#include <algorithm>

#include "src/storage/expressions/BinaryNumericalFunctionExpression.h"
#include "src/exceptions/ExceptionMacros.h"
#include "src/exceptions/InvalidTypeException.h"

namespace storm {
    namespace expressions {
        BinaryNumericalFunctionExpression::BinaryNumericalFunctionExpression(ExpressionReturnType returnType, std::shared_ptr<BaseExpression const> const& firstOperand, std::shared_ptr<BaseExpression const> const& secondOperand, OperatorType operatorType) : BinaryExpression(returnType, firstOperand, secondOperand), operatorType(operatorType) {
            // Intentionally left empty.
        }
        
        BinaryNumericalFunctionExpression::OperatorType BinaryNumericalFunctionExpression::getOperatorType() const {
            return this->operatorType;
        }
        
        storm::expressions::OperatorType BinaryNumericalFunctionExpression::getOperator() const {
            switch (this->getOperatorType()) {
                case OperatorType::Plus: return storm::expressions::OperatorType::Plus; break;
                case OperatorType::Minus: return storm::expressions::OperatorType::Minus; break;
                case OperatorType::Times: return storm::expressions::OperatorType::Times; break;
                case OperatorType::Divide: return storm::expressions::OperatorType::Divide; break;
                case OperatorType::Min: return storm::expressions::OperatorType::Min; break;
                case OperatorType::Max: return storm::expressions::OperatorType::Max; break;
            }
        }
        
        int_fast64_t BinaryNumericalFunctionExpression::evaluateAsInt(Valuation const* valuation) const {
            LOG_THROW(this->hasIntegralReturnType(), storm::exceptions::InvalidTypeException, "Unable to evaluate expression as integer.");
            
            int_fast64_t firstOperandEvaluation = this->getFirstOperand()->evaluateAsInt(valuation);
            int_fast64_t secondOperandEvaluation = this->getSecondOperand()->evaluateAsInt(valuation);
            switch (this->getOperatorType()) {
                case OperatorType::Plus: return firstOperandEvaluation + secondOperandEvaluation; break;
                case OperatorType::Minus: return firstOperandEvaluation - secondOperandEvaluation; break;
                case OperatorType::Times: return firstOperandEvaluation * secondOperandEvaluation; break;
                case OperatorType::Divide: return firstOperandEvaluation / secondOperandEvaluation; break;
                case OperatorType::Min: return std::min(firstOperandEvaluation, secondOperandEvaluation); break;
                case OperatorType::Max: return std::max(firstOperandEvaluation, secondOperandEvaluation); break;
            }
        }
        
        double BinaryNumericalFunctionExpression::evaluateAsDouble(Valuation const* valuation) const {
            LOG_THROW(this->hasNumericalReturnType(), storm::exceptions::InvalidTypeException, "Unable to evaluate expression as double.");
            
            double firstOperandEvaluation = this->getFirstOperand()->evaluateAsDouble(valuation);
            double secondOperandEvaluation = this->getSecondOperand()->evaluateAsDouble(valuation);
            switch (this->getOperatorType()) {
                case OperatorType::Plus: return static_cast<double>(firstOperandEvaluation + secondOperandEvaluation); break;
                case OperatorType::Minus: return static_cast<double>(firstOperandEvaluation - secondOperandEvaluation); break;
                case OperatorType::Times: return static_cast<double>(firstOperandEvaluation * secondOperandEvaluation); break;
                case OperatorType::Divide: return static_cast<double>(firstOperandEvaluation / secondOperandEvaluation); break;
                case OperatorType::Min: return static_cast<double>(std::min(firstOperandEvaluation, secondOperandEvaluation)); break;
                case OperatorType::Max: return static_cast<double>(std::max(firstOperandEvaluation, secondOperandEvaluation)); break;
            }
        }
        
        std::shared_ptr<BaseExpression const> BinaryNumericalFunctionExpression::simplify() const {
            std::shared_ptr<BaseExpression const> firstOperandSimplified = this->getFirstOperand()->simplify();
            std::shared_ptr<BaseExpression const> secondOperandSimplified = this->getSecondOperand()->simplify();
            
            if (firstOperandSimplified.get() == this->getFirstOperand().get() && secondOperandSimplified.get() == this->getSecondOperand().get()) {
                return this->shared_from_this();
            } else {
                return std::shared_ptr<BaseExpression>(new BinaryNumericalFunctionExpression(this->getReturnType(), firstOperandSimplified, secondOperandSimplified, this->getOperatorType()));
            }
        }
        
        void BinaryNumericalFunctionExpression::accept(ExpressionVisitor* visitor) const {
            visitor->visit(this);
        }
        
        void BinaryNumericalFunctionExpression::printToStream(std::ostream& stream) const {
            stream << "(";
            switch (this->getOperatorType()) {
                case OperatorType::Plus: stream << *this->getFirstOperand() << " + " << *this->getSecondOperand(); break;
                case OperatorType::Minus: stream << *this->getFirstOperand() << " - " << *this->getSecondOperand(); break;
                case OperatorType::Times: stream << *this->getFirstOperand() << " * " << *this->getSecondOperand(); break;
                case OperatorType::Divide: stream << *this->getFirstOperand() << " / " << *this->getSecondOperand(); break;
                case OperatorType::Min: stream << "min(" << *this->getFirstOperand() << ", " << *this->getSecondOperand() << ")"; break;
                case OperatorType::Max: stream << "max(" << *this->getFirstOperand() << ", " << *this->getSecondOperand() << ")"; break;
            }
            stream << ")";
        }
    }
}