//      /bin/system/_grep.c
//      from the Dead Souls Mudlib
//      searches for an expression in files
//      created by Descartes of Borg 930822
//        numbered results added by Nimrod@The Tower 060805

#include <lib.h>

#define GREP_NUMBERED_LINES            (1<<0)
#define GREP_RECURSE_DIRECTORIES    (1<<1)

inherit LIB_DAEMON;

int cmd(string str) {
    mapping borg;
    string *lines, *files, *r_files;
    string output, exp, file, tmp, txt;

    int i, i_lines, max, max_lines, flags;

    notify_fail("Correct syntax: <grep [-nr] '[pattern]' [file] (> [output])>\n");
    if(!str) return 0;
    //CHECK FOR FLAGS
    if(str[0] == '-'){
	if(sscanf(str, "-%s %s", tmp, txt) == 2){
	    for(i = 0, max = sizeof(tmp); i<max; i++){
		switch(tmp[i]){
		case 'n' : flags = flags|GREP_NUMBERED_LINES ;break;
		case 'r' : flags = flags|GREP_RECURSE_DIRECTORIES ;break;
		}
	    }
	}
	str = txt;
    }
    if(sscanf(str, "%s > %s", tmp, output) == 2) {
	if(output[0] != '/') output = (string)previous_object()->get_path()+"/"+output;
	str = tmp;
    }
    else output = 0;
    if(sscanf(str, "'%s' %s", exp, file) != 2 &&
      sscanf(str, "%s %s", exp, file) != 2) return 0;
    if(!(max = sizeof(files = (string *)previous_object()->wild_card(file)))) {         message("system", "File not found.", this_player());
	return 1;
    }

    if(flags&GREP_NUMBERED_LINES){
	for(i=0, borg = ([]); i<max; i++) {
	    if((file_size(files[i]) == -2)&&(flags&GREP_RECURSE_DIRECTORIES)){
		r_files = (string *)previous_object()->wild_card(files[i]+"/"+file);
		files += r_files;
		max += sizeof(r_files);
		continue;
	    }
	    if(!(txt = read_file(files[i]))) continue;
	    lines = explode(txt, "\n");
	    borg[files[i]] = ({});
	    for(i_lines = 0, max_lines = sizeof(lines); i_lines<max_lines; i_lines++){
		if(regexp(lines[i_lines], exp)){
		    borg[files[i]] += ({sprintf("%d: %s", i_lines, lines[i_lines]) });
		}
	    }
	    if(!sizeof(borg[files[i]])) map_delete(borg, files[i]);
	}
    }
    else {
	for(i=0, borg = ([]); i<max; i++) {

	    if((file_size(files[i]) == -2)&&(flags&GREP_RECURSE_DIRECTORIES)){
		r_files = (string *)previous_object()->wild_card(files[i]+"/"+file);
		files += r_files;
		max += sizeof(r_files);
		continue;
	    }
	    if(!(txt = read_file(files[i]))) continue;
	    borg[files[i]] = regexp(explode(txt, "\n"), exp);
	    if(!sizeof(borg[files[i]])) map_delete(borg, files[i]);
	}
    }
    if(!(max = sizeof(files = keys(borg)))) str = "No matches found.\n";
    else {
	for(i=0, str = ""; i<max; i++)           str += sprintf("%s:\n%s\n\n", files[i], implode(borg[files[i]],"\n"));
    }
    if(output) {
	if(!write_file(output, str)) message("system", "Failed to write to: "+output, this_player());
	else message("system", "Grep sent to: "+output, this_player());
    }
    else message("Nsystem", str, this_player());
    return 1;
}

void help() {
    message("help",
      "Syntax: <grep [-nr] '[pattern]' [file] (> [redirect])>\n\n"
      "Searches a file or group of files for a specific pattern.  "
      "If the pattern is a single word, then no '' is needed.  Patterns "
      "of more than one word or beginning with a '-' however, need to be enclosed in ''.  "
      "You may redirect the output of the grep to to a file using the >."
      "\n  Options:\n"
      "    -r  recursive search, search extends to child directories.\n"
      "    -n  numbered lines, includes line numbers of successful hits."
      "\n\nSee also: cd, ls, mv, pwd, rm", this_player()
    );
}