xapian-core/api/msetinternal.h

   1 /** @file msetinternal.h
   2  * @brief Xapian::MSet internals
   3  */
   4 /* Copyright 2016,2017 Olly Betts
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License as
   8  * published by the Free Software Foundation; either version 2 of the
   9  * License, or (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  19  */
  20
  21 #ifndef XAPIAN_INCLUDED_MSETINTERNAL_H
  22 #define XAPIAN_INCLUDED_MSETINTERNAL_H
  23
  24 #include "enquireinternal.h"
  25 #include "net/serialise.h"
  26 #include "result.h"
  27 #include "weight/weightinternal.h"
  28
  29 #include "xapian/intrusive_ptr.h"
  30 #include "xapian/mset.h"
  31 #include "xapian/types.h"
  32
  33 #include <memory>
  34 #include <string>
  35 #include <unordered_map>
  36 #include <vector>
  37
  38 class Matcher;
  39
  40 namespace Xapian {
  41
  42 /// Xapian::MSet internals.
  43 class MSet::Internal : public Xapian::Internal::intrusive_base {
  44     friend class MSet;
  45     friend class MSetIterator;
  46     friend class ::Matcher;
  47
  48     /// Don't allow assignment.
  49     void operator=(const Internal &) = delete;
  50
  51     /// Don't allow copying.
  52     Internal(const Internal &) = delete;
  53
  54     /// Relevance weights for non-query terms for generating snippets.
  55     mutable std::unordered_map<std::string, double> snippet_bg_relevance;
  56
  57     /// The items in the MSet.
  58     std::vector<Result> items;
  59
  60     /// For looking up query term frequencies and weights.
  61     std::unique_ptr<Xapian::Weight::Internal> stats;
  62
  63     Xapian::Internal::intrusive_ptr<const Enquire::Internal> enquire;
  64
  65     Xapian::doccount matches_lower_bound = 0;
  66
  67     Xapian::doccount matches_estimated = 0;
  68
  69     Xapian::doccount matches_upper_bound = 0;
  70
  71     Xapian::doccount uncollapsed_lower_bound = 0;
  72
  73     Xapian::doccount uncollapsed_estimated = 0;
  74
  75     Xapian::doccount uncollapsed_upper_bound = 0;
  76
  77     Xapian::doccount first = 0;
  78
  79     double max_possible = 0;
  80
  81     double max_attained = 0;
  82
  83     /// Scale factor to convert weights to percentages.
  84     double percent_scale_factor = 0;
  85
  86   public:
  87     Internal() {}
  88
  89     Internal(Xapian::doccount first_,
  90              Xapian::doccount matches_upper_bound_,
  91              Xapian::doccount matches_lower_bound_,
  92              Xapian::doccount matches_estimated_,
  93              Xapian::doccount uncollapsed_upper_bound_,
  94              Xapian::doccount uncollapsed_lower_bound_,
  95              Xapian::doccount uncollapsed_estimated_,
  96              double max_possible_,
  97              double max_attained_,
  98              std::vector<Result>&& items_,
  99              double percent_scale_factor_)
 100         : items(std::move(items_)),
 101           matches_lower_bound(matches_lower_bound_),
 102           matches_estimated(matches_estimated_),
 103           matches_upper_bound(matches_upper_bound_),
 104           uncollapsed_lower_bound(uncollapsed_lower_bound_),
 105           uncollapsed_estimated(uncollapsed_estimated_),
 106           uncollapsed_upper_bound(uncollapsed_upper_bound_),
 107           first(first_),
 108           max_possible(max_possible_),
 109           max_attained(max_attained_),
 110           percent_scale_factor(percent_scale_factor_) {}
 111
 112     void set_first(Xapian::doccount first_) { first = first_; }
 113
 114     void set_enquire(const Xapian::Enquire::Internal* enquire_) {
 115         enquire = enquire_;
 116     }
 117
 118     Xapian::Weight::Internal* get_stats() const { return stats.get(); }
 119
 120     void set_stats(Xapian::Weight::Internal* stats_) { stats.reset(stats_); }
 121
 122     double get_percent_scale_factor() const { return percent_scale_factor; }
 123
 124     Xapian::Document get_document(Xapian::doccount index) const;
 125
 126     void fetch(Xapian::doccount first, Xapian::doccount last) const;
 127
 128     void set_item_weight(Xapian::doccount i, double weight);
 129
 130     int convert_to_percent(double weight) const;
 131
 132     void unshard_docids(Xapian::doccount shard, Xapian::doccount n_shards);
 133
 134     void merge_stats(const Internal* o);
 135
 136     std::string snippet(const std::string & text, size_t length,
 137                         const Xapian::Stem & stemmer,
 138                         unsigned flags,
 139                         const std::string & hi_start,
 140                         const std::string & hi_end,
 141                         const std::string & omit) const;
 142
 143     /** Serialise this object.
 144      *
 145      *  @return         The serialisation of this object.
 146      */
 147     std::string serialise() const;
 148
 149     /** Unserialise a serialised Xapian::MSet::Internal object.
 150      *
 151      *  @param p        Pointer to the start of the string to unserialise.
 152      *  @param p_end    Pointer to the end of the string to unserialise.
 153      *
 154      *  This object is updated with the unserialised data.
 155      */
 156     void unserialise(const char * p, const char * p_end);
 157
 158     /// Return a string describing this object.
 159     std::string get_description() const;
 160 };
 161
 162 }
 163
 164 #endif // XAPIAN_INCLUDED_MSETINTERNAL_H