module Text.Hamlet.Quasi
( hamlet
, xhamlet
, hamletDebug
, hamletWithSettings
, hamletWithSettings'
, hamletFile
, xhamletFile
, hamletFileWithSettings
, HamletValue (..)
, varName
, Html
, Hamlet
, readUtf8File
) where
import Text.Shakespeare
import Text.Hamlet.Parse
import Language.Haskell.TH.Syntax
import Language.Haskell.TH.Quote
import Data.Char (isUpper, isDigit)
import Data.Monoid (Monoid (..))
import Data.Maybe (fromMaybe)
import qualified Data.Text.Lazy as TL
import qualified Data.Text.Lazy.IO as TIO
import qualified System.IO as SIO
import Text.Blaze (Html, preEscapedString, string, toHtml)
readUtf8File :: FilePath -> IO TL.Text
readUtf8File fp = do
h <- SIO.openFile fp SIO.ReadMode
SIO.hSetEncoding h SIO.utf8_bom
TIO.hGetContents h
docsToExp :: Scope -> [Doc] -> Q Exp
docsToExp scope docs = do
exps <- mapM (docToExp scope) docs
case exps of
[] -> [|return ()|]
[x] -> return x
_ -> return $ DoE $ map NoBindS exps
docToExp :: Scope -> Doc -> Q Exp
docToExp scope (DocForall list ident@(Ident name) inside) = do
let list' = derefToExp scope list
name' <- newName name
let scope' = (ident, VarE name') : scope
mh <- [|mapM_|]
inside' <- docsToExp scope' inside
let lam = LamE [VarP name'] inside'
return $ mh `AppE` lam `AppE` list'
docToExp scope (DocMaybe val ident@(Ident name) inside mno) = do
let val' = derefToExp scope val
name' <- newName name
let scope' = (ident, VarE name') : scope
inside' <- docsToExp scope' inside
let inside'' = LamE [VarP name'] inside'
ninside' <- case mno of
Nothing -> [|Nothing|]
Just no -> do
no' <- docsToExp scope no
j <- [|Just|]
return $ j `AppE` no'
mh <- [|maybeH|]
return $ mh `AppE` val' `AppE` inside'' `AppE` ninside'
docToExp scope (DocCond conds final) = do
conds' <- mapM go conds
final' <- case final of
Nothing -> [|Nothing|]
Just f -> do
f' <- docsToExp scope f
j <- [|Just|]
return $ j `AppE` f'
ch <- [|condH|]
return $ ch `AppE` ListE conds' `AppE` final'
where
go :: (Deref, [Doc]) -> Q Exp
go (d, docs) = do
let d' = derefToExp scope d
docs' <- docsToExp scope docs
return $ TupE [d', docs']
docToExp v (DocContent c) = contentToExp v c
contentToExp :: Scope -> Content -> Q Exp
contentToExp _ (ContentRaw s) = do
os <- [|htmlToHamletMonad . preEscapedString|]
let s' = LitE $ StringL s
return $ os `AppE` s'
contentToExp scope (ContentVar d) = do
str <- [|htmlToHamletMonad . toHtml|]
return $ str `AppE` derefToExp scope d
contentToExp scope (ContentUrl hasParams d) = do
ou <- if hasParams
then [|\(u, p) -> urlToHamletMonad u p|]
else [|\u -> urlToHamletMonad u []|]
let d' = derefToExp scope d
return $ ou `AppE` d'
contentToExp scope (ContentEmbed d) = do
let d' = derefToExp scope d
fhv <- [|fromHamletValue|]
return $ fhv `AppE` d'
hamlet :: QuasiQuoter
hamlet = hamletWithSettings defaultHamletSettings
hamletDebug :: QuasiQuoter
hamletDebug = hamletWithSettings debugHamletSettings
xhamlet :: QuasiQuoter
xhamlet = hamletWithSettings xhtmlHamletSettings
hamletWithSettings :: HamletSettings -> QuasiQuoter
hamletWithSettings set =
QuasiQuoter
{ quoteExp = hamletFromString set
}
hamletWithSettings' :: HamletSettings -> QuasiQuoter
hamletWithSettings' set =
QuasiQuoter
{ quoteExp = \s -> do
x <- hamletFromString set s
id' <- [|(\y _ -> y) :: String -> [(String, String)] -> String|]
return $ x `AppE` id'
}
hamletFromString :: HamletSettings -> String -> Q Exp
hamletFromString set s = do
case parseDoc set s of
Error s' -> error s'
Ok d -> do
thv <- [|toHamletValue|]
exp' <- docsToExp [] d
return $ thv `AppE` exp'
hamletFileWithSettings :: HamletSettings -> FilePath -> Q Exp
hamletFileWithSettings set fp = do
contents <- fmap TL.unpack $ qRunIO $ readUtf8File fp
hamletFromString set contents
hamletFile :: FilePath -> Q Exp
hamletFile = hamletFileWithSettings defaultHamletSettings
xhamletFile :: FilePath -> Q Exp
xhamletFile = hamletFileWithSettings xhtmlHamletSettings
varName :: Scope -> String -> Exp
varName _ "" = error "Illegal empty varName"
varName scope v@(_:_) = fromMaybe (strToExp v) $ lookup (Ident v) scope
strToExp :: String -> Exp
strToExp s@(c:_)
| all isDigit s = LitE $ IntegerL $ read s
| isUpper c = ConE $ mkName s
| otherwise = VarE $ mkName s
strToExp "" = error "strToExp on empty string"
condH :: Monad m => [(Bool, m ())] -> Maybe (m ()) -> m ()
condH [] Nothing = return ()
condH [] (Just x) = x
condH ((True, y):_) _ = y
condH ((False, _):rest) z = condH rest z
maybeH :: Monad m => Maybe v -> (v -> m ()) -> Maybe (m ()) -> m ()
maybeH Nothing _ Nothing = return ()
maybeH Nothing _ (Just x) = x
maybeH (Just v) f _ = f v
type Hamlet url = (url -> [(String, String)] -> String) -> Html
class Monad (HamletMonad a) => HamletValue a where
data HamletMonad a :: * -> *
type HamletUrl a
toHamletValue :: HamletMonad a () -> a
htmlToHamletMonad :: Html -> HamletMonad a ()
urlToHamletMonad :: HamletUrl a -> [(String, String)] -> HamletMonad a ()
fromHamletValue :: a -> HamletMonad a ()
type Render url = url -> [(String, String)] -> String
instance HamletValue (Hamlet url) where
newtype HamletMonad (Hamlet url) a =
HMonad { runHMonad :: Render url -> (Html, a) }
type HamletUrl (Hamlet url) = url
toHamletValue = fmap fst . runHMonad
htmlToHamletMonad x = HMonad $ const (x, ())
urlToHamletMonad url pairs = HMonad $ \r ->
(string $ r url pairs, ())
fromHamletValue f = HMonad $ \r -> (f r, ())
instance Monad (HamletMonad (Hamlet url)) where
return x = HMonad $ const (mempty, x)
(HMonad f) >>= g = HMonad $ \render ->
let (html1, x) = f render
(html2, y) = runHMonad (g x) render
in (html1 `mappend` html2, y)
data NoConstructor
instance HamletValue Html where
newtype HamletMonad Html a = HtmlMonad { runHtmlMonad :: (Html, a) }
type HamletUrl Html = NoConstructor
toHamletValue = fst . runHtmlMonad
htmlToHamletMonad x = HtmlMonad (x, ())
urlToHamletMonad = error "urlToHamletMonad on NoConstructor"
fromHamletValue h = HtmlMonad (h, ())
instance Monad (HamletMonad Html) where
return x = HtmlMonad (mempty, x)
HtmlMonad (html1, x) >>= g = HtmlMonad $
let HtmlMonad (html2, y) = g x
in (html1 `mappend` html2, y)