module Text.Haiji.TH
( haiji
, haijiFile
, key
) where
#if MIN_VERSION_base(4,8,0)
#else
import Control.Applicative
#endif
import Control.Monad.Trans.Reader
import Data.Maybe
import Language.Haskell.TH
import Language.Haskell.TH.Quote
import Language.Haskell.TH.Syntax hiding (lift)
import qualified Data.Text as T
import qualified Data.Text.Lazy as LT
import Text.Haiji.Parse
import Text.Haiji.Syntax
import Text.Haiji.Dictionary
import Text.Haiji.Types
haiji :: Environment -> QuasiQuoter
haiji env = QuasiQuoter { quoteExp = haijiExp env
, quotePat = undefined
, quoteType = undefined
, quoteDec = undefined
}
haijiFile :: Quasi q => Environment -> FilePath -> q Exp
haijiFile env file = runQ (runIO $ parseFile file) >>= haijiTemplate env
haijiExp :: Quasi q => Environment -> String -> q Exp
haijiExp env str = runQ (runIO $ parseString str) >>= haijiTemplate env
key :: QuasiQuoter
key = QuasiQuoter { quoteExp = \k -> [e| \v -> singleton v (Key :: Key $(litT . strTyLit $ k)) |]
, quotePat = undefined
, quoteType = undefined
, quoteDec = undefined
}
haijiTemplate :: Quasi q => Environment -> Jinja2 -> q Exp
haijiTemplate env tmpl = runQ [e| Template $(haijiASTs env Nothing (jinja2Child tmpl) (jinja2Base tmpl)) |]
haijiASTs :: Quasi q => Environment -> Maybe [AST 'Fully] -> [AST 'Fully] -> [AST 'Fully] -> q Exp
haijiASTs env parentBlock children asts = runQ [e| LT.concat <$> sequence $(listE $ map (haijiAST env parentBlock children) asts) |]
haijiAST :: Quasi q => Environment -> Maybe [AST 'Fully] -> [AST 'Fully] -> AST 'Fully -> q Exp
haijiAST _env _parentBlock _children (Literal l) =
runQ [e| return $(litE $ stringL $ T.unpack l) |]
haijiAST env _parentBlock _children (Eval x) =
if autoEscape env
then runQ [e| (`escapeBy` htmlEscape) . toLT <$> $(eval x) |]
else runQ [e| (`escapeBy` rawEscape) . toLT <$> $(eval x) |]
haijiAST env parentBlock children (Condition p ts fs) =
runQ [e| do cond <- $(eval p)
if cond
then $(haijiASTs env parentBlock children ts)
else $(maybe [e| return "" |] (haijiASTs env parentBlock children) fs)
|]
haijiAST env parentBlock children (Foreach k xs loopBody elseBody) =
runQ [e| do dicts <- $(eval xs)
p <- ask
let len = length dicts
if 0 < len
then return $ LT.concat
[ runReader $(haijiASTs env parentBlock children loopBody)
(p `merge`
singleton x (Key :: Key $(litT . strTyLit $ show k)) `merge`
singleton (loopVariables len ix) (Key :: Key "loop")
)
| (ix, x) <- zip [0..] dicts
]
else $(maybe [e| return "" |] (haijiASTs env parentBlock children) elseBody)
|]
haijiAST _env _parentBlock _children (Raw raw) = runQ [e| return raw |]
haijiAST _env _parentBlock _children (Base _asts) = undefined
haijiAST env parentBlock children (Block _base name _scoped body) =
case listToMaybe [ b | Block _ n _ b <- children, n == name ] of
Nothing -> haijiASTs env parentBlock children body
Just child -> haijiASTs env (Just body) children child
haijiAST env parentBlock children Super = maybe (error "invalid super()") (haijiASTs env Nothing children) parentBlock
haijiAST _env _parentBlock _children (Comment _) = runQ [e| return "" |]
loopVariables :: Int -> Int -> Dict '["first" :-> Bool, "index" :-> Int, "index0" :-> Int, "last" :-> Bool, "length" :-> Int, "revindex" :-> Int, "revindex0" :-> Int]
loopVariables len ix =
Ext (Value (ix == 0) :: "first" :-> Bool) $
Ext (Value (ix + 1) :: "index" :-> Int ) $
Ext (Value ix :: "index0" :-> Int ) $
Ext (Value (ix == len 1) :: "last" :-> Bool) $
Ext (Value len :: "length" :-> Int ) $
Ext (Value (len ix) :: "revindex" :-> Int ) $
Ext (Value (len ix 1) :: "revindex0" :-> Int ) $
Empty
eval :: Quasi q => Expression -> q Exp
eval (Expression var _) = deref var
deref :: Quasi q => Variable -> q Exp
deref (VariableBase v) =
runQ [e| retrieve <$> ask <*> return (Key :: Key $(litT . strTyLit $ show v)) |]
deref (VariableAttribute v f) =
runQ [e| retrieve <$> $(deref v) <*> return (Key :: Key $(litT . strTyLit $ show f)) |]