-module(ranged_int@utils).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch]).

-export([overflow/3]).
-export_type([overflow/0]).

-type overflow() :: {would_overflow, bigi:big_int()} |
    {would_underflow, bigi:big_int()}.

-spec overflow(overflow(), bigi:big_int(), bigi:big_int()) -> bigi:big_int().
overflow(Overflow, Min, Max) ->
    Total_values = begin
        _pipe = bigi_ffi:subtract(Max, Min),
        bigi_ffi:add(_pipe, bigi_ffi:from(1))
    end,
    Actual = case Overflow of
        {would_overflow, Amount} ->
            bigi_ffi:add(Max, Amount);

        {would_underflow, Amount@1} ->
            bigi_ffi:subtract(Min, Amount@1)
    end,
    _pipe@1 = Actual,
    _pipe@2 = bigi_ffi:subtract(_pipe@1, Min),
    _pipe@3 = bigi_ffi:modulo(_pipe@2, Total_values),
    bigi_ffi:add(_pipe@3, Min).