%%%-------------------------------------------------------------------
%%% @author cheese
%%% @copyright (C) 2014, <COMPANY>
%%% @doc
%%%
%%% @end
%%% Created : 10. Dec 2014 2:21 PM
%%%-------------------------------------------------------------------
-module(protocol_iso_utilites).
-author("cheese").
-include("../../include/types_finance_protocol.hrl").

%% API
-export([get_field/2, set_field/2, prepare_data_string_to_bcd/1]).

%% Internal Functions
-export([internal_set_field/3]).


-spec(get_field([#iso_field{}], integer()) -> #iso_field{}).
get_field([], _Idx) ->
  undefined;
get_field([#iso_field{pos = Idx} = F | _Tail], Idx) ->
  F;
get_field([_Head | Tail], Idx) ->
  get_field(Tail, Idx).


-spec(set_field([#iso_field{}], #iso_field{}) -> #iso_field{}).
set_field(AllFields, Field) ->
  internal_set_field(AllFields, [], Field).


%%======================================================================================================================
internal_set_field([], Res, Field) ->
  Res ++ [Field];
internal_set_field([#iso_field{pos = Idx} | Res], Head, #iso_field{pos = Idx} = Field) ->
  Head ++ [Field] ++ Res;
internal_set_field([#iso_field{pos = IdxBefore} = FBefore | Tail], Res, #iso_field{pos = Idx} = Field) when IdxBefore > Idx ->
  Res ++ [Field] ++ [FBefore] ++ Tail;
internal_set_field([Head | Tail], Res, Field) ->
  internal_set_field(Tail, Res ++ [Head], Field).

-spec(prepare_data_string_to_bcd(string()) -> binary()).
prepare_data_string_to_bcd(String) ->
  bytes_extension:int_to_bcd(list_to_integer(String)).