3 files changed, 125 insertions, 62 deletions

diff --git a/lib/command.ml b/lib/command.ml
index 7dedc6c..97c1fdf 100644
--- a/lib/command.ml
+++ b/lib/command.ml
@@ -3,19 +3,30 @@ open Key
 
 type register = char option
 type count = int option
-type operation = Noop | Yank | Paste | Delete | Change
+
+type operation =
+  | Noop
+  | Yank
+  | Delete
+  | Change
+  | Join
+  | Paste_before
+  | Paste_after
+  | Erase_before
+  | Erase_after
+
 type scope = Line | To_bol | To_eol | Down | Left | Right | Up
 
 type command =
   | Type of char
   | Simple of Key.t
   | Partial of Key.t
-  | Shortcut of register * count * operation * scope
+  | Shortcut of register * count * operation
   | Chord of register * count * operation * count * scope
 
 type t = command
 
-let shortcut ?r ?n c s = Shortcut (r, n, c, s)
+let shortcut ?r ?n c = Shortcut (r, n, c)
 let chord ?r ?n1 c ?n2 m = Chord (r, n1, c, n2, m)
 
 let i_stream =
@@ -42,6 +53,11 @@ let simple_movements =
     Backspace;
   ]
 
+let instant_operation =
+  [ Key 'C'; Key 'D'; Key 'J'; Key 'P'; Key 'X'; Key 'p'; Key 'x' ]
+
+let chord_operation = [ Key 'c'; Key 'd'; Key 'y' ]
+
 let to_scope = function
   | Key 'j' | Arrow_down -> Down
   | Key 'h' | Arrow_left | Backspace -> Left
@@ -52,61 +68,71 @@ let to_scope = function
 let n_stream =
   let step s k =
     let open Sequence.Step in
-    let is_chord_op c = String.contains "ydc" (Char.lowercase c) in
+    let is_chord_operation k = List.mem ~equal:Poly.equal chord_operation k in
     let is_simple_movement k = List.mem ~equal:Poly.equal simple_movements k in
-    let to_op c =
-      match Char.lowercase c with
-      | 'y' -> Yank
-      | 'p' -> Paste
-      | 'd' -> Delete
-      | 'c' -> Change
+    let is_instant_operation k =
+      List.mem ~equal:Poly.equal instant_operation k
+    in
+    let to_op = function
+      | Key 'J' -> Join
+      | Key 'c' | Key 'C' -> Change
+      | Key 'd' | Key 'D' -> Delete
+      | Key 'y' | Key 'Y' -> Yank
+      | Key 'p' -> Paste_after
+      | Key 'P' -> Paste_before
+      | Key 'x' -> Erase_after
+      | Key 'X' -> Erase_before
       | _ -> failwith "Invalid operation in chord."
     in
     match (s, k) with
     | `start, Key '"' -> Yield { value = Partial k; state = `chord_reg_pre }
+    (* Register *)
     | `chord_reg_pre, Key c -> Yield { value = Partial k; state = `chord_reg c }
-    | `chord_reg r, Key n when Char.('1' <= n && n <= '9') ->
-        let n = Char.to_int n - 48 in
-        Yield { value = Partial k; state = `chord_n (Some r, n) }
+    (* Count (first) *)
     | `start, Key n when Char.('1' <= n && n <= '9') ->
         let n = Char.to_int n - 48 in
-        Yield { value = Partial k; state = `chord_n (None, n) }
-    | `chord_n (r, m), Key n when Char.('0' <= n && n <= '9') ->
+        Yield { value = Partial k; state = `chord_fst_n (None, n) }
+    | `chord_reg r, Key n when Char.('1' <= n && n <= '9') ->
+        let n = Char.to_int n - 48 in
+        Yield { value = Partial k; state = `chord_fst_n (Some r, n) }
+    | `chord_fst_n (r, m), Key n when Char.('0' <= n && n <= '9') ->
         let n = (10 * m) + Char.to_int n - 48 in
-        Yield { value = Partial k; state = `chord_n (r, n) }
-    | `start, Key c when is_chord_op c ->
-        if Char.is_uppercase c then
-          Yield { value = shortcut (to_op c) To_eol; state = `start }
-        else
-          Yield { value = Partial k; state = `chord_cmd (None, None, to_op c) }
-    | `chord_reg r, Key c when is_chord_op c ->
-        if Char.is_uppercase c then
-          Yield { value = shortcut ~r (to_op c) To_eol; state = `start }
-        else
-          Yield
-            { value = Partial k; state = `chord_cmd (Some r, None, to_op c) }
-    | `chord_n (r, n), Key c when is_chord_op c ->
-        if Char.is_uppercase c then
-          Yield { value = shortcut ?r ~n (to_op c) To_eol; state = `start }
-        else
-          Yield { value = Partial k; state = `chord_cmd (r, Some n, to_op c) }
-    | `chord_cmd (r, n, c), Key ch when is_chord_op ch && Poly.(c = to_op ch) ->
-        if Char.is_uppercase ch then
-          Yield { value = shortcut ?r ?n c To_bol; state = `start }
-        else Yield { value = shortcut ?r ?n c Line; state = `start }
+        Yield { value = Partial k; state = `chord_fst_n (r, n) }
+    (* Instant operations *)
+    | `start, k when is_instant_operation k ->
+        Yield { value = shortcut (to_op k); state = `start }
+    | `chord_reg r, k when is_instant_operation k ->
+        Yield { value = shortcut ~r (to_op k); state = `start }
+    | `chord_fst_n (r, n), k when is_instant_operation k ->
+        Yield { value = shortcut ?r ~n (to_op k); state = `start }
+    (* Chord operation (first) *)
+    | `start, k when is_chord_operation k ->
+        Yield { value = Partial k; state = `chord_cmd (None, None, to_op k) }
+    | `chord_reg r, k when is_chord_operation k ->
+        Yield { value = Partial k; state = `chord_cmd (Some r, None, to_op k) }
+    | `chord_fst_n (r, n), k when is_chord_operation k ->
+        Yield { value = Partial k; state = `chord_cmd (r, Some n, to_op k) }
+    (* Count (second) *)
+    | `chord_cmd (r, n1, c), Key n when Char.('1' <= n && n <= '9') ->
+        let n = Char.to_int n - 48 in
+        Yield { value = Partial k; state = `chord_snd_n (r, n1, c, n) }
+    | `chord_snd_n (r, n1, c, n2), Key n when Char.('0' <= n && n <= '9') ->
+        let n2 = (10 * n2) + Char.to_int n - 48 in
+        Yield { value = Partial k; state = `chord_snd_n (r, n1, c, n2) }
+    (* Chord operation (second) *)
+    | `chord_cmd (r, n, c), k when is_chord_operation k && Poly.(c = to_op k) ->
+        Yield { value = chord ?r ?n1:n c Line; state = `start }
+    | `chord_snd_n (r, n1, c, n2), k
+      when is_chord_operation k && Poly.(c = to_op k) ->
+        Yield { value = chord ?r ?n1 c ~n2 Line; state = `start }
+    (* Movement *)
     | (`start | `chord_reg _), k when is_simple_movement k ->
         Yield { value = chord Noop (to_scope k); state = `start }
-    | `chord_n (_, n), k when is_simple_movement k ->
+    | `chord_fst_n (_, n), k when is_simple_movement k ->
         Yield { value = chord ~n1:n Noop (to_scope k); state = `start }
     | `chord_cmd (r, n, c), k when is_simple_movement k ->
         Yield { value = chord ?r ?n1:n c (to_scope k); state = `start }
-    | `chord_cmd (r, n1, c), Key n when Char.('1' <= n && n <= '9') ->
-        let n = Char.to_int n - 48 in
-        Yield { value = Partial k; state = `chord_mv_n (r, n1, c, n) }
-    | `chord_mv_n (r, n1, c, n2), Key n when Char.('0' <= n && n <= '9') ->
-        let n2 = (10 * n2) + Char.to_int n - 48 in
-        Yield { value = Partial k; state = `chord_mv_n (r, n1, c, n2) }
-    | `chord_mv_n (r, n1, c, n2), k when is_simple_movement k ->
+    | `chord_snd_n (r, n1, c, n2), k when is_simple_movement k ->
         Yield { value = chord ?r ?n1 c ~n2 (to_scope k); state = `start }
     (* Catch-all rules *)
     | `start, _ -> Yield { value = Simple k; state = `start }
diff --git a/lib/editor.ml b/lib/editor.ml
index 2e031e1..adc9994 100644
--- a/lib/editor.ml
+++ b/lib/editor.ml
@@ -228,37 +228,68 @@ let handle_normal_command =
   (* | Key 'x' | Delete -> Buffer.Action.delete_after |> on_focused_buffer_or_new *)
   (* | Key 'X' -> Buffer.Action.delete_before |> on_focused_buffer_or_new *)
   (* | Key '$' -> Buffer.Action.eol |> on_focused_buffer_or_new *)
-  | Shortcut (_, n, Change, Line) ->
+  (* Change *)
+  | Shortcut (_, n, Change) ->
       let n = Option.value ~default:1 n - 1 in
+      (Buffer.Action.(
+         delete_to_eol &> move_down &> delete_lines ~n &> move_up &> eol)
+      |> on_focused_buffer_or_new)
+      *> set_mode Insert
+  | Chord (_, n1, Change, n2, Line) ->
+      let n = Option.((value ~default:1 n1 * value ~default:1 n2) - 1) in
+      (Buffer.Action.(delete_lines ~n &> bol &> delete_to_eol)
+      |> on_focused_buffer_or_new)
+      *> set_mode Insert
+  | Chord (_, n1, Change, n2, Down) ->
+      let n = Option.(value ~default:1 n1 * value ~default:1 n2) in
       (Buffer.Action.(delete_lines ~n &> bol &> delete_to_eol)
       |> on_focused_buffer_or_new)
       *> set_mode Insert
-  | Shortcut (_, _, Change, To_eol) ->
-      (Buffer.Action.delete_to_eol |> on_focused_buffer_or_new)
+  | Chord (_, n1, Change, n2, Left) ->
+      let n = Option.(value ~default:1 n1 * value ~default:1 n2) in
+      (Buffer.Action.delete_before ~n |> on_focused_buffer_or_new)
       *> set_mode Insert
-  | Shortcut (_, _, Change, To_bol) ->
-      (Buffer.Action.delete_to_bol |> on_focused_buffer_or_new)
+  | Chord (_, n1, Change, n2, Right) ->
+      let n = Option.(value ~default:1 n1 * value ~default:1 n2) in
+      (Buffer.Action.delete_after ~n |> on_focused_buffer_or_new)
+      *> set_mode Insert
+  | Chord (_, n1, Change, n2, Up) ->
+      let n = Option.(value ~default:1 n1 * value ~default:1 n2) in
+      (Buffer.Action.(bol &> delete_to_eol &> delete_lines_before ~n)
+      |> on_focused_buffer_or_new)
       *> set_mode Insert
   (* Delete *)
+  | Shortcut (_, n, Delete) ->
+      let n = Option.value ~default:1 n - 1 in
+      Buffer.Action.(
+        delete_to_eol &> move_down &> delete_lines ~n &> move_up &> eol)
+      |> on_focused_buffer_or_new
+  | Chord (_, n1, Delete, n2, Line) ->
+      let n = Option.(value ~default:1 n1 * value ~default:1 n2) in
+      Buffer.Action.delete_lines ~n |> on_focused_buffer_or_new
   | Chord (_, n1, Delete, n2, Down) ->
       let n = Option.((value ~default:1 n1 * value ~default:1 n2) + 1) in
       Buffer.Action.delete_lines ~n |> on_focused_buffer_or_new
   | Chord (_, n1, Delete, n2, Left) ->
       let n = Option.(value ~default:1 n1 * value ~default:1 n2) in
       Buffer.Action.delete_before ~n |> on_focused_buffer_or_new
+  | Shortcut (_, n, Erase_before) ->
+      let n = Option.(value ~default:1 n) in
+      Buffer.Action.delete_before ~n |> on_focused_buffer_or_new
   | Chord (_, n1, Delete, n2, Right) ->
       let n = Option.(value ~default:1 n1 * value ~default:1 n2) in
       Buffer.Action.delete_after ~n |> on_focused_buffer_or_new
+  | Shortcut (_, n, Erase_after) ->
+      let n = Option.(value ~default:1 n) in
+      Buffer.Action.delete_after ~n |> on_focused_buffer_or_new
   | Chord (_, n1, Delete, n2, Up) ->
-      let n = Option.((value ~default:1 n1 * value ~default:1 n2) + 1) in
-      Buffer.Action.delete_lines_before ~n |> on_focused_buffer_or_new
-  | Shortcut (_, n, Delete, Line) ->
-      Buffer.Action.delete_lines ~n:Option.(value ~default:1 n)
+      let n = Option.(value ~default:1 n1 * value ~default:1 n2) in
+      Buffer.Action.(delete_lines ~n:1 &> delete_lines_before ~n)
       |> on_focused_buffer_or_new
-  | Shortcut (_, _, Delete, To_eol) ->
-      Buffer.Action.delete_to_eol |> on_focused_buffer_or_new
-  | Shortcut (_, _, Delete, To_bol) ->
-      Buffer.Action.delete_to_bol |> on_focused_buffer_or_new
+  (* Join *)
+  | Shortcut (_, n, Join) ->
+      let n = Option.(value ~default:1 n) in
+      Buffer.Action.join_lines ~n |> on_focused_buffer_or_new
   | _ -> noop
 
 let handle_next_command m e =
diff --git a/lib/editorBuffer.ml b/lib/editorBuffer.ml
index b682116..ea89fb9 100644
--- a/lib/editorBuffer.ml
+++ b/lib/editorBuffer.ml
@@ -29,13 +29,12 @@ module Action = struct
   let bof = far_left |> on_content
   let eof = far_right |> on_content
   let insert k = map_focus (push k) |> on_content
+  (* let replace k = () *)
 
   let delete_after ?(cross_lines = false) ~n =
     let aux z =
       let line = focus_or ~default:Zipper.empty z in
       if cross_lines && is_far_right line && not (is_far_right z) then
-        (* let next = right z |> focus_or ~default:Zipper.empty |> far_left in *)
-        (* right z |> pop_after |> left |> map_focus (Fn.flip join next) *)
         pop_after z |> map_focus_or ~default:line (far_left &> join line)
       else map_focus pop_after z
     in
@@ -53,9 +52,7 @@ module Action = struct
   let delete_to_eol = map_focus (split &> fst) |> on_content
   let delete_to_bol = map_focus (split &> snd) |> on_content
   let delete_lines ~n = Fn.apply_n_times ~n pop_after |> on_content
-
-  let delete_lines_before ~n =
-    on_content (fun z -> pop_after z |> Fn.apply_n_times ~n:(n - 1) pop_before)
+  let delete_lines_before ~n = Fn.apply_n_times ~n pop_before |> on_content
 
   let newline =
     let aux z =
@@ -64,6 +61,15 @@ module Action = struct
     in
     on_content aux
 
+  let join_lines ~n =
+    let aux z =
+      if is_far_right z || is_far_right (right z) then z
+      else
+        let line = focus_or ~default:Zipper.empty z |> far_right in
+        pop_after z |> map_focus (far_left &> join line)
+    in
+    Fn.apply_n_times ~n aux |> on_content
+
   (* let save_history_to ?(clear = true) r = () *)
 end