open Core.Std;;
open Qptypes;;

type t = (Gto.t * Atom_number.t) list;;

(** Read all the basis functions of an element *)
let read in_channel at_number =
  let rec read result =
    try
      let gto = Gto.read_one in_channel in
      read ( (gto,at_number)::result)
    with
    | Gto.End_Of_Basis -> List.rev result
  in read []  
;;

(** Find an element in the basis set file *)
let find in_channel element =
  In_channel.seek in_channel 0L;
  let element_read = ref Element.X in
  while !element_read <> element
  do
    let buffer = input_line in_channel in
    try
      element_read := Element.of_string buffer
    with
    | Element.ElementError _ -> ()
  done ;
  !element_read
;;

(** Read an element from the file *)
let read_element in_channel at_number element =
  ignore (find in_channel element) ;
  read in_channel at_number ;
;;

let to_string b =
  List.map ~f:(fun (g,n) ->
     let n = Atom_number.to_int n in
     (Int.to_string n)^":"^(Gto.to_string g)) b
  |> String.concat ~sep:"\n"
;;