/* 
**  (C) 2008 by Remo Dentato (rdentato@users.sourceforge.net)
**
** Permission to use, copy, modify and distribute this code and
** its documentation for any purpose is hereby granted without
** fee, provided that the above copyright notice, or equivalent
** attribution acknowledgement, appears in all copies and
** supporting documentation.
** 
** Copyright holder makes no representations about the suitability
** of this software for any purpose. It is provided "as is" without
** express or implied warranty.
**
*/

#include <stdio.h>
#include <stdlib.h>
#include <strings.h>
#include <ctype.h>

#define RX_MAXNFA 4096
#include "rx.h"

unsigned char nfa[RX_MAXNFA];

#define ln_len 2048
char ln[ln_len];

FILE *tmpf;
FILE *inf;
FILE *outf;

char resvar[128];
char strvar[128];

int swnum = 0;
int rxnum = 0;
int lnnum = 0;

int error(char *errmsg)
{
  fprintf(stderr,errmsg);  
  exit(1);
}

void outrx(int sym)
{
  if (*nfa) {
    fprintf(outf,"static unsigned char RX_%d[]= { /* %d */\n",swnum,strlen(nfa)+1);
    rx_dump_num(outf,nfa);
    fprintf(outf,"\n};\n");
    if (sym) {
      fprintf(outf,"\n/*\n");
      rx_dump_asm(outf,nfa);
      fprintf(outf,"\n*/\n");
    }
  }
}

#define IN_CODE    1
#define IN_COMMENT 2

int main(int argc, char *argv[])
{
  char *s,*t;
  char *err;
  int c;
  int state = IN_CODE;
  int argn = 1;  
  int sym = 0;
  rx_result r;
  
  char *fname = "(stdin)";
    
  *nfa = '\0';
  inf  = stdin;
  outf = stdout;
  
  tmpf = tmpfile();
  if (tmpf == NULL) error("ERR202: Unable to open temp file");
  
  while ((argn < argc) && (argv[argn][0] == '-')) {
    if (argv[argn][1] == 's') sym = 1;
    argn++;
  }
    
  if (argn < argc) {
    fname = argv[argn];
    inf = fopen(fname,"r");
    if (inf == NULL) error("ERR203: Unable to open input file");
  }
  
  while ((s = fgets(ln,ln_len,inf))) {
    ++lnnum;
    while (*s) {
      switch(state) {
      
        case IN_CODE :
          RX_SWITCH(r,s) { 
            case "^\/\*"     : state = IN_COMMENT;
            case "^\s+"      : 
            case "^\Q"       : 
            case "^//.*"     : 
            case "^[^R/c\"]+": rx_write(r,0,tmpf);
                               break;
               
            case "^case *{\Q} *:" : 
                              fprintf(tmpf,"case %d :",++rxnum);
                              rx_end(r,1)[-1] = '\0';
                              err = rx_compile_add(rx_start(r,1)+1,nfa);
                              if (err) {
                                fprintf(stderr,"%d:ERR205: %s\n",lnnum,err);
                                exit(1);
                              }
                              break;

            case "^RX_SWITCH *\( *{\I} *, *{\I} *\)" :
                              outrx(sym);
                              rx_cpy(r,1,resvar);
                              rx_cpy(r,2,strvar);
                              fprintf(tmpf,"RX_SWITCH(%s,%s,%d)",resvar,strvar,++swnum);
                              rxnum = 0;
                              *nfa = '\0';
                              break;      

            case "^RX_{\u+} *\(" :
                              fputs("rx_",tmpf);
                              t = rx_start(r,1);
                              while (t < rx_end(r,1))
                                fputc(tolower(*t++),tmpf);
                              fprintf(tmpf,"(%s,",resvar);
                              break;      
                                   
            default :         if (*s) fputc(*s++,tmpf);
                              break;                        
          }      
          break;
          
        case IN_COMMENT :
        
          RX_SWITCH(r,s) {
            case "^\*\/"   : state = IN_CODE;
            case "^[^\*]+" : rx_write(r,0,tmpf);
                             break;
               
            default :        if (*s) fputc(*s++,tmpf);
                             break;         
          }      
          break;
            
        default :  error("Unexpected state!");
                   break;                        
      }
    }
  }
  
  outrx(sym);
  fprintf(outf,"#define RX_SWITCH(r,s,n) switch ((r = rx_exec(RX_##n,s))? (s=rx_end(r,0),rx_matched(r)) : 0)\n");
  fprintf(outf,"#line 1 \"%s\"\n",fname);
  
  fseek(tmpf,SEEK_SET,0);
  
  while ((c = fgetc(tmpf)) != EOF) 
    fputc(c,outf);
  
  if (outf != stdout) fclose(outf);
  if (inf  != stdin)  fclose(inf);
  fclose(tmpf);
  exit(0);
}