recoll/src/utils/hldata.h
2019-07-17 11:22:18 +02:00

136 lines
5.0 KiB
C++

/* Copyright (C) 2017-2019 J.F.Dockes
*
* License: GPL 2.1
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the
* Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#ifndef _hldata_h_included_
#define _hldata_h_included_
#include <vector>
#include <string>
#include <set>
#include <unordered_map>
/** Store data about user search terms and their expansions. This is used
* mostly for highlighting result text and walking the matches, generating
* spelling suggestions.
*/
struct HighlightData {
/** The user terms, excluding those with wildcards. This list is
* intended for orthographic suggestions so the terms are always
* lowercased, unaccented or not depending on the type of index
* (as the spelling dictionary is generated from the index terms).
*/
std::set<std::string> uterms;
/** The db query terms linked to the uterms entry they were expanded from.
* This is used for aggregating term stats when generating snippets (for
* choosing the best terms, allocating slots, etc. )
*/
std::unordered_map<std::string, std::string> terms;
/** The original user terms-or-groups. This is for display
* purposes: ie when creating a menu to look for a specific
* matched group inside a preview window. We want to show the
* user-entered data in the menu, not some transformation, so
* these are always raw, diacritics and case preserved.
*/
std::vector<std::vector<std::string> > ugroups;
/** Processed/expanded terms and groups. Used for looking for
* regions to highlight. A group can be a PHRASE or NEAR entry
* Terms are just groups with 1 entry. All
* terms are transformed to be compatible with index content
* (unaccented and lowercased as needed depending on
* configuration), and the list may include values
* expanded from the original terms by stem or wildcard expansion.
*/
struct TermGroup {
// We'd use an union but no can do
std::string term;
std::vector<std::vector<std::string> > orgroups;
int slack{0};
/* Index into ugroups. As a user term or group may generate
* many processed/expanded terms or groups, this is how we
* relate an expansion to its source (used, e.g. for
* generating anchors for walking search matches in the
* preview window). */
size_t grpsugidx{0};
enum TGK {TGK_TERM, TGK_NEAR, TGK_PHRASE};
TGK kind{TGK_TERM};
};
std::vector<TermGroup> index_term_groups;
void clear() {
uterms.clear();
ugroups.clear();
index_term_groups.clear();
}
void append(const HighlightData&);
// Print (debug)
std::string toString() const;
};
/* The following is used by plaintorich.cpp for finding zones to
highlight and by rclabsfromtext.cpp to choose fragments for the
abstract */
struct GroupMatchEntry {
// Start/End byte offsets in the document text
std::pair<int, int> offs;
// Index of the search group this comes from: this is to relate a
// match to the original user input.
size_t grpidx;
GroupMatchEntry(int sta, int sto, size_t idx)
: offs(sta, sto), grpidx(idx) {
}
};
// Find NEAR or PHRASE matches for one group of terms.
//
// @param hldata User query expansion descriptor (see above). We only use
// the index_term_groups entry
//
// @param grpidx Index in hldata.index_term_groups for the group we
// process. This is used by us to get the terms, group type
// (phrase/near) and slacks. We also set it in the output
// GroupMatchEntry structures to allow the caller to link a match
// with a specific user input (e.g. for walking the match in the
// GUI preview)
//
// @param inplists Position lists for the the group terms. This is the
// data used to look for matches.
//
// @param gpostobytes Translation of term position to start/end byte
// offsets. This is used to translate term positions to byte
// positions in the output, for ease of use by caller.
//
// @param[out] tboffs Found matches. Each match has a begin and end
// byte offset and an index linking to the origin data in the
// HighlightData structure.
extern bool matchGroup(
const HighlightData& hldata,
unsigned int grpidx,
const std::unordered_map<std::string, std::vector<int>>& inplists,
const std::unordered_map<int, std::pair<int,int>>& gpostobytes,
std::vector<GroupMatchEntry>& tboffs
);
#endif /* _hldata_h_included_ */