From 34568ca9b149e6bc490f4661de58bbfa69d7a6b6 Mon Sep 17 00:00:00 2001
From: Antonin Delpeuch <antonin@delpeuch.eu>
Date: Thu, 19 Oct 2017 18:15:22 +0100
Subject: [PATCH] Initial support for creation of new items in Wikidata

---
 .../scripts/dialogs/perform-edits-dialog.html |   4 -
 .../scripts/dialogs/perform-edits-dialog.js   |   6 +-
 .../wikidata/editing/CellCoordinates.java     |  33 ++++++
 .../CellCoordinatesKeyDeserializer.java       |  18 +++
 .../wikidata/editing/NewItemLibrary.java      | 104 ++++++++++++++++++
 .../exporters/QuickStatementsExporter.java    |   2 +-
 .../PerformWikibaseEditsOperation.java        | 101 +++++++++++------
 .../wikidata/schema/ExpressionContext.java    |  14 ++-
 .../wikidata/schema/ItemUpdate.java           |  53 +++++++++
 .../wikidata/schema/NewEntityIdValue.java     |  90 +++++++++++++++
 .../wikidata/schema/WbItemVariable.java       |   3 +-
 .../wikidata/schema/WbNameDescExpr.java       |   2 +-
 .../wikidata/schema/WikibaseSchema.java       |   2 +-
 13 files changed, 388 insertions(+), 44 deletions(-)
 create mode 100644 extensions/wikidata/src/org/openrefine/wikidata/editing/CellCoordinates.java
 create mode 100644 extensions/wikidata/src/org/openrefine/wikidata/editing/CellCoordinatesKeyDeserializer.java
 create mode 100644 extensions/wikidata/src/org/openrefine/wikidata/editing/NewItemLibrary.java
 create mode 100644 extensions/wikidata/src/org/openrefine/wikidata/schema/NewEntityIdValue.java

diff --git a/extensions/wikidata/module/scripts/dialogs/perform-edits-dialog.html b/extensions/wikidata/module/scripts/dialogs/perform-edits-dialog.html
index 3adb0f596..82414b252 100644
--- a/extensions/wikidata/module/scripts/dialogs/perform-edits-dialog.html
+++ b/extensions/wikidata/module/scripts/dialogs/perform-edits-dialog.html
@@ -8,10 +8,6 @@
     </p>
     <div class="wikibase-perform-edits-area">
         <p>You are logged in as <span bind="loggedInUsername"></span>.</p>
-        <form bind="performEditsForm">
-            <input type="hidden" name="strategy" value="SNAK_QUALIFIERS" />
-            <input type="hidden" name="action" value="MERGE" />
-        </form>
         <div class="wikibase-login-buttons">
             <button class="button cancel-button" bind="cancelButton">Cancel</button>
             <button class="button button-primary" bind="performEditsButton">Perform edits</button>
diff --git a/extensions/wikidata/module/scripts/dialogs/perform-edits-dialog.js b/extensions/wikidata/module/scripts/dialogs/perform-edits-dialog.js
index 65d481cfa..9c286292f 100644
--- a/extensions/wikidata/module/scripts/dialogs/perform-edits-dialog.js
+++ b/extensions/wikidata/module/scripts/dialogs/perform-edits-dialog.js
@@ -22,8 +22,10 @@ PerformEditsDialog.launch = function(logged_in_username) {
        "wikidata",
        "perform-wikibase-edits",
        {},
-       elmts.performEditsForm.serialize(),
-       {},
+       { strategy : "SNAK_QUALIFIERS",
+         action: "MERGE",
+       },
+       { includeEngine: true, cellsChanged: true, columnStatsChanged: true },
        { onDone:
           function() {
            dismiss();
diff --git a/extensions/wikidata/src/org/openrefine/wikidata/editing/CellCoordinates.java b/extensions/wikidata/src/org/openrefine/wikidata/editing/CellCoordinates.java
new file mode 100644
index 000000000..f64e69a1c
--- /dev/null
+++ b/extensions/wikidata/src/org/openrefine/wikidata/editing/CellCoordinates.java
@@ -0,0 +1,33 @@
+package org.openrefine.wikidata.editing;
+
+import com.fasterxml.jackson.annotation.JsonIgnore;
+
+
+/**
+ * A class to facilitate serialization of 
+ * the map from cell positions to qids
+ * 
+ * @author antonin
+ *
+ */
+public class CellCoordinates {
+    public int row;
+    public int col;
+    
+    public CellCoordinates(int row, int col) {
+        this.row = row;
+        this.col = col;
+    }
+    
+    public CellCoordinates(String serialized) {
+        String[] coords = serialized.split("_");
+        this.row = Integer.parseInt(coords[0]);
+        this.col = Integer.parseInt(coords[1]);
+    }
+    
+    @JsonIgnore
+    public String toString() {
+        return String.format("%d_%d", row, col);
+    }
+}
+
diff --git a/extensions/wikidata/src/org/openrefine/wikidata/editing/CellCoordinatesKeyDeserializer.java b/extensions/wikidata/src/org/openrefine/wikidata/editing/CellCoordinatesKeyDeserializer.java
new file mode 100644
index 000000000..12235783b
--- /dev/null
+++ b/extensions/wikidata/src/org/openrefine/wikidata/editing/CellCoordinatesKeyDeserializer.java
@@ -0,0 +1,18 @@
+package org.openrefine.wikidata.editing;
+
+import java.io.IOException;
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.DeserializationContext;
+import com.fasterxml.jackson.databind.KeyDeserializer;
+
+
+public class CellCoordinatesKeyDeserializer extends KeyDeserializer {
+
+    @Override
+    public Object deserializeKey(final String key, final DeserializationContext ctxt ) throws IOException, JsonProcessingException
+    {
+        return new CellCoordinates(key);
+    }
+
+}
diff --git a/extensions/wikidata/src/org/openrefine/wikidata/editing/NewItemLibrary.java b/extensions/wikidata/src/org/openrefine/wikidata/editing/NewItemLibrary.java
new file mode 100644
index 000000000..be2eb0c55
--- /dev/null
+++ b/extensions/wikidata/src/org/openrefine/wikidata/editing/NewItemLibrary.java
@@ -0,0 +1,104 @@
+package org.openrefine.wikidata.editing;
+
+import java.util.Map;
+import java.util.HashMap;
+import java.util.Set;
+import java.util.HashSet;
+
+import com.google.refine.model.Project;
+import com.google.refine.model.Cell;
+import com.google.refine.model.Column;
+import com.google.refine.model.Recon;
+import com.google.refine.model.ReconCandidate;
+import com.google.refine.model.ReconStats;
+
+import org.openrefine.wikidata.schema.NewEntityIdValue;
+
+/**
+ * This keeps track of the new items that we
+ * have created for each cell that was marked
+ * as such.
+ * 
+ * @author antonin
+ *
+ */
+public class NewItemLibrary {
+    
+    private Map<CellCoordinates, String> map;
+    
+    public NewItemLibrary() {
+        map = new HashMap<>();
+    }
+    
+    /**
+     * Retrieves the Qid allocated to a given new cell
+     * @param id: the fake ItemId generated by the cell
+     * @return the qid (or null if unallocated yet)
+     */
+    public String getQid(NewEntityIdValue id) {
+        return map.get(fromNewEntityIdValue(id));
+    }
+    
+    /**
+     * Stores a Qid associated to a new cell
+     * @param id : the fake EntityIdValue generated by the cell
+     * @param qid : the associated Qid returned by Wikibase
+     */
+    public void setQid(NewEntityIdValue id, String qid) {
+        map.put(fromNewEntityIdValue(id), qid);
+    }
+    
+    /**
+     * Changes the "new" reconciled cells to their allocated
+     * qids for later use.
+     * 
+     * @param reset: set to true to revert the operation (set cells to "new")
+     */
+    public void updateReconciledCells(Project project, boolean reset) {
+        Set<Integer> impactedColumns = new HashSet<>();
+        
+        for(Map.Entry<CellCoordinates, String> entry : map.entrySet()) {
+            CellCoordinates coords = entry.getKey();
+            Cell cell = project.rows.get(coords.row).getCell(coords.col);
+            Recon recon = cell.recon;
+            if (recon.judgment.equals(Recon.Judgment.New) && !reset) {
+                recon.judgment = Recon.Judgment.Matched;
+                recon.match = new ReconCandidate(
+                        entry.getValue(),
+                        cell.value.toString(),
+                        new String[0],
+                        100);
+            } else if (recon.judgment.equals(Recon.Judgment.Matched) && reset) {
+                recon.judgment = Recon.Judgment.New;
+                recon.match = null;
+            }
+            impactedColumns.add(coords.col);
+        }
+        
+        // Update reconciliation statistics for impacted columns
+        for(Integer colId : impactedColumns) {
+            Column column = project.columnModel.getColumnByCellIndex(colId);
+            column.setReconStats(ReconStats.create(project, colId));
+        }
+    }
+    
+    // TODO migrate NewEntityIdValue to use CellCoordinates directly
+    private CellCoordinates fromNewEntityIdValue(NewEntityIdValue id) {
+        return new CellCoordinates(id.getRowId(), id.getColId());
+    }
+    
+    /**
+     * Accessor, only meant to be used by Jackson
+     * @return the underlying map
+     */
+    public Map<CellCoordinates, String> getQidMap() {
+        return map;
+    }
+    
+    /**
+     * Accessor, only meant to be used by Jackson
+     */
+    public void setQidMap(Map<CellCoordinates, String> newMap) {
+        map = newMap;
+    }
+}
diff --git a/extensions/wikidata/src/org/openrefine/wikidata/exporters/QuickStatementsExporter.java b/extensions/wikidata/src/org/openrefine/wikidata/exporters/QuickStatementsExporter.java
index be5a16eff..9354e3c5f 100644
--- a/extensions/wikidata/src/org/openrefine/wikidata/exporters/QuickStatementsExporter.java
+++ b/extensions/wikidata/src/org/openrefine/wikidata/exporters/QuickStatementsExporter.java
@@ -73,7 +73,7 @@ public class QuickStatementsExporter implements WriterExporter {
     
     protected void translateItem(ItemUpdate item, Writer writer) throws IOException {
         String qid = item.getItemId().getId();
-        if (item.getItemId().equals(ItemIdValue.NULL)) {
+        if (item.getItemId().getId() == "Q0") {
             writer.write("CREATE\n");
             qid = "LAST";
         }
diff --git a/extensions/wikidata/src/org/openrefine/wikidata/operations/PerformWikibaseEditsOperation.java b/extensions/wikidata/src/org/openrefine/wikidata/operations/PerformWikibaseEditsOperation.java
index 7cc849a0f..49698c156 100644
--- a/extensions/wikidata/src/org/openrefine/wikidata/operations/PerformWikibaseEditsOperation.java
+++ b/extensions/wikidata/src/org/openrefine/wikidata/operations/PerformWikibaseEditsOperation.java
@@ -11,39 +11,40 @@ import java.util.Properties;
 import org.json.JSONException;
 import org.json.JSONObject;
 import org.json.JSONWriter;
-import com.google.common.collect.Lists;
 
 import org.openrefine.wikidata.editing.ConnectionManager;
-import org.openrefine.wikidata.operations.SaveWikibaseSchemaOperation.WikibaseSchemaChange;
+import org.openrefine.wikidata.editing.NewItemLibrary;
+import org.openrefine.wikidata.editing.CellCoordinates;
+import org.openrefine.wikidata.editing.CellCoordinatesKeyDeserializer;
 import org.openrefine.wikidata.schema.ItemUpdate;
+import org.openrefine.wikidata.schema.NewEntityIdValue;
 import org.openrefine.wikidata.schema.WikibaseSchema;
-import org.wikidata.wdtk.datamodel.helpers.EntityDocumentBuilder;
-import org.wikidata.wdtk.datamodel.helpers.ItemDocumentBuilder;
-import org.wikidata.wdtk.datamodel.interfaces.EntityDocument;
+import org.wikidata.wdtk.datamodel.implementation.DataObjectFactoryImpl;
+import org.wikidata.wdtk.datamodel.interfaces.DataObjectFactory;
 import org.wikidata.wdtk.datamodel.interfaces.EntityIdValue;
 import org.wikidata.wdtk.datamodel.interfaces.ItemDocument;
 import org.wikidata.wdtk.datamodel.interfaces.ItemIdValue;
 import org.wikidata.wdtk.util.WebResourceFetcherImpl;
 import org.wikidata.wdtk.wikibaseapi.ApiConnection;
-import org.wikidata.wdtk.wikibaseapi.LoginFailedException;
-import org.wikidata.wdtk.wikibaseapi.StatementUpdate;
 import org.wikidata.wdtk.wikibaseapi.WikibaseDataEditor;
-import org.wikidata.wdtk.wikibaseapi.WikibaseDataFetcher;
 import org.wikidata.wdtk.wikibaseapi.apierrors.MediaWikiApiErrorException;
-import org.wikidata.wdtk.datamodel.interfaces.Statement;
+import org.wikidata.wdtk.datamodel.interfaces.SiteLink;
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.DeserializationContext;
+import com.fasterxml.jackson.databind.KeyDeserializer;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.module.SimpleModule;
 
 import com.google.refine.browsing.Engine;
 import com.google.refine.history.Change;
 import com.google.refine.history.HistoryEntry;
 import com.google.refine.model.AbstractOperation;
 import com.google.refine.model.Project;
-import com.google.refine.model.changes.ReconChange;
 import com.google.refine.operations.EngineDependentOperation;
 import com.google.refine.operations.OperationRegistry;
-import com.google.refine.operations.recon.ReconOperation;
 import com.google.refine.process.LongRunningProcess;
 import com.google.refine.process.Process;
-import com.google.refine.util.ParsingUtilities;
 import com.google.refine.util.Pool;
 
 
@@ -113,27 +114,56 @@ public class PerformWikibaseEditsOperation extends EngineDependentOperation {
             "#openrefine"
         );
     }
+    
     static public class PerformWikibaseEditsChange implements Change {
+        
+        private NewItemLibrary newItemLibrary;
+        
+        public PerformWikibaseEditsChange(NewItemLibrary library) {
+            newItemLibrary = library;
+        }
 
         @Override
         public void apply(Project project) {
-            // this does not do anything to the project (we don't re-run changes on Wikidata)
+            // we don't re-run changes on Wikidata
+            newItemLibrary.updateReconciledCells(project, false);
         }
 
         @Override
         public void revert(Project project) {
-            // this does not do anything (we don't revert changes on Wikidata either)
+            // this does not do anything on Wikibase side - 
+            // (we don't revert changes on Wikidata either)
+            newItemLibrary.updateReconciledCells(project, true);
         }
 
         @Override
         public void save(Writer writer, Properties options)
                 throws IOException {
+            if (newItemLibrary != null) {
+                writer.write("newItems=");
+                ObjectMapper mapper = new ObjectMapper();
+                writer.write(mapper.writeValueAsString(newItemLibrary)+"\n");
+            }
             writer.write("/ec/\n"); // end of change
         }
         
         static public Change load(LineNumberReader reader, Pool pool)
                 throws Exception {
-            return new PerformWikibaseEditsChange();
+            NewItemLibrary library = new NewItemLibrary();
+            String line = null;
+            while ((line = reader.readLine()) != null && !"/ec/".equals(line)) {
+                int equal = line.indexOf('=');
+                CharSequence field = line.subSequence(0, equal);
+                String value = line.substring(equal + 1);
+                
+                if ("newItems".equals(field)) {
+                    ObjectMapper mapper = new ObjectMapper();
+                    SimpleModule simpleModule = new SimpleModule();
+                    simpleModule.addKeyDeserializer(CellCoordinates.class, new CellCoordinatesKeyDeserializer());
+                    library = mapper.readValue(value, NewItemLibrary.class);
+                }
+            }
+            return new PerformWikibaseEditsChange(library);
         }
         
     }
@@ -175,20 +205,7 @@ public class PerformWikibaseEditsOperation extends EngineDependentOperation {
             List<ItemUpdate> itemDocuments = _schema.evaluate(_project, _engine);
             
             // Group statements by item
-            Map<EntityIdValue, ItemUpdate> updates = new HashMap<EntityIdValue, ItemUpdate>();
-            for(ItemUpdate update : itemDocuments) {
-                if (update.isNull()) {
-                    continue;
-                }
-                
-                ItemIdValue qid = update.getItemId();
-                if (updates.containsKey(qid)) {
-                    ItemUpdate oldUpdate = updates.get(qid);
-                    oldUpdate.merge(update);
-                } else {
-                    updates.put(qid, update);
-                }
-            }
+            Map<EntityIdValue, ItemUpdate> updates =  ItemUpdate.groupBySubject(itemDocuments);
             
             /**
              * TODO:
@@ -197,12 +214,32 @@ public class PerformWikibaseEditsOperation extends EngineDependentOperation {
              */
             
             // Perform edits
+            NewItemLibrary newItemLibrary = new NewItemLibrary();
+            DataObjectFactory factory = new DataObjectFactoryImpl();
             int totalItemUpdates = updates.size();
             int updatesDone = 0;
             for(ItemUpdate update : updates.values()) {
                 try {
-                    wbde.updateStatements(update.getItemId(), update.getAddedStatements(), update.getDeletedStatements(), _summary);
-                    
+                    // New item
+                    if (update.getItemId().getId() == "Q0") {
+                        NewEntityIdValue newCell = (NewEntityIdValue)update.getItemId();
+                        ItemDocument itemDocument = factory.getItemDocument(
+                                update.getItemId(),
+                                update.getLabels(),
+                                update.getDescriptions(),
+                                update.getAliases(),
+                                update.getAddedStatementGroups(),
+                                new HashMap<String,SiteLink>(),
+                                0L);
+                                
+                        ItemDocument createdDoc = wbde.createItemDocument(itemDocument, _summary);
+                        newItemLibrary.setQid(newCell, createdDoc.getItemId().getId());
+                    } else {
+                        // Existing item
+                        wbde.updateStatements(update.getItemId(),
+                                update.getAddedStatements(),
+                                update.getDeletedStatements(), _summary);   
+                    }
                 } catch (MediaWikiApiErrorException e) {
                     // TODO Auto-generated catch block
                     e.printStackTrace();
@@ -221,7 +258,7 @@ public class PerformWikibaseEditsOperation extends EngineDependentOperation {
             _progress = 100;
             
             if (!_canceled) {
-                Change change = new PerformWikibaseEditsChange();
+                Change change = new PerformWikibaseEditsChange(newItemLibrary);
                 
                 HistoryEntry historyEntry = new HistoryEntry(
                     _historyEntryID,
diff --git a/extensions/wikidata/src/org/openrefine/wikidata/schema/ExpressionContext.java b/extensions/wikidata/src/org/openrefine/wikidata/schema/ExpressionContext.java
index 25d0df613..c66970332 100644
--- a/extensions/wikidata/src/org/openrefine/wikidata/schema/ExpressionContext.java
+++ b/extensions/wikidata/src/org/openrefine/wikidata/schema/ExpressionContext.java
@@ -7,11 +7,13 @@ import com.google.refine.model.Row;
 
 public class ExpressionContext {
     private String baseIRI;
+    private int rowId;
     private Row row;
     private ColumnModel columnModel;
     
-    public ExpressionContext(String baseIRI, Row row, ColumnModel columnModel) {
+    public ExpressionContext(String baseIRI, int rowId, Row row, ColumnModel columnModel) {
         this.baseIRI = baseIRI;
+        this.rowId = rowId;
         this.row = row;
         this.columnModel = columnModel;
     }
@@ -20,8 +22,16 @@ public class ExpressionContext {
         return baseIRI;
     }
     
+    public int getCellIndexByName(String name) {
+        return columnModel.getColumnByName(name).getCellIndex();
+    }
+    
     public Cell getCellByName(String name) {
-        int idx = columnModel.getColumnByName(name).getCellIndex();
+        int idx = getCellIndexByName(name);
         return row.getCell(idx);
     }
+    
+    public int getRowId() {
+        return rowId;
+    }
 }
diff --git a/extensions/wikidata/src/org/openrefine/wikidata/schema/ItemUpdate.java b/extensions/wikidata/src/org/openrefine/wikidata/schema/ItemUpdate.java
index d7b68a9ce..172fe328e 100644
--- a/extensions/wikidata/src/org/openrefine/wikidata/schema/ItemUpdate.java
+++ b/extensions/wikidata/src/org/openrefine/wikidata/schema/ItemUpdate.java
@@ -2,10 +2,16 @@ package org.openrefine.wikidata.schema;
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Map;
+import java.util.HashMap;
 
+import org.wikidata.wdtk.datamodel.implementation.StatementGroupImpl;
+import org.wikidata.wdtk.datamodel.interfaces.EntityIdValue;
+import org.wikidata.wdtk.datamodel.interfaces.PropertyIdValue;
 import org.wikidata.wdtk.datamodel.interfaces.ItemIdValue;
 import org.wikidata.wdtk.datamodel.interfaces.MonolingualTextValue;
 import org.wikidata.wdtk.datamodel.interfaces.Statement;
+import org.wikidata.wdtk.datamodel.interfaces.StatementGroup;
 
 
 /**
@@ -103,4 +109,51 @@ public class ItemUpdate {
     public List<MonolingualTextValue> getAliases() {
         return aliases;
     }
+    
+    /**
+     * Group added statements in StatementGroups: useful if the
+     * item is new.
+     * 
+     * @return a grouped version of getAddedStatements()
+     */
+    public List<StatementGroup> getAddedStatementGroups() {
+        Map<PropertyIdValue, List<Statement>> map = new HashMap<>();
+        for(Statement statement : getAddedStatements()) {
+            PropertyIdValue propertyId = statement.getClaim().getMainSnak().getPropertyId();
+            if (!map.containsKey(propertyId)) {
+                map.put(propertyId, new ArrayList<Statement>());
+            }
+            map.get(propertyId).add(statement);
+        }
+        List<StatementGroup> result = new ArrayList<>();
+        for(Map.Entry<PropertyIdValue, List<Statement>> entry : map.entrySet()) {
+            result.add(new StatementGroupImpl(entry.getValue()));
+        }
+        return result;
+    }
+
+    /**
+     * Group a list of ItemUpdates by subject: this is useful to make one single edit
+     * per item.
+     * 
+     * @param itemDocuments
+     * @return a map from item ids to merged ItemUpdate for that id
+     */
+    public static Map<EntityIdValue, ItemUpdate> groupBySubject(List<ItemUpdate> itemDocuments) {
+        Map<EntityIdValue, ItemUpdate> map = new HashMap<EntityIdValue, ItemUpdate>();
+        for(ItemUpdate update : itemDocuments) {
+            if (update.isNull()) {
+                continue;
+            }
+            
+            ItemIdValue qid = update.getItemId();
+            if (map.containsKey(qid)) {
+                ItemUpdate oldUpdate = map.get(qid);
+                oldUpdate.merge(update);
+            } else {
+                map.put(qid, update);
+            }
+        }
+        return map;
+    }
 }
diff --git a/extensions/wikidata/src/org/openrefine/wikidata/schema/NewEntityIdValue.java b/extensions/wikidata/src/org/openrefine/wikidata/schema/NewEntityIdValue.java
new file mode 100644
index 000000000..13adcdc84
--- /dev/null
+++ b/extensions/wikidata/src/org/openrefine/wikidata/schema/NewEntityIdValue.java
@@ -0,0 +1,90 @@
+package org.openrefine.wikidata.schema;
+
+import org.wikidata.wdtk.datamodel.interfaces.EntityIdValue;
+import org.wikidata.wdtk.datamodel.interfaces.ItemIdValue;
+import org.wikidata.wdtk.datamodel.interfaces.ValueVisitor;
+
+/**
+ * A placeholder for the Qid of a new item, which
+ * also remembers from which reconciled cell it was
+ * generated. This allows us to make sure that we will
+ * create only one item per cell marked as "new".
+ * 
+ * @author antonin
+ */
+public class NewEntityIdValue implements ItemIdValue {
+    
+    private final int rowId;
+    private final int colId;
+    
+    /**
+     * Creates a new entity id corresponding to the
+     * cell designated by the indices.
+     * 
+     * @param rowId
+     *          the index of the row for the cell
+     * @param colId
+     *          the index of the column for the cell
+     */
+    public NewEntityIdValue(int rowId, int colId) {
+        this.rowId = rowId;
+        this.colId = colId;
+    }
+    
+    public int getRowId() {
+        return rowId;
+    }
+    
+    public int getColId() {
+        return colId;
+    }
+    
+    /**
+     * Equality check is important when we gather
+     * all ItemUpdates related to an ItemId.
+     */
+    @Override
+    public boolean equals(Object other) {
+        if (other == null ||
+            !NewEntityIdValue.class.isInstance(other)) {
+            return false;
+        }
+        final NewEntityIdValue otherNew = (NewEntityIdValue)other;
+        return (rowId == otherNew.getRowId() &&
+                colId == otherNew.getColId());
+    }
+    
+    @Override
+    public int hashCode() {
+        int hash = 3;
+        hash = 41*hash + rowId;
+        hash = 41*hash + colId;
+        return hash;
+    }
+    
+    @Override
+    public String getIri() {
+            return getSiteIri() + getId();
+    }
+
+    @Override
+    public <T> T accept(ValueVisitor<T> valueVisitor) {
+            return valueVisitor.visit(this);
+    }
+
+    @Override
+    public String getEntityType() {
+            return ET_ITEM;
+    }
+
+    @Override
+    public String getId() {
+            return "Q0";
+    }
+
+    @Override
+    public String getSiteIri() {
+            return EntityIdValue.SITE_LOCAL;
+    }
+
+}
diff --git a/extensions/wikidata/src/org/openrefine/wikidata/schema/WbItemVariable.java b/extensions/wikidata/src/org/openrefine/wikidata/schema/WbItemVariable.java
index 9741afe8d..fcaa3d6de 100644
--- a/extensions/wikidata/src/org/openrefine/wikidata/schema/WbItemVariable.java
+++ b/extensions/wikidata/src/org/openrefine/wikidata/schema/WbItemVariable.java
@@ -44,7 +44,8 @@ public class WbItemVariable extends WbItemExpr {
                 ReconCandidate match = cell.recon.match;
                 return Datamodel.makeItemIdValue(match.id, ctxt.getBaseIRI());
             } else if (recon.judgment == Recon.Judgment.New) {
-                return ItemIdValue.NULL;
+                return new NewEntityIdValue(ctxt.getRowId(),
+                        ctxt.getCellIndexByName(columnName));
             }
         }
         throw new SkipStatementException();
diff --git a/extensions/wikidata/src/org/openrefine/wikidata/schema/WbNameDescExpr.java b/extensions/wikidata/src/org/openrefine/wikidata/schema/WbNameDescExpr.java
index 3b1697782..465ec4222 100644
--- a/extensions/wikidata/src/org/openrefine/wikidata/schema/WbNameDescExpr.java
+++ b/extensions/wikidata/src/org/openrefine/wikidata/schema/WbNameDescExpr.java
@@ -31,7 +31,7 @@ public class WbNameDescExpr extends BiJsonizable {
             throws JSONException {
         writer.key("name_type");
         writer.value(_type.name());
-        writer.value("value");
+        writer.key("value");
         _value.write(writer, options);
     }
     
diff --git a/extensions/wikidata/src/org/openrefine/wikidata/schema/WikibaseSchema.java b/extensions/wikidata/src/org/openrefine/wikidata/schema/WikibaseSchema.java
index 7ec06fb6a..14b1fdcae 100644
--- a/extensions/wikidata/src/org/openrefine/wikidata/schema/WikibaseSchema.java
+++ b/extensions/wikidata/src/org/openrefine/wikidata/schema/WikibaseSchema.java
@@ -96,7 +96,7 @@ public class WikibaseSchema implements OverlayModel {
 
         @Override
         public boolean visit(Project project, int rowIndex, Row row) {
-            ExpressionContext ctxt = new ExpressionContext(baseUri, row, project.columnModel);
+            ExpressionContext ctxt = new ExpressionContext(baseUri, rowIndex, row, project.columnModel);
             result.addAll(evaluateItemDocuments(ctxt));
             return false;
         }