(** Document configuration from pre-scan.

    This module holds document-level settings extracted from file-local
    declarations such as #+TODO lines. These affect how the structural lexer and
    normalization interpret the document. *)

type todo_sequence = { active : string list; done_ : string list }
(** A TODO keyword sequence: active keywords followed by done keywords. *)

type t = {
  todo_sequences : todo_sequence list;
      (** All TODO keyword sequences declared in the file. Default: one sequence
          with active=["TODO"] done_=["DONE"]. *)
}
(** Document configuration. *)

(** The default configuration when no #+TODO declarations are present. *)
let default =
  { todo_sequences = [ { active = [ "TODO" ]; done_ = [ "DONE" ] } ] }

(** Return all TODO keywords (both active and done) from the config. *)
let all_todo_keywords config =
  List.concat_map (fun seq -> seq.active @ seq.done_) config.todo_sequences

(** Check if a word is a known TODO keyword. *)
let is_todo_keyword config word =
  List.exists
    (fun seq -> List.mem word seq.active || List.mem word seq.done_)
    config.todo_sequences