feat(wm): allow focusing and moving by cycle direction

This commit adds focusing and moving window containers using cycle
directions when the layout has not been flipped on any axis.

This naive implementation simply increments or decrements the index
number in the desired direction and does not accomodate for axis
flipping.

When the current index number is either at the beginning or the end of
the collection, further operations will loop around.

Ideally I would like an implementation which works coherently on any
LayoutFlip state, but this can be implemented at a later date if
specifically requested in the future.

re #47

komorebi-core/src/cycle_direction.rs

@@ -1,6 +1,7 @@
 use clap::ArgEnum;
 use serde::Deserialize;
 use serde::Serialize;
+use std::num::NonZeroUsize;
 use strum::Display;
 use strum::EnumString;
 
@@ -13,17 +14,17 @@ pub enum CycleDirection {
 
 impl CycleDirection {
     #[must_use]
-    pub const fn next_idx(&self, idx: usize, len: usize) -> usize {
+    pub const fn next_idx(&self, idx: usize, len: NonZeroUsize) -> usize {
         match self {
-            CycleDirection::Previous => {
+            Self::Previous => {
                 if idx == 0 {
-                    len - 1
+                    len.get() - 1
                 } else {
                     idx - 1
                 }
             }
-            CycleDirection::Next => {
-                if idx == len - 1 {
+            Self::Next => {
+                if idx == len.get() - 1 {
                     0
                 } else {
                     idx + 1

komorebi-core/src/lib.rs

@@ -27,6 +27,8 @@ pub enum SocketMessage {
     // Window / Container Commands
     FocusWindow(OperationDirection),
     MoveWindow(OperationDirection),
+    CycleFocusWindow(CycleDirection),
+    CycleMoveWindow(CycleDirection),
     StackWindow(OperationDirection),
     ResizeWindow(OperationDirection, Sizing),
     UnstackWindow,

komorebi-core/src/operation_direction.rs

@@ -57,22 +57,22 @@ impl OperationDirection {
         len: usize,
     ) -> bool {
         match Self::flip_direction(self, layout_flip) {
-            OperationDirection::Up => match layout {
+            Self::Up => match layout {
                 Layout::BSP => len > 2 && idx != 0 && idx != 1,
                 Layout::Columns => false,
                 Layout::Rows => idx != 0,
             },
-            OperationDirection::Down => match layout {
+            Self::Down => match layout {
                 Layout::BSP => len > 2 && idx != len - 1 && idx % 2 != 0,
                 Layout::Columns => false,
                 Layout::Rows => idx != len - 1,
             },
-            OperationDirection::Left => match layout {
+            Self::Left => match layout {
                 Layout::BSP => len > 1 && idx != 0,
                 Layout::Columns => idx != 0,
                 Layout::Rows => false,
             },
-            OperationDirection::Right => match layout {
+            Self::Right => match layout {
                 Layout::BSP => len > 1 && idx % 2 == 0 && idx != len - 1,
                 Layout::Columns => idx != len - 1,
                 Layout::Rows => false,