gleastsq

-module(gleastsq@internal@params).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch]).

-export([decode_params/1]).
-export_type([fit_params/0]).

-type fit_params() :: {fit_params,
        gleam@option:option(integer()),
        gleam@option:option(float()),
        gleam@option:option(float()),
        gleam@option:option(float()),
        gleam@option:option(float()),
        gleam@option:option(float())}.

-spec do_decode_lm_params(
    list(gleastsq@options:least_square_options()),
    fit_params()
) -> fit_params().
do_decode_lm_params(Params, Acc) ->
    case Params of
        [] ->
            Acc;

        [{iterations, I} | Rest] ->
            do_decode_lm_params(Rest, erlang:setelement(2, Acc, {some, I}));

        [{epsilon, E} | Rest@1] ->
            do_decode_lm_params(Rest@1, erlang:setelement(3, Acc, {some, E}));

        [{tolerance, T} | Rest@2] ->
            do_decode_lm_params(Rest@2, erlang:setelement(4, Acc, {some, T}));

        [{damping, D} | Rest@3] ->
            do_decode_lm_params(Rest@3, erlang:setelement(5, Acc, {some, D}));

        [{damping_increase, Di} | Rest@4] ->
            do_decode_lm_params(Rest@4, erlang:setelement(6, Acc, {some, Di}));

        [{damping_decrease, Dd} | Rest@5] ->
            do_decode_lm_params(Rest@5, erlang:setelement(7, Acc, {some, Dd}))
    end.

-spec decode_params(list(gleastsq@options:least_square_options())) -> fit_params().
decode_params(Params) ->
    do_decode_lm_params(
        Params,
        {fit_params, none, none, none, none, none, none}
    ).