# The LearningOnline Network
# a pile of common routines
# 2/13 Guy Albertelli

# Makes a table out of the previous attempts
# Inputs result_from_symbread, user, domain, course_id

package Apache::loncommon;

use strict;
use POSIX qw(strftime);
use Apache::Constants qw(:common);
use Apache::lonmsg();

sub get_previous_attempt {
  my ($symb,$username,$domain,$course)=@_;
  my $prevattempts='';
  if ($symb) {
    my (%returnhash)=
      &Apache::lonnet::restore($symb,$course,$domain,$username);
    if ($returnhash{'version'}) {
      my %lasthash=();
      my $version;
      for ($version=1;$version<=$returnhash{'version'};$version++) {
        map {
	  $lasthash{$_}=$returnhash{$version.':'.$_};
        } sort(split(/\:/,$returnhash{$version.':keys'}));
      }
      $prevattempts='<table border=2></tr><th>History</th>';
      map {
        $prevattempts.='<th>'.$_.'</th>';
      } sort(keys %lasthash);
      for ($version=1;$version<=$returnhash{'version'};$version++) {
        $prevattempts.='</tr><tr><th>Attempt '.$version.'</th>';
        map {
	  my $value;
	  if ($_ =~ /timestamp/) {
	    $value=scalar(localtime($returnhash{$version.':'.$_}));
	  } else {
	    $value=$returnhash{$version.':'.$_};
	  }
	  $prevattempts.='<td>'.$value.'</td>';   
        } sort(keys %lasthash);
      }
      $prevattempts.='</tr><tr><th>Current</th>';
      map {
	my $value;
	if ($_ =~ /timestamp/) {
	  $value=scalar(localtime($lasthash{$_}));
	} else {
	  $value=$lasthash{$_};
	}
	$prevattempts.='<td>'.$value.'</td>';
      } sort(keys %lasthash);
      $prevattempts.='</tr></table>';
    } else {
      $prevattempts='Nothing submitted - no attempts.';
    }
  } else {
    $prevattempts='No data.';
  }
}

sub get_unprocessed_cgi {
  my ($query)= @_;
  map {
    my ($name, $value) = split(/=/,$_);
    $value =~ tr/+/ /;
    $value =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C",hex($1))/eg;
    if (!defined($ENV{'form.'.$name})) { $ENV{'form.'.$name}=$value; }
  } (split(/&/,$query));
}

sub cacheheader {
  my $date=strftime("%a, %d %b %Y %H:%M:%S GMT",gmtime);
  my $output .='<meta HTTP-EQUIV="Expires" CONTENT="'.$date.'" />
                <meta HTTP-EQUIV="Cache-control" CONTENT="no-cache" />
                <meta HTTP-EQUIV="Pragma" CONTENT="no-cache" />';
  return $output;
}

sub no_cache {
  my ($r) = @_;
  my $date=strftime("%a, %d %b %Y %H:%M:%S GMT",gmtime);
  $r->no_cache(1);
  $r->header_out("Pragma" => "no-cache");
  $r->header_out("Expires" => $date);
}
1;
__END__;