/home/renji/Data/projects/zenlang/sources/zbl/Scanner.hpp

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#pragma once
#include "Token.hpp"

namespace zbl {
    class Scanner {
    private:
        inline int read() {
            //assert(_stream.pos() == _npos); // pos() is a *very* expensive operation in Qt (at least 100x).
            if(_stream.end()) {
                //assert(_ch > 0);
                _ch = 0;
            } else {
                _ch = _stream.getChar();
                if( _ch == '\n') {
                    ++_line;
                    _col = 0;
                }
                ++_col;
            }
            return _ch;
        }

        inline int get(const int& pos) {
            assert(pos == _npos);
            return _ch;
        }

        inline bool next() {
            if(_ch == 0) {
                _ch = 1;
                return false;
            }
            if(_ch == 1) {
                return false;
            }
            _string += _ch;
            ++_npos;
            read();
            return true;
        }

    public:
        inline Scanner(z::stream& stream)
        : _stream(stream), _ch(0), _tokenPos(0), _npos(0), _line(1), _col(0), _ccol(1), _tcol(1), start(*this), marker(*this), end(*this) {
            read();
        }
    public:
        class cursor {
        public:
            inline cursor(Scanner& scanner) : _scanner(scanner), _pos(0) {}

        public:
            inline int operator*() {
                return _scanner.get(_pos);
            }

            inline cursor& operator++() {
                if(_scanner.next())
                    ++_pos;
                return ref(this);
            }

            inline cursor& operator=(const cursor& src) {
                _pos = src._pos;
                return ref(this);
            }

        private:
            Scanner& _scanner;

            int _pos;
        };
    private:
        inline z::string resetToken() {
            _ccol = _tcol;
            z::string s = _string;
            _string = z::string("");
            _tokenPos = _npos;
            _tcol = _col;
            return s;
        }
    public:
        inline const z::string& getString() const {return _string;}

        inline const int& getLine() const {return _line;}

        inline const int& getCol() const {return _col;}

    public:
        inline z::string getToken() {
            return resetToken();
        }

    public:
        inline Token createToken(const int& id, const z::string& s, const bool& hidden) {
            return Token(id, s, hidden, _line, _ccol);
        }

        inline Token createToken(const int& id, const bool& hidden) {
            z::string s = resetToken();
            return Token(id, s, hidden, _line, _ccol);
        }

        inline Token createQuotedToken(const int& id, const bool& hidden) {
            z::string s = resetToken();
            assert(s.length() >= 2);
            s = s.mid(1, s.length() - 2);
            return Token(id, s, hidden, _line, _ccol);
        }

        inline Token createTrimmedToken(const int& id, const bool& hidden) {
            z::string s = resetToken();
            assert(s.length() >= 1);
            s = s.mid(1);
            return Token(id, s, hidden, _line, _ccol);
        }

    private:
        z::stream& _stream;

        z::queue<int> _queue;

        z::string _string;

        int _ch;

        int _tokenPos;

        int _npos;

    private:
        int _line;

        int _col;

        int _ccol;

        int _tcol;

    public:
        cursor start;

        cursor marker;

        cursor end;
    };
};