#!/usr/bin/perl
#
# This perl CGI script enables document distribution using SwiftView(R)
# SwiftView, Inc.
#
# flush stdout buffer
$| = 1;
#
# MIME type = any type defined for SwiftView(R) Plug-in so that
# browsers starts it.  SwiftView looks in the file itself so
# this can be one MIME type for all returned files.
# Don't send type until we know if we need to send status - we must
# send status, else SwiftView will count http://foo.001 files forever.
#
# Debugging:
$Debug = 1;
if ($Debug) {
   open(perllog, ">>/tmp/perllog");
   while (($Key,$Value) = each %ENV) {
       print perllog "\t$Key=$Value\n";
   }
}
if ($ENV{'HTTP_USER_AGENT'} eq 'contype')
{
    # IE POST workaround: IE sends three requests, 1/2 need only return
    # mime, second needs only content type, sends content type = "contype",
    # and has a 10 second timeout.
    # IE5.5, 4.6.00: POST now is sometimes followed by two GETS, the first one
    # is "contype".
    print "Content-type: application/vnd.SwiftView-ICS\n\n";
    if ($Debug) {
       print perllog "got contype, return just Content-type\n";
   }
    exit 0;
}
# check for the POST method - used for forms
if ($ENV{'REQUEST_METHOD'} eq 'POST')
{
    # How many bytes are we supposed to receive?
    read(STDIN, $Buffer, $ENV{'CONTENT_LENGTH'});
    # make a list of keyword/value pairs
    @pairs = split(/&/, $Buffer);
    # cycle through each pair and decipher the values
    foreach $Pair (@pairs)
    {
        # get the name/value pair strings
        ($Name, $Value) = split(/=/, $Pair);
        # translate "+" to a space
        $Value =~ tr/+/ /;
        # decipher ASCII hexidecimal escaped characters, if any
        $Value =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C", hex($1))/eg;
        # add the pair to a list keyed on the name of the variable
        $Contents{$Name} = $Value;
        if ($Debug) {
           print perllog "$Name=$Value "; 
        }
    }
}
# check for the GET method - used for links
if ($ENV{REQUEST_METHOD} eq 'GET' && 
    $ENV{QUERY_STRING} ne '') {
    # split the query string into an array of keywords
    foreach $Widget (split("&", $ENV{QUERY_STRING})) {
      # get the keyword and value pair from the widget string
      if ($Widget =~ /(.*)=(.*)/)  {
         ($Key, $Value) = ($1, $2); 
          $Value =~ s/\+/ /g ; # replace "+" with " "
          # unescape ASCII hexadecimal characters
          $Value =~ s/%(..)/pack('c',hex($1))/eg;
          $Contents{$Key} = $Value; # add keyword/value pair to a list
      }
    }
}
if ($Debug) {
   print perllog "\n"; 
}

# The server-side filename is now in the name variable
# Require all paths be relative to DOCUMENT_ROOT
$DOCUMENT_ROOT = $ENV{'DOCUMENT_ROOT'};
if ($DOCUMENT_ROOT eq '') {
   # fallback for most servers, many do not have DOCUEMENT_ROOT.
   $DOCUMENT_ROOT = $ENV{'PATH_TRANSLATED'};
}

if (!open(datafile, "$DOCUMENT_ROOT/$Contents{'name'}")) {
    # print "HTTP/1.0 404 Not Found\n";
    print "Content-type: application/vnd.SwiftView-ICS\n\n";
    print "Could not open file \"", $Contents{'name'}, "\"\n";
    print "QUERY_STRING = \"", $ENV{'QUERY_STRING'}, "\"\n";
    print "CONTENT_LENGTH = \"", $ENV{'CONTENT_LENGTH'}, "\"\n";
    print "content = \"", $Buffer, "\"\n";
    exit 1;
}
print "Content-type: application/vnd.SwiftView-ICS\n\n";
while(<datafile>) {
    print;
}