o3de/Gems/ExpressionEvaluation/Code/Source/ExpressionEngine/MathOperators/MathExpressionOperators.h

/*
 * Copyright (c) Contributors to the Open 3D Engine Project.
 * For complete copyright and license terms please see the LICENSE at the root of this distribution.
 *
 * SPDX-License-Identifier: Apache-2.0 OR MIT
 *
 */
#pragma once

#include <AzCore/Memory/SystemAllocator.h>

#include <ExpressionEngine/ExpressionElementParser.h>

namespace ExpressionEvaluation
{
    class MathExpressionOperators
        : public ExpressionElementParser
    {
    public:
        AZ_CLASS_ALLOCATOR(MathExpressionOperators, AZ::SystemAllocator);

        enum MathExpressionOperatorPriority
        {
            Unknown = -1,
            AddSubtract = 0,
            MultiplyDivideModulo = 1,
            Power = 2,
            Function = 3
        };

        enum MathOperatorId
        {
            Add = 0,
            Subtract,
            Multiply,
            Divide,
            Modulo
        };

        static ElementInformation AddOperator();
        static ElementInformation SubtractOperator();
        static ElementInformation MultiplyOperator();
        static ElementInformation DivideOperator();
        static ElementInformation ModuloOperator();

        MathExpressionOperators() = default;
        ~MathExpressionOperators() override = default;

        ExpressionParserId GetParserId() const override;

        ParseResult ParseElement(const AZStd::string& inputText, size_t offset) const override;
        void EvaluateToken(const ElementInformation& elementInformation, ExpressionResultStack& evaluationStack) const override;

    private:

        ExpressionResult OnAddOperator(const AZStd::any& leftValue, const AZStd::any& rightValue) const;
        ExpressionResult OnSubtractOperator(const AZStd::any& leftValue, const AZStd::any& rightValue) const;
        ExpressionResult OnMultiplyOperator(const AZStd::any& leftValue, const AZStd::any& rightValue) const;
        ExpressionResult OnDivideOperator(const AZStd::any& leftValue, const AZStd::any& rightValue) const;
        ExpressionResult OnModuloOperator(const AZStd::any& leftValue, const AZStd::any& rightValue) const;
    };
}