elm/exercises/gigasecond/Gigasecond.example
2016-08-28 21:46:23 -06:00

121 lines
2.2 KiB
Text

module Gigasecond exposing (add)
import Date
import Time
import String
add : String -> Result String String
add x =
x
|> Date.fromString
|> Result.map (add' gigasecond)
|> Result.map format
add' : Time.Time -> Date.Date -> Date.Date
add' t d =
d
|> Date.toTime
|> flip (+) t
|> Date.fromTime
gigasecond : Time.Time
gigasecond =
10 ^ 12
format : Date.Date -> String
format date =
let
date =
toGMT date
in
--toString date
[ Date.year date
|> toString
, "-"
, Date.month date
|> monthToInt
|> Maybe.withDefault 1
|> toString
|> String.pad 2 '0'
, "-"
, Date.day date
|> toString
|> String.pad 2 '0'
, "T"
, Date.hour date
|> toString
|> String.pad 2 '0'
, ":"
, Date.minute date
|> toString
|> String.pad 2 '0'
, ":"
, Date.second date
|> toString
|> String.pad 2 '0'
]
|> String.concat
monthToInt : Date.Month -> Maybe Int
monthToInt n =
case n of
Date.Jan ->
Just 1
Date.Feb ->
Just 2
Date.Mar ->
Just 3
Date.Apr ->
Just 4
Date.May ->
Just 5
Date.Jun ->
Just 6
Date.Jul ->
Just 7
Date.Aug ->
Just 8
Date.Sep ->
Just 9
Date.Oct ->
Just 10
Date.Nov ->
Just 11
Date.Dec ->
Just 12
toGMT : Date.Date -> Date.Date
toGMT date =
let
tzOffset =
date
|> toString
|> String.split " "
|> List.drop 5
|> List.head
|> Maybe.withDefault "GMT-0000"
|> String.dropLeft 3
|> String.toInt
|> Result.withDefault 0
|> flip (//) 100
|> toFloat
|> (*) -Time.hour
in
add' tzOffset date