Introduce a command to jump to a given window

The intended user of this command is a custom module of waybar, to
allow a on-click event.

We use this opportunity to prefer next/prev over left/right to use the
same type for workspaces-related commands.

6 files changed, 90 insertions, 33 deletions

diff --git a/README.md b/README.md
index c9c3a00..f09c9a5 100644
--- a/README.md
+++ b/README.md
@@ -23,16 +23,16 @@ exec $spatialmsg
 # focus is on the last window on the left of the visible area, windows
 # will shift right to make room for the next candidate on the loop,
 # and the window on the far right will disappear.
-bindsym $mod+t exec $spatialmsg "focus left"
+bindsym $mod+t exec $spatialmsg "focus prev"
 
 # Same thing, for the right.
-bindsym $mod+n exec $spatialmsg "focus right"
+bindsym $mod+n exec $spatialmsg "focus next"
 
 # Move the focused window on the left, shift the loop if necessary.
-bindsym $mod+Shift+t exec $spatialmsg "move left"
+bindsym $mod+Shift+t exec $spatialmsg "move prev"
 
 # Move the focused window on the right, shift the loop if necessary.
-bindsym $mod+Shift+n exec $spatialmsg "move right"
+bindsym $mod+Shift+n exec $spatialmsg "move next"
 
 # Toggle between a mode where only one window is visible (maximized
 # mode), or a fixed numbers (split mode). spatial-sway will remember
diff --git a/bin/spatial/ribbon.ml b/bin/spatial/ribbon.ml
index 24777ac..5af50c1 100644
--- a/bin/spatial/ribbon.ml
+++ b/bin/spatial/ribbon.ml
@@ -165,13 +165,25 @@ let move_focus_right ribbon =
           let x, l = pop_front_exn l in
           { ribbon with visible = Some (f, push_back x l) })
 
-let split_visible ribbon =
-  let rec split_visible acc f = function
-    | x :: rst when f = 0 -> Some (List.rev acc, x, rst)
-    | x :: rst -> split_visible (x :: acc) (f - 1) rst
-    | [] -> raise (Invalid_argument "Ribbon.split_visible")
+let rec focus_index ribbon index =
+  match ribbon.visible with
+  | Some (_, l) when index < List.length l ->
+      { ribbon with visible = Some (index, l) }
+  | Some (_, l) when index < List.length l + List.length ribbon.hidden ->
+      let ribbon = move_focus_right ribbon in
+      focus_index ribbon (index - 1)
+  | _ -> ribbon
+
+let split_at l i =
+  let rec split_visible acc i = function
+    | x :: rst when i = 0 -> Some (List.rev acc, x, rst)
+    | x :: rst -> split_visible (x :: acc) (i - 1) rst
+    | [] -> raise (Invalid_argument "Ribbon.split_at")
   in
-  match ribbon.visible with None -> None | Some (f, l) -> split_visible [] f l
+  split_visible [] i l
+
+let split_visible ribbon =
+  match ribbon.visible with None -> None | Some (f, l) -> split_at l f
 
 let move_window_left ribbon =
   match split_visible ribbon with
diff --git a/bin/spatial/state.ml b/bin/spatial/state.ml
index e978166..2b4f994 100644
--- a/bin/spatial/state.ml
+++ b/bin/spatial/state.ml
@@ -27,6 +27,16 @@ let insert_window default_full_view default_maximum_visible workspace window
       Windows_registry.register window { app_id; workspace } state.windows;
   }
 
+let focus_index workspace state index =
+  {
+    state with
+    workspaces =
+      Workspaces_registry.update workspace
+        (function
+          | Some ribbon -> Some (Ribbon.focus_index ribbon index) | None -> None)
+        state.workspaces;
+  }
+
 let toggle_full_view workspace state =
   {
     state with
@@ -138,7 +148,7 @@ let client_command_handle :
    | Run_command cmd ->
        let res =
          match cmd with
-         | Focus Left ->
+         | Focus Prev ->
              ( {
                  state with
                  workspaces =
@@ -150,7 +160,7 @@ let client_command_handle :
                },
                true,
                None )
-         | Focus Right ->
+         | Focus Next ->
              ( {
                  state with
                  workspaces =
@@ -162,9 +172,11 @@ let client_command_handle :
                },
                true,
                None )
-         | Move Left ->
+         | Focus (Index x) ->
+             (focus_index state.current_workspace state x, true, None)
+         | Move Prev ->
              (move_window_left state.current_workspace state, true, None)
-         | Move Right ->
+         | Move Next ->
              (move_window_right state.current_workspace state, true, None)
          | Maximize Toggle ->
              (toggle_full_view state.current_workspace state, true, None)
diff --git a/bin/spatialmsg/main.ml b/bin/spatialmsg/main.ml
index 9e7be1b..057b536 100644
--- a/bin/spatialmsg/main.ml
+++ b/bin/spatialmsg/main.ml
@@ -21,9 +21,17 @@ let () =
 
       match (cmd, reply.focus) with
       | Some idx, Some focus when idx < List.length reply.windows ->
-          let name = List.nth reply.windows idx in
+          let tooltip = List.nth reply.windows idx in
+          let name =
+            match tooltip with
+            | "firefox" -> ""
+            | "kitty" -> ""
+            | "Slack" -> ""
+            | "emacs" -> ""
+            | _ -> " " ^ tooltip
+          in
           let cls = if idx = focus then "focus" else "unfocus" in
-          Format.(printf "%s\n%s\n%s" name name cls)
+          Format.(printf "%s\n%s\n%s" name tooltip cls)
       | Some _, _ -> ()
       | None, _ ->
           List.iteri
diff --git a/lib/spatial_ipc/spatial_ipc.ml b/lib/spatial_ipc/spatial_ipc.ml
index 662582a..a574fc1 100644
--- a/lib/spatial_ipc/spatial_ipc.ml
+++ b/lib/spatial_ipc/spatial_ipc.ml
@@ -7,14 +7,30 @@ open Mltp_ipc
 let socket_path = "/tmp/spatial-sway.socket"
 let magic_string = "spatial-ipc"
 
-type direction = Left | Right
-
-let direction_of_string_opt = function
-  | "left" -> Some Left
-  | "right" -> Some Right
-  | _ -> None
-
-let direction_to_string = function Left -> "left" | Right -> "right"
+type focus = Focus_kind
+type move = Move_kind
+
+type 'kind target =
+  | Prev : 'kind target
+  | Next : 'kind target
+  | Index : int -> focus target
+
+let restrict_move_target : 'k target -> move target option = function
+  | Index _ -> None
+  | Next -> Some Next
+  | Prev -> Some Prev
+
+let target_of_string_opt = function
+  | "prev" -> Some Prev
+  | "next" -> Some Next
+  | x ->
+      Option.bind (int_of_string_opt x) @@ fun x ->
+      if 0 <= x then Some (Index x) else None
+
+let target_to_string : type kind. kind target -> string = function
+  | Prev -> "prev"
+  | Next -> "next"
+  | Index x -> string_of_int x
 
 type switch = On | Off | Toggle
 
@@ -36,8 +52,8 @@ let operation_of_string_opt = function
 let operation_to_string = function Incr -> "increment" | Decr -> "decrement"
 
 type command =
-  | Focus of direction
-  | Move of direction
+  | Focus of focus target
+  | Move of move target
   | Maximize of switch
   | Split of operation
 
@@ -47,8 +63,10 @@ let command_of_string str =
   String.split_on_char ' ' str
   |> List.filter (function "" -> false | _ -> true)
   |> function
-  | [ "focus"; dir ] -> (fun x -> Focus x) <$> direction_of_string_opt dir
-  | [ "move"; dir ] -> (fun x -> Move x) <$> direction_of_string_opt dir
+  | [ "focus"; target ] -> (fun x -> Focus x) <$> target_of_string_opt target
+  | [ "move"; target ] ->
+      Option.bind (target_of_string_opt target) @@ fun target ->
+      (fun x -> Move x) <$> restrict_move_target target
   | [ "maximize"; switch ] ->
       (fun x -> Maximize x) <$> switch_of_string_opt switch
   | [ "split"; op ] -> (fun x -> Split x) <$> operation_of_string_opt op
@@ -60,8 +78,8 @@ let command_of_string_exn str =
   | None -> raise (Invalid_argument "Spatial_ipc.command_of_string_exn")
 
 let command_to_string = function
-  | Focus dir -> Format.sprintf "focus %s" (direction_to_string dir)
-  | Move dir -> Format.sprintf "move %s" (direction_to_string dir)
+  | Focus dir -> Format.sprintf "focus %s" (target_to_string dir)
+  | Move dir -> Format.sprintf "move %s" (target_to_string dir)
   | Maximize switch -> Format.sprintf "maximize %s" (switch_to_string switch)
   | Split op -> Format.sprintf "split %s" (operation_to_string op)
 
diff --git a/lib/spatial_ipc/spatial_ipc.mli b/lib/spatial_ipc/spatial_ipc.mli
index d742867..6a00c14 100644
--- a/lib/spatial_ipc/spatial_ipc.mli
+++ b/lib/spatial_ipc/spatial_ipc.mli
@@ -4,13 +4,20 @@
 
 val socket_path : string
 
-type direction = Left | Right
+type focus = Focus_kind
+type move = Move_kind
+
+type 'kind target =
+  | Prev : 'kind target
+  | Next : 'kind target
+  | Index : int -> focus target
+
 type switch = On | Off | Toggle
 type operation = Incr | Decr
 
 type command =
-  | Focus of direction
-  | Move of direction
+  | Focus of focus target
+  | Move of move target
   | Maximize of switch
   | Split of operation