feat: add support for rendering text (i.e. tabs)

This allows to have differences between the "raw" content of the buffer
and its visualization on screen. At the time of writing this handles the
rendering of tabs (i.e. '\t') as a fixed amount of spaces, but will be
useful for syntax highlighting as well.

1 files changed, 14 insertions, 2 deletions

diff --git a/lib/editor.ml b/lib/editor.ml
index f91e66d..69dc666 100644
--- a/lib/editor.ml
+++ b/lib/editor.ml
@@ -11,6 +11,7 @@ type editor = {
   offset : int * int;
   cursor : cursor;
   buffer : Buffer.t option;
+  rendered : bool;
   pending : Key.t Sequence.t;
   i_pending : Command.t Sequence.t;
   n_pending : Command.t Sequence.t;
@@ -25,6 +26,7 @@ let init (c : Config.t) : editor =
     offset = (0, 0);
     cursor = (1, 1);
     buffer = List.hd c.files |> Option.map ~f:Buffer.from_file;
+    rendered = true;
     pending = Key.stream;
     i_pending = Command.i_stream;
     n_pending = Command.n_stream;
@@ -104,10 +106,13 @@ module Action = struct
     let aux e =
       let x, y = e.offset
       and ((r, c) as size) = e.term.size
-      and fill = Sequence.singleton '~' in
+      and fill = Sequence.singleton '~'
+      and limit =
+        Buffer.(if e.rendered then rendered_view else unrendered_view)
+      in
       let view =
         Option.(
-          e.buffer >>| Buffer.view x y r c
+          e.buffer >>| limit x y r c
           |> value ~default:(welcome size)
           |> Text.extend ~fill r)
       in
@@ -117,6 +122,11 @@ module Action = struct
 
   (* TODO: save logic *)
   let quit n = Stdlib.exit n
+
+  (* Debug *)
+  let get_rendered e = (e.rendered, e)
+  let set_rendered r e = ((), { e with rendered = r })
+  let toggle_rendered = get_rendered >>| not >>= set_rendered
   let noop = return ()
 end
 
@@ -352,6 +362,8 @@ let handle_normal_command =
   (* | Key 's' -> *)
   (*     (Buffer.Action.delete_after |> on_focused_buffer_or_new) *)
   (* *> set_mode Insert *)
+  (* Debug *)
+  | Simple (Ctrl 'R') -> toggle_rendered
   | _ -> noop
 
 let handle_next_command m e =