Fixes 4539 : When Wikidata has no description showing instance_of's label as a description (#4799)

* Showing instance_of's name as a description

* Indentation fixed

* DepictsClient Test added

app/src/main/java/fr/free/nrw/commons/explore/depictions/DepictsClient.kt

@@ -1,12 +1,17 @@
 package fr.free.nrw.commons.explore.depictions
 
+import android.annotation.SuppressLint
 import fr.free.nrw.commons.mwapi.Binding
 import fr.free.nrw.commons.mwapi.SparqlResponse
 import fr.free.nrw.commons.upload.depicts.DepictsInterface
 import fr.free.nrw.commons.upload.structure.depictions.DepictedItem
+import fr.free.nrw.commons.upload.structure.depictions.get
+import fr.free.nrw.commons.wikidata.WikidataProperties
 import fr.free.nrw.commons.wikidata.model.DepictSearchItem
 import io.reactivex.Single
+import org.wikipedia.wikidata.DataValue
 import org.wikipedia.wikidata.Entities
+import org.wikipedia.wikidata.Statement_partial
 import java.util.*
 import javax.inject.Inject
 import javax.inject.Singleton
@@ -38,7 +43,50 @@ class DepictsClient @Inject constructor(private val depictsInterface: DepictsInt
         }.mapToDepictions()
     }
 
+    /**
+     * Fetches Entities from ids ex. "Q1233|Q546" and converts them into DepictedItem
+     */
+    @SuppressLint("CheckResult")
     private fun Single<String>.mapToDepictions() =
         flatMap(::getEntities)
-        .map { it.entities().values.map(::DepictedItem) }
+        .map { entities ->
+            entities.entities().values.map { entity ->
+                if (entity.descriptions().byLanguageOrFirstOrEmpty() == "") {
+                    val entities: Entities = getEntities(entity[WikidataProperties.INSTANCE_OF]
+                        .toIds()[0]).blockingGet()
+                    val nameAsDescription = entities.entities().values.first().labels()
+                        .byLanguageOrFirstOrEmpty()
+                    DepictedItem(
+                        entity,
+                        entity.labels().byLanguageOrFirstOrEmpty(),
+                        nameAsDescription
+                    )
+                } else {
+                    DepictedItem(
+                        entity,
+                        entity.labels().byLanguageOrFirstOrEmpty(),
+                        entity.descriptions().byLanguageOrFirstOrEmpty()
+                    )
+                }
+            }
+        }
+
+    /**
+     * Tries to get Entities.Label by default language from the map.
+     * If that returns null, Tries to retrieve first element from the map.
+     * If that still returns null, function returns "".
+     */
+    private fun Map<String, Entities.Label>.byLanguageOrFirstOrEmpty() =
+        let {
+            it[Locale.getDefault().language] ?: it.values.firstOrNull() }?.value() ?: ""
+
+    /**
+     * returns list of id ex. "Q2323" from Statement_partial
+     */
+    private fun List<Statement_partial>?.toIds(): List<String> {
+        return this?.map { it.mainSnak.dataValue }
+            ?.filterIsInstance<DataValue.EntityId>()
+            ?.map { it.value.id }
+            ?: emptyList()
+    }
 }

app/src/main/java/fr/free/nrw/commons/upload/structure/depictions/DepictedItem.kt

@@ -46,7 +46,7 @@ data class DepictedItem constructor(
         place.longDescription
     )
 
-    private constructor(entity: Entities.Entity, name: String, description: String) : this(
+    constructor(entity: Entities.Entity, name: String, description: String) : this(
         name,
         description,
         entity[IMAGE].primaryImageValue?.let {

app/src/test/kotlin/fr/free/nrw/commons/explore/depictions/DepictsClientTest.kt

@@ -7,14 +7,14 @@ import fr.free.nrw.commons.mwapi.Binding
 import fr.free.nrw.commons.mwapi.Result
 import fr.free.nrw.commons.mwapi.SparqlResponse
 import fr.free.nrw.commons.upload.depicts.DepictsInterface
+import fr.free.nrw.commons.upload.structure.depictions.DepictedItem
 import fr.free.nrw.commons.wikidata.model.DepictSearchResponse
 import io.reactivex.Single
 import org.junit.Before
-import org.junit.Ignore
 import org.junit.Test
 import org.mockito.Mock
 import org.mockito.MockitoAnnotations
-import org.wikipedia.wikidata.Entities
+import org.wikipedia.wikidata.*
 
 class DepictsClientTest {
 
@@ -29,7 +29,6 @@ class DepictsClientTest {
     }
 
     @Test
-    @Ignore()
     fun searchForDepictions() {
         val depictSearchResponse = mock<DepictSearchResponse>()
         whenever(depictsInterface.searchForDepicts("query", "1", "en", "en", "0"))
@@ -52,7 +51,7 @@ class DepictsClientTest {
     }
 
     @Test
-    fun toDepictions() {
+    fun `Test toDepictions when description is empty`() {
         val sparqlResponse = mock<SparqlResponse>()
         val result = mock<Result>()
         whenever(sparqlResponse.results).thenReturn(result)
@@ -62,10 +61,51 @@ class DepictsClientTest {
         whenever(binding1.id).thenReturn("1")
         whenever(binding2.id).thenReturn("2")
         val entities = mock<Entities>()
+        val entity = mock<Entities.Entity>()
+        val statementPartial = mock<Statement_partial>()
         whenever(depictsInterface.getEntities("1|2")).thenReturn(Single.just(entities))
-        whenever(entities.entities()).thenReturn(emptyMap())
+        whenever(entities.entities()).thenReturn(mapOf("en" to entity))
+        whenever(entity.statements).thenReturn(mapOf("P31" to listOf(statementPartial)))
+        whenever(statementPartial.mainSnak).thenReturn(
+            Snak_partial("test", "P31",
+                DataValue.EntityId(
+                    WikiBaseEntityValue("wikibase-entityid", "Q10", 10L)
+                )
+            )
+        )
+        whenever(depictsInterface.getEntities("Q10")).thenReturn(Single.just(entities))
+        whenever(entity.id()).thenReturn("Q10")
         depictsClient.toDepictions(Single.just(sparqlResponse))
             .test()
-            .assertValue(emptyList())
+            .assertValue(listOf(
+                DepictedItem("", "", null,
+                    listOf("Q10"), emptyList(), false, "Q10")
+            ))
+    }
+
+    @Test
+    fun `Test toDepictions when description is not empty`() {
+        val sparqlResponse = mock<SparqlResponse>()
+        val result = mock<Result>()
+        whenever(sparqlResponse.results).thenReturn(result)
+        val binding1 = mock<Binding>()
+        val binding2 = mock<Binding>()
+        whenever(result.bindings).thenReturn(listOf(binding1, binding2))
+        whenever(binding1.id).thenReturn("1")
+        whenever(binding2.id).thenReturn("2")
+        val entities = mock<Entities>()
+        val entity = mock<Entities.Entity>()
+        whenever(depictsInterface.getEntities("1|2")).thenReturn(Single.just(entities))
+        whenever(entities.entities()).thenReturn(mapOf("en" to entity))
+        whenever(entity.descriptions()).thenReturn(mapOf("en" to
+                Entities.Label("en", "Test description")
+        ))
+        whenever(entity.id()).thenReturn("Q10")
+        depictsClient.toDepictions(Single.just(sparqlResponse))
+            .test()
+            .assertValue(listOf(
+                DepictedItem("", "", null, listOf("Q10"),
+                    emptyList(), false, "Q10")
+            ))
     }
 }

data-client/src/main/java/org/wikipedia/wikidata/Entities.java

@@ -78,6 +78,11 @@ public class Entities extends MwResponse implements PostProcessingTypeAdapter.Po
         @Nullable private String language;
         @Nullable private String value;
 
+        public Label(@Nullable final String language, @Nullable final String value) {
+            this.language = language;
+            this.value = value;
+        }
+
         @NonNull public String language() {
             return StringUtils.defaultString(language);
         }