module Text.XHtml.Strict.Formlets ( input, textarea, password, file
, hidden, inputInteger, radio, enumRadio
, selectRaw, select
, XHtmlForm
, module Text.Formlets
) where
import Text.Formlets
import qualified Text.XHtml.Strict as X
import Text.XHtml.Strict ((!), (+++), (<<))
import Control.Applicative
import Control.Applicative.Error
import Data.List (elemIndex)
type XHtmlForm m a = Form X.Html m a
instance Plus X.Html where
zero = X.noHtml
plus = (+++)
-- | An input field with an optional value
input :: Monad m => Maybe String -> XHtmlForm m String
input = input' (\n v -> X.textfield n ! [X.value v])
textarea :: Monad m => Maybe String -> XHtmlForm m String
textarea = input' (\n v -> X.textarea (X.toHtml v) ! [X.name n])
-- | A password field with an optional value
password :: Monad m => Maybe String -> XHtmlForm m String
password = input' (\n v -> X.password n ! [X.value v])
-- | A hidden input field
hidden :: Monad m => Maybe String -> XHtmlForm m String
hidden = input' X.hidden
-- | A validated integer component
inputInteger :: Monad m => Maybe Integer -> XHtmlForm m Integer
inputInteger x = input (fmap show x) `check` asInteger
file :: Monad m => XHtmlForm m File
file = inputFile X.afile
-- | A radio choice
radio :: Monad m => [(String, String)] -> Maybe String -> XHtmlForm m String
radio choices = input' mkRadios -- todo: validate that the result was in the choices
where radio n v i = X.input ! [X.thetype "radio", X.name n, X.identifier i, X.theclass "radio", X.value v]
mkRadios name selected = X.concatHtml $ map (mkRadio name selected) (zip choices [1..])
mkRadio name selected ((value, label), idx) = (radio name value ident) ! attrs
+++ X.label (X.toHtml label) ! [X.thefor ident, X.theclass "radio"]
where attrs | selected == value = [X.checked]
| otherwise = []
ident = name ++ "_" ++ show idx
-- | An radio choice for Enums
enumRadio :: (Monad m, Enum a) => [(a, String)] -> Maybe a -> XHtmlForm m a
enumRadio values defaultValue = radio (map toS values) (fmap (show . fromEnum) defaultValue)
`check` convert `check` tryToEnum
where toS = fmapFst (show . fromEnum)
convert v = maybeRead' v "Conversion error"
selectRaw :: Monad m => [(String, String)] -> Maybe String -> XHtmlForm m String
selectRaw choices = input' mkChoices -- todo: validate that the result was in the choices
where mkChoices name selected = X.select ! [X.name name] $ X.concatHtml $ map (mkChoice selected) choices
mkChoice selected (value, label) = X.option ! (attrs ++ [X.value value]) << label
where attrs | selected == value = [X.selected]
| otherwise = []
-- | A drop-down for anything that is an instance of Eq
select :: (Eq a, Monad m) => [(a, String)] -> Maybe a -> XHtmlForm m a
select ls v = selectRaw (map f $ zip [0..] ls) selected `check` asInt `check` convert
where selected = show <$> (v >>= flip elemIndex (map fst ls))
f (idx, (_,l)) = (show idx, l)
convert i | i >= length ls || i < 0 = Failure ["Out of bounds"]
| otherwise = Success $ fst $ ls !! i
asInt s = maybeRead' s (s ++ " is not a valid int")