module Util.Html exposing (..)

import Html exposing (Attribute)
import Html.Attributes exposing (class)
import Html.Events exposing (on, keyCode)
import Json.Decode as Decode

type KeyCode
    = Up
    | Down
    | Left
    | Right
    | Enter

intToKeyCode: Int -> Maybe KeyCode
intToKeyCode code =
    case code of
        38 -> Just Up
        40 -> Just Down
        39 -> Just Right
        37 -> Just Left
        13 -> Just Enter
        _ -> Nothing

onKeyUp : (Int -> msg) -> Attribute msg
onKeyUp tagger =
  on "keyup" (Decode.map tagger keyCode)


onClickk : msg -> Attribute msg
onClickk msg =
  Html.Events.preventDefaultOn "click" (Decode.map alwaysPreventDefault (Decode.succeed msg))

alwaysPreventDefault : msg -> ( msg, Bool )
alwaysPreventDefault msg =
  ( msg, True )

classActive: Bool -> String -> Attribute msg
classActive active classes =
    class (classes ++ (if active then " active" else ""))