basic filter, sort, emit

lib/processing.ml

@@ -0,0 +1,59 @@
+open Types
+
+let ansi_filter s =
+  s |> function
+  | Ansi a ->
+      Types.Ansi
+        (List.filter
+           (function Types.Fg _ | Types.Bg _ -> false | _ -> true)
+           a)
+  | n -> n
+
+let permute order a = Array.mapi (fun i _ -> a.(order.(i))) a
+
+(* TODO: implement this so cli can use a dsl to specify colourising patterns *)
+type culr = {
+  colours : colour array;
+  sz : int;
+  mutable current : int;
+  mutable first : bool;
+}
+
+module Culriser = struct
+  type filter = (colour -> bool) list
+  type sort = int array
+
+  let run_filters f el =
+    List.fold_left (fun res filt -> if not (filt el) then false else res) true f
+
+  let create ?(s = [| 0; 1; 2; 3; 4; 5; 6; 7; 8; 9; 10; 11; 12; 13; 14; 15 |])
+      ?(f = []) c =
+    let colours =
+      c
+      |> List.fold_left
+           (fun acc el -> if run_filters f el then acc @ [ el ] else acc)
+           []
+      |> Array.of_list |> permute s
+    in
+    { colours; sz = Array.length colours; current = 0; first = true }
+
+  let next t =
+    let nv = t.current + 1 in
+    if nv >= t.sz then t.current <- 0 else t.current <- nv;
+    t.colours.(t.current)
+
+  let reset t = t.current <- 0
+
+  let add_colour t chunk =
+    if t.first then (
+      t.first <- false;
+      Ansi [ Fg (next t) ] :: [ chunk ])
+    else
+      match chunk with
+      | Separator _ -> chunk :: [ Ansi [ Fg (next t) ] ]
+      | Delimiter _ ->
+          reset t;
+          chunk :: [ Ansi [ Fg (next t) ] ]
+      | Ansi _ -> [ chunk ]
+      | Text _ -> [ chunk ]
+end