Chris@439: /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
Chris@439: 
Chris@439: /*
Chris@439:     Sonic Visualiser
Chris@439:     An audio file viewer and annotation editor.
Chris@439:     Centre for Digital Music, Queen Mary, University of London.
Chris@439:     This file copyright 2008 QMUL.
Chris@439:    
Chris@439:     This program is free software; you can redistribute it and/or
Chris@439:     modify it under the terms of the GNU General Public License as
Chris@439:     published by the Free Software Foundation; either version 2 of the
Chris@439:     License, or (at your option) any later version.  See the file
Chris@439:     COPYING included with this distribution for more information.
Chris@439: */
Chris@439: 
Chris@439: #ifndef _SIMPLE_SPARQL_QUERY_H_
Chris@439: #define _SIMPLE_SPARQL_QUERY_H_
Chris@439: 
Chris@724: #ifdef NOT_DEFINED
Chris@724: 
Chris@439: #include <QString>
Chris@439: #include <map>
Chris@439: #include <vector>
Chris@439: 
Chris@686: #include "base/Debug.h"
Chris@686: 
Chris@439: class ProgressReporter;
Chris@439: 
Chris@439: class SimpleSPARQLQuery
Chris@439: {
Chris@439: public:
Chris@439:     enum ValueType { NoValue, URIValue, LiteralValue, BlankValue };
Chris@439: 
Chris@439:     struct Value {
Chris@439:         Value() : type(NoValue), value() { }
Chris@439:         Value(ValueType t, QString v) : type(t), value(v) { }
Chris@439:         ValueType type;
Chris@439:         QString value;
Chris@439:     };
Chris@439: 
Chris@439:     typedef std::map<QString, Value> KeyValueMap;
Chris@439:     typedef std::vector<KeyValueMap> ResultList;
Chris@439: 
Chris@492:     /**
Chris@492:      * QueryType specifies the context in which the query will be
Chris@492:      * evaluated.  SimpleSPARQLQuery maintains a general global data
Chris@492:      * model, into which data can be loaded using addSourceToModel(),
Chris@492:      * as well as permitting one-time queries directly on data sources
Chris@492:      * identified by URL.
Chris@492:      *
Chris@492:      * The query type QueryFromModel indicates a query to be evaluated
Chris@492:      * over the general global model; the query type
Chris@492:      * QueryFromSingleSource indicates that the query should be
Chris@492:      * evaluated in the context of a model generated solely by parsing
Chris@492:      * the FROM url found in the query.
Chris@492:      *
Chris@492:      * Even in QueryFromSingleSource mode, the parsed data remains in
Chris@492:      * memory and will be reused in subsequent queries with the same
Chris@492:      * mode and FROM url.  To release data loaded in this way once all
Chris@492:      * queries across it are complete, pass the said FROM url to
Chris@492:      * closeSingleSource().
Chris@492:      */
Chris@489:     enum QueryType {
Chris@489:         QueryFromModel,
Chris@489:         QueryFromSingleSource
Chris@489:     };
Chris@489: 
Chris@492:     /**
Chris@492:      * Construct a query of the given type (indicating the data model
Chris@492:      * context for the query) using the given SPARQL query content.
Chris@492:      */
Chris@489:     SimpleSPARQLQuery(QueryType type, QString query);
Chris@439:     ~SimpleSPARQLQuery();
Chris@439: 
Chris@492:     /**
Chris@492:      * Add the given URI to the general global model used for
Chris@492:      * QueryFromModel queries.
Chris@492:      */
Chris@489:     static bool addSourceToModel(QString sourceUri);
Chris@489: 
Chris@492:     /**
Chris@492:      * Release any data that has been loaded from the given source as
Chris@492:      * part of a QueryFromSingleSource query with this source in the
Chris@492:      * FROM clause.  Note this will not prevent any subsequent queries
Chris@492:      * on the source from working -- it will just make them slower as
Chris@492:      * the data will need to be re-parsed.
Chris@492:      */
Chris@492:     static void closeSingleSource(QString sourceUri);
Chris@492: 
Chris@439:     void setProgressReporter(ProgressReporter *reporter);
Chris@439:     bool wasCancelled() const;
Chris@439:     
Chris@439:     ResultList execute();
Chris@439: 
Chris@439:     bool isOK() const;
Chris@439:     QString getErrorString() const;
Chris@439: 
Chris@492:     /**
Chris@492:      * Construct and execute a query, and return the first result
Chris@492:      * value for the given binding.
Chris@492:      */
Chris@489:     static Value singleResultQuery(QueryType type,
Chris@480:                                    QString query,
Chris@480:                                    QString binding);
Chris@480: 
Chris@439: protected:
Chris@439:     class Impl;
Chris@439:     Impl *m_impl;
Chris@589: 
Chris@589: private:
Chris@589:     SimpleSPARQLQuery(const SimpleSPARQLQuery &); // not provided
Chris@589:     SimpleSPARQLQuery &operator=(const SimpleSPARQLQuery &); // not provided
Chris@439: };
Chris@439: 
Chris@439: #endif
Chris@724: 
Chris@724: #endif