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** Copyright (c) 2008 Nokia Corporation and/or its subsidiary(-ies).
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** alternatively, in accordance with the terms contained in a written
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** GNU General Public License Usage
**
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** Public License versions 2.0 or 3.0 as published by the Free Software
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/*
  Copyright 2005 Roberto Raggi <roberto@kdevelop.org>

  Permission to use, copy, modify, distribute, and sell this software and its
  documentation for any purpose is hereby granted without fee, provided that
  the above copyright notice appear in all copies and that both that
  copyright notice and this permission notice appear in supporting
  documentation.

  The above copyright notice and this permission notice shall be included in
  all copies or substantial portions of the Software.

  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
  KDEVELOP TEAM BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/

#ifndef PP_ENGINE_H
#define PP_ENGINE_H

#include "pp-client.h"

#include <Token.h>
#include <QVector>

namespace CPlusPlus {
    class Token;
}

namespace CPlusPlus {

    struct Value
    {
        enum Kind {
            Kind_Long,
            Kind_ULong,
        };

        Kind kind;

        union {
            long l;
            unsigned long ul;
        };


        Value()
            : kind(Kind_Long), l(0)
        { }

        inline bool is_ulong () const
        { return kind == Kind_ULong; }

        inline void set_ulong (unsigned long v)
        {
            ul = v;
            kind = Kind_ULong;
        }

        inline void set_long (long v)
        {
            l = v;
            kind = Kind_Long;
        }

        inline bool is_zero () const
        { return l == 0; }

#define PP_DEFINE_BIN_OP(name, op) \
        inline Value operator op(const Value &other) const \
        { \
            Value v = *this; \
            if (v.is_ulong () || other.is_ulong ()) \
                v.set_ulong (v.ul op other.ul); \
            else \
                v.set_long (v.l op other.l); \
            return v; \
        }

        PP_DEFINE_BIN_OP(op_add, +)
        PP_DEFINE_BIN_OP(op_sub, -)
        PP_DEFINE_BIN_OP(op_mult, *)
        PP_DEFINE_BIN_OP(op_div, /)
        PP_DEFINE_BIN_OP(op_mod, %)
        PP_DEFINE_BIN_OP(op_lhs, <<)
        PP_DEFINE_BIN_OP(op_rhs, >>)
        PP_DEFINE_BIN_OP(op_lt, <)
        PP_DEFINE_BIN_OP(op_gt, >)
        PP_DEFINE_BIN_OP(op_le, <=)
        PP_DEFINE_BIN_OP(op_ge, >=)
        PP_DEFINE_BIN_OP(op_eq, ==)
        PP_DEFINE_BIN_OP(op_ne, !=)
        PP_DEFINE_BIN_OP(op_bit_and, &)
        PP_DEFINE_BIN_OP(op_bit_or, |)
        PP_DEFINE_BIN_OP(op_bit_xor, ^)
        PP_DEFINE_BIN_OP(op_and, &&)
        PP_DEFINE_BIN_OP(op_or, ||)

#undef PP_DEFINE_BIN_OP
    };

    class CPLUSPLUS_EXPORT pp
    {
        Client *client;
        Environment &env;
        MacroExpander expand;

        enum { MAX_LEVEL = 512 };

        bool _skipping[MAX_LEVEL]; // ### move in state
        bool _true_test[MAX_LEVEL]; // ### move in state
        int iflevel; // ### move in state

        enum PP_DIRECTIVE_TYPE
        {
            PP_UNKNOWN_DIRECTIVE,
            PP_DEFINE,
            PP_INCLUDE,
            PP_INCLUDE_NEXT,
            PP_ELIF,
            PP_ELSE,
            PP_ENDIF,
            PP_IF,
            PP_IFDEF,
            PP_IFNDEF,
            PP_UNDEF
        };

        typedef const CPlusPlus::Token *TokenIterator;

        struct State {
            QByteArray source;
            QVector<CPlusPlus::Token> tokens;
            TokenIterator dot;
        };

        QList<State> _savedStates;

        State state() const;
        void pushState(const State &state);
        void popState();

        QByteArray _source;
        QVector<CPlusPlus::Token> _tokens;
        TokenIterator _dot;

        State createStateFromSource(const QByteArray &source) const;

    public:
        pp(Client *client, Environment &env);

        void operator()(const QByteArray &filename,
                        const QByteArray &source,
                        QByteArray *result);

        void operator()(const QByteArray &source,
                        QByteArray *result);

    private:
        void resetIfLevel();
        bool testIfLevel();
        int skipping() const;

        PP_DIRECTIVE_TYPE classifyDirective(const QByteArray &directive) const;

        Value evalExpression(TokenIterator firstToken,
                             TokenIterator lastToken,
                             const QByteArray &source) const;

        QVector<CPlusPlus::Token> tokenize(const QByteArray &text) const;

        const char *startOfToken(const CPlusPlus::Token &token) const;
        const char *endOfToken(const CPlusPlus::Token &token) const;

        QByteArray tokenSpell(const CPlusPlus::Token &token) const;
        QByteArray tokenText(const CPlusPlus::Token &token) const; // does a deep copy

        void processDirective(TokenIterator dot, TokenIterator lastToken);
        void processInclude(bool skipCurrentPath,
                            TokenIterator dot, TokenIterator lastToken,
                            bool acceptMacros = true);
        void processDefine(TokenIterator dot, TokenIterator lastToken);
        void processIf(TokenIterator dot, TokenIterator lastToken);
        void processElse(TokenIterator dot, TokenIterator lastToken);
        void processElif(TokenIterator dot, TokenIterator lastToken);
        void processEndif(TokenIterator dot, TokenIterator lastToken);
        void processIfdef(bool checkUndefined,
                          TokenIterator dot, TokenIterator lastToken);
        void processUndef(TokenIterator dot, TokenIterator lastToken);

        bool isQtReservedWord(const QByteArray &name) const;
    };

} // namespace CPlusPlus

#endif // PP_ENGINE_H