Files
ezic/src/ezic.erl

114 lines
2.5 KiB
Erlang

-module(ezic).
-include("include/ezic.hrl").
-export([
localtime/1
, utc_to_local/2
% , local_to_utc/2
% , zone_convert/3
, next_timechange/1
, next_timechange/2
]).
-export([load/1, dev_start/0, test/0]).
-define(gs2dt(X), calendar:gregorian_seconds_to_datetime(X)).
-define(dt2gs(X), calendar:datetime_to_gregorian_seconds(X)).
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% API
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
localtime(TzName) ->
utc_to_local(erlang:universaltime(), TzName).
utc_to_local(UTCDatetime, TzName) ->
{ok, Zone, Rule}= current_as_of_utc(UTCDatetime, TzName),
SecDiff= time_offset(Zone, Rule),
date_add(UTCDatetime, SecDiff).
%% local_to_utc(Datetime, TzName) ->
%% {ok, Zone, Rule}= current_as_of_local(Datetime, TzName),
%% SecDiff= time_offset(Zone, Rule),
%% date_subtract(Datetime, SecDiff).
%% zone_convert(Datetime, FromTimeZone, ToTimeZone) ->
%% UTC= local_to_utc(Datetime, FromTimeZone),
%% utc_to_local(UTC, ToTimeZone).
next_timechange(TzName) ->
next_timechange(erlang:universaltime(), TzName).
next_timechange(UTCDatetime, TzName) ->
UTCDatetime, TzName,
not_done.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% DEV API
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
load(Folder) ->
ezic_loader:load(Folder),
ezic_flatten:flatten().
dev_start() ->
ezic:load(filename:join("priv","tzdata")).
test() ->
lists:foreach(
fun(TZ)->
io:format("~s: ~p~n", [TZ, localtime(TZ)])
end,
["Asia/Tokyo", "America/New_York", "America/Los_Angeles", "America/Jamaica", "Australia/Adelaide"]).
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% PRIVATE
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
current_as_of_utc(UTCDatetime, TzName) ->
CZone= ezic_zone:current_as_of_utc(UTCDatetime, TzName),
RuleName= CZone#zone.rule,
Rules= ezic_db:rules(RuleName),
CRule= ezic_rule:current_as_of_utc(UTCDatetime, Rules),
{ok, CZone, CRule}.
%%current_as_of_local(Datetime, TzName) ->
%% not_done.
time_offset(Zone, Rule) ->
OffsetSec= ezic_zone:offset_sec(Zone),
DSTSec= ezic_rule:dst_sec(Rule),
OffsetSec + DSTSec.
date_add(Datetime, SecDiff) ->
?gs2dt(?dt2gs(Datetime) + SecDiff).
%% date_subtract(Datetime, SecDiff) ->
%% ?gs2dt(?dt2gs(Datetime) - SecDiff).