Add help menu

1 files changed, 55 insertions, 0 deletions

diff --git a/lib/help_screen.ml b/lib/help_screen.ml
new file mode 100644
index 0000000..2f6fbaa
--- /dev/null
+++ b/lib/help_screen.ml
@@ -0,0 +1,55 @@
+module Common = Common
+open Notty
+
+type state = { go_back : unit -> unit }
+
+let info = [ "STITCH"; "Note composing tool" ]
+
+let render_info =
+  let title = I.strf ~attr:A.(st bold) "%s" "STITCH" |> I.pad ~l:2 ~t:1 in
+  let description =
+    I.strf ~attr:A.(st bold) "%s" "Small Note Composer" |> I.pad ~l:2 ~t:2
+  in
+  let keybindings = I.strf ~attr:A.(st bold) "%s" "Keybindings" |> I.pad ~l:2 ~t:4 in
+  let open I in
+  title </> description </> keybindings
+
+
+let help_menu =
+  [ "Toggle this menu", "?"
+  ; "Exit", "Ctrl-c, q, Esc"
+  ; "Toggle collapsed view", "@"
+  ; "Go down", "Ctrl-n, j"
+  ; "Go up", "Ctrl-p, k"
+  ; "Grep", "s"
+  ]
+
+
+let pad str n =
+  let padding = n - String.length str in
+  String.concat "" [ str; String.make padding ' ' ]
+
+
+let render_help_menu start_y =
+  let elements =
+    List.mapi
+      (fun i (explanation, keybinding) ->
+        let padding = pad explanation 30 in
+        I.strf "%s%s" padding keybinding |> I.pad ~l:2 ~t:(i + start_y))
+      help_menu
+  in
+  let open I in
+  List.fold_left (fun sum el -> el </> sum) I.empty elements
+
+
+let rec render t ({ go_back } as state) =
+  let img =
+    let open I in
+    render_info </> render_help_menu 5
+  in
+  Common.Term.image t img;
+  match Common.Term.event t with
+  | `End | `Key (`Escape, []) | `Key (`ASCII 'q', []) | `Key (`ASCII 'C', [ `Ctrl ]) -> ()
+  | `Resize _ -> render t state
+  | `Key (`ASCII '?', []) -> go_back ()
+  | _ -> render t state