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package rsacomb
import java.io.File
import java.util.HashMap
import java.util.stream.{Stream,Collectors}
import org.semanticweb.owlapi.apibinding.OWLManager
import org.semanticweb.owlapi.model.{AxiomType, ClassExpressionType, OWLObjectSomeValuesFrom}
import org.semanticweb.owlapi.model.{OWLAxiom, OWLSubClassOfAxiom, OWLEquivalentClassesAxiom}
import org.semanticweb.owlapi.model.OWLClassExpression
import org.semanticweb.owlapi.model.OWLOntology
import org.semanticweb.owlapi.model.OWLOntologyManager
import org.semanticweb.owlapi.model.parameters.Imports
import tech.oxfordsemantic.jrdfox.Prefixes
import tech.oxfordsemantic.jrdfox.client.{ConnectionFactory, ServerConnection, DataStoreConnection}
import tech.oxfordsemantic.jrdfox.client.UpdateType
import tech.oxfordsemantic.jrdfox.logic.{Rule, Atom, Literal, Predicate, Term, Variable}
import tech.oxfordsemantic.jrdfox.logic.{Bind, BuiltinFunctionCall}
import scala.collection.JavaConverters._
import rsacomb.SkolemStrategy
class RSA(ontology : OWLOntology) {
/* Alternative constructor(s) */
def this(file : File) = this(RSA.loadOntology(file))
def getOntology : OWLOntology = ontology
} // class RSA
object RSA {
def loadOntology( onto : File ) : OWLOntology = {
/* Retrieve ontology manager */
val manager : OWLOntologyManager = OWLManager.createOWLOntologyManager()
/* Retrieve ontology */
manager.loadOntologyFromOntologyDocument(onto)
}
def isRSA( onto : OWLOntology ) : Boolean = {
/* TODO: Steps for RSA check
* 1) convert ontology axioms into LP rules
* 2) call RDFox on the onto and compute materialization
* 3) build graph from E(x,y) facts
* 4) check if the graph is tree-like
*/
/* Ontology axiom convertion into LP rules */
for {
axiom <- onto.tboxAxioms(Imports.EXCLUDED).collect(Collectors.toList()).asScala
visitor = new RDFoxAxiomConverter(Variable.create("x"), SkolemStrategy.Constant(axiom.toString))
rule <- axiom.accept(visitor)
} yield println(rule)
/* Return true for now... */
true
}
} // object RSA
object RSAComb {
val help : String = """
rsacomb - combined approach for CQ answering for RSA ontologies.
USAGE
rsacomb <path/to/ontology.owl> <path/to/query.sparql>
where
the ontology is expected to be an OWL file and the (single)
query a SPARQL query file.
"""
def main( args : Array[String] ) : Unit = {
/* Simple arguments handling
*
* TODO: use something better later on
*/
if (args.length < 2) {
println(help)
return ()
}
val ontologyPath = new File(args(0))
val queryPath = new File(args(1))
if (!ontologyPath.isFile || !queryPath.isFile) {
println("The provided arguments are not regular files.\n\n")
println(help)
return ()
}
/* Create RSA object from generic OWLOntology
*
* TODO: It might be required to check if the ontology in input is
* Horn-ALCHOIQ. At the moment we are assuming this is always the
* case.
*/
val rsa = new RSA(ontologyPath)
RSA.isRSA(rsa.getOntology)
/* Build canonical model */
//val tboxCanon = rsa.canonicalModel()
/* Load query */
//val query = ...
/* Compute the filtering program from the given query */
//val tboxFilter = rsa.filteringProgram(query)
/* ... */
/* DEBUG ONLY */
println("Ok!")
}
}
/* Notes:
*
* To establish a connection with a local RDFox instance, do the
* following:
*
* ```
* val serverConnection : ServerConnection = ConnectionFactory.newServerConnection("rdfox:local", "", "")
* serverConnection.createDataStore("test","seq",new HashMap())
* val dataStoreConnection : DataStoreConnection = serverConnection.newDataStoreConnection("test")
* dataStoreConnection.importData(
* UpdateType.ADDITION,
* Prefixes.s_emptyPrefixes,
* new File("./path/to/file")
* )
* ```
*/
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