Add compatibility layer between RSAComb and PAGOdA query answers

1 files changed, 146 insertions, 0 deletions

diff --git a/src/main/scala/uk/ac/ox/cs/acqua/implicits/RSACombAnswerTuples.scala b/src/main/scala/uk/ac/ox/cs/acqua/implicits/RSACombAnswerTuples.scala
new file mode 100644
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--- /dev/null
+++ b/src/main/scala/uk/ac/ox/cs/acqua/implicits/RSACombAnswerTuples.scala
@@ -0,0 +1,146 @@
+/*
+ * Copyright 2021,2022 KRR Oxford
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package uk.ac.ox.cs.acqua.implicits
+
+import uk.ac.ox.cs.JRDFox.model.{
+  BlankNode => OldBlankNode,
+  Datatype => OldDatatype,
+  Individual => OldIndividual,
+  Literal => OldLiteral,
+}
+import tech.oxfordsemantic.jrdfox.logic.Datatype
+import tech.oxfordsemantic.jrdfox.logic.expression.{
+  BlankNode,
+  IRI,
+  Literal,
+  Resource
+}
+import uk.ac.ox.cs.pagoda.query.{AnswerTuple,AnswerTuples}
+import uk.ac.ox.cs.rsacomb.sparql.ConjunctiveQueryAnswers
+
+/** Implicit wrapper around [[uk.ac.ox.cs.rsacomb.sparql.ConjunctiveQueryAnswers]]
+  *
+  * It implicitly converts a [[uk.ac.ox.cs.rsacomb.sparql.ConjunctiveQueryAnswers]]
+  * into a [[uk.ac.ox.cs.pagoda.query.AnswerTuples]] to maintain
+  * compatibility betweren RSAComb and PAGOdA.
+  */
+object RSACombAnswerTuples {
+
+  implicit class RSACombAnswerTuples(
+      val answers: ConjunctiveQueryAnswers
+    ) extends AnswerTuples {
+
+    /* TODO: this might not be the best choice, since the internal
+     * iterator in a collection is a single traverse iterator.
+     * We might be messing with internal state.
+     */
+    private var iter = answers.answers.iterator
+
+    /** Reset the iterator over the answers.
+      *
+      * @note this operation is currently not supported.
+      */
+    def reset(): Unit = ???
+
+    /** True if the iterator can provide more items. */
+    def isValid: Boolean = iter.hasNext
+
+    /** Get arity of answer variables. */
+    def getArity: Int = answers.query.answer.length
+
+    /** Get array of answer variable names */
+    def getAnswerVariables: Array[String] =
+      answers.query.answer.map(_.getName).toArray
+
+    /** Advance iterator state */
+    def moveNext(): Unit = { }
+
+    /** Get next [[uk.ac.ox.cs.pagoda.query.AnswerTuple]] from the iterator */
+    def getTuple: AnswerTuple = iter.next()
+
+    /** Return true if the input tuple is part of this collection.
+      *
+      * @param tuple the answer to be checked.
+      */
+    def contains(tuple: AnswerTuple): Boolean =
+      answers.contains(tuple)
+
+    /** Skip one item in the iterator.
+      *
+      * @note that the semantic of this method is not clear to the
+      * author and the description is just an assumption.
+      */
+    def remove(): Unit = iter.next()
+  }
+
+  /** Implicit convertion from RSAComb-style answers to [[uk.ac.ox.cs.pagoda.query.AnswerTuple]] */
+  private implicit def asAnswerTuple(
+    answer: (Long,Seq[Resource])
+  ): AnswerTuple = new AnswerTuple(answer._2.map(res =>
+    res match {
+      case r: IRI => OldIndividual.create(r.getIRI)
+      case r: BlankNode => OldBlankNode.create(r.getID)
+      case r: Literal => OldLiteral.create(r.getLexicalForm,r.getDatatype)
+    }
+  ).toArray)
+
+  /** Implicit convertion from [[tech.oxfordsemantic.jrdfox.logic.Datatype]] to [[uk.ac.ox.cs.JRDFox.model.Datatype]]
+    *
+    * @note this might not be 100% accurate since the two interfaces are
+    * slightly different.
+    */
+  private implicit def asOldDatatype(
+    datatype: Datatype
+  ): OldDatatype = datatype match {
+    case Datatype.BLANK_NODE => OldDatatype.BLANK_NODE
+    case Datatype.IRI_REFERENCE => OldDatatype.IRI_REFERENCE
+    case Datatype.RDF_PLAIN_LITERAL => OldDatatype.RDF_PLAIN_LITERAL
+    case Datatype.RDFS_LITERAL => OldDatatype.RDFS_LITERAL
+    case Datatype.XSD_ANY_URI => OldDatatype.XSD_ANY_URI
+    case Datatype.XSD_BOOLEAN => OldDatatype.XSD_BOOLEAN
+    case Datatype.XSD_BYTE => OldDatatype.XSD_BYTE
+    case Datatype.XSD_DATE => OldDatatype.XSD_DATE
+    case Datatype.XSD_DATE_TIME => OldDatatype.XSD_DATE_TIME
+    case Datatype.XSD_DATE_TIME_STAMP => OldDatatype.XSD_DATE_TIME_STAMP
+    case Datatype.XSD_DECIMAL => OldDatatype.XSD_DECIMAL
+    case Datatype.XSD_DOUBLE => OldDatatype.XSD_DOUBLE
+    case Datatype.XSD_DURATION => OldDatatype.XSD_DURATION
+    case Datatype.XSD_FLOAT => OldDatatype.XSD_FLOAT
+    case Datatype.XSD_G_DAY => OldDatatype.XSD_G_DAY
+    case Datatype.XSD_G_MONTH => OldDatatype.XSD_G_MONTH
+    case Datatype.XSD_G_MONTH_DAY => OldDatatype.XSD_G_MONTH_DAY
+    case Datatype.XSD_G_YEAR => OldDatatype.XSD_G_YEAR
+    case Datatype.XSD_G_YEAR_MONTH => OldDatatype.XSD_G_YEAR_MONTH
+    case Datatype.XSD_INT => OldDatatype.XSD_INT
+    case Datatype.XSD_INTEGER => OldDatatype.XSD_INTEGER
+    case Datatype.XSD_LONG => OldDatatype.XSD_LONG
+    case Datatype.XSD_NEGATIVE_INTEGER => OldDatatype.XSD_NEGATIVE_INTEGER
+    case Datatype.XSD_NON_NEGATIVE_INTEGER => OldDatatype.XSD_NON_NEGATIVE_INTEGER
+    case Datatype.XSD_NON_POSITIVE_INTEGER => OldDatatype.XSD_NON_POSITIVE_INTEGER
+    case Datatype.XSD_POSITIVE_INTEGER => OldDatatype.XSD_POSITIVE_INTEGER
+    case Datatype.XSD_SHORT => OldDatatype.XSD_SHORT
+    case Datatype.XSD_STRING => OldDatatype.XSD_STRING
+    case Datatype.XSD_TIME => OldDatatype.XSD_TIME
+    case Datatype.XSD_UNSIGNED_BYTE => OldDatatype.XSD_UNSIGNED_BYTE
+    case Datatype.XSD_UNSIGNED_INT => OldDatatype.XSD_UNSIGNED_INT
+    case Datatype.XSD_UNSIGNED_LONG => OldDatatype.XSD_UNSIGNED_LONG
+    case Datatype.XSD_UNSIGNED_SHORT => OldDatatype.XSD_UNSIGNED_SHORT
+    case Datatype.XSD_DAY_TIME_DURATION => OldDatatype.XSD_DURATION
+    case Datatype.XSD_YEAR_MONTH_DURATION => OldDatatype.XSD_DURATION
+    case Datatype.INVALID_DATATYPE => OldDatatype.XSD_ANY_URI
+  }
+}