// cd34, v0.1, 2002-02-05
// http://daviesinc.com/modules/
//
int thread_safe=1;
#include <module.h>

inherit "module";
inherit "caudiumlib";

constant module_type = MODULE_FIRST;
constant module_name = "Skimmer Module";
constant module_doc  = "";
constant module_unique = 1;

object incl=0,excl=0;
int redirected=0,passed=0;

void create() {
  defvar("skim", 5, "Skim %", TYPE_INT,
         "This will take x% of the incoming requests for an .html doc and redirect them to a different URL");
  defvar("topdir", 0, "Skim Top Directory?", TYPE_FLAG,
         "Do you want to skim traffic from the top directory?");
  defvar("redirecturl", "NONE/", "Where are we sending the traffic?", TYPE_STRING,
         "");
  defvar("regexpinclude", "\.(htm|html|shtml|rxml)$|/$",
         "Regexp Include Specification", TYPE_STRING,
         "An expression here will include processing for anything that matches this Pike Syntax Regexp<br>"
         "For Example:<br>.*<br>will include processing for all files.  id->not_query is automatically "
         "lowercased."
         "<br>"
         "\\.(htm|html|shtml|rxml)$|/$");
  defvar("regexpexclude", "\.(jpg|jpeg|gif|png)$|^/_internal",
         "Regexp Exclude Specification", TYPE_STRING,
         "An expression here will exclude processing for anything that matches this Pike Syntax Regexp<br>"
         "For Example:<br>\\.(jpg|jpeg|gif|png)$|^/_internal <br>will exclude processing for jpg, gif and png files "
         "id->not_query is automatically lowercased");
}

void start(int num, object conf) {
  catch {
    if (strlen(query("regexpinclude")))
      incl = Regexp(query("regexpinclude"));
    if (strlen(query("regexpexclude")))
      excl = Regexp(query("regexpexclude"));
  };
}


string status() {
  return (sprintf("%d redirected, %d passed. %3.2f%% of the traffic is being redirected",
                  redirected,passed,(passed>0)?(float)redirected/((float)passed+(float)redirected)*100.0:0.0));
}

mapping first_try(object id) {

  if (QUERY(topdir)==0 && String.count(id->not_query,"/")<2)
    return 0;

//perror("match: "+id->not_query+" "+incl->match(lower_case(id->not_query))+"\n");
//perror("exclude: "+excl->match(lower_case(id->not_query))+"\n");
  if (id->not_query && (incl && !incl->match(lower_case(id->not_query))) ||
      (excl &&  excl->match(lower_case(id->not_query))))
    return(0);

  if (random(100) < QUERY(skim)) {
    redirected++;
    return http_redirect(QUERY(redirecturl));
  }

  passed++;
  return 0;
}