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 *   Copyright (c) 2005-2026 by                                             *
 *       - Pierre-Henri WUILLEMIN(_at_LIP6)                                 *
 *       - Christophe GONZALES(_at_AMU)                                     *
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 *   SPDX-FileCopyrightText: Copyright 2005-2026                            *
 *       - Pierre-Henri WUILLEMIN(_at_LIP6)                                 *
 *       - Christophe GONZALES(_at_AMU)                                     *
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/**
 * @file
 * @brief Headers of the MDDOperatorStrategy planer class.
 *
 * @author Pierre-Henri WUILLEMIN(_at_LIP6) and Jean-Christophe MAGNAN and Christophe
 * GONZALES(_at_AMU)
 */

// =========================================================================
#ifndef GUM_MDD_OPERATOR_STRATEGY_H
#define GUM_MDD_OPERATOR_STRATEGY_H
// =========================================================================
#include <agrum/FMDP/planning/IOperatorStrategy.h>

// =========================================================================

namespace gum {

  /**
   * @class MDDOperatorStrategy mddOperatorStrategy.h
   * <agrum/FMDP/planning/mddOperatorStrategy.h>
   * @brief A class to find optimal policy for a given FMDP.
   * @ingroup fmdp_group
   *
   * Perform a SPUDD planning on given in parameter factored markov decision
   * process
   *
   */
  template < typename GUM_ELEMENT >
  class MDDOperatorStrategy: public IOperatorStrategy< GUM_ELEMENT > {
    public:
    // ###################################################################
    /// @name Constructor & destructor.
    // ###################################################################
    /// @{

    /**
     * Default constructor
     */
    MDDOperatorStrategy();

    /**
     * Default destructor
     */
    ~MDDOperatorStrategy() override;

    /// @}


    // ###################################################################
    /// @name
    // ###################################################################
    /// @{

    MultiDimFunctionGraph< GUM_ELEMENT, ExactTerminalNodePolicy >* getFunctionInstance() override;

    MultiDimFunctionGraph< ArgMaxSet< GUM_ELEMENT, Idx >, SetTerminalNodePolicy >*
        getArgMaxFunctionInstance() override;

    MultiDimFunctionGraph< ActionSet, SetTerminalNodePolicy >* getAggregatorInstance() override;

    /// @}

    // ###################################################################
    /// @name Graph Function Operations Methods
    // ###################################################################
    /// @{

    protected:
    // ==========================================================================
    /**
     *  Computes Qaction for given actionid
     */
    // ==========================================================================
    MultiDimFunctionGraph< GUM_ELEMENT >* regress(const MultiDimFunctionGraph< GUM_ELEMENT >* Vold,
                                                  Idx                        actionId,
                                                  const FMDP< GUM_ELEMENT >* fmdp,
                                                  const gum::VariableSet&    elVarSeq) override;

    // ==========================================================================
    /// @warning given vFunction and qAction are deleted, returns the new one
    // ==========================================================================
    MultiDimFunctionGraph< GUM_ELEMENT >* maximize(const MultiDimFunctionGraph< GUM_ELEMENT >* f1,
                                                   const MultiDimFunctionGraph< GUM_ELEMENT >* f2,
                                                   Idx del = 3) override;

    // ==========================================================================
    /// @warning Minimze the two given functions
    // ==========================================================================
    MultiDimFunctionGraph< GUM_ELEMENT >* minimize(const MultiDimFunctionGraph< GUM_ELEMENT >* f1,
                                                   const MultiDimFunctionGraph< GUM_ELEMENT >* f2,
                                                   Idx del = 3) override;

    // ==========================================================================
    /// @warning given f1 and f2 are deleted, returns the new one
    // ==========================================================================
    MultiDimFunctionGraph< GUM_ELEMENT >* multiply(const MultiDimFunctionGraph< GUM_ELEMENT >* f1,
                                                   const MultiDimFunctionGraph< GUM_ELEMENT >* f2,
                                                   Idx del = 3) override;

    // ==========================================================================
    /// @warning given vFunction and qAction are deleted, returns the new one
    // ==========================================================================
    MultiDimFunctionGraph< ArgMaxSet< GUM_ELEMENT, Idx >, SetTerminalNodePolicy >* argmaximize(
        const MultiDimFunctionGraph< ArgMaxSet< GUM_ELEMENT, Idx >, SetTerminalNodePolicy >* f1,
        const MultiDimFunctionGraph< ArgMaxSet< GUM_ELEMENT, Idx >, SetTerminalNodePolicy >* f2,
        Idx del = 3) override;

    // ==========================================================================
    /// @warning given function is deleted, returns the new one
    // ==========================================================================
    MultiDimFunctionGraph< GUM_ELEMENT >* add(const MultiDimFunctionGraph< GUM_ELEMENT >* f1,
                                              const MultiDimFunctionGraph< GUM_ELEMENT >* f2,
                                              Idx del = 1) override;

    // ==========================================================================
    /// @warning this time, nothing is deleted
    // ==========================================================================
    MultiDimFunctionGraph< GUM_ELEMENT >* subtract(const MultiDimFunctionGraph< GUM_ELEMENT >* f1,
                                                   const MultiDimFunctionGraph< GUM_ELEMENT >* f2,
                                                   Idx del = 0) override;


    /// @}

    protected:
    // ==========================================================================
    /// Indicates if whether or not given var is to be eliminated.
    /// Called by the evalQaction.
    // ==========================================================================
    bool shouldEleminateVar_(const DiscreteVariable* v, const FMDP< GUM_ELEMENT >* fmdp);

    // ==========================================================================
    /// Returns the last var in the var order for given graph function
    /// Called by the evalQaction.
    // ==========================================================================
    const DiscreteVariable* lastVar_(const MultiDimFunctionGraph< GUM_ELEMENT >* function);
  };
} /* namespace gum */

#include <agrum/FMDP/planning/mddOperatorStrategy_tpl.h>

#endif   // GUM_MDD_OPERATOR_STRATEGY_H
