/*

 * Cppcheck - A tool for static C/C++ code analysis

 * Copyright (C) 2007-2017 Cppcheck team.

 *

 * This program is free software: you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation, either version 3 of the License, or

 * (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program.  If not, see <http://www.gnu.org/licenses/>.

 */

//---------------------------------------------------------------------------

#ifndef valueflowH

#define valueflowH

//---------------------------------------------------------------------------

#include "config.h"

#include <list>

#include <string>

#include <utility>

class ErrorLogger;

class Settings;

class SymbolDatabase;

class Token;

class TokenList;

namespace ValueFlow {

    class CPPCHECKLIB Value {

    public:

        typedef std::pair<const Token *, std::string> ErrorPathItem;

        typedef std::list<ErrorPathItem> ErrorPath;

        explicit Value(long long val = 0) : valueType(INT), intvalue(val), tokvalue(nullptr), floatValue(0.0), moveKind(NonMovedVariable), varvalue(val), condition(nullptr), varId(0U), conditional(false), defaultArg(false), valueKind(ValueKind::Possible) {}

        Value(const Token *c, long long val);

        bool operator==(const Value &rhs) const {

            if (valueType != rhs.valueType)

                return false;

            switch (valueType) {

            case INT:

                if (intvalue != rhs.intvalue)

                    return false;

                break;

            case TOK:

                if (tokvalue != rhs.tokvalue)

                    return false;

                break;

            case FLOAT:

                // TODO: Write some better comparison

                if (floatValue > rhs.floatValue || floatValue < rhs.floatValue)

                    return false;

                break;

            case MOVED:

                if (moveKind != rhs.moveKind)

                    return false;

                break;

            case UNINIT:

                break;

            };

            return varvalue == rhs.varvalue &&

                   condition == rhs.condition &&

                   varId == rhs.varId &&

                   conditional == rhs.conditional &&

                   defaultArg == rhs.defaultArg &&

                   valueKind == rhs.valueKind;

        }

        std::string infoString() const;

        enum ValueType { INT, TOK, FLOAT, MOVED, UNINIT } valueType;

        bool isIntValue() const {

            return valueType == INT;

        }

        bool isTokValue() const {

            return valueType == TOK;

        }

        bool isFloatValue() const {

            return valueType == FLOAT;

        }

        bool isMovedValue() const {

            return valueType == MOVED;

        }

        bool isUninitValue() const {

            return valueType == UNINIT;

        }

        /** int value */

        long long intvalue;

        /** token value - the token that has the value. this is used for pointer aliases, strings, etc. */

        const Token *tokvalue;

        /** float value */

        double floatValue;

        /** kind of moved  */

        enum MoveKind {NonMovedVariable, MovedVariable, ForwardedVariable} moveKind;

        /** For calculated values - variable value that calculated value depends on */

        long long varvalue;

        /** Condition that this value depends on */

        const Token *condition;

        ErrorPath errorPath;

        /** For calculated values - varId that calculated value depends on */

        unsigned int varId;

        /** Conditional value */

        bool conditional;

        /** Is this value passed as default parameter to the function? */

        bool defaultArg;

        static const char * toString(MoveKind moveKind) {

            switch (moveKind) {

            case NonMovedVariable:

                return "NonMovedVariable";

            case MovedVariable:

                return "MovedVariable";

            case ForwardedVariable:

                return "ForwardedVariable";

            }

            return "";

        }

        /** How known is this value */

        enum ValueKind {

            /** This value is possible, other unlisted values may also be possible */

            Possible,

            /** Only listed values are possible */

            Known,

            /** Inconclusive */

            Inconclusive

        } valueKind;

        void setKnown() {

            valueKind = ValueKind::Known;

        }

        bool isKnown() const {

            return valueKind == ValueKind::Known;

        }

        void setPossible() {

            valueKind = ValueKind::Possible;

        }

        bool isPossible() const {

            return valueKind == ValueKind::Possible;

        }

        void setInconclusive(bool inconclusive = true) {

            if (inconclusive)

                valueKind = ValueKind::Inconclusive;

        }

        bool isInconclusive() const {

            return valueKind == ValueKind::Inconclusive;

        }

        void changeKnownToPossible() {

            if (isKnown())

                valueKind = ValueKind::Possible;

        }

        bool errorSeverity() const {

            return !condition && !defaultArg;

        }

    };

    /// Constant folding of expression. This can be used before the full ValueFlow has been executed (ValueFlow::setValues).

    const ValueFlow::Value * valueFlowConstantFoldAST(const Token *expr, const Settings *settings);

    /// Perform valueflow analysis.

    void setValues(TokenList *tokenlist, SymbolDatabase* symboldatabase, ErrorLogger *errorLogger, const Settings *settings);

    std::string eitherTheConditionIsRedundant(const Token *condition);

}

#endif // valueflowH