/* reader.c - a program for reading very large files

By Jeff Winston  http://www.kwcpa.com/tools
Rev. 1.2, 2/18/04 Copyright (C) 2002, 2003, 2004

type reader -h for more information

---------------------------------------------------------------------
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 2
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, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
USA.  or check out http://www.gnu.org/copyleft/gpl.html
---------------------------------------------------------------------

Rev 1.2 - added left border to display

To compile:  gcc reader.c -o reader

*/

#include  <string.h>        /* string library */        
#include  <stdio.h>         /* io library     */
#include  <math.h>          /* math library     */
#define MAXLINES 100000000    /* largest file that can be read */
#define MAXFAIL  5000       /* largest number of fail string pointers in linked list */

char tempstr[1023],     /* temporary string */
  failstring[1023],     /* definition of fail */
     infile[80],      /* input file name  */
     cur_line[1023],   /* current line of input file (for when file is read in) */
     instr[1023],      /* input command from the keyboard */
     cmd[10],         /* parsed command from input command */
     seastr[255],      /* parsed search string from the input command */
    tokens[32][32];

extern char * malloc();    /* declare MALLOC */

void type_range();
int find_string(char *field, char *source);
long get_tokens(char *str);


 
char *lineptr[MAXLINES];   /* pointer array */ 

char *p;                   /* pointer */

                 /* variables for reading the file in */
long limit,          /* max number of lines to read in */
    begin,          /* first line to read in */
    len,            /* length of input line */
    line,           /* total lines read in */
    crlf,           /* flag indicating a crlf needs to be added because line was shortened before storing */

                 /* variables for moving around the file */
    rtop,           /* top of current range */
    width,          /* length of current range (in lines) */

                 /* variables for special features */
    found,          /* flag used to indicate search success */
    mark,           /* marked line (for Mark function) */
    fail,           /* number of lines with fail string in them */
    failline[MAXFAIL], /* location of lines with Fail in them */
    curfail,        /* pointer into Failline */
    space_mode, /* extra space between long lines */
    gl,m,a,ntk,i,x,z;            /* temps */

FILE *infile_ptr, *outfile_ptr;    /* file pointers */

main(argc,argv)
int argc;                             /* Parse input and output file from command line */
char *argv[];
{

  printf("\nReader Rev 1.1 by J. Winston\n");
  ++argv;  
  if ((argc ==2) && (strcmp(*argv,"-h")==0))
    {

      printf("\nUse: reader <input file name>  [<arg1>] [<arg2>]\n");
      printf("Where arg1 and arg2 are not given, the entire file is read.\n");
      printf("If just arg1 is given, the first <arg1>*1000 lines of the file are read.\n");
      printf("If both arg1 and arg2 are given, the program reads <arg1>*1000 lines\n");
      printf("beginning at line <arg2>*1000.  \n\n");

      printf("The user then navigates the file within the program.\n\n");

      printf("One string can be coded into the program for special attention.\n");
      printf("The program creates a linked list of instances of this string\n");
      printf("which the user can quickly page through.  The default is \"fail\"\n");
      printf("(non-case sensitive). \n\n");

      printf("Type ?<CR> after loading a file for navigation commands\n\n");
      exit(0);
    }

    else if ((argc <2) || (argc>4)) 
    {
      printf("Error:  Incorrect number of parameters on command line\n");
      printf("Type reader -h for help\n");
      exit(0);
    }

    strcpy(infile,*argv);
    if ((infile_ptr=fopen(*argv, "r")) ==NULL)
    {
        printf("Error:  Error opening input file /%s/\n\n",infile);
        exit(1);
    }

    limit=MAXLINES; begin=0;                               /* initialize file read parameters, get args */
    if ((argc==3) || (argc==4))
    {
        ++argv;
        strcpy(tempstr,*argv);
        sscanf(tempstr,"%d",&z);
        if ((z*1000) < limit) limit=z*1000;
    }    
    if (argc==4)
    {
        ++argv;
        strcpy(tempstr,*argv);
        sscanf(tempstr,"%d",&begin);
        begin = begin*1000;
    }    
    m=0;gl=0;
    fail=0;                     /* initialize variables */
    curfail=0;
    failline[0]=0;
    space_mode=0;
    line=0; 
    rtop=0; 
    width=22;
    strcpy(seastr,"#*$#$");

    strcpy(failstring,"fail"); /* default fail string - case-sensitive*/

    printf("Reading input file...line 1");                /* read input file */
    fflush(stdout);
    if (begin >0)
    {
        z=begin;
	printf("...Advancing");
        while ((fgets(cur_line,1023,infile_ptr) != NULL) && (begin > 0)) 
     	{
     		begin--;
                if ( (begin/50000)*50000 == begin)
     		{
     		   printf("."); 
     		   fflush (stdout);
         	}
     	}
        printf("\n"); fflush(stdout);
        if (begin > 0) {printf("\nexiting at line #%d\n",z-begin);exit(0);}
    }
    x=0;
    while ((fgets(cur_line,511,infile_ptr) != NULL) && (line < limit)) 
    {
        len=strlen(cur_line);
        crlf=0;
        if (len > 1023)            /* trim strings to 1023 chars */
        {
            len=1023;
            crlf=1;
        }
        p=malloc(len+1+crlf);              /* <<<<<====== MALLOC */

        strncpy(p,cur_line,len+1+crlf);
        if (crlf ==1) strcat(p,"\n");  

        lineptr[line] = p;
        line++; 
     	if (fail < MAXFAIL)
        {
             if (find_string(cur_line,failstring)>0)         /* record FAILs in Fail array */
             {
                 failline[fail]=line;
                 fail++;
     		 if (fail == MAXFAIL) printf("\nLinked list of FAILs full (%d entries)\n",fail);
             }
        }
        if ( (line/50000)*50000 == line)          /* flag every 50K lines */
        {
                printf(", %dK",line/1000);
                fflush(stdout);
		x++;
        }        
        if ( x==10) 
	  {
	    printf("\n"); 
	    x=0;
	  }
    }

    if (fail > 0) 
      {
	/*	printf("\nDone! (%d lines, %d of which contain \\%s\\). Enter ?<CR> for help\n\n",line,fail,failstring);*/
	printf("\nDone! (%d lines). Enter ?<CR> for help\n\n",line);
      }
    else if (line >= limit) 
      {
	printf("\nDone.  Max size exceeded (%d lines). Enter ?<CR> for help\n\n",line);     
      }
    else printf("\nDone! (%d lines). Enter ?<CR> for help\n\n",line);     
                   
    mark = 1;
    while (fgets(instr,255,stdin)  != NULL)                  /* let user view file however he wants */
    {
        len = strlen(instr); 
	
        if (len <2) type_range();
        else 
        {
	    x = len - 1;
	    if (instr[x] == '\n') instr[x] = '\0';

            sscanf(instr,"%s",cmd); 
            if (strcmp(cmd,"?")==0)
     	    {
	     printf("<CR>      Repeat last command\n");
	     printf("r         Refresh screen\n");
             printf("t/b       Goto Top/Bottom of document\n");
             printf("a/p       Move ahead/back one window\n");
             printf("h/H       Move ahead/back 1/2 window\n");
             printf("n/l       Move ahead/back one line\n");
             printf("w <#>     Adjust window size (# of lines displayed) to <#>\n");
             printf("m/M       Mark top line / goto mark \n");
             printf("W <f>     Write file <f> with lines from file, starting at\n");
             printf("             marked line and ending at current bottom line\n");
             printf("g <#>     Goto line <#>\n");
	     printf("gf/gb <#> Go forward/back <#> lines\n");
             printf("f/F <s>   Find string <s> searching forward/backward.  If <s>\n");
             printf("             is omitted, searches for next instance of last <s>\n");
	     /*             printf("ff/FF     Goto next/last line with string \\%s\\ in linked list\n",failstring); */
             printf("other:    x/q =  Quit  s = toggle space_mode\n");
     	    }
        
            else if (strcmp(cmd,"x")==0) exit(0);          /* quit */
            else if (strcmp(cmd,"q")==0) exit(0);
            else if (strcmp(cmd,"r")==0) type_range();
            else if (strcmp(cmd,"m")==0)                       /* mark location */
            {
                mark=rtop;
                printf("Marked line %d. ",rtop);
                type_range();
            }    

            else if (strcmp(cmd,"M")==0)                       /* mark location */
            {
	        rtop = mark;
                type_range();
            }    

            else if (strcmp(cmd,"t")==0)                         /* Top of Document */
            {
                rtop=0;
                curfail=0;
                type_range();
            }

            else if (strcmp(cmd,"b")==0)                         /* Bottom of Document */
            {
                curfail=fail;
                rtop=(line)-width;
                type_range();
            }
            else if (strcmp(cmd,"a")==0)                          /* Advance Range */
            {
                rtop=rtop+width-1;  
                if (rtop > (line)-width) rtop = (line)-width;
                type_range();
            }
            else if (strcmp(cmd,"n")==0)                          /* next line */
            {
                rtop++;  
                if (rtop > (line)-width) rtop = (line)-width;
                type_range();
            }
            else if (strcmp(cmd,"p")==0)                          /* Prior range*/
            {
                rtop=rtop-width+1;  
                if (rtop <0) rtop =0;
                type_range();
            }
            else if (strcmp(cmd,"h")==0)                          /* next 1/2 range */
            {
                rtop=rtop+width/2-1;
                if (rtop > (line)-width) rtop = (line)-width;
                type_range();
            }
            else if (strcmp(cmd,"H")==0)                          /* Prior 1/2 range*/
            {
                rtop=rtop-width/2+1;  
                if (rtop <0) rtop =0;
                type_range();
            }
            else if (strcmp(cmd,"s")==0)                          /* space mode */
            {
	      if (space_mode == 0) space_mode=1;
	      else space_mode = 0;
                type_range();
            }
            else if (strcmp(cmd,"W")==0)                          /* write section to file */
            {
                sscanf(instr,"%s %s",cmd,tempstr);
                
                if ((outfile_ptr=fopen(tempstr, "w")) ==NULL)
                {
                    printf("Error:  Error opening %s as output\n",tempstr);
                }
                else
                {
                  for (i=mark; i < rtop+width; i++)
                    fprintf(outfile_ptr,"%s",lineptr[i]);
		  fclose(outfile_ptr);
		  printf("Lines %d to %d Written to %s\n",mark,rtop+width,tempstr);
		  type_range();
                }    
            }
            else if (strcmp(cmd,"l")==0)                         /* Last Line */
            {
                rtop--;  
                if (rtop <0) rtop =0;
                type_range();
            }
            else if (strcmp(cmd,"w")==0)                        /* Width */
            {
                sscanf(instr,"%s %d",cmd,&width);
		if (width < 1) width = 20;
		if (width > line) width = line;
                type_range();
            }                                                    /* select line */
            else if (strcmp(cmd,"g")==0)   
            {
                sscanf(instr,"%s %d",cmd,&rtop);
		if (rtop < (width/2)) rtop = 0;
		else if (rtop > line-width) rtop = line-width;
		else rtop = rtop - (width/2);
		gl=1;
                type_range();
		gl=0;
            }
            else if (strcmp(cmd,"gf")==0)   
            {
                sscanf(instr,"%s %d",cmd,&x);
		if (x < 0) x = 0;
		rtop = rtop + x;
		if (rtop > (line-width)) rtop = line-width;
                type_range();
            }
            else if (strcmp(cmd,"gb")==0)   
            {
                sscanf(instr,"%s %d",cmd,&x);
		if (x < 0) x = 0;
		rtop= rtop - x;
		if (rtop <0) rtop = 0;
                type_range();
            }
            else if (strcmp(cmd,"ff")==0)                    /* find fail forward */
            {
              if (fail > 0)
              {
                rtop = failline[curfail] - width/2;
                if (curfail < fail) curfail++;
                type_range();
              }
     	      else
     	      {
     		 printf("No Failures.\n ");
     	      }
            }
            else if (strcmp(cmd,"FF")==0)                    /* find fail backward */
            {
              if (fail > 0)
              {
                if (curfail >0)  curfail--;
                rtop = failline[curfail] - width/2;
                type_range();
              }                     
     	      else
     	      {
     		 printf("No Failures.\n ");
     	      }
            }                                               /* find string forward */
            else if (strcmp(cmd,"f")==0)   
            {
                if (strlen(instr) !=1)  ntk = get_tokens(instr);
                i=rtop+width/2; z=i;found=0;
                printf("Finding /%s/...",seastr);
                fflush(stdout);
                while ((i<line) && (found==0))
	        {
		  m=1;
		     found=1;
	             for (a=1;a<ntk;a++)
		     	if (find_string(lineptr[i],tokens[a])==0) {found=0;a=ntk;}
                     if ((found==0) && (i == z+50000))
                     {
                         z=i;
                         printf("."); 
                         fflush(stdout);
                     }
                     i++;
                }             
                if (found ==0) printf(" -not found- ");
                else
                {
                    if (i > (line-width)) rtop=line-width; 
                    else rtop=i-width/2;
                }
		printf("\n"); 
                type_range();
            }
            else if (strcmp(cmd,"F")==0)                    /* find string backward */
            {
                if (strlen(instr) !=1)  ntk = get_tokens(instr);
                i=rtop+width/2; found=0; z=i;
                printf("Finding \\%s\\...",seastr);
                fflush(stdout);
		while ((i>0) && (found==0))
	        {
		     found=1;
	             for (a=1;a<ntk;a++)
		     	if (find_string(lineptr[i],tokens[a])==0) {found=0;a=ntk;}
                     if ((found==0) && (i == z-10000))
                     {
                         z=i;
                         printf("."); 
                         fflush(stdout);
                     }
                     i--;
		}
                if (found ==0) printf(" -not found- ");
                else
                {
		  m=1;i=i+2;
                    if (i==1) rtop=i;
                    else rtop=i-width/2;
		    if (rtop <0) rtop = 0;
                }
                type_range();
		if (rtop>0) rtop=rtop-2;
            }

            else printf("Unrecognized command %s (enter ? for help)\n",cmd);
       }   
   }
}
void type_range()                                         /* type current range to screen */
{
  int q;
    printf("[%d/%d]:\n",rtop,rtop+width-1);
    for (i=rtop; i<(rtop+width); i++)
    {
      if (((m==1) && (found==1)) && ((i-rtop) == (width/2-1))) printf(">>");
      else if ((gl==1) && ((i-rtop) == (width/2))) printf(">>");
      else 
	{
	  q = i-((i/10) * 10);
	  if ((i != rtop) && (space_mode == 1)) printf("\n");
	  printf("%1d|",q);
	}
        printf("%s",lineptr[i]);
        /* if (strlen(lineptr[i]) > 80)
                  printf("    %s",&lineptr[i][79]);*/                 
    }
    m=0;
}
int find_string(char *field, char *source)         /* returns LOC of substring in string  */
{
    int flen;
    int slen; 
    char    *sPtr;
    int loc;

    flen = strlen(field);
    slen = strlen(source);
    if (slen > flen) return (0);     /* error */
    else
    {
        for (loc=0, sPtr = field; loc <= flen-slen; loc++, sPtr++)
        {
            if (strncmp(source,sPtr, slen) ==0) return(loc+1);
        }
    }
    return (0);
}
long get_tokens(char *str)           /* get tokens on line. Put in global tokens[32][32], return  count */
{
   long len, loc, cnt, sp, start,x;

   len = strlen(str);  sp=1; cnt=0;
   for (loc=0; loc <= len; loc++)
   {
       if ( (loc < len) && (str[loc] != ' ') && (str[loc] !=','))
       {
           if (sp==1)
           {
               cnt++;
               sp=0;
               start=loc;
           }
       }
       else
       {
           if (sp==0)
           {
               sp=1;
               strncpy(tokens[cnt-1],&str[start],loc-start);
               strncpy(&tokens[cnt-1][loc-start],"\0",1);

           }
       }
   }
   strncpy(seastr,&instr[2],strlen(instr)-2);
   strncpy(&seastr[strlen(instr)-2],"\0",1);
   return(cnt);
}