#pragma once

#include <string>

#include <boost/optional.hpp>

#include "storm/storage/expressions/Variable.h"
#include "storm/storage/expressions/Expression.h"

namespace storm {
    namespace jani {
        
        class Constant {
        public:
            /*!
             * Creates a constant.
             */
            Constant(std::string const& name, storm::expressions::Variable const& variable, storm::expressions::Expression const& definingExpression = storm::expressions::Expression(), storm::expressions::Expression const& constraintExpression = storm::expressions::Expression());
            
            /*!
             * Retrieves the name of the constant.
             */
            std::string const& getName() const;
            
            /*!
             * Retrieves whether the constant is defined in the sense that it has a defining expression.
             */
            bool isDefined() const;
            
            /*!
             * Defines the constant with the given expression.
             * If a constraintExpression is set, it is checked whether the constant definition satisfies the given constraint.
             */
            void define(storm::expressions::Expression const& expression);
            
            /*!
             * Retrieves the type of the constant.
             */
            storm::expressions::Type const& getType() const;
            
            /*!
             * Retrieves whether the constant is a boolean constant.
             */
            bool isBooleanConstant() const;
            
            /*!
             * Retrieves whether the constant is an integer constant.
             */
            bool isIntegerConstant() const;
            
            /*!
             * Retrieves whether the constant is a real constant.
             */
            bool isRealConstant() const;
            
            /*!
             * Retrieves the expression variable associated with this constant.
             */
            storm::expressions::Variable const& getExpressionVariable() const;
            
            /*!
             * Retrieves the expression that defines this constant (if any).
             */
            storm::expressions::Expression const& getExpression() const;
            
            /*!
             * Retrieves whether there is a constraint for the possible values of this constant
             */
             bool hasConstraint() const;
             
             /*!
              * Retrieves the expression that constraints the possible values of this constant (if any).
              */
            storm::expressions::Expression const& getConstraintExpression() const;
             
             /*!
              * Sets a constraint expression. An exception is thrown if this constant is defined and the definition violates the given constraint.
              */
             void setConstraintExpression(storm::expressions::Expression const& expression);
            
        private:
            // The name of the constant.
            std::string name;
            
            // The expression variable associated with the constant.
            storm::expressions::Variable variable;

            // The expression defining the constant (if any).
            storm::expressions::Expression definingExpression;

            // The expression constraining possible values of the constant (if any).
            storm::expressions::Expression constraintExpression;
        };
        
    }
}