module Util.Time exposing
    ( formatDate
    , formatDateShort
    , formatDateTime
    , formatIsoDateTime
    )

import DateFormat
import Time exposing (Posix, Zone, utc)


dateFormatter : Zone -> Posix -> String
dateFormatter =
    DateFormat.format
        [ DateFormat.dayOfWeekNameAbbreviated
        , DateFormat.text ", "
        , DateFormat.monthNameFull
        , DateFormat.text " "
        , DateFormat.dayOfMonthSuffix
        , DateFormat.text ", "
        , DateFormat.yearNumber
        ]


dateFormatterShort : Zone -> Posix -> String
dateFormatterShort =
    DateFormat.format
        [ DateFormat.yearNumber
        , DateFormat.text "/"
        , DateFormat.monthFixed
        , DateFormat.text "/"
        , DateFormat.dayOfMonthFixed
        ]


timeFormatter : Zone -> Posix -> String
timeFormatter =
    DateFormat.format
        [ DateFormat.hourMilitaryNumber
        , DateFormat.text ":"
        , DateFormat.minuteFixed
        ]


isoDateTimeFormatter : Zone -> Posix -> String
isoDateTimeFormatter =
    DateFormat.format
        [ DateFormat.yearNumber
        , DateFormat.text "-"
        , DateFormat.monthFixed
        , DateFormat.text "-"
        , DateFormat.dayOfMonthFixed
        , DateFormat.text "T"
        , DateFormat.hourMilitaryNumber
        , DateFormat.text ":"
        , DateFormat.minuteFixed
        , DateFormat.text ":"
        , DateFormat.secondFixed
        ]


timeZone : Zone
timeZone =
    utc



{- Format millis into "Wed, 10. Jan 2018, 18:57" -}


formatDateTime : Int -> String
formatDateTime millis =
    formatDate millis ++ ", " ++ formatTime millis


formatIsoDateTime : Int -> String
formatIsoDateTime millis =
    Time.millisToPosix millis
        |> isoDateTimeFormatter timeZone



{- Format millis into "18:57". The current time (not the duration of
   the millis).
-}


formatTime : Int -> String
formatTime millis =
    Time.millisToPosix millis
        |> timeFormatter timeZone



{- Format millis into "Wed, 10. Jan 2018" -}


formatDate : Int -> String
formatDate millis =
    Time.millisToPosix millis
        |> dateFormatter timeZone


formatDateShort : Int -> String
formatDateShort millis =
    Time.millisToPosix millis
        |> dateFormatterShort timeZone