sidereal

-module(calendar@date).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch, inline]).
-define(FILEPATH, "src/calendar/date.gleam").
-export([is_leap_year/1, days_in_month/2, new/4, new_simple/3, new_iso/3, to_string/1, to_iso8601/1, compare/2, add_days/2, subtract_days/2, from_timestamp/1, from_days_since_unix_epoch/2, to_timestamp/1, utc_today_with_calendar/1, utc_today/0, leap_year/1, days_in_month_for_date/1, months_in_year/1, to_iso8601_with_format/2, to_erl/1, from_erl_with_calendar/2, from_erl/1, from_gregorian_days_with_calendar/2, from_gregorian_days/1, to_gregorian_days/1, before/2, 'after'/2, convert/2, add/2, diff/2, shift/2, day_of_week_starting_on/2, day_of_week/1, beginning_of_week_starting_on/2, beginning_of_week/1, end_of_week_starting_on/2, end_of_week/1, day_of_year/1, quarter_of_year/1, year_of_era/1, day_of_era/1, beginning_of_month/1, end_of_month/1, from_iso8601_with_calendar/2, from_iso8601/1, range_with_step/3, range/2]).
-export_type([date/0, date_error/0, date_format/0]).

-if(?OTP_RELEASE >= 27).
-define(MODULEDOC(Str), -moduledoc(Str)).
-define(DOC(Str), -doc(Str)).
-else.
-define(MODULEDOC(Str), -compile([])).
-define(DOC(Str), -compile([])).
-endif.

-type date() :: {date, integer(), integer(), integer(), binary()}.

-type date_error() :: invalid_date |
    invalid_year |
    invalid_month |
    invalid_day |
    invalid_format |
    invalid_calendar |
    incompatible_calendars.

-type date_format() :: extended | basic.

-file("src/calendar/date.gleam", 63).
?DOC(" Checks if a year is a leap year.\n").
-spec is_leap_year(integer()) -> boolean().
is_leap_year(Year) ->
    case (Year rem 4) =:= 0 of
        true ->
            case (Year rem 100) =:= 0 of
                true ->
                    (Year rem 400) =:= 0;

                false ->
                    true
            end;

        false ->
            false
    end.

-file("src/calendar/date.gleam", 75).
?DOC(" Returns the number of days in a given month and year.\n").
-spec days_in_month(integer(), integer()) -> integer().
days_in_month(Year, Month) ->
    case Month of
        1 ->
            31;

        3 ->
            31;

        5 ->
            31;

        7 ->
            31;

        8 ->
            31;

        10 ->
            31;

        12 ->
            31;

        4 ->
            30;

        6 ->
            30;

        9 ->
            30;

        11 ->
            30;

        2 ->
            case is_leap_year(Year) of
                true ->
                    29;

                false ->
                    28
            end;

        _ ->
            0
    end.

-file("src/calendar/date.gleam", 89).
?DOC(" Validates if the given date components form a valid date.\n").
-spec is_valid_date(integer(), integer(), integer()) -> boolean().
is_valid_date(Year, Month, Day) ->
    (((Month >= 1) andalso (Month =< 12)) andalso (Day >= 1)) andalso (Day =< days_in_month(
        Year,
        Month
    )).

-file("src/calendar/date.gleam", 40).
?DOC(" Creates a new Date struct.\n").
-spec new(integer(), integer(), integer(), binary()) -> {ok, date()} |
    {error, date_error()}.
new(Year, Month, Day, Calendar) ->
    case is_valid_date(Year, Month, Day) of
        true ->
            {ok, {date, Year, Month, Day, Calendar}};

        false ->
            {error, invalid_date}
    end.

-file("src/calendar/date.gleam", 53).
?DOC(" Creates a new Date struct with ISO calendar as default.\n").
-spec new_simple(integer(), integer(), integer()) -> {ok, date()} |
    {error, date_error()}.
new_simple(Year, Month, Day) ->
    new(Year, Month, Day, <<"Calendar.ISO"/utf8>>).

-file("src/calendar/date.gleam", 58).
?DOC(" Creates a new Date struct with ISO calendar as default.\n").
-spec new_iso(integer(), integer(), integer()) -> {ok, date()} |
    {error, date_error()}.
new_iso(Year, Month, Day) ->
    new(Year, Month, Day, <<"Calendar.ISO"/utf8>>).

-file("src/calendar/date.gleam", 106).
?DOC(" Helper function to pad string with leading characters.\n").
-spec pad_left(binary(), integer(), binary()) -> binary().
pad_left(Str, Width, Pad_char) ->
    Current_length = string:length(Str),
    case Current_length >= Width of
        true ->
            Str;

        false ->
            <<(gleam@string:repeat(Pad_char, Width - Current_length))/binary,
                Str/binary>>
    end.

-file("src/calendar/date.gleam", 94).
?DOC(" Converts a Date to a string in ISO8601 format (YYYY-MM-DD).\n").
-spec to_string(date()) -> binary().
to_string(Date) ->
    Year_str = case (erlang:element(2, Date) >= 0) andalso (erlang:element(
        2,
        Date
    )
    =< 9999) of
        true ->
            pad_left(
                erlang:integer_to_binary(erlang:element(2, Date)),
                4,
                <<"0"/utf8>>
            );

        false ->
            erlang:integer_to_binary(erlang:element(2, Date))
    end,
    Month_str = pad_left(
        erlang:integer_to_binary(erlang:element(3, Date)),
        2,
        <<"0"/utf8>>
    ),
    Day_str = pad_left(
        erlang:integer_to_binary(erlang:element(4, Date)),
        2,
        <<"0"/utf8>>
    ),
    <<<<<<<<Year_str/binary, "-"/utf8>>/binary, Month_str/binary>>/binary,
            "-"/utf8>>/binary,
        Day_str/binary>>.

-file("src/calendar/date.gleam", 115).
?DOC(" Converts a Date to ISO8601 format.\n").
-spec to_iso8601(date()) -> binary().
to_iso8601(Date) ->
    to_string(Date).

-file("src/calendar/date.gleam", 139).
?DOC(" Convert date to days since Unix epoch (1970-01-01).\n").
-spec to_days_since_epoch(date()) -> integer().
to_days_since_epoch(Date) ->
    calendar@iso:date_to_iso_days(
        erlang:element(2, Date),
        erlang:element(3, Date),
        erlang:element(4, Date)
    )
    - 719528.

-file("src/calendar/date.gleam", 131).
?DOC(" Compare two dates. Returns order.Lt, order.Eq, or order.Gt.\n").
-spec compare(date(), date()) -> gleam@order:order().
compare(Date1, Date2) ->
    Days1 = to_days_since_epoch(Date1),
    Days2 = to_days_since_epoch(Date2),
    gleam@int:compare(Days1, Days2).

-file("src/calendar/date.gleam", 144).
?DOC(" Convert days since epoch back to a date.\n").
-spec from_days_since_epoch(integer(), binary()) -> {ok, date()} |
    {error, date_error()}.
from_days_since_epoch(Days, Calendar) ->
    Iso_days = Days + 719528,
    {Year, Month, Day} = calendar@iso:date_from_iso_days(Iso_days),
    case is_valid_date(Year, Month, Day) of
        true ->
            {ok, {date, Year, Month, Day, Calendar}};

        false ->
            {error, invalid_date}
    end.

-file("src/calendar/date.gleam", 120).
?DOC(" Add days to a date.\n").
-spec add_days(date(), integer()) -> {ok, date()} | {error, date_error()}.
add_days(Date, Days) ->
    Total_days = to_days_since_epoch(Date) + Days,
    from_days_since_epoch(Total_days, erlang:element(5, Date)).

-file("src/calendar/date.gleam", 126).
?DOC(" Subtract days from a date.\n").
-spec subtract_days(date(), integer()) -> {ok, date()} | {error, date_error()}.
subtract_days(Date, Days) ->
    add_days(Date, - Days).

-file("src/calendar/date.gleam", 177).
-spec leap_day_offset(integer()) -> integer().
leap_day_offset(Year) ->
    case is_leap_year(Year) of
        true ->
            1;

        false ->
            0
    end.

-file("src/calendar/date.gleam", 159).
?DOC(" Convert month to approximate day of year.\n").
-spec month_to_day_of_year(integer(), integer()) -> integer().
month_to_day_of_year(Year, Month) ->
    case Month of
        1 ->
            0;

        2 ->
            31;

        3 ->
            59 + leap_day_offset(Year);

        4 ->
            90 + leap_day_offset(Year);

        5 ->
            120 + leap_day_offset(Year);

        6 ->
            151 + leap_day_offset(Year);

        7 ->
            181 + leap_day_offset(Year);

        8 ->
            212 + leap_day_offset(Year);

        9 ->
            243 + leap_day_offset(Year);

        10 ->
            273 + leap_day_offset(Year);

        11 ->
            304 + leap_day_offset(Year);

        12 ->
            334 + leap_day_offset(Year);

        _ ->
            0
    end.

-file("src/calendar/date.gleam", 185).
?DOC(" Create a date from Unix timestamp (seconds since epoch).\n").
-spec from_timestamp(integer()) -> {ok, date()} | {error, date_error()}.
from_timestamp(Timestamp) ->
    from_days_since_epoch(Timestamp div 86400, <<"Calendar.ISO"/utf8>>).

-file("src/calendar/date.gleam", 190).
?DOC(" Create a date from days since Unix epoch (1970-01-01).\n").
-spec from_days_since_unix_epoch(integer(), binary()) -> {ok, date()} |
    {error, date_error()}.
from_days_since_unix_epoch(Days, Calendar) ->
    from_days_since_epoch(Days, Calendar).

-file("src/calendar/date.gleam", 198).
?DOC(" Convert date to Unix timestamp (approximation).\n").
-spec to_timestamp(date()) -> integer().
to_timestamp(Date) ->
    to_days_since_epoch(Date) * 86400.

-file("src/calendar/date.gleam", 208).
?DOC(" Returns the current date in UTC with specified calendar.\n").
-spec utc_today_with_calendar(binary()) -> date().
utc_today_with_calendar(Calendar) ->
    Timestamp = os:system_time(),
    Days = Timestamp div 86400,
    case from_days_since_epoch(Days, Calendar) of
        {ok, Date} ->
            Date;

        {error, _} ->
            {date, 1970, 1, 1, Calendar}
    end.

-file("src/calendar/date.gleam", 203).
?DOC(" Returns the current date in UTC.\n").
-spec utc_today() -> date().
utc_today() ->
    utc_today_with_calendar(<<"Calendar.ISO"/utf8>>).

-file("src/calendar/date.gleam", 218).
?DOC(" Returns `true` if the year in the given `date` is a leap year.\n").
-spec leap_year(date()) -> boolean().
leap_year(Date) ->
    is_leap_year(erlang:element(2, Date)).

-file("src/calendar/date.gleam", 223).
?DOC(" Returns the number of days in the given `date` month.\n").
-spec days_in_month_for_date(date()) -> integer().
days_in_month_for_date(Date) ->
    days_in_month(erlang:element(2, Date), erlang:element(3, Date)).

-file("src/calendar/date.gleam", 228).
?DOC(" Returns the number of months in the given `date` year.\n").
-spec months_in_year(date()) -> integer().
months_in_year(_) ->
    12.

-file("src/calendar/date.gleam", 247).
?DOC(" Converts the given `date` to ISO 8601 with format option.\n").
-spec to_iso8601_with_format(date(), date_format()) -> binary().
to_iso8601_with_format(Date, Format) ->
    case Format of
        extended ->
            to_string(Date);

        basic ->
            Year_str = case (erlang:element(2, Date) >= 0) andalso (erlang:element(
                2,
                Date
            )
            =< 9999) of
                true ->
                    pad_left(
                        erlang:integer_to_binary(erlang:element(2, Date)),
                        4,
                        <<"0"/utf8>>
                    );

                false ->
                    erlang:integer_to_binary(erlang:element(2, Date))
            end,
            Month_str = pad_left(
                erlang:integer_to_binary(erlang:element(3, Date)),
                2,
                <<"0"/utf8>>
            ),
            Day_str = pad_left(
                erlang:integer_to_binary(erlang:element(4, Date)),
                2,
                <<"0"/utf8>>
            ),
            <<<<Year_str/binary, Month_str/binary>>/binary, Day_str/binary>>
    end.

-file("src/calendar/date.gleam", 263).
?DOC(" Converts the given `date` to an Erlang date tuple.\n").
-spec to_erl(date()) -> {integer(), integer(), integer()}.
to_erl(Date) ->
    {erlang:element(2, Date), erlang:element(3, Date), erlang:element(4, Date)}.

-file("src/calendar/date.gleam", 273).
?DOC(" Converts an Erlang date tuple to a `Date` struct with specified calendar.\n").
-spec from_erl_with_calendar({integer(), integer(), integer()}, binary()) -> {ok,
        date()} |
    {error, date_error()}.
from_erl_with_calendar(Tuple, Calendar) ->
    {Year, Month, Day} = Tuple,
    new(Year, Month, Day, Calendar).

-file("src/calendar/date.gleam", 268).
?DOC(" Converts an Erlang date tuple to a `Date` struct.\n").
-spec from_erl({integer(), integer(), integer()}) -> {ok, date()} |
    {error, date_error()}.
from_erl(Tuple) ->
    from_erl_with_calendar(Tuple, <<"Calendar.ISO"/utf8>>).

-file("src/calendar/date.gleam", 287).
?DOC(" Converts a number of gregorian days to a `Date` struct with specified calendar.\n").
-spec from_gregorian_days_with_calendar(integer(), binary()) -> date().
from_gregorian_days_with_calendar(Days, Calendar) ->
    case from_days_since_epoch(Days - 719163, Calendar) of
        {ok, Date} ->
            Date;

        {error, _} ->
            {date, 0, 1, 1, Calendar}
    end.

-file("src/calendar/date.gleam", 282).
?DOC(" Converts a number of gregorian days to a `Date` struct.\n").
-spec from_gregorian_days(integer()) -> date().
from_gregorian_days(Days) ->
    from_gregorian_days_with_calendar(Days, <<"Calendar.ISO"/utf8>>).

-file("src/calendar/date.gleam", 296).
?DOC(" Converts a `date` struct to a number of gregorian days.\n").
-spec to_gregorian_days(date()) -> integer().
to_gregorian_days(Date) ->
    to_days_since_epoch(Date) + 719163.

-file("src/calendar/date.gleam", 302).
?DOC(" Returns `true` if the first date is strictly earlier than the second.\n").
-spec before(date(), date()) -> boolean().
before(Date1, Date2) ->
    case compare(Date1, Date2) of
        lt ->
            true;

        _ ->
            false
    end.

-file("src/calendar/date.gleam", 310).
?DOC(" Returns `true` if the first date is strictly later than the second.\n").
-spec 'after'(date(), date()) -> boolean().
'after'(Date1, Date2) ->
    case compare(Date1, Date2) of
        gt ->
            true;

        _ ->
            false
    end.

-file("src/calendar/date.gleam", 318).
?DOC(" Converts the given `date` from its calendar to the given `calendar`.\n").
-spec convert(date(), binary()) -> {ok, date()} | {error, date_error()}.
convert(Date, Target_calendar) ->
    case erlang:element(5, Date) =:= Target_calendar of
        true ->
            {ok, Date};

        false ->
            {ok,
                {date,
                    erlang:element(2, Date),
                    erlang:element(3, Date),
                    erlang:element(4, Date),
                    Target_calendar}}
    end.

-file("src/calendar/date.gleam", 334).
?DOC(" Adds the number of days to the given `date`.\n").
-spec add(date(), integer()) -> date().
add(Date, Days) ->
    case add_days(Date, Days) of
        {ok, New_date} ->
            New_date;

        {error, _} ->
            Date
    end.

-file("src/calendar/date.gleam", 343).
?DOC(" Calculates the difference between two dates, in a full number of days.\n").
-spec diff(date(), date()) -> integer().
diff(Date1, Date2) ->
    to_days_since_epoch(Date1) - to_days_since_epoch(Date2).

-file("src/calendar/date.gleam", 348).
?DOC(" Shifts given `date` by `duration` according to its calendar.\n").
-spec shift(date(), calendar@duration:duration()) -> {ok, date()} |
    {error, date_error()}.
shift(Date, Duration) ->
    Years = erlang:element(2, Duration),
    Months = erlang:element(3, Duration),
    Weeks = erlang:element(4, Duration),
    Days = erlang:element(5, Duration),
    New_year = erlang:element(2, Date) + Years,
    New_month = erlang:element(3, Date) + Months,
    Normalized_year = New_year + ((New_month - 1) div 12),
    Normalized_month = ((New_month - 1) rem 12) + 1,
    Max_days = days_in_month(Normalized_year, Normalized_month),
    Normalized_day = case erlang:element(4, Date) > Max_days of
        true ->
            Max_days;

        false ->
            erlang:element(4, Date)
    end,
    case new(
        Normalized_year,
        Normalized_month,
        Normalized_day,
        erlang:element(5, Date)
    ) of
        {ok, Intermediate_date} ->
            Total_days = (Weeks * 7) + Days,
            add_days(Intermediate_date, Total_days);

        {error, E} ->
            {error, E}
    end.

-file("src/calendar/date.gleam", 391).
?DOC(" Calculates the ordinal day of the week with custom starting day.\n").
-spec day_of_week_starting_on(date(), integer()) -> integer().
day_of_week_starting_on(Date, Starting_on) ->
    Year = case erlang:element(3, Date) < 3 of
        true ->
            erlang:element(2, Date) - 1;

        false ->
            erlang:element(2, Date)
    end,
    Month = case erlang:element(3, Date) < 3 of
        true ->
            erlang:element(3, Date) + 12;

        false ->
            erlang:element(3, Date)
    end,
    Day_of_week = (((((erlang:element(4, Date) + ((13 * (Month + 1)) div 5)) + Year)
    + (Year div 4))
    - (Year div 100))
    + (Year div 400))
    rem 7,
    Adjusted = case Day_of_week of
        0 ->
            7;

        N ->
            N
    end,
    case (Adjusted - Starting_on) + 1 of
        N@1 when N@1 =< 0 ->
            N@1 + 7;

        N@2 when N@2 > 7 ->
            N@2 - 7;

        N@3 ->
            N@3
    end.

-file("src/calendar/date.gleam", 385).
?DOC(" Calculates the ordinal day of the week of a given `date`.\n").
-spec day_of_week(date()) -> integer().
day_of_week(Date) ->
    day_of_week_starting_on(Date, 1).

-file("src/calendar/date.gleam", 439).
?DOC(" Calculates beginning of week with custom starting day.\n").
-spec beginning_of_week_starting_on(date(), integer()) -> date().
beginning_of_week_starting_on(Date, Starting_on) ->
    Current_day_of_week = day_of_week_starting_on(Date, Starting_on),
    Days_to_subtract = Current_day_of_week - 1,
    add(Date, - Days_to_subtract).

-file("src/calendar/date.gleam", 433).
?DOC(" Calculates a date that is the first day of the week for the given `date`.\n").
-spec beginning_of_week(date()) -> date().
beginning_of_week(Date) ->
    beginning_of_week_starting_on(Date, 1).

-file("src/calendar/date.gleam", 452).
?DOC(" Calculates end of week with custom starting day.\n").
-spec end_of_week_starting_on(date(), integer()) -> date().
end_of_week_starting_on(Date, Starting_on) ->
    Current_day_of_week = day_of_week_starting_on(Date, Starting_on),
    Days_to_add = 7 - Current_day_of_week,
    add(Date, Days_to_add).

-file("src/calendar/date.gleam", 446).
?DOC(" Calculates a date that is the last day of the week for the given `date`.\n").
-spec end_of_week(date()) -> date().
end_of_week(Date) ->
    end_of_week_starting_on(Date, 1).

-file("src/calendar/date.gleam", 459).
?DOC(" Calculates the day of the year of a given `date`.\n").
-spec day_of_year(date()) -> integer().
day_of_year(Date) ->
    month_to_day_of_year(erlang:element(2, Date), erlang:element(3, Date)) + erlang:element(
        4,
        Date
    ).

-file("src/calendar/date.gleam", 464).
?DOC(" Calculates the quarter of the year of a given `date`.\n").
-spec quarter_of_year(date()) -> integer().
quarter_of_year(Date) ->
    case erlang:element(3, Date) of
        1 ->
            1;

        2 ->
            1;

        3 ->
            1;

        4 ->
            2;

        5 ->
            2;

        6 ->
            2;

        7 ->
            3;

        8 ->
            3;

        9 ->
            3;

        10 ->
            4;

        11 ->
            4;

        12 ->
            4;

        _ ->
            1
    end.

-file("src/calendar/date.gleam", 475).
?DOC(" Calculates the year-of-era and era for a given calendar year.\n").
-spec year_of_era(date()) -> {integer(), integer()}.
year_of_era(Date) ->
    case erlang:element(2, Date) >= 1 of
        true ->
            {erlang:element(2, Date), 1};

        false ->
            {- erlang:element(2, Date) + 1, 0}
    end.

-file("src/calendar/date.gleam", 485).
?DOC(" Calculates the day-of-era and era for a given calendar `date`.\n").
-spec day_of_era(date()) -> {integer(), integer()}.
day_of_era(Date) ->
    {_, Era} = year_of_era(Date),
    Days = to_gregorian_days(Date),
    case Era of
        1 ->
            {Days, 1};

        0 ->
            {- Days + 1, 0};

        _ ->
            {Days, Era}
    end.

-file("src/calendar/date.gleam", 498).
?DOC(" Calculates a date that is the first day of the month for the given `date`.\n").
-spec beginning_of_month(date()) -> date().
beginning_of_month(Date) ->
    {date,
        erlang:element(2, Date),
        erlang:element(3, Date),
        1,
        erlang:element(5, Date)}.

-file("src/calendar/date.gleam", 503).
?DOC(" Calculates a date that is the last day of the month for the given `date`.\n").
-spec end_of_month(date()) -> date().
end_of_month(Date) ->
    Last_day = days_in_month(erlang:element(2, Date), erlang:element(3, Date)),
    {date,
        erlang:element(2, Date),
        erlang:element(3, Date),
        Last_day,
        erlang:element(5, Date)}.

-file("src/calendar/date.gleam", 541).
-spec parse_iso8601_date(binary(), binary()) -> {ok, date()} |
    {error, date_error()}.
parse_iso8601_date(String, Calendar) ->
    case gleam@string:split(String, <<"-"/utf8>>) of
        [Year_str, Month_str, Day_str] ->
            case {gleam_stdlib:parse_int(Year_str),
                gleam_stdlib:parse_int(Month_str),
                gleam_stdlib:parse_int(Day_str)} of
                {{ok, Year}, {ok, Month}, {ok, Day}} ->
                    new(Year, Month, Day, Calendar);

                {_, _, _} ->
                    {error, invalid_format}
            end;

        _ ->
            {error, invalid_format}
    end.

-file("src/calendar/date.gleam", 239).
?DOC(" Parses an ISO 8601 date string with specified calendar.\n").
-spec from_iso8601_with_calendar(binary(), binary()) -> {ok, date()} |
    {error, date_error()}.
from_iso8601_with_calendar(String, Calendar) ->
    parse_iso8601_date(String, Calendar).

-file("src/calendar/date.gleam", 234).
?DOC(" Parses an ISO 8601 date string.\n").
-spec from_iso8601(binary()) -> {ok, date()} | {error, date_error()}.
from_iso8601(String) ->
    from_iso8601_with_calendar(String, <<"Calendar.ISO"/utf8>>).

-file("src/calendar/date.gleam", 557).
-spec generate_date_range(date(), integer(), integer(), integer(), list(date())) -> {ok,
        list(date())} |
    {error, date_error()}.
generate_date_range(Current, Current_days, Target_days, Step, Acc) ->
    case ((Step > 0) andalso (Current_days > Target_days)) orelse ((Step < 0)
    andalso (Current_days < Target_days)) of
        true ->
            {ok, lists:reverse(Acc)};

        false ->
            New_acc = [Current | Acc],
            case from_days_since_epoch(
                Current_days + Step,
                erlang:element(5, Current)
            ) of
                {ok, Next_date} ->
                    generate_date_range(
                        Next_date,
                        Current_days + Step,
                        Target_days,
                        Step,
                        New_acc
                    );

                {error, E} ->
                    {error, E}
            end
    end.

-file("src/calendar/date.gleam", 519).
?DOC(" Creates a date range with a step.\n").
-spec range_with_step(date(), date(), integer()) -> {ok, list(date())} |
    {error, date_error()}.
range_with_step(First, Last, Step) ->
    case Step =:= 0 of
        true ->
            {error, invalid_date};

        false ->
            case erlang:element(5, First) =:= erlang:element(5, Last) of
                false ->
                    {error, incompatible_calendars};

                true ->
                    First_days = to_days_since_epoch(First),
                    Last_days = to_days_since_epoch(Last),
                    generate_date_range(First, First_days, Last_days, Step, [])
            end
    end.

-file("src/calendar/date.gleam", 514).
?DOC(" Creates a date range between two dates.\n").
-spec range(date(), date()) -> {ok, list(date())} | {error, date_error()}.
range(First, Last) ->
    range_with_step(First, Last, 1).