        if state.pending_move_op.is_some() && idx == ws.focused_container_idx() {
-                            let restore_z_order = *Z_ORDER.lock();
-                            *Z_ORDER.lock() = ZOrder::TopMost;
+                    continue 'receiver;
+                }
 
-                            let mut rect = WindowsApi::window_rect(
-                                c.focused_window()
-                                    .expect("container has no focused window")
-                                    .hwnd(),
-                            )?;
+                // Handle the monocle container separately
+                if let Some(monocle) = ws.monocle_container() {
+                    let mut to_remove = vec![];
+                    for (id, border) in borders.iter() {
+                        if borders_monitors.get(id).copied().unwrap_or_default() == monitor_idx {
+                            border.destroy()?;
+                            to_remove.push(id.clone());
+                        }
+                    }
 
-                            while WindowsApi::lbutton_is_pressed() {
-                                let border = borders.entry(c.id().clone()).or_insert_with(|| {
-                                    Border::create(c.id()).expect("border creation failed")
-                                });
+                    for id in &to_remove {
+                        borders.remove(id);
+                    }
 
-                                let new_rect = WindowsApi::window_rect(
-                                    c.focused_window()
-                                        .expect("container has no focused window")
-                                        .hwnd(),
-                                )?;
-
-                                if rect != new_rect {
-                                    rect = new_rect;
-                                    border.update(&rect)?;
-                                }
+                    let border = match borders.entry(monocle.id().clone()) {
+                        Entry::Occupied(entry) => entry.into_mut(),
+                        Entry::Vacant(entry) => {
+                            if let Ok(border) = Border::create(monocle.id()) {
+                                entry.insert(border)
+                            } else {
+                                continue 'receiver;
                             }
-
-                            *Z_ORDER.lock() = restore_z_order;
-
-                            continue 'receiver;
                         }
+                    };
 
-                        // Get the border entry for this container from the map or create one
-                        let border = borders.entry(c.id().clone()).or_insert_with(|| {
-                            Border::create(c.id()).expect("border creation failed")
-                        });
+                    borders_monitors.insert(monocle.id().clone(), monitor_idx);
 
-                        borders_monitors.insert(c.id().clone(), monitor_idx);
+                    {
+                        let mut focus_state = FOCUS_STATE.lock();
+                        focus_state.insert(border.hwnd, WindowKind::Monocle);
+                    }
 
-                        // Update the focused state for all containers on this workspace
-                        {
-                            let mut focus_state = FOCUS_STATE.lock();
-                            focus_state.insert(
-                                border.hwnd,
-                                if idx != ws.focused_container_idx()
-                                    || monitor_idx != focused_monitor_idx
-                                {
-                                    WindowKind::Unfocused
-                                } else {
-                                    if c.windows().len() > 1 {
-                                        WindowKind::Stack
-                                    } else {
-                                        WindowKind::Single
-                                    }
-                                },
-                            );
+                    let rect = WindowsApi::window_rect(
+                        monocle.focused_window().copied().unwrap_or_default().hwnd(),
+                    )?;
+
+                    border.update(&rect)?;
+                    continue 'receiver;
+                }
+
+                let is_maximized = WindowsApi::is_zoomed(HWND(
+                    WindowsApi::foreground_window().unwrap_or_default(),
+                ));
+
+                if is_maximized {
+                    let mut to_remove = vec![];
+                    for (id, border) in borders.iter() {
+                        if borders_monitors.get(id).copied().unwrap_or_default() == monitor_idx {
+                            border.destroy()?;
+                            to_remove.push(id.clone());
                         }
+                    }
 
-                        let rect = WindowsApi::window_rect(
-                            c.focused_window()
-                                .expect("container has no focused window")
-                                .hwnd(),
+                    for id in &to_remove {
+                        borders.remove(id);
+                    }
+
+                    continue 'receiver;
+                }
+
+                // Destroy any borders not associated with the focused workspace
+                let container_ids = ws
+                    .containers()
+                    .iter()
+                    .map(|c| c.id().clone())
+                    .collect::<Vec<_>>();
+
+                let mut to_remove = vec![];
+                for (id, border) in borders.iter() {
+                    if borders_monitors.get(id).copied().unwrap_or_default() == monitor_idx
+                        && !container_ids.contains(id)
+                    {
+                        border.destroy()?;
+                        to_remove.push(id.clone());
+                    }
+                }
+
+                for id in &to_remove {
+                    borders.remove(id);
+                }
+
+                for (idx, c) in ws.containers().iter().enumerate() {
+                    // Update border when moving or resizing with mouse
+                    if state.pending_move_op.is_some() && idx == ws.focused_container_idx() {
+                        let restore_z_order = *Z_ORDER.lock();
+                        *Z_ORDER.lock() = ZOrder::TopMost;
+
+                        let mut rect = WindowsApi::window_rect(
+                            c.focused_window().copied().unwrap_or_default().hwnd(),
                         )?;
 
-                        border.update(&rect)?;
+                        while WindowsApi::lbutton_is_pressed() {
+                            let border = match borders.entry(c.id().clone()) {
+                                Entry::Occupied(entry) => entry.into_mut(),
+                                Entry::Vacant(entry) => {
+                                    if let Ok(border) = Border::create(c.id()) {
+                                        entry.insert(border)
+                                    } else {
+                                        continue 'receiver;
+                                    }
+                                }
+                            };
+
+                            let new_rect = WindowsApi::window_rect(
+                                c.focused_window().copied().unwrap_or_default().hwnd(),
+                            )?;
+
+                            if rect != new_rect {
+                                rect = new_rect;
+                                border.update(&rect)?;
+                            }
+                        }
+
+                        *Z_ORDER.lock() = restore_z_order;
+
+                        continue 'receiver;
                     }
+
+                    // Get the border entry for this container from the map or create one
+                    let border = match borders.entry(c.id().clone()) {
+                        Entry::Occupied(entry) => entry.into_mut(),
+                        Entry::Vacant(entry) => {
+                            if let Ok(border) = Border::create(c.id()) {
+                                entry.insert(border)
+                            } else {
+                                continue 'receiver;
+                            }
+                        }
+                    };
+
+                    borders_monitors.insert(c.id().clone(), monitor_idx);
+
+                    // Update the focused state for all containers on this workspace
+                    {
+                        let mut focus_state = FOCUS_STATE.lock();
+                        focus_state.insert(
+                            border.hwnd,
+                            if idx != ws.focused_container_idx()
+                                || monitor_idx != focused_monitor_idx
+                            {
+                                WindowKind::Unfocused
+                            } else if c.windows().len() > 1 {
+                                WindowKind::Stack
+                            } else {
+                                WindowKind::Single
+                            },
+                        );
+                    }
+
+                    let rect = WindowsApi::window_rect(
+                        c.focused_window().copied().unwrap_or_default().hwnd(),
+                    )?;
+
+                    border.update(&rect)?;
                 }
             }
         }
+    }
 
-        Ok(())
-    });
+    Ok(())
 }
 
 #[derive(Debug, Copy, Clone, Serialize, Deserialize, JsonSchema)]
@@ -276,9 +350,9 @@ pub enum ZOrder {
     TopMost,
 }
 
-impl Into<isize> for ZOrder {
-    fn into(self) -> isize {
-        match self {
+impl From<ZOrder> for isize {
+    fn from(val: ZOrder) -> Self {
+        match val {
             ZOrder::Top => 0,
             ZOrder::NoTopMost => -2,
             ZOrder::Bottom => 1,

komorebi/src/lib.rs

@@ -21,6 +21,7 @@ pub mod windows_callbacks;
 pub mod winevent;
 pub mod winevent_listener;
 pub mod workspace;
+pub mod workspace_reconciliator;
 
 use lazy_static::lazy_static;
 use std::collections::HashMap;

komorebi/src/main.rs

@@ -34,6 +34,7 @@ use komorebi::static_config::StaticConfig;
 use komorebi::window_manager::WindowManager;
 use komorebi::windows_api::WindowsApi;
 use komorebi::winevent_listener;
+use komorebi::workspace_reconciliator;
 use komorebi::CUSTOM_FFM;
 use komorebi::DATA_DIR;
 use komorebi::HOME_DIR;
@@ -255,6 +256,7 @@ fn main() -> Result<()> {
     }
 
     border_manager::listen_for_notifications(wm.clone());
+    workspace_reconciliator::listen_for_notifications(wm.clone());
 
     let (ctrlc_sender, ctrlc_receiver) = crossbeam_channel::bounded(1);
     ctrlc::set_handler(move || {

komorebi/src/process_command.rs

@@ -492,7 +492,10 @@ impl WindowManager {
                 self.focus_monitor(monitor_idx)?;
                 self.update_focused_workspace(self.mouse_follows_focus, true)?;
             }
-            SocketMessage::Retile => self.retile_all(false)?,
+            SocketMessage::Retile => {
+                border_manager::destroy_all_borders()?;
+                self.retile_all(false)?
+            }
             SocketMessage::FlipLayout(layout_flip) => self.flip_layout(layout_flip)?,
             SocketMessage::ChangeLayout(layout) => self.change_workspace_layout_default(layout)?,
             SocketMessage::CycleLayout(direction) => self.cycle_layout(direction)?,
@@ -647,7 +650,9 @@ impl WindowManager {
                     self.focus_monitor(monitor_idx)?;
                 }
 
-                self.focus_workspace(workspace_idx)?;
+                if self.focused_workspace_idx().unwrap_or_default() != workspace_idx {
+                    self.focus_workspace(workspace_idx)?;
+                }
             }
             SocketMessage::FocusWorkspaceNumbers(workspace_idx) => {
                 // This is to ensure that even on an empty workspace on a secondary monitor, the
@@ -669,8 +674,15 @@ impl WindowManager {
                 self.focus_workspace(workspace_idx)?;
             }
             SocketMessage::FocusMonitorWorkspaceNumber(monitor_idx, workspace_idx) => {
-                self.focus_monitor(monitor_idx)?;
-                self.focus_workspace(workspace_idx)?;
+                let focused_monitor_idx = self.focused_monitor_idx();
+                let focused_workspace_idx = self.focused_workspace_idx().unwrap_or_default();
+
+                let focused_pair = (focused_monitor_idx, focused_workspace_idx);
+
+                if focused_pair != (monitor_idx, workspace_idx) {
+                    self.focus_monitor(monitor_idx)?;
+                    self.focus_workspace(workspace_idx)?;
+                }
             }
             SocketMessage::FocusNamedWorkspace(ref name) => {
                 if let Some((monitor_idx, workspace_idx)) =
@@ -1184,6 +1196,7 @@ impl WindowManager {
                     MoveBehaviour::Insert => {
                         self.cross_monitor_move_behaviour = MoveBehaviour::Swap;
                     }
+                    _ => {}
                 }
             }
             SocketMessage::CrossMonitorMoveBehaviour(behaviour) => {

komorebi/src/process_event.rs

@@ -1,6 +1,8 @@
 use std::fs::OpenOptions;
 use std::sync::atomic::Ordering;
 use std::sync::Arc;
+use std::time::Duration;
+use std::time::Instant;
 
 use color_eyre::eyre::anyhow;
 use color_eyre::Result;
@@ -22,6 +24,9 @@ use crate::window_manager::WindowManager;
 use crate::window_manager_event::WindowManagerEvent;
 use crate::windows_api::WindowsApi;
 use crate::winevent::WinEvent;
+use crate::workspace_reconciliator;
+use crate::workspace_reconciliator::ALT_TAB_HWND;
+use crate::workspace_reconciliator::ALT_TAB_HWND_INSTANT;
 use crate::Notification;
 use crate::NotificationEvent;
 use crate::DATA_DIR;
@@ -259,74 +264,86 @@ impl WindowManager {
             WindowManagerEvent::Show(_, window)
             | WindowManagerEvent::Manage(window)
             | WindowManagerEvent::Uncloak(_, window) => {
-                let mut switch_to = None;
+                let focused_monitor_idx = self.focused_monitor_idx();
+                let focused_workspace_idx =
+                    self.focused_workspace_idx_for_monitor_idx(focused_monitor_idx)?;
+
+                let focused_pair = (focused_monitor_idx, focused_workspace_idx);
+
+                let mut needs_reconciliation = false;
+
                 for (i, monitors) in self.monitors().iter().enumerate() {
                     for (j, workspace) in monitors.workspaces().iter().enumerate() {
-                        if workspace.contains_window(window.hwnd) {
-                            switch_to = Some((i, j));
+                        if workspace.contains_window(window.hwnd) && focused_pair != (i, j) {
+                            // At this point we know we are going to send a notification to the workspace reconciliator
+                            // So we get the topmost window returned by EnumWindows, which is almost always the window
+                            // that has been selected by alt-tab
+                            if let Ok(alt_tab_windows) = WindowsApi::alt_tab_windows() {
+                                if let Some(first) =
+                                    alt_tab_windows.iter().find(|w| w.title().is_ok())
+                                {
+                                    // If our record of this HWND hasn't been updated in over a minute
+                                    let mut instant = ALT_TAB_HWND_INSTANT.lock();
+                                    if instant.elapsed().gt(&Duration::from_secs(1)) {
+                                        // Update our record with the HWND we just found
+                                        ALT_TAB_HWND.store(Some(first.hwnd));
+                                        // Update the timestamp of our record
+                                        *instant = Instant::now();
+                                    }
+                                }
+                            }
+
+                            workspace_reconciliator::event_tx().send(
+                                workspace_reconciliator::Notification {
+                                    monitor_idx: i,
+                                    workspace_idx: j,
+                                },
+                            )?;
+
+                            needs_reconciliation = true;
                         }
                     }
                 }
 
-                match switch_to {
-                    Some((known_monitor_idx, known_workspace_idx)) => {
-                        if !matches!(event, WindowManagerEvent::Uncloak(_, _)) {
-                            if self.focused_monitor_idx() != known_monitor_idx
-                                || self
-                                    .focused_monitor()
-                                    .ok_or_else(|| anyhow!("there is no monitor"))?
-                                    .focused_workspace_idx()
-                                    != known_workspace_idx
-                            {
-                                self.focus_monitor(known_monitor_idx)?;
-                                self.focus_workspace(known_workspace_idx)?;
-                            }
-                        }
-                    }
-                    None => {
-                        // There are some applications such as Firefox where, if they are focused when a
-                        // workspace switch takes place, it will fire an additional Show event, which will
-                        // result in them being associated with both the original workspace and the workspace
-                        // being switched to. This loop is to try to ensure that we don't end up with
-                        // duplicates across multiple workspaces, as it results in ghost layout tiles.
-                        let mut proceed = true;
+                // There are some applications such as Firefox where, if they are focused when a
+                // workspace switch takes place, it will fire an additional Show event, which will
+                // result in them being associated with both the original workspace and the workspace
+                // being switched to. This loop is to try to ensure that we don't end up with
+                // duplicates across multiple workspaces, as it results in ghost layout tiles.
+                let mut proceed = true;
 
-                        for (i, monitor) in self.monitors().iter().enumerate() {
-                            for (j, workspace) in monitor.workspaces().iter().enumerate() {
-                                if workspace.container_for_window(window.hwnd).is_some()
-                                    && i != self.focused_monitor_idx()
-                                    && j != monitor.focused_workspace_idx()
-                                {
-                                    tracing::debug!(
+                for (i, monitor) in self.monitors().iter().enumerate() {
+                    for (j, workspace) in monitor.workspaces().iter().enumerate() {
+                        if workspace.container_for_window(window.hwnd).is_some()
+                            && i != self.focused_monitor_idx()
+                            && j != monitor.focused_workspace_idx()
+                        {
+                            tracing::debug!(
                                 "ignoring show event for window already associated with another workspace"
                             );
 
-                                    window.hide();
-                                    proceed = false;
-                                }
-                            }
+                            window.hide();
+                            proceed = false;
                         }
+                    }
+                }
 
-                        if proceed {
-                            let behaviour = self.window_container_behaviour;
-                            let workspace = self.focused_workspace_mut()?;
+                if proceed {
+                    let behaviour = self.window_container_behaviour;
+                    let workspace = self.focused_workspace_mut()?;
 
-                            if !workspace.contains_window(window.hwnd) && switch_to.is_none() {
-                                match behaviour {
-                                    WindowContainerBehaviour::Create => {
-                                        workspace.new_container_for_window(window);
-                                        self.update_focused_workspace(false, false)?;
-                                    }
-                                    WindowContainerBehaviour::Append => {
-                                        workspace
-                                            .focused_container_mut()
-                                            .ok_or_else(|| {
-                                                anyhow!("there is no focused container")
-                                            })?
-                                            .add_window(window);
-                                        self.update_focused_workspace(true, false)?;
-                                    }
-                                }
+                    if !workspace.contains_window(window.hwnd) && !needs_reconciliation {
+                        match behaviour {
+                            WindowContainerBehaviour::Create => {
+                                workspace.new_container_for_window(window);
+                                self.update_focused_workspace(false, false)?;
+                            }
+                            WindowContainerBehaviour::Append => {
+                                workspace
+                                    .focused_container_mut()
+                                    .ok_or_else(|| anyhow!("there is no focused container"))?
+                                    .add_window(window);
+                                self.update_focused_workspace(true, false)?;
                             }
                         }
                     }

komorebi/src/window.rs

@@ -38,7 +38,7 @@ use crate::PERMAIGNORE_CLASSES;
 use crate::REGEX_IDENTIFIERS;
 use crate::WSL2_UI_PROCESSES;
 
-#[derive(Debug, Clone, Copy, Deserialize, JsonSchema)]
+#[derive(Debug, Default, Clone, Copy, Deserialize, JsonSchema)]
 pub struct Window {
     pub hwnd: isize,
 }

komorebi/src/window_manager.rs

@@ -1273,6 +1273,11 @@ impl WindowManager {
 
         let workspace = self.focused_workspace()?;
 
+        // Do not proceed if we have a monocle container or maximized window
+        if workspace.monocle_container().is_some() || workspace.maximized_window().is_some() {
+            return Ok(());
+        }
+
         tracing::info!("focusing container");
 
         let new_idx = workspace.new_idx_for_direction(direction);
@@ -1333,6 +1338,11 @@ impl WindowManager {
             // If there is nowhere to move on the current workspace, try to move it onto the monitor
             // in that direction if there is one
             None => {
+                // Don't do anything if the user has set the MoveBehaviour to NoOp
+                if matches!(self.cross_monitor_move_behaviour, MoveBehaviour::NoOp) {
+                    return Ok(());
+                }
+
                 let target_monitor_idx = self
                     .monitor_idx_in_direction(direction)
                     .ok_or_else(|| anyhow!("there is no container or monitor in this direction"))?;
@@ -2307,6 +2317,13 @@ impl WindowManager {
         None
     }
 
+    pub fn focused_workspace_idx(&self) -> Result<usize> {
+        Ok(self
+            .focused_monitor()
+            .ok_or_else(|| anyhow!("there is no monitor"))?
+            .focused_workspace_idx())
+    }
+
     pub fn focused_workspace(&self) -> Result<&Workspace> {
         self.focused_monitor()
             .ok_or_else(|| anyhow!("there is no monitor"))?

komorebi/src/windows_api.rs

@@ -121,7 +121,6 @@ use windows::Win32::UI::WindowsAndMessaging::SYSTEM_PARAMETERS_INFO_ACTION;
 use windows::Win32::UI::WindowsAndMessaging::SYSTEM_PARAMETERS_INFO_UPDATE_FLAGS;
 use windows::Win32::UI::WindowsAndMessaging::WINDOW_LONG_PTR_INDEX;
 use windows::Win32::UI::WindowsAndMessaging::WM_CLOSE;
-use windows::Win32::UI::WindowsAndMessaging::WM_DESTROY;
 use windows::Win32::UI::WindowsAndMessaging::WNDCLASSW;
 use windows::Win32::UI::WindowsAndMessaging::WNDENUMPROC;
 use windows::Win32::UI::WindowsAndMessaging::WS_DISABLED;
@@ -140,6 +139,7 @@ use crate::monitor::Monitor;
 use crate::ring::Ring;
 use crate::set_window_position::SetWindowPosition;
 use crate::windows_callbacks;
+use crate::Window;
 
 pub enum WindowsResult<T, E> {
     Err(E),
@@ -433,13 +433,6 @@ impl WindowsApi {
         }
     }
 
-    pub fn destroy_window(hwnd: HWND) -> Result<()> {
-        match Self::post_message(hwnd, WM_DESTROY, WPARAM(0), LPARAM(0)) {
-            Ok(()) => Ok(()),
-            Err(_) => Err(anyhow!("could not close window")),
-        }
-    }
-
     pub fn hide_window(hwnd: HWND) {
         Self::show_window(hwnd, SW_HIDE);
     }
@@ -501,6 +494,16 @@ impl WindowsApi {
         unsafe { GetWindow(hwnd, GW_HWNDNEXT) }.process()
     }
 
+    pub fn alt_tab_windows() -> Result<Vec<Window>> {
+        let mut hwnds = vec![];
+        Self::enum_windows(
+            Some(windows_callbacks::alt_tab_windows),
+            &mut hwnds as *mut Vec<Window> as isize,
+        )?;
+
+        Ok(hwnds)
+    }
+
     #[allow(dead_code)]
     pub fn top_visible_window() -> Result<isize> {
         let hwnd = Self::top_window()?;

komorebi/src/windows_callbacks.rs

@@ -152,6 +152,26 @@ pub extern "system" fn enum_window(hwnd: HWND, lparam: LPARAM) -> BOOL {
     true.into()
 }
 
+pub extern "system" fn alt_tab_windows(hwnd: HWND, lparam: LPARAM) -> BOOL {
+    let windows = unsafe { &mut *(lparam.0 as *mut Vec<Window>) };
+
+    let is_visible = WindowsApi::is_window_visible(hwnd);
+    let is_window = WindowsApi::is_window(hwnd);
+    let is_minimized = WindowsApi::is_iconic(hwnd);
+
+    if is_visible && is_window && !is_minimized {
+        let window = Window { hwnd: hwnd.0 };
+
+        if let Ok(should_manage) = window.should_manage(None, &mut RuleDebug::default()) {
+            if should_manage {
+                windows.push(window);
+            }
+        }
+    }
+
+    true.into()
+}
+
 pub extern "system" fn win_event_hook(
     _h_win_event_hook: HWINEVENTHOOK,
     event: u32,

komorebi/src/workspace_reconciliator.rs

@@ -0,0 +1,116 @@
+#![deny(clippy::unwrap_used, clippy::expect_used)]
+
+use crate::border_manager;
+use crate::WindowManager;
+use crossbeam_channel::Receiver;
+use crossbeam_channel::Sender;
+use crossbeam_utils::atomic::AtomicCell;
+use lazy_static::lazy_static;
+use parking_lot::Mutex;
+use std::sync::Arc;
+use std::sync::OnceLock;
+use std::time::Duration;
+use std::time::Instant;
+
+#[derive(Copy, Clone)]
+pub struct Notification {
+    pub monitor_idx: usize,
+    pub workspace_idx: usize,
+}
+
+pub static ALT_TAB_HWND: AtomicCell<Option<isize>> = AtomicCell::new(None);
+
+lazy_static! {
+    pub static ref ALT_TAB_HWND_INSTANT: Arc<Mutex<Instant>> = Arc::new(Mutex::new(Instant::now()));
+}
+
+static CHANNEL: OnceLock<(Sender<Notification>, Receiver<Notification>)> = OnceLock::new();
+
+pub fn channel() -> &'static (Sender<Notification>, Receiver<Notification>) {
+    CHANNEL.get_or_init(|| crossbeam_channel::bounded(1))
+}
+
+pub fn event_tx() -> Sender<Notification> {
+    channel().0.clone()
+}
+
+pub fn event_rx() -> Receiver<Notification> {
+    channel().1.clone()
+}
+
+pub fn listen_for_notifications(wm: Arc<Mutex<WindowManager>>) {
+    std::thread::spawn(move || loop {
+        match handle_notifications(wm.clone()) {
+            Ok(()) => {
+                tracing::warn!("restarting finished thread");
+            }
+            Err(error) => {
+                if cfg!(debug_assertions) {
+                    tracing::error!("restarting failed thread: {:?}", error)
+                } else {
+                    tracing::error!("restarting failed thread: {}", error)
+                }
+            }
+        }
+    });
+}
+pub fn handle_notifications(wm: Arc<Mutex<WindowManager>>) -> color_eyre::Result<()> {
+    tracing::info!("listening");
+
+    let receiver = event_rx();
+    let arc = wm.clone();
+
+    for notification in receiver {
+        tracing::info!("running reconciliation");
+
+        let mut wm = wm.lock();
+        let focused_monitor_idx = wm.focused_monitor_idx();
+        let focused_workspace_idx =
+            wm.focused_workspace_idx_for_monitor_idx(focused_monitor_idx)?;
+
+        let focused_pair = (focused_monitor_idx, focused_workspace_idx);
+        let updated_pair = (notification.monitor_idx, notification.workspace_idx);
+
+        if focused_pair != updated_pair {
+            wm.focus_monitor(notification.monitor_idx)?;
+            let mouse_follows_focus = wm.mouse_follows_focus;
+
+            if let Some(monitor) = wm.focused_monitor_mut() {
+                monitor.focus_workspace(notification.workspace_idx)?;
+                monitor.load_focused_workspace(mouse_follows_focus)?;
+            }
+
+            // Drop our lock on the window manager state here to not slow down updates
+            drop(wm);
+
+            // Check if there was an alt-tab across workspaces in the last second
+            if let Some(hwnd) = ALT_TAB_HWND.load() {
+                if ALT_TAB_HWND_INSTANT
+                    .lock()
+                    .elapsed()
+                    .lt(&Duration::from_secs(1))
+                {
+                    // Sleep for 100 millis to let other events pass
+                    std::thread::sleep(Duration::from_millis(100));
+                    tracing::info!("focusing alt-tabbed window");
+
+                    // Take a new lock on the wm and try to focus the container with
+                    // the recorded HWND from the alt-tab
+                    let mut wm = arc.lock();
+                    if let Ok(workspace) = wm.focused_workspace_mut() {
+                        // Regardless of if this fails, we need to get past this part
+                        // to unblock the border manager below
+                        let _ = workspace.focus_container_by_window(hwnd);
+                    }
+
+                    // Unblock the border manager
+                    ALT_TAB_HWND.store(None);
+                    // Send a notification to the border manager to update the borders
+                    border_manager::event_tx().send(border_manager::Notification)?;
+                }
+            }
+        }
+    }
+
+    Ok(())
+}