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/** \file
 * \brief Literal analysis and scoring.
 */

#ifndef NG_LITERAL_ANALYSIS_H
#define NG_LITERAL_ANALYSIS_H

#include <set>
#include <vector>

#include "ng_holder.h"
#include "util/ue2string.h"

namespace ue2 {

#define NO_LITERAL_AT_EDGE_SCORE  10000000ULL
#define INVALID_EDGE_CAP         100000000ULL /* special-to-special score */

class NGHolder;

/**
 * Fetch the literal set for a given vertex, returning it in \p s. Note: does
 * NOT take into account any constraints due to streaming mode requirements.
 *
 * if only_first_encounter is requested, the output set may drop literals
 * generated by revisiting the destination vertex.
 */
std::set<ue2_literal> getLiteralSet(const NGHolder &g, const NFAVertex &v,
                                    bool only_first_encounter = true);
std::set<ue2_literal> getLiteralSet(const NGHolder &g, const NFAEdge &e);

/**
 * Returns true if we are unable to use a mixed sensitivity literal in rose (as
 * our literal matchers are generally either case sensitive or not).
 *
 * Shortish mixed sensitivity literals can be handled by confirm checks in rose
 * and are not flagged as bad.
 */
bool bad_mixed_sensitivity(const ue2_literal &s);

/**
 * Score all the edges in the given graph, returning them in \p scores indexed
 * by edge_index. */
std::vector<u64a> scoreEdges(const NGHolder &h,
                             const flat_set<NFAEdge> &known_bad = flat_set<NFAEdge>());

/** Returns a score for a literal set. Lower scores are better. */
u64a scoreSet(const std::set<ue2_literal> &s);

/** Compress a literal set to fewer literals. */
u64a compressAndScore(std::set<ue2_literal> &s);

/**
 * Compress a literal set to fewer literals and replace any long mixed
 * sensitivity literals with supported literals.
 */
u64a sanitizeAndCompressAndScore(std::set<ue2_literal> &s);

bool splitOffLeadingLiteral(const NGHolder &g, ue2_literal *lit_out,
                            NGHolder *rhs);

bool getTrailingLiteral(const NGHolder &g, ue2_literal *lit_out);

/** \brief Returns true if the given literal is the only thing in the graph,
 * from (start or startDs) to accept. */
bool literalIsWholeGraph(const NGHolder &g, const ue2_literal &lit);

} // namespace ue2

#endif
