/*=============================================================================
 * parser for CSP instances represented in XCSP3 Format
 * 
 * Copyright (c) 2015 xcsp.org (contact <at> xcsp.org)
 * Copyright (c) 2008 Olivier ROUSSEL (olivier.roussel <at> cril.univ-artois.fr)
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *=============================================================================
 */
#ifndef _XMLParser_h_
#define _XMLParser_h_

/**
 * @file XMLParser.h
 * @brief defines the XMLParser class to parse a CSP instance in XML format
 */



#include <iostream>
#include <fstream>
#include <string>
#include <map>
#include <deque>
#include <vector>
#include <sstream>
#include <stdexcept>
#include <cassert>
#include <cstring>

#include "XCSP3Constants.h"
#include "XCSP3Domain.h"
#include "XCSP3Variable.h"
#include "XCSP3Constraint.h"
#include "XCSP3utils.h"
#include "XCSP3Objective.h"
#include "XCSP3Manager.h"

#include "UTF8String.h"
#include "AttributeList.h"

/**
 * @namespace CSPXMLParser
 * @brief this namespace encloses all definitions relative to the
 * CSP XML format parser.
 */
namespace XCSP3Core {

    using namespace std;


    /**
     * @brief contains a parser for the CSP XML format.
     *
     * This class proposes a parser in SAX mode (to use less memory than
     * in DOM mode)
     *
     *
     */
    class XMLParser {
    public:
        // list of attributes and values for a tag
        map<string, XEntity *> variablesList;
        vector<XDomainInteger *> allDomains;
        vector<XConstraint *> constraints;
        XCSP3Manager *manager;


        // stack of operands to construct list, dictionaries, predicate
        // parameters and so on

    private:


        /***************************************************************************
         * @brief the action to be performed (callback) when a tag is read in the
         * XML file
         ***************************************************************************/
        class TagAction {
        protected:
            bool activated;
            XMLParser *parser;
            string tagName;

        public:
            TagAction(XMLParser *parser, string name) : parser(parser), tagName(name) { activated = false; }


            virtual ~TagAction() { }


            void activate() { activated = true; }


            void deactivate() { activated = false; }


            bool isActivated() { return activated; }


            /**
             * return the name of this tag (constant)
             */
            const char *getTagName() { return tagName.c_str(); }


            // AttributeList &attributes
            virtual void beginTag(const AttributeList &) { }


            /**
             *
             * @parm last must be true if this is the last chunk of text
             */
            // UTF8String txt, bool last
            virtual void text(const UTF8String txt, bool) {
                if(!txt.isWhiteSpace())
                    throw runtime_error("<" + tagName + "> tag should not have meaningful text");
            }


            virtual void endTag() { }


        protected :
            /**
             * check that the parent tag in the XML file has the indicated name
             *
             * when name is NULL, check that this tag has no parent in the XML file
             *
             * @param parentTag: the expected name of the parent tag or NULL to
             * check that we have no parent
             * @param n: 1 for parent, 2 for grand-parent and so on
             */
            void checkParentTag(const char *parentTag, int n = 1) {
                if(this->parser->getParentTagAction(n) == NULL) {
                    if(parentTag != NULL)
                        throw runtime_error("tag has no parent but it should have one");
                    else
                        return;
                }

                if(parentTag == NULL)
                    throw runtime_error("tag should have no parent");

#ifdef debug
                cout << "parent tag="
                     << this->parser->getParentTagAction(n)->getTagName() << endl;
#endif
                if(strcmp(this->parser->getParentTagAction(n)->getTagName(),
                          parentTag) != 0)
                    throw runtime_error("wrong parent for tag");
            }

        };

        typedef map<UTF8String, TagAction *> TagActionList;

        TagActionList tagList;

        struct State {
            bool subtagAllowed;


            State() {
                subtagAllowed = true;

            }

        };

        class ListTagAction;

        // the top of the following stacks is at the FRONT
        deque<TagAction *> actionStack;
        deque<State> stateStack;
        vector<vector<XVariable *> > lists;   // used to store Many lists of variables (usefull with lex, channel....)
        vector<vector<XVariable *> > matrix;      // Used in case of matrix tag
        vector<vector<int> > patterns;

        vector<XVariable *> args;   // used to store a list of args
        vector<XVariable *> values; // used to store a list of variables
        vector<XVariable *> occurs;   // used in cardinality

        vector<int> integers;  // used to store a list of coefficients

        vector<XVariable *> origins;   // used to store a origins in noOverlap/cumulative Constraint
        vector<XVariable *> lengths;   // used to store lengths in noOverlap/cumulative Constraint
        vector<XVariable *> ends;   // used to store a origins in cumulative Constraint
        vector<XVariable *> heights;   // used to store a origins in cumulative Constraint
        vector<XIntegerEntity *> widths;   // used to store lengths in stretch constraint

        vector<int> currentTuple;
        ListTagAction *listTag;       // The List tag action call

        string classes;

        bool zeroIgnored;          // for nooverlap
        string condition;          // used to store a condition in prefix form
        bool star;                 // true if the extension contain star in tuples
        int startIndex, startIndex2;            // used in some list tag
        XVariable *index;          // used with tag index
        RankType rank;             // used with rank tag
        OrderType op;
        string expr;
        string start, final;        // used in regular constraint
        vector<XTransition> transitions; // used in regular and mdd constraints
        int nbParameters;
        bool closed;
        vector<XEntity *> toFree;
        vector<XIntegerEntity *> toFreeEntity;

        bool keepIntervals;

        void registerTagAction(TagActionList &tagList, TagAction *action) {
            tagList[action->getTagName()] = action;
        }


        /**
         *
         */



        /**
         * Parse a sequence of tokens. Each token can represent a compact list of array variables, or a basic entity, or a template parameter
         */

        void parseSequence(const UTF8String &txt, vector<XVariable *> &list, vector<char> delimiters = vector<char>());


        void parseDomain(const UTF8String &txt, XDomainInteger &domain);


        void parseListOfIntegerOrInterval(const UTF8String &txt, vector<XIntegerEntity *> &listToFill);


        bool parseTuples(const UTF8String &txt, vector<vector<int> > &tuples);


            /***************************************************************************
             * a handler to silently ignore unkown tags
             ***************************************************************************/
        class UnknownTagAction : public TagAction {
        public:
            UnknownTagAction(XMLParser *parser, string name) : TagAction(parser, name) { }


            // AttributeList &attributes
            virtual void beginTag(const AttributeList &) {
                throw runtime_error("Unknown Tag");
            }

        };

        /***************************************************************************
         * Actions performed on INSTANCE tag
         ***************************************************************************/

        class InstanceTagAction : public TagAction {
        public:
            InstanceTagAction(XMLParser *parser, string name) : TagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void endTag() override;
        };

        /***************************************************************************
         * Actions performed on VARIABLES tag
         ***************************************************************************/
        class VariablesTagAction : public TagAction {
        public:
            VariablesTagAction(XMLParser *parser, string name) : TagAction(parser, name) { }
            virtual void beginTag(const AttributeList &attributes) override;
            virtual void endTag() override;
        };


        /***************************************************************************
         * Actions performed on VAR tag
         ***************************************************************************/

        class VarTagAction : public TagAction {
        private:
            XVariable *variable;
            XVariableArray *variableArray;
            XDomainInteger *domain;
            string id, classes;

        public:
            VarTagAction(XMLParser *parser, string name) : TagAction(parser, name), variable(NULL), variableArray(NULL), domain(NULL) { }
            void beginTag(const AttributeList &attributes) override;
            void text(const UTF8String txt, bool last) override ;
            void endTag() override;
        };

        /***************************************************************************
         * Actions performed on ARRAY tag
         ***************************************************************************/

        class ArrayTagAction : public TagAction {

        public:
            XVariableArray *varArray;
            XDomainInteger *domain;
            string id, classes;
            vector<int> sizes;


            ArrayTagAction(XMLParser *parser, string name) : TagAction(parser, name), varArray(NULL), domain(NULL) { }


            void beginTag(const AttributeList &attributes) override;
            void endTag() override ;


            // UTF8String txt, bool last
            void text(const UTF8String txt, bool) override {
                this->parser->parseDomain(txt, *domain);
            }
        };

        class DomainTagAction : public TagAction {

        public:
            XDomainInteger *d;
            string forAttr;


            DomainTagAction(XMLParser *parser, string name) : TagAction(parser, name) { }


            void beginTag(const AttributeList &attributes) override;
            void text(const UTF8String txt, bool last)  override;
            void endTag() override;
        };


        /***************************************************************************
         * Actions performed on CONSTRAINTS tag
         ***************************************************************************/

        class ConstraintsTagAction : public TagAction {

        public:
            ConstraintsTagAction(XMLParser *parser, string name) : TagAction(parser, name) { }


            // AttributeList &attributes
            virtual void beginTag(const AttributeList &) {
                this->checkParentTag("instance");
                this->parser->manager->beginConstraints();
            }


            virtual void endTag() {
                this->parser->manager->endConstraints();
            }
        };


        /***************************************************************************
         * All constraint MUST inherit this tagAction
         *****************************************************************************/

        class BasicConstraintTagAction : public TagAction {
        public :
            XConstraintGroup *group;
            string id;
            BasicConstraintTagAction(XMLParser *parser, string name) : TagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
        };

        /***************************************************************************
         * Actions performed on EXTENSION tag
         ****************************************************************************/

        class ExtensionTagAction : public BasicConstraintTagAction {
        public:
            XConstraintExtension *constraint;
            ExtensionTagAction(XMLParser *parser, string name) : BasicConstraintTagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void endTag() override;
        };

        /***************************************************************************
         * Actions performed on INTENSION tag
         ****************************************************************************/
        class IntensionTagAction : public BasicConstraintTagAction {
        protected :
            UTF8String fnc;
        public:
            XConstraintIntension *constraint;
            IntensionTagAction(XMLParser *parser, string name) : BasicConstraintTagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void text(const UTF8String txt, bool last) override;
            void endTag() override;
        };


        /***************************************************************************
        ****************************************************************************
         *                  CONSTRAINTS DEFINED ON LANGAGES
         ***************************************************************************
        ***************************************************************************/

        /***************************************************************************
        * Actions performed on REGULAR tag
        ****************************************************************************/

        class RegularTagAction : public BasicConstraintTagAction {
        public:
            XConstraintRegular *constraint;
            RegularTagAction(XMLParser *parser, string name) : BasicConstraintTagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void endTag() override;
       };

        /***************************************************************************
         * Actions performed on MDD tag
         ****************************************************************************/

        class MDDTagAction : public BasicConstraintTagAction {
        public:
            XConstraintMDD *constraint;
            MDDTagAction(XMLParser *parser, string name) : BasicConstraintTagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void endTag() override;


        };


        /***************************************************************************
        ****************************************************************************
         *                  CONSTRAINTS DEFINED ON COMPARISON
        ****************************************************************************
        ***************************************************************************/


        /***************************************************************************
         * Actions performed on ALLDIFF tag / ALLEQUAL
         ****************************************************************************/

        class AllDiffEqualTagAction : public BasicConstraintTagAction {

        public:
            XConstraintAllDiff *alldiff;
            XConstraintAllEqual *allequal;
            XConstraint *ct;
            AllDiffEqualTagAction(XMLParser *parser, string tag) : BasicConstraintTagAction(parser, tag) { }
            void beginTag(const AttributeList &attributes) override;
            void text(const UTF8String txt, bool last) override;
            void endTag() override;
        };

        /***************************************************************************
         * Actions performed on ORDERED tag
         ****************************************************************************/
        class OrderedTagAction : public BasicConstraintTagAction {
        public:
            XConstraintOrdered *constraint;
            OrderedTagAction(XMLParser *parser, string name) : BasicConstraintTagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void text(const UTF8String txt, bool last) override;
            void endTag() override;
        };

        /***************************************************************************
         * Actions performed on LEX tag
         ****************************************************************************/
        class LexTagAction : public BasicConstraintTagAction {
        public:
            XConstraintLex *constraint;
            LexTagAction(XMLParser *parser, string name) : BasicConstraintTagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void endTag() override;
        };


        /***************************************************************************
        ****************************************************************************
         *                  COUNTIG AND SUMMING CONSTRAINTS
        ****************************************************************************
         ****************************************************************************/

        /***************************************************************************
         * Actions performed on SUM tag
         ****************************************************************************/


        class SumTagAction : public BasicConstraintTagAction {
        public:
            XConstraintSum *constraint;
            SumTagAction(XMLParser *parser, string name) : BasicConstraintTagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void endTag() override;
        };

        /***************************************************************************
         * Actions performed on NVALUES tag
         ****************************************************************************/
        class NValuesTagAction : public BasicConstraintTagAction {
        public:
            XConstraintNValues *constraint;
            NValuesTagAction(XMLParser *parser, string name) : BasicConstraintTagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void endTag() override;
        };

        /***************************************************************************
         * Actions performed on COUNT tag
         ****************************************************************************/

        class CountTagAction : public BasicConstraintTagAction {
        public:
            XConstraintCount *constraint;
            CountTagAction(XMLParser *parser, string name) : BasicConstraintTagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void endTag() override;
        };

        /***************************************************************************
        * Actions performed on CARDINALITY tag
        ****************************************************************************/

        class CardinalityTagAction : public BasicConstraintTagAction {
        public:
            XConstraintCardinality *constraint;
            CardinalityTagAction(XMLParser *parser, string name) : BasicConstraintTagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void endTag() override;
        };


        /***************************************************************************
        ****************************************************************************
         *                  CONNECTION CONSTRAINTS
        ****************************************************************************
         ****************************************************************************/

        /***************************************************************************
         * Actions performed on CHANNEL tag
         ****************************************************************************/
        class ChannelTagAction : public BasicConstraintTagAction {
        public:
            XConstraintChannel *constraint;
            ChannelTagAction(XMLParser *parser, string name) : BasicConstraintTagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void text(const UTF8String txt, bool last) override;
            void endTag() override;
        };

        /***************************************************************************
         * Actions performed on ELEMENT tag
         ****************************************************************************/

        class ElementTagAction : public BasicConstraintTagAction {
        public:
            XConstraintElement *constraint;
            ElementTagAction(XMLParser *parser, string name) : BasicConstraintTagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void endTag() override;
        };

        /***************************************************************************
         * Actions performed on MAXIMUM or MINIMUM tag
         ****************************************************************************/


        class MinMaxTagAction : public BasicConstraintTagAction {

        public:
            XConstraintMaximum *constraint;
            MinMaxTagAction(XMLParser *parser, string tag) : BasicConstraintTagAction(parser, tag) { }
            void beginTag(const AttributeList &attributes) override;
            void endTag() override;
        };


        /***************************************************************************
         ****************************************************************************
          *                  PACKING and SCHEDULING CONSTRAINTS
         ****************************************************************************
          ****************************************************************************/

        /***************************************************************************
         * Actions performed on STRETCH tag
         ****************************************************************************/


        class StretchTagAction : public BasicConstraintTagAction {
        public:
            XConstraintStretch *constraint;
            StretchTagAction(XMLParser *parser, string name) : BasicConstraintTagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void endTag() override;
        };


        /***************************************************************************
         * Actions performed on NOOVERLAP tag
         ****************************************************************************/

        class NoOverlapTagAction : public BasicConstraintTagAction {
        public:
            bool diffn;
            XConstraintNoOverlap *constraint;
            NoOverlapTagAction(XMLParser *parser, string name) : BasicConstraintTagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void endTag() override;
        };

        /***************************************************************************
           * Actions performed on CUMULATIVE tag
           ****************************************************************************/

        class CumulativeTagAction : public BasicConstraintTagAction {
        public:
            XConstraintCumulative *constraint;
            CumulativeTagAction(XMLParser *parser, string name) : BasicConstraintTagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void endTag() override;
        };


        /***************************************************************************
         ****************************************************************************
          *                            OBJECTIVES
         ****************************************************************************
          ****************************************************************************/

        class ObjectivesTagAction : public TagAction {
        public:
            XObjective *objective;
            ObjectivesTagAction(XMLParser *parser, string name) : TagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void endTag() override;
        };


        class MinimizeOrMaximizeTagAction : public TagAction {
        public:
            MinimizeOrMaximizeTagAction(XMLParser *parser, string name) : TagAction(parser, name) { }
            XObjective *obj;
            void beginTag(const AttributeList &attributes) override;
            void text(const UTF8String txt, bool last) override;
        };

        /***************************************************************************
         * Actions performed on instantiation tag
         ****************************************************************************/
        class InstantiationTagAction : public BasicConstraintTagAction {
        public:
            InstantiationTagAction(XMLParser *parser, string name) : BasicConstraintTagAction(parser, name) { }
            XConstraintInstantiation *constraint;
            void beginTag(const AttributeList &attributes) override;
            void endTag() override;
        };


        /***************************************************************************
         * Actions performed on LIST tag
         ****************************************************************************/

        class ListTagAction : public TagAction {
        public:
            int nbCallsToList;
            // The first call stores datas inside this->parser->list
            // the ith call (i>1) stores datas inside this->parser->manyLists[i-1];
            ListTagAction(XMLParser *parser, string name) : TagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void text(const UTF8String txt, bool last) override;
            void endTag() override;
        };




        /***************************************************************************
         * Actions performed on SUPPORTS CONFLICTS tag
         ****************************************************************************/

        class ConflictOrSupportTagAction : public TagAction {
        protected :
        public:
            ConflictOrSupportTagAction(XMLParser *parser, string name) : TagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void text(const UTF8String txt, bool last) override;
        };


        /***************************************************************************
         * Actions performed on COEFFS tag
         ****************************************************************************/

        class ConditionTagAction : public TagAction {
        public:
            ConditionTagAction(XMLParser *parser, string name) : TagAction(parser, name) { }


            // UTF8String txt, bool last
            virtual void text(const UTF8String txt, bool) {
                this->parser->condition += txt.to(this->parser->condition);
            }


            virtual void endTag() {
                this->parser->condition = trim(this->parser->condition);
            }
        };


        /***************************************************************************
         * Actions performed on CONDITION tag
         ****************************************************************************/

        class ListOfIntegerTagAction : public TagAction {
        public:
            ListOfIntegerTagAction(XMLParser *parser, string name) : TagAction(parser, name) { }
            virtual void text(const UTF8String txt, bool last) override;
        };


        /***************************************************************************
         * Actions performed on VALUES / VALUE tag
         ****************************************************************************/

        class ListOfVariablesOrIntegerTagAction : public TagAction {

            vector<XVariable *> &listToFill;
        public:
            ListOfVariablesOrIntegerTagAction(XMLParser *parser, string nm, vector<XVariable *> &ltf) : TagAction(parser, nm), listToFill(ltf) { }
            virtual void beginTag(const AttributeList &attributes) override;
            virtual void text(const UTF8String txt, bool last) override;
        };


        class ListOfVariablesOrIntegerOrIntervalTagAction : public TagAction {

            vector<XVariable *> &listToFill;
        public:
            ListOfVariablesOrIntegerOrIntervalTagAction(XMLParser *parser, string nm, vector<XVariable *> &ltf) : TagAction(parser, nm), listToFill(ltf) { }
            virtual void beginTag(const AttributeList &attributes) override;
            virtual void text(const UTF8String txt, bool last) override;
        };

        /***************************************************************************
          * Actions performed on  ORIGINS tag
          ****************************************************************************/

        class OriginsTagAction : public TagAction {

            vector<XVariable *> &listToFill;
        public:
            OriginsTagAction(XMLParser *parser, string nm, vector<XVariable *> &ltf) : TagAction(parser, nm), listToFill(ltf) { }
            virtual void beginTag(const AttributeList &attributes) override;
            virtual void text(const UTF8String txt, bool last) override;
        };

        /***************************************************************************
          * Actions performed on  WIDTH tag
          ****************************************************************************/

        class ListOfIntegerOrIntervalTagAction : public TagAction {

            vector<XIntegerEntity *> &listToFill;
        public:
            ListOfIntegerOrIntervalTagAction(XMLParser *parser, string nm,
                                             vector<XIntegerEntity *> &ltf) : TagAction(parser, nm), listToFill(ltf) { }
            virtual void beginTag(const AttributeList &attributes) override;
            virtual void text(const UTF8String txt, bool last) override;
        };


        /***************************************************************************
         * Actions performed on GROUP tag
         ****************************************************************************/

        class GroupTagAction : public TagAction {
        public:
            XConstraintGroup *group;
            GroupTagAction(XMLParser *parser, string name) : TagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void endTag() override;
        };

        /***************************************************************************
         * Actions performed on SLIDE tag
         ****************************************************************************/

        class SlideTagAction : public TagAction {
        public:
            XConstraintGroup *group;
            vector<XVariable *> list;

            int offset = 1;
            bool circular = false;


            SlideTagAction(XMLParser *parser, string name) : TagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void endTag() override;
        };

        /***************************************************************************
         * Actions performed on GROUP tag
         ****************************************************************************/
        class BlockTagAction : public TagAction {
        public:
            BlockTagAction(XMLParser *parser, string name) : TagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void endTag() override;
        };


        /***************************************************************************
         * Actions performed on ARGS tag
         ****************************************************************************/

        class ArgsTagAction : public TagAction {
        public:
            ArgsTagAction(XMLParser *parser, string name) : TagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            virtual void text(const UTF8String txt, bool last) override;
            void endTag() override;
        };


        /***************************************************************************
         * Actions performed on Operator tag
         ****************************************************************************/

        class OperatorTagAction : public TagAction {
        public:
            OperatorTagAction(XMLParser *parser, string name) : TagAction(parser, name) { }
            void text(const UTF8String txt, bool last) override;
        };


        /***************************************************************************
         * Actions performed on INDEX tag
         ****************************************************************************/
        class IndexTagAction : public TagAction {
        public:
            IndexTagAction(XMLParser *parser, string name) : TagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void text(const UTF8String txt, bool last) override;
        };

        /***************************************************************************
         * Actions performed on MATRIX TAG
         ****************************************************************************/

        class MatrixTagAction : public TagAction {
        public:
            MatrixTagAction(XMLParser *parser, string name) : TagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void text(const UTF8String txt, bool last) override;
            void endTag() override;
        };


        /***************************************************************************
         * Actions performed on START or FINAL tag
         ****************************************************************************/

        class StringTagAction : public TagAction {
        public:
            StringTagAction(XMLParser *parser, string name) : TagAction(parser, name) { }
            void text(const UTF8String txt, bool last) override;
        };


        /***************************************************************************
         * Actions performed on  TRANSITIONS tag
         ****************************************************************************/

        class TransitionsTagAction : public TagAction {
        public:
            int nb, val;
            std::string from, to;
            TransitionsTagAction(XMLParser *parser, string name) : TagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void text(const UTF8String txt, bool last) override;
        };


        /***************************************************************************
         * Actions performed on  TRANSITIONS tag
        ****************************************************************************/


        class PatternsTagAction : public TagAction {
        public:
            vector<XVariable *> listToFill;
            PatternsTagAction(XMLParser *parser, string name) : TagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void text(const UTF8String txt, bool last) override;
        };


        class CircuitTagAction : public BasicConstraintTagAction {
            XConstraintCircuit *constraint;
        public :
            CircuitTagAction(XMLParser *parser, string name) : BasicConstraintTagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void text(const UTF8String txt, bool last) override;
            void endTag() override;
        };


        /***************************************************************************
         * Actions performed on  ANNOTATIONS TAG
        ****************************************************************************/

        class AnnotationsTagAction : public TagAction {
        public:
            AnnotationsTagAction(XMLParser *parser, string name) : TagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void endTag() override;
        };


        class DecisionTagAction : public TagAction {
            vector<XVariable *> list;
        public:
            DecisionTagAction(XMLParser *parser, string name) : TagAction(parser, name) { }
            void beginTag(const AttributeList &attributes) override;
            void text(const UTF8String txt, bool last) override;
            void endTag() override;
        };


    public:
        XMLParser(XCSP3CoreCallbacks *cb);
        ~XMLParser();

        /**
         * get the parent tag action that is n levels higher in the current
         * branch of the XML parse tree
         */
        TagAction *getParentTagAction(int n = 1) {
            if(n < 0 || n >= (int) actionStack.size())
                return NULL;

            return actionStack[n];
        }


        /**
         * callbacks from the XML parser
         */
        void startDocument() {
            clearStacks();
        }


        void endDocument() { }


        void startElement(UTF8String name, const AttributeList &attributes);


        void endElement(UTF8String name);


        void characters(UTF8String chars);


        void handleAbridgedNotation(UTF8String chars, bool lastChunk);



    protected:
        void clearStacks() {
            stateStack.clear();
        }

        // text which is left for the next call to characters() because it
        // may not be a complete token
        UTF8String textLeft;

        // specific actions
        VarTagAction *varTagAction;
        //DictTagAction *dictTagAction;
        TagAction *unknownTagHandler; // handler to help ignore all unknown tags




    }; // class XMLParser

} // namespace


// Local Variables:
// mode: C++
// End:

#endif