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test/source/blender/blenlib/BLI_string_search.hh
Campbell Barton b3dfde88f3 Cleanup: spelling in comments (check_spelling_* target)
Also uppercase acronyms: API, UTF & ASCII.
2025-05-17 10:17:37 +10:00

145 lines
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C++

/* SPDX-FileCopyrightText: 2023 Blender Authors
*
* SPDX-License-Identifier: GPL-2.0-or-later */
/** \file
* \ingroup bli
*/
#pragma once
#include "BLI_linear_allocator.hh"
#include "BLI_map.hh"
#include "BLI_span.hh"
#include "BLI_string_ref.hh"
#include "BLI_vector.hh"
namespace blender::string_search {
struct SearchItem {
void *user_data;
Span<StringRef> normalized_words;
/**
* When using menu-search, the search item is often split into multiple groups of words, each of
* which corresponds to a menu entry. This id is the same for words in the same group and
* different otherwise.
*/
Span<int> word_group_ids;
/**
* The id of the group that is highlighted in the UI. In some places, the words in this group are
* given higher weight.
*/
int main_group_id;
int main_group_length;
int total_length;
float weight;
/**
* This is a logical time stamp, i.e. the greater it is, the more recent the item was used. The
* number is not based on an actual clock.
*/
int recent_time;
/**
* Deprecated items can still be found via search, but are at the bottom of the list.
*/
bool is_deprecated;
};
struct RecentCache {
/**
* Stores a logical time stamp for each previously chosen search item. The higher the time
* stamp, the more recently the item has been selected.
*/
Map<std::string, int> logical_time_by_str;
};
/**
* Sometimes every search item has multiple parts. For example, when using menu search, each nested
* menu is a separate part. Usually, one of those parts is highlighted in the UI and should be
* prioritized in the search.
*/
enum class MainWordsHeuristic {
FirstGroup,
LastGroup,
All,
};
/**
* Non templated base class so that its methods can be implemented outside of this header.
*/
class StringSearchBase {
protected:
LinearAllocator<> allocator_;
Vector<SearchItem> items_;
const RecentCache *recent_cache_ = nullptr;
MainWordsHeuristic main_words_heuristic_;
void add_impl(StringRef str, void *user_data, float weight);
Vector<void *> query_impl(StringRef query) const;
};
/**
* #StringSearch filters and sorts search items based on a string query. Every search item has data
* of type T attached that is used to identify it.
*
* When querying, the a match score is computed between the query string and each item. Items that
* don't match are filtered out, the rest is sorted by the score. Elements with the same score are
* further sorted based on the optionally provided weight and other heuristics.
*
* The usage is simple. First #add all the search items and then use the #query method.
*/
template<typename T> class StringSearch : private StringSearchBase {
public:
StringSearch(const RecentCache *recent_cache, const MainWordsHeuristic main_words_heuristic)
{
recent_cache_ = recent_cache;
main_words_heuristic_ = main_words_heuristic;
}
/**
* Add a new possible result to the search.
*
* \param weight: Can be used to customize the order when multiple items have the same match
* score.
*/
void add(const StringRef str, T *user_data, const int weight = 0)
{
this->add_impl(str, (void *)user_data, weight);
}
/**
* Filter and sort all previously added search items.
* Returns an array containing the filtered user data.
*/
Vector<T *> query(const StringRef query) const
{
Vector<void *> result = this->query_impl(query);
Vector<T *> result_typed = result.as_span().cast<T *>();
return result_typed;
}
};
/**
* Computes the cost of transforming string a into b. The cost/distance is the minimal number of
* operations that need to be executed. Valid operations are deletion, insertion, substitution and
* transposition.
*
* This function is UTF8 aware in the sense that it works at the level of individual code points
* (1-4 bytes long) instead of on individual bytes.
*/
int damerau_levenshtein_distance(StringRef a, StringRef b);
/**
* Returns -1 when this is no reasonably good match.
* Otherwise returns the number of errors in the match.
*/
int get_fuzzy_match_errors(StringRef query, StringRef full);
/**
* Splits a string into words and normalizes them (currently that just means converting to lower
* case). The returned strings are allocated in the given allocator.
*/
void extract_normalized_words(StringRef str,
LinearAllocator<> &allocator,
Vector<StringRef, 64> &r_words,
Vector<int, 64> &r_word_group_ids);
} // namespace blender::string_search