/* Copyright (C) 2008 J.F.Dockes
* 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 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the
* Free Software Foundation, Inc.,
* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#ifndef _rclquery_h_included_
#define _rclquery_h_included_
#include <string>
#include <vector>
#include "refcntr.h"
#include "searchdata.h"
#ifndef NO_NAMESPACES
namespace Rcl {
#endif
class Db;
class Doc;
enum abstract_result {
ABSRES_ERROR = 0,
ABSRES_OK = 1,
ABSRES_TRUNC = 2
};
// Snippet entry for makeDocAbstract
class Snippet {
public:
Snippet(int page, const std::string& snip)
: page(page), snippet(snip)
{
}
Snippet& setTerm(const std::string& trm)
{
term = trm;
return *this;
}
int page;
std::string term;
std::string snippet;
};
/**
* An Rcl::Query is a question (SearchData) applied to a
* database. Handles access to the results. Somewhat equivalent to a
* cursor in an rdb.
*
*/
class Query {
public:
/** The constructor only allocates memory */
Query(Db *db);
~Query();
/** Get explanation about last error */
std::string getReason() const;
/** Choose sort order. Must be called before setQuery */
void setSortBy(const std::string& fld, bool ascending = true);
const std::string& getSortBy() const {return m_sortField;}
bool getSortAscending() const {return m_sortAscending;}
/** Return or filter results with identical content checksum */
void setCollapseDuplicates(bool on) {m_collapseDuplicates = on;}
/** Accept data describing the search and query the index. This can
* be called repeatedly on the same object which gets reinitialized each
* time.
*/
bool setQuery(RefCntr<SearchData> q);
/** Get results count for current query */
int getResCnt();
/** Get document at rank i in current query results. */
bool getDoc(int i, Doc &doc);
/** Get possibly expanded list of query terms */
bool getQueryTerms(std::vector<std::string>& terms);
/** Return a list of terms which matched for a specific result document */
bool getMatchTerms(const Doc& doc, std::vector<std::string>& terms);
bool getMatchTerms(unsigned long xdocid, std::vector<std::string>& terms);
/** Build synthetic abstract for document, extracting chunks relevant for
* the input query. This uses index data only (no access to the file) */
// Abstract return as one string
bool makeDocAbstract(Doc &doc, std::string& abstract);
// Returned as a snippets vector
bool makeDocAbstract(Doc &doc, std::vector<std::string>& abstract);
// Returned as a vector of pair<page,snippet> page is 0 if unknown
abstract_result makeDocAbstract(Doc &doc, std::vector<Snippet>& abst,
int maxoccs= -1, int ctxwords = -1);
/** Retrieve detected page breaks positions */
int getFirstMatchPage(Doc &doc, std::string& term);
/** Expand query to look for documents like the one passed in */
std::vector<std::string> expand(const Doc &doc);
/** Return the Db we're set for */
Db *whatDb();
/* make this public for access from embedded Db::Native */
class Native;
Native *m_nq;
private:
std::string m_reason; // Error explanation
Db *m_db;
void *m_sorter;
std::string m_sortField;
bool m_sortAscending;
bool m_collapseDuplicates;
int m_resCnt;
RefCntr<SearchData> m_sd;
/* Copyconst and assignement private and forbidden */
Query(const Query &) {}
Query & operator=(const Query &) {return *this;};
};
#ifndef NO_NAMESPACES
}
#endif // NO_NAMESPACES
#endif /* _rclquery_h_included_ */