lib-php/TokenPartial.php

   1 <?php
   2 /**
   3  * SPDX-License-Identifier: GPL-2.0-only
   4  *
   5  * This file is part of Nominatim. (https://nominatim.org)
   6  *
   7  * Copyright (C) 2022 by the Nominatim developer community.
   8  * For a full list of authors see the git log.
   9  */
  10
  11 namespace Nominatim\Token;
  12
  13 /**
  14  * A standard word token.
  15  */
  16 class Partial
  17 {
  18     /// Database word id, if applicable.
  19     private $iId;
  20     /// Number of appearances in the database.
  21     private $iSearchNameCount;
  22     /// True, if the token consists exclusively of digits and spaces.
  23     private $bNumberToken;
  24
  25     public function __construct($iId, $sToken, $iSearchNameCount)
  26     {
  27         $this->iId = $iId;
  28         $this->bNumberToken = (bool) preg_match('#^[0-9 ]+$#', $sToken);
  29         $this->iSearchNameCount = $iSearchNameCount;
  30     }
  31
  32     public function getId()
  33     {
  34         return $this->iId;
  35     }
  36
  37     /**
  38      * Check if the token can be added to the given search.
  39      * Derive new searches by adding this token to an existing search.
  40      *
  41      * @param object  $oSearch      Partial search description derived so far.
  42      * @param object  $oPosition    Description of the token position within
  43                                     the query.
  44      *
  45      * @return True if the token is compatible with the search configuration
  46      *         given the position.
  47      */
  48     public function isExtendable($oSearch, $oPosition)
  49     {
  50         return !$oPosition->isPhrase('country');
  51     }
  52
  53     /**
  54      * Derive new searches by adding this token to an existing search.
  55      *
  56      * @param object  $oSearch      Partial search description derived so far.
  57      * @param object  $oPosition    Description of the token position within
  58                                     the query.
  59      *
  60      * @return SearchDescription[] List of derived search descriptions.
  61      */
  62     public function extendSearch($oSearch, $oPosition)
  63     {
  64         $aNewSearches = array();
  65
  66         // Partial token in Address.
  67         if (($oPosition->isPhrase('') || !$oPosition->isFirstPhrase())
  68             && $oSearch->hasName()
  69         ) {
  70             $iSearchCost = $this->bNumberToken ? 2 : 1;
  71             if ($this->iSearchNameCount >= CONST_Max_Word_Frequency) {
  72                 $iSearchCost += 1;
  73             }
  74
  75             $oNewSearch = $oSearch->clone($iSearchCost);
  76             $oNewSearch->addAddressToken(
  77                 $this->iId,
  78                 $this->iSearchNameCount < CONST_Max_Word_Frequency
  79             );
  80
  81             $aNewSearches[] = $oNewSearch;
  82         }
  83
  84         // Partial token in Name.
  85         if ((!$oSearch->hasPostcode() && !$oSearch->hasAddress())
  86             && (!$oSearch->hasName(true)
  87                 || $oSearch->getNamePhrase() == $oPosition->getPhrase())
  88         ) {
  89             $iSearchCost = 1;
  90             if (!$oSearch->hasName(true)) {
  91                 $iSearchCost += 1;
  92             }
  93             if ($this->bNumberToken) {
  94                 $iSearchCost += 1;
  95             }
  96
  97             $oNewSearch = $oSearch->clone($iSearchCost);
  98             $oNewSearch->addPartialNameToken(
  99                 $this->iId,
 100                 $this->iSearchNameCount < CONST_Max_Word_Frequency,
 101                 $this->iSearchNameCount > CONST_Search_NameOnlySearchFrequencyThreshold,
 102                 $oPosition->getPhrase()
 103             );
 104
 105             $aNewSearches[] = $oNewSearch;
 106         }
 107
 108         return $aNewSearches;
 109     }
 110
 111
 112     public function debugInfo()
 113     {
 114         return array(
 115                 'ID' => $this->iId,
 116                 'Type' => 'partial',
 117                 'Info' => array(
 118                            'count' => $this->iSearchNameCount
 119                           )
 120                );
 121     }
 122
 123     public function debugCode()
 124     {
 125         return 'w';
 126     }
 127 }