--[[
Illarion Server

This program is free software: you can redistribute it and/or modify it under
the terms of the GNU Affero General Public License as published by the Free
Software Foundation, either version 3 of the License, or (at your option) any
later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
PARTICULAR PURPOSE.  See the GNU Affero General Public License for more
details.

You should have received a copy of the GNU Affero General Public License along
with this program.  If not, see <http://www.gnu.org/licenses/>.
]]
local M = {}

M.daysPerMonth = {31,28,31,30,31,30,31,31,30,31,30,31}
local TIMEZONE=-5

--[[
    Converts a unix timestamp into the RL date
    @param timestamp - unix timestamp
    @return year - the year of the given timestamp
    @return month - the month of the given timestamp
    @return day - the day of the given timestamp
    @return hour - the hour of the given timestamp
    @return minute - the minute of the given timestamp
    @return second - the second of the given timestamp
]]
function M.getRLDateFromUnixTimestamp(timestamp)
    local year=math.floor(1970+ timestamp /31556926)
    local ds=((1970+timestamp/31556926)-year)*31556926
    local month=math.floor(ds/2629743)+1
    local day=math.floor(((ds/2629743+1)-month)*M.daysPerMonth[month])+2
    local DST=0;

    if(month==3)then
        if(day>=14)then
            DST=1 else DST=0
        end
    elseif(month==11)then
        if(day>=7)then
            DST=0 else DST=1
        end
    end
    local hour=math.floor(math.fmod(timestamp,60*60*24)/3600) + 5 + (TIMEZONE) + (DST)
    local minute= math.floor(math.fmod(timestamp,60*60*24)/60 - 60*(hour-DST))
    local second= math.floor(math.fmod(math.fmod(timestamp,60*60*24),60))
    return year, month, day, hour, minute, second;
end

return M