{-# LANGUAGE DeriveDataTypeable #-}

{- |

Module : ./RDF/AS.hs

Copyright : (c) Felix Gabriel Mance, Francisc-Nicolae Bungiu

License : GPLv2 or higher, see LICENSE.txt

Maintainer : Christian.Maeder@dfki.de

Stability : provisional

Portability : portable

RDF abstract syntax

References:

<http://www.w3.org/TeamSubmission/turtle/>

<http://www.informatik.uni-bremen.de/~till/papers/ontotrans.pdf>

<http://www.w3.org/TR/rdf-concepts/#section-Graph-syntax>

-}

module RDF.AS where

import Common.Id

import Common.IRI

import OWL2.AS

import Data.Data

import Data.List

import qualified Data.Map as Map

-- * RDF Turtle Document

type RDFPrefixMap = Map.Map String IRI

data TurtleDocument = TurtleDocument

{ documentName :: IRI

, prefixMap :: RDFPrefixMap

, statements :: [Statement] }

deriving (Show, Eq, Ord, Typeable, Data)

emptyTurtleDocument :: TurtleDocument

emptyTurtleDocument = TurtleDocument nullIRI Map.empty []

data Statement = Statement Triples | PrefixStatement Prefix | BaseStatement Base

deriving (Show, Eq, Ord, Typeable, Data)

data Prefix = PrefixR String IRI

deriving (Show, Eq, Ord, Typeable, Data)

data Base = Base IRI

deriving (Show, Eq, Ord, Typeable, Data)

data Triples = Triples Subject [PredicateObjectList]

deriving (Show, Eq, Ord, Typeable, Data)

data Subject =

Subject IRI

| SubjectList [PredicateObjectList]

| SubjectCollection [Object]

deriving (Show, Eq, Ord, Typeable, Data)

data Predicate = Predicate IRI

deriving (Show, Eq, Ord, Typeable, Data)

data Object = Object Subject

| ObjectLiteral RDFLiteral

deriving (Show, Eq, Ord, Typeable, Data)

data PredicateObjectList = PredicateObjectList Predicate [Object]

deriving (Show, Eq, Ord, Typeable, Data)

data RDFLiteral = RDFLiteral Bool LexicalForm TypedOrUntyped

| RDFNumberLit FloatLit

deriving (Show, Eq, Ord, Typeable, Data)

-- * Datatypes for Hets manipulation

data Term =

SubjectTerm IRI

| PredicateTerm IRI

| ObjectTerm (Either IRI RDFLiteral)

deriving (Show, Eq, Ord, Typeable, Data)

data Axiom = Axiom Term Term Term

deriving (Show, Eq, Ord, Typeable, Data)

data RDFEntityType = SubjectEntity | PredicateEntity | ObjectEntity

deriving (Show, Eq, Ord, Bounded, Enum, Typeable, Data)

-- | entities used for morphisms

data RDFEntity = RDFEntity RDFEntityType Term

deriving (Show, Eq, Ord, Typeable, Data)

rdfEntityTypes :: [RDFEntityType]

rdfEntityTypes = [minBound .. maxBound]

instance GetRange TurtleDocument where

instance GetRange RDFEntity where

instance GetRange Axiom where

-- | useful functions

extractTripleStatements :: [Statement] -> [Triples]

extractTripleStatements ls = case ls of

[] -> []

h : t -> case h of

Statement triple -> triple : extractTripleStatements t

_ -> extractTripleStatements t

triplesOfDocument :: TurtleDocument -> [Triples]

triplesOfDocument doc = extractTripleStatements $ statements doc

rdfFirst :: IRI

rdfFirst = nullIRI { prefixName = "rdf"

, iriPath = stringToId "first"

, isAbbrev = True }

rdfRest :: IRI

rdfRest = nullIRI { prefixName = "rdf"

, iriPath = stringToId "rest"

, isAbbrev = True }

rdfNil :: IRI

rdfNil = nullIRI { prefixName = "rdf"

, iriPath = stringToId "nil"

, isAbbrev = True }

isAbsoluteIRI :: IRI -> Bool

isAbsoluteIRI i = hasFullIRI i && isPrefixOf "//" (show $ iriPath i)