godot/core/string/fuzzy_search.h

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/*  fuzzy_search.h                                                        */
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#ifndef FUZZY_SEARCH_H
#define FUZZY_SEARCH_H

#include "core/variant/variant.h"

class FuzzyTokenMatch;

struct FuzzySearchToken {
	int idx = -1;
	String string;

	bool try_exact_match(FuzzyTokenMatch &p_match, const String &p_target, int p_offset) const;
	bool try_fuzzy_match(FuzzyTokenMatch &p_match, const String &p_target, int p_offset, int p_miss_budget) const;
};

class FuzzyTokenMatch {
	friend struct FuzzySearchToken;
	friend class FuzzySearchResult;
	friend class FuzzySearch;

	int matched_length = 0;
	int token_length = 0;
	int token_idx = -1;
	Vector2i interval = Vector2i(-1, -1); // x and y are both inclusive indices.

	void add_substring(int p_substring_start, int p_substring_length);
	bool intersects(const Vector2i &p_other_interval) const;
	bool is_case_insensitive(const String &p_original, const String &p_adjusted) const;
	int get_miss_count() const { return token_length - matched_length; }

public:
	int score = 0;
	Vector<Vector2i> substrings; // x is start index, y is length.
};

class FuzzySearchResult {
	friend class FuzzySearch;

	int miss_budget = 0;
	Vector2i match_interval = Vector2i(-1, -1);

	bool can_add_token_match(const FuzzyTokenMatch &p_match) const;
	void score_token_match(FuzzyTokenMatch &p_match, bool p_case_insensitive) const;
	void add_token_match(const FuzzyTokenMatch &p_match);
	void maybe_apply_score_bonus();

public:
	String target;
	int score = 0;
	int dir_index = -1;
	Vector<FuzzyTokenMatch> token_matches;
};

class FuzzySearch {
	Vector<FuzzySearchToken> tokens;

	void sort_and_filter(Vector<FuzzySearchResult> &p_results) const;

public:
	int start_offset = 0;
	bool case_sensitive = false;
	int max_results = 100;
	int max_misses = 2;
	bool allow_subsequences = true;

	void set_query(const String &p_query);
	bool search(const String &p_target, FuzzySearchResult &p_result) const;
	void search_all(const PackedStringArray &p_targets, Vector<FuzzySearchResult> &p_results) const;
};

#endif // FUZZY_SEARCH_H