Events.elm

module Events (onChange, onEnter, onSubmitPreventDefault) where

{-| Extensions to the Html.Events library.

@docs onEnter
-}

import Html exposing (Attribute)
import Html.Events exposing (..)
import Json.Decode as Json
import Signal exposing (..)


onEnter : Address a -> a -> Attribute
onEnter address value =
  on
    "keydown"
    (Json.customDecoder keyCode is13)
    (\_ -> Signal.message address value)


is13 : Int -> Result String ()
is13 code =
  if code == 13 then
    Ok ()
  else
    Err "not the right key code"


onChange : Address a -> (String -> a) -> Html.Attribute
onChange address f =
  on "input" targetValue (message (forwardTo address f))


onSubmitPreventDefault address message =
  onWithOptions
    "submit"
    { defaultOptions | preventDefault = True }
    Json.value
    (\_ -> Signal.message address message)