/*
 * 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.search.vectorhighlight;
import org.apache.lucene.index.Term;
import org.apache.lucene.search.BooleanQuery;
import org.apache.lucene.search.BooleanClause.Occur;
import org.apache.lucene.search.WildcardQuery;
import org.apache.lucene.search.vectorhighlight.FieldTermStack.TermInfo;
import org.apache.lucene.util.TestUtil;

public class FieldTermStackTest extends AbstractTestCase {
  
  public void test1Term() throws Exception {
    makeIndex();
    
    FieldQuery fq = new FieldQuery( tq( "a" ), true, true );
    FieldTermStack stack = new FieldTermStack( reader, 0, F, fq );
    assertEquals( 6, stack.termList.size() );
    assertEquals( "a(0,1,0)", stack.pop().toString() );
    assertEquals( "a(2,3,1)", stack.pop().toString() );
    assertEquals( "a(4,5,2)", stack.pop().toString() );
    assertEquals( "a(12,13,6)", stack.pop().toString() );
    assertEquals( "a(28,29,14)", stack.pop().toString() );
    assertEquals( "a(32,33,16)", stack.pop().toString() );
  }
  
  public void test2Terms() throws Exception {
    makeIndex();
    
    BooleanQuery.Builder query = new BooleanQuery.Builder();
    query.add( tq( "b" ), Occur.SHOULD );
    query.add( tq( "c" ), Occur.SHOULD );
    FieldQuery fq = new FieldQuery( query.build(), true, true );
    FieldTermStack stack = new FieldTermStack( reader, 0, F, fq );
    assertEquals( 8, stack.termList.size() );
    assertEquals( "b(6,7,3)", stack.pop().toString() );
    assertEquals( "b(8,9,4)", stack.pop().toString() );
    assertEquals( "c(10,11,5)", stack.pop().toString() );
    assertEquals( "b(14,15,7)", stack.pop().toString() );
    assertEquals( "b(16,17,8)", stack.pop().toString() );
    assertEquals( "c(18,19,9)", stack.pop().toString() );
    assertEquals( "b(26,27,13)", stack.pop().toString() );
    assertEquals( "b(30,31,15)", stack.pop().toString() );
  }
  
  public void test1Phrase() throws Exception {
    makeIndex();
    
    FieldQuery fq = new FieldQuery( pqF( "c", "d" ), true, true );
    FieldTermStack stack = new FieldTermStack( reader, 0, F, fq );
    assertEquals( 3, stack.termList.size() );
    assertEquals( "c(10,11,5)", stack.pop().toString() );
    assertEquals( "c(18,19,9)", stack.pop().toString() );
    assertEquals( "d(20,21,10)", stack.pop().toString() );
  }
  
  private void makeIndex() throws Exception {
    //           111111111122222
    // 0123456789012345678901234 (offsets)
    // a a a b b c a b b c d e f
    // 0 1 2 3 4 5 6 7 8 9101112 (position)
    String value1 = "a a a b b c a b b c d e f";
    // 222233333
    // 678901234 (offsets)
    // b a b a f
    //1314151617 (position)
    String value2 = "b a b a f";
    
    make1dmfIndex( value1, value2 );
  }
  
  public void test1TermB() throws Exception {
    makeIndexB();
    
    FieldQuery fq = new FieldQuery( tq( "ab" ), true, true );
    FieldTermStack stack = new FieldTermStack( reader, 0, F, fq );
    assertEquals( 2, stack.termList.size() );
    assertEquals( "ab(2,4,2)", stack.pop().toString() );
    assertEquals( "ab(6,8,6)", stack.pop().toString() );
  }
  
  public void test2TermsB() throws Exception {
    makeIndexB();
    
    BooleanQuery.Builder query = new BooleanQuery.Builder();
    query.add( tq( "bc" ), Occur.SHOULD );
    query.add( tq( "ef" ), Occur.SHOULD );
    FieldQuery fq = new FieldQuery( query.build(), true, true );
    FieldTermStack stack = new FieldTermStack( reader, 0, F, fq );
    assertEquals( 3, stack.termList.size() );
    assertEquals( "bc(4,6,4)", stack.pop().toString() );
    assertEquals( "bc(8,10,8)", stack.pop().toString() );
    assertEquals( "ef(11,13,11)", stack.pop().toString() );
  }
  
  public void test1PhraseB() throws Exception {
    makeIndexB();
    
    FieldQuery fq = new FieldQuery( pqF( "ab", "bb" ), true, true );
    FieldTermStack stack = new FieldTermStack( reader, 0, F, fq );
    assertEquals( 4, stack.termList.size() );
    assertEquals( "ab(2,4,2)", stack.pop().toString() );
    assertEquals( "bb(3,5,3)", stack.pop().toString() );
    assertEquals( "ab(6,8,6)", stack.pop().toString() );
    assertEquals( "bb(7,9,7)", stack.pop().toString() );
  }
  
  private void makeIndexB() throws Exception {
    //                             1 11 11
    // 01 12 23 34 45 56 67 78 89 90 01 12 (offsets)
    // aa|aa|ab|bb|bc|ca|ab|bb|bc|cd|de|ef
    //  0  1  2  3  4  5  6  7  8  9 10 11 (position)
    String value = "aaabbcabbcdef";
    
    make1dmfIndexB( value );
  }
  
  public void test1PhraseShortMV() throws Exception {
    makeIndexShortMV();
    
    FieldQuery fq = new FieldQuery( tq( "d" ), true, true );
    FieldTermStack stack = new FieldTermStack( reader, 0, F, fq );
    assertEquals( 1, stack.termList.size() );
    assertEquals( "d(9,10,3)", stack.pop().toString() );
  }
  
  public void test1PhraseLongMV() throws Exception {
    makeIndexLongMV();
    
    FieldQuery fq = new FieldQuery( pqF( "search", "engines" ), true, true );
    FieldTermStack stack = new FieldTermStack( reader, 0, F, fq );
    assertEquals( 4, stack.termList.size() );
    assertEquals( "search(102,108,14)", stack.pop().toString() );
    assertEquals( "engines(109,116,15)", stack.pop().toString() );
    assertEquals( "search(157,163,24)", stack.pop().toString() );
    assertEquals( "engines(164,171,25)", stack.pop().toString() );
  }

  public void test1PhraseMVB() throws Exception {
    makeIndexLongMVB();
    
    FieldQuery fq = new FieldQuery( pqF( "sp", "pe", "ee", "ed" ), true, true ); // "speed" -(2gram)-> "sp","pe","ee","ed"
    FieldTermStack stack = new FieldTermStack( reader, 0, F, fq );
    assertEquals( 4, stack.termList.size() );
    assertEquals( "sp(88,90,61)", stack.pop().toString() );
    assertEquals( "pe(89,91,62)", stack.pop().toString() );
    assertEquals( "ee(90,92,63)", stack.pop().toString() );
    assertEquals( "ed(91,93,64)", stack.pop().toString() );
  }

  
  public void testWildcard() throws Exception {
    makeIndexLongMV();
    FieldQuery fq = new FieldQuery( new WildcardQuery (new Term(F, "th*e")), reader, true, true );
    FieldTermStack stack = new FieldTermStack( reader, 0, F, fq );
    assertEquals (4, stack.termList.size());
    assertEquals ("the(15,18,2)", stack.pop().toString());
    assertEquals ("these(133,138,20)", stack.pop().toString());
    assertEquals ("the(153,156,23)", stack.pop().toString());
    assertEquals ("the(195,198,31)", stack.pop().toString());
  }

  public void testTermInfoComparisonConsistency() {
    TermInfo a = new TermInfo( TestUtil.randomUnicodeString(random()), 0, 0, 0, 1 );
    TermInfo b = new TermInfo( TestUtil.randomUnicodeString(random()), 0, 0, 1, 1 );
    TermInfo c = new TermInfo( TestUtil.randomUnicodeString(random()), 0, 0, 2, 1 );
    TermInfo d = new TermInfo( TestUtil.randomUnicodeString(random()), 0, 0, 0, 1 );

    assertConsistentEquals( a, a );
    assertConsistentEquals( b, b );
    assertConsistentEquals( c, c );
    assertConsistentEquals( d, d );
    assertConsistentEquals( a, d );
    assertConsistentLessThan( a, b );
    assertConsistentLessThan( b, c );
    assertConsistentLessThan( a, c );
    assertConsistentLessThan( d, b );
    assertConsistentLessThan( d, c );
  }

  private < T extends Comparable< T > > void assertConsistentEquals( T a, T b ) {
    assertEquals( a, b );
    assertEquals( b, a );
    assertEquals( a.hashCode(), b.hashCode() );
    assertEquals( 0, a.compareTo( b ) );
    assertEquals( 0, b.compareTo( a ) );
  }

  private < T extends Comparable< T > > void assertConsistentLessThan( T a, T b ) {
    assertFalse( a.equals( b ) );
    assertFalse( b.equals( a ) );
    assertFalse( a.hashCode() == b.hashCode() );
    assertTrue( a.compareTo( b ) < 0 );
    assertTrue( b.compareTo( a ) > 0 );
  }
}