/*

Copyright (c) 2007 Carl Byington - 510 Software Group, released under
the GPL version 3 or any later version at your choice available at
http://www.gnu.org/licenses/gpl-3.0.txt

*/

using namespace std;

struct ltstr {
    bool operator()(const char* s1, const char* s2) const {
        return strcmp(s1, s2) < 0;
    }
};

typedef list<ifstream *>            stream_list;
typedef list<const char *>          string_list;
typedef set<const char *, ltstr>    string_set;
typedef list<int>                   line_list;

class TOKEN {
    stream_list streams;
    string_list filenames;
    string_set  filenamess;
    line_list   linenumbers;
    string_list pending_tokens;
    string_set  *include_files;
    bool        pushed;
    u_char      pushed_char;

    void pop();
    bool next_char(u_char &c);
    void push_char(u_char c);

public:
    TOKEN(const char *fn, string_set *includes);
    ~TOKEN();
    bool        include(const char *fn);
    const char  *next();            // return next token
    int         nextint();
    void        skipeol();          // skip to eol
    void        push(const char *token) {pending_tokens.push_front(token);};
    const char  *cur_fn()               {return filenames.empty()   ? "" : filenames.front();};
    int         cur_line()              {return linenumbers.empty() ? 0  : linenumbers.front();};
    void        token_error(const char *err);
    void        token_error(const char *fmt, int d, const char *s);
    void        token_error(const char *fmt, const char *t, const char *h);
    void        token_error(const char *want, const char *have);
    void        token_error();
};