/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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 org.apache.lucene.queries.spans;

import static org.apache.lucene.queries.spans.SpanTestUtil.assertFinished;
import static org.apache.lucene.queries.spans.SpanTestUtil.assertNext;

import java.util.HashSet;
import java.util.Set;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.Term;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.QueryVisitor;
import org.apache.lucene.search.ScoreMode;
import org.apache.lucene.search.similarities.TFIDFSimilarity;
import org.apache.lucene.store.Directory;
import org.apache.lucene.tests.analysis.MockAnalyzer;
import org.apache.lucene.tests.index.RandomIndexWriter;
import org.apache.lucene.tests.search.CheckHits;
import org.apache.lucene.tests.search.QueryUtils;
import org.apache.lucene.tests.util.LuceneTestCase;
import org.junit.AfterClass;
import org.junit.BeforeClass;

public class TestFieldMaskingSpanQuery extends LuceneTestCase {

  protected static Document doc(Field[] fields) {
    Document doc = new Document();
    for (int i = 0; i < fields.length; i++) {
      doc.add(fields[i]);
    }
    return doc;
  }

  protected static Field field(String name, String value) {
    return newTextField(name, value, Field.Store.NO);
  }

  protected static IndexSearcher searcher;
  protected static Directory directory;
  protected static IndexReader reader;

  @BeforeClass
  public static void beforeClass() throws Exception {
    directory = newDirectory();
    RandomIndexWriter writer =
        new RandomIndexWriter(
            random(),
            directory,
            newIndexWriterConfig(new MockAnalyzer(random())).setMergePolicy(newLogMergePolicy()));

    writer.addDocument(
        doc(
            new Field[] {
              field("id", "0"),
              field("gender", "male"),
              field("first", "james"),
              field("last", "jones")
            }));

    writer.addDocument(
        doc(
            new Field[] {
              field("id", "1"),
              field("gender", "male"),
              field("first", "james"),
              field("last", "smith"),
              field("gender", "female"),
              field("first", "sally"),
              field("last", "jones")
            }));

    writer.addDocument(
        doc(
            new Field[] {
              field("id", "2"),
              field("gender", "female"),
              field("first", "greta"),
              field("last", "jones"),
              field("gender", "female"),
              field("first", "sally"),
              field("last", "smith"),
              field("gender", "male"),
              field("first", "james"),
              field("last", "jones")
            }));

    writer.addDocument(
        doc(
            new Field[] {
              field("id", "3"),
              field("gender", "female"),
              field("first", "lisa"),
              field("last", "jones"),
              field("gender", "male"),
              field("first", "bob"),
              field("last", "costas")
            }));

    writer.addDocument(
        doc(
            new Field[] {
              field("id", "4"),
              field("gender", "female"),
              field("first", "sally"),
              field("last", "smith"),
              field("gender", "female"),
              field("first", "linda"),
              field("last", "dixit"),
              field("gender", "male"),
              field("first", "bubba"),
              field("last", "jones")
            }));
    writer.forceMerge(1);
    reader = writer.getReader();
    writer.close();
    searcher = new IndexSearcher(getOnlyLeafReader(reader));
  }

  @AfterClass
  public static void afterClass() throws Exception {
    searcher = null;
    reader.close();
    reader = null;
    directory.close();
    directory = null;
  }

  protected void check(SpanQuery q, int[] docs) throws Exception {
    CheckHits.checkHitCollector(random(), q, null, searcher, docs);
  }

  public void testRewrite0() throws Exception {
    SpanQuery q = new FieldMaskingSpanQuery(new SpanTermQuery(new Term("last", "sally")), "first");
    SpanQuery qr = (SpanQuery) searcher.rewrite(q);

    QueryUtils.checkEqual(q, qr);

    Set<Term> terms = new HashSet<>();
    qr.visit(QueryVisitor.termCollector(terms));
    assertEquals(1, terms.size());
  }

  public void testRewrite1() throws Exception {
    // mask an anon SpanQuery class that rewrites to something else.
    SpanQuery q =
        new FieldMaskingSpanQuery(
            new SpanTermQuery(new Term("last", "sally")) {
              @Override
              public Query rewrite(IndexSearcher indexSearcher) {
                return new SpanOrQuery(
                    new SpanTermQuery(new Term("first", "sally")),
                    new SpanTermQuery(new Term("first", "james")));
              }
            },
            "first");

    SpanQuery qr = (SpanQuery) searcher.rewrite(q);

    QueryUtils.checkUnequal(q, qr);

    Set<Term> terms = new HashSet<>();
    qr.visit(QueryVisitor.termCollector(terms));
    assertEquals(2, terms.size());
  }

  public void testRewrite2() throws Exception {
    SpanQuery q1 = new SpanTermQuery(new Term("last", "smith"));
    SpanQuery q2 = new SpanTermQuery(new Term("last", "jones"));
    SpanQuery q =
        new SpanNearQuery(new SpanQuery[] {q1, new FieldMaskingSpanQuery(q2, "last")}, 1, true);
    Query qr = searcher.rewrite(q);

    QueryUtils.checkEqual(q, qr);

    HashSet<Term> set = new HashSet<>();
    qr.visit(QueryVisitor.termCollector(set));
    assertEquals(2, set.size());
  }

  public void testEquality1() {
    SpanQuery q1 = new FieldMaskingSpanQuery(new SpanTermQuery(new Term("last", "sally")), "first");
    SpanQuery q2 = new FieldMaskingSpanQuery(new SpanTermQuery(new Term("last", "sally")), "first");
    SpanQuery q3 = new FieldMaskingSpanQuery(new SpanTermQuery(new Term("last", "sally")), "XXXXX");
    SpanQuery q4 = new FieldMaskingSpanQuery(new SpanTermQuery(new Term("last", "XXXXX")), "first");
    SpanQuery q5 = new FieldMaskingSpanQuery(new SpanTermQuery(new Term("xXXX", "sally")), "first");
    QueryUtils.checkEqual(q1, q2);
    QueryUtils.checkUnequal(q1, q3);
    QueryUtils.checkUnequal(q1, q4);
    QueryUtils.checkUnequal(q1, q5);
  }

  public void testNoop0() throws Exception {
    SpanQuery q1 = new SpanTermQuery(new Term("last", "sally"));
    SpanQuery q = new FieldMaskingSpanQuery(q1, "first");
    check(
        q,
        new int[] {
          /* :EMPTY: */
        });
  }

  public void testNoop1() throws Exception {
    SpanQuery q1 = new SpanTermQuery(new Term("last", "smith"));
    SpanQuery q2 = new SpanTermQuery(new Term("last", "jones"));
    SpanQuery q =
        new SpanNearQuery(new SpanQuery[] {q1, new FieldMaskingSpanQuery(q2, "last")}, 0, true);
    check(q, new int[] {1, 2});
    q =
        new SpanNearQuery(
            new SpanQuery[] {
              new FieldMaskingSpanQuery(q1, "last"), new FieldMaskingSpanQuery(q2, "last")
            },
            0,
            true);
    check(q, new int[] {1, 2});
  }

  public void testSimple1() throws Exception {
    SpanQuery q1 = new SpanTermQuery(new Term("first", "james"));
    SpanQuery q2 = new SpanTermQuery(new Term("last", "jones"));
    SpanQuery q =
        new SpanNearQuery(new SpanQuery[] {q1, new FieldMaskingSpanQuery(q2, "first")}, -1, false);
    check(q, new int[] {0, 2});
    q = new SpanNearQuery(new SpanQuery[] {new FieldMaskingSpanQuery(q2, "first"), q1}, -1, false);
    check(q, new int[] {0, 2});
    q = new SpanNearQuery(new SpanQuery[] {q2, new FieldMaskingSpanQuery(q1, "last")}, -1, false);
    check(q, new int[] {0, 2});
    q = new SpanNearQuery(new SpanQuery[] {new FieldMaskingSpanQuery(q1, "last"), q2}, -1, false);
    check(q, new int[] {0, 2});
  }

  public void testSimple2() throws Exception {
    assumeTrue("Broken scoring: LUCENE-3723", searcher.getSimilarity() instanceof TFIDFSimilarity);
    SpanQuery q1 = new SpanTermQuery(new Term("gender", "female"));
    SpanQuery q2 = new SpanTermQuery(new Term("last", "smith"));
    SpanQuery q =
        new SpanNearQuery(new SpanQuery[] {q1, new FieldMaskingSpanQuery(q2, "gender")}, -1, false);
    check(q, new int[] {2, 4});
    q =
        new SpanNearQuery(
            new SpanQuery[] {
              new FieldMaskingSpanQuery(q1, "id"), new FieldMaskingSpanQuery(q2, "id")
            },
            -1,
            false);
    check(q, new int[] {2, 4});
  }

  public void testSpans0() throws Exception {
    SpanQuery q1 = new SpanTermQuery(new Term("gender", "female"));
    SpanQuery q2 = new SpanTermQuery(new Term("first", "james"));
    SpanQuery q = new SpanOrQuery(q1, new FieldMaskingSpanQuery(q2, "gender"));
    check(q, new int[] {0, 1, 2, 3, 4});

    Spans span =
        q.createWeight(searcher, ScoreMode.COMPLETE_NO_SCORES, 1f)
            .getSpans(searcher.getIndexReader().leaves().get(0), SpanWeight.Postings.POSITIONS);
    assertNext(span, 0, 0, 1);
    assertNext(span, 1, 0, 1);
    assertNext(span, 1, 1, 2);
    assertNext(span, 2, 0, 1);
    assertNext(span, 2, 1, 2);
    assertNext(span, 2, 2, 3);
    assertNext(span, 3, 0, 1);
    assertNext(span, 4, 0, 1);
    assertNext(span, 4, 1, 2);
    assertFinished(span);
  }

  public void testSpans1() throws Exception {
    SpanQuery q1 = new SpanTermQuery(new Term("first", "sally"));
    SpanQuery q2 = new SpanTermQuery(new Term("first", "james"));
    SpanQuery qA = new SpanOrQuery(q1, q2);
    SpanQuery qB = new FieldMaskingSpanQuery(qA, "id");

    check(qA, new int[] {0, 1, 2, 4});
    check(qB, new int[] {0, 1, 2, 4});

    Spans spanA =
        qA.createWeight(searcher, ScoreMode.COMPLETE_NO_SCORES, 1f)
            .getSpans(searcher.getIndexReader().leaves().get(0), SpanWeight.Postings.POSITIONS);
    Spans spanB =
        qB.createWeight(searcher, ScoreMode.COMPLETE_NO_SCORES, 1f)
            .getSpans(searcher.getIndexReader().leaves().get(0), SpanWeight.Postings.POSITIONS);

    while (spanA.nextDoc() != Spans.NO_MORE_DOCS) {
      assertNotSame("spanB not still going", Spans.NO_MORE_DOCS, spanB.nextDoc());
      while (spanA.nextStartPosition() != Spans.NO_MORE_POSITIONS) {
        assertEquals("spanB start position", spanA.startPosition(), spanB.nextStartPosition());
        assertEquals("spanB end position", spanA.endPosition(), spanB.endPosition());
      }
      assertEquals("spanB start position", Spans.NO_MORE_POSITIONS, spanB.nextStartPosition());
    }
    assertEquals("spanB end doc", Spans.NO_MORE_DOCS, spanB.nextDoc());
  }

  public void testSpans2() throws Exception {
    assumeTrue("Broken scoring: LUCENE-3723", searcher.getSimilarity() instanceof TFIDFSimilarity);
    SpanQuery qA1 = new SpanTermQuery(new Term("gender", "female"));
    SpanQuery qA2 = new SpanTermQuery(new Term("first", "james"));
    SpanQuery qA = new SpanOrQuery(qA1, new FieldMaskingSpanQuery(qA2, "gender"));
    SpanQuery qB = new SpanTermQuery(new Term("last", "jones"));
    SpanQuery q =
        new SpanNearQuery(
            new SpanQuery[] {
              new FieldMaskingSpanQuery(qA, "id"), new FieldMaskingSpanQuery(qB, "id")
            },
            -1,
            false);
    check(q, new int[] {0, 1, 2, 3});

    Spans span =
        q.createWeight(searcher, ScoreMode.COMPLETE_NO_SCORES, 1f)
            .getSpans(searcher.getIndexReader().leaves().get(0), SpanWeight.Postings.POSITIONS);
    assertNext(span, 0, 0, 1);
    assertNext(span, 1, 1, 2);
    assertNext(span, 2, 0, 1);
    assertNext(span, 2, 2, 3);
    assertNext(span, 3, 0, 1);
    assertFinished(span);
  }

  public String s(int doc, int start, int end) {
    return "s(" + doc + "," + start + "," + end + ")";
  }
}
