--- loncom/interface/loncommon.pm	2001/12/11 19:37:12	1.14
+++ loncom/interface/loncommon.pm	2002/07/01 15:24:44	1.42
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # a pile of common routines
 #
-# $Id: loncommon.pm,v 1.14 2001/12/11 19:37:12 harris41 Exp $
+# $Id: loncommon.pm,v 1.42 2002/07/01 15:24:44 matthew Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -27,103 +27,849 @@
 #
 # YEAR=2001
 # 2/13-12/7 Guy Albertelli
-# 12/11 Scott Harrison
+# 12/11,12/12,12/17 Scott Harrison
+# 12/21 Gerd Kortemeyer
+# 12/21 Scott Harrison
+# 12/25,12/28 Gerd Kortemeyer
+# YEAR=2002
+# 1/4 Gerd Kortemeyer
 
 # Makes a table out of the previous attempts
 # Inputs result_from_symbread, user, domain, course_id
+# Reads in non-network-related .tab files
 
+# POD header:
+
+=head1 NAME
+
+Apache::loncommon - pile of common routines
+
+=head1 SYNOPSIS
+
+Referenced by other mod_perl Apache modules.
+
+Invocation:
+ &Apache::loncommon::SUBROUTINENAME(ARGUMENTS);
+
+=head1 INTRODUCTION
+
+Common collection of used subroutines.  This collection helps remove
+redundancy from other modules and increase efficiency of memory usage.
+
+Current things done:
+
+ Makes a table out of the previous homework attempts
+ Inputs result_from_symbread, user, domain, course_id
+ Reads in non-network-related .tab files
+
+This is part of the LearningOnline Network with CAPA project
+described at http://www.lon-capa.org.
+
+=head2 General Subroutines
+
+=over 4
+
+=cut 
+
+# End of POD header
 package Apache::loncommon;
 
 use strict;
+use Apache::lonnet();
 use POSIX qw(strftime);
 use Apache::Constants qw(:common);
 use Apache::lonmsg();
+my $readit;
 
+# ----------------------------------------------- Filetypes/Languages/Copyright
 my %language;
 my %cprtag;
 my %fe; my %fd;
+my %category_extensions;
+
+# -------------------------------------------------------------- Thesaurus data
+my @therelated;
+my @theword;
+my @thecount;
+my %theindex;
+my $thetotalcount;
+my $thefuzzy=2;
+my $thethreshold=0.1/$thefuzzy;
+my $theavecount;
 
 # ----------------------------------------------------------------------- BEGIN
-sub BEGIN {
+
+=pod
+
+=item BEGIN() 
+
+Initialize values from language.tab, copyright.tab, filetypes.tab,
+and filecategories.tab.
+
+=cut
+# ----------------------------------------------------------------------- BEGIN
+
+BEGIN {
+
+    unless ($readit) {
 # ------------------------------------------------------------------- languages
     {
 	my $fh=Apache::File->new($Apache::lonnet::perlvar{'lonTabDir'}.
 				 '/language.tab');
-	while (<$fh>) {
-	    next if /^\#/;
-	    chomp;
-	    my ($key,$val)=(split(/\s+/,$_,2));
-	    $language{$key}=$val;
+	if ($fh) {
+	    while (<$fh>) {
+		next if /^\#/;
+		chomp;
+		my ($key,$val)=(split(/\s+/,$_,2));
+		$language{$key}=$val;
+	    }
 	}
     }
 # ------------------------------------------------------------------ copyrights
     {
+	my $fh=Apache::File->new($Apache::lonnet::perlvar{'lonIncludes'}.
+				  '/copyright.tab');
+	if ($fh) {
+	    while (<$fh>) {
+		next if /^\#/;
+		chomp;
+		my ($key,$val)=(split(/\s+/,$_,2));
+		$cprtag{$key}=$val;
+	    }
+	}
+    }
+# ------------------------------------------------------------- file categories
+    {
 	my $fh=Apache::File->new($Apache::lonnet::perlvar{'lonTabDir'}.
-				 '/copyright.tab');
-	while (<$fh>) {
-	    next if /^\#/;
-	    chomp;
-	    my ($key,$val)=(split(/\s+/,$_,2));
-	    $cprtag{$key}=$val;
+				  '/filecategories.tab');
+	if ($fh) {
+	    while (<$fh>) {
+		next if /^\#/;
+		chomp;
+		my ($extension,$category)=(split(/\s+/,$_,2));
+		push @{$category_extensions{lc($category)}},$extension;
+	    }
 	}
     }
 # ------------------------------------------------------------------ file types
     {
-	my $fh=Apache::File->new("$perlvar{'lonTabDir'}/filetypes.tab");
-	while (<$fh>) {
-	    next if (/^\#/);
-	    chomp;
-	    my ($ending,$emb,$descr)=split(/\s+/,$_,3);
-	    if ($descr ne '') { 
-		$fe{$ending}=lc($emb);
-		$fd{$ending}=join(' ',@descr);
+	my $fh=Apache::File->new($Apache::lonnet::perlvar{'lonTabDir'}.
+	       '/filetypes.tab');
+	if ($fh) {
+            while (<$fh>) {
+		next if (/^\#/);
+		chomp;
+		my ($ending,$emb,$descr)=split(/\s+/,$_,3);
+		if ($descr ne '') { 
+		    $fe{$ending}=lc($emb);
+		    $fd{$ending}=$descr;
+		}
 	    }
 	}
     }
+# -------------------------------------------------------------- Thesaurus data
+    {
+	my $fh=Apache::File->new($Apache::lonnet::perlvar{'lonTabDir'}.
+	       '/thesaurus.dat');
+	if ($fh) {
+            while (<$fh>) {
+               my ($tword,$tindex,$tcount,$trelated)=split(/\@/,$_);
+               $theindex{$tword}=$tindex;
+               $theword[$tindex]=$tword;
+               $thecount[$tindex]=$tcount;
+               $thetotalcount+=$tcount;
+               $therelated[$tindex]=$trelated;
+	   }
+        }
+        $theavecount=$thetotalcount/$#thecount;
+    }
+    &Apache::lonnet::logthis(
+              "<font color=yellow>INFO: Read file types and thesaurus</font>");
+    $readit=1;
+}
+    
+}
+# ============================================================= END BEGIN BLOCK
+###############################################################
+##           HTML and Javascript Helper Functions            ##
+###############################################################
+
+=pod 
+
+=item browser_and_searcher_javascript 
+
+Returns scalar containing javascript to open a browser window
+or a searcher window.  Also creates 
+
+=over 4
+
+=item openbrowser(formname,elementname,only,omit) [javascript]
+
+inputs: formname, elementname, only, omit
+
+formname and elementname indicate the name of the html form and name of
+the element that the results of the browsing selection are to be placed in. 
+
+Specifying 'only' will restrict the browser to displaying only files
+with the given extension.  Can be a comma seperated list.
+
+Specifying 'omit' will restrict the browser to NOT displaying files
+with the given extension.  Can be a comma seperated list.
+
+=item opensearcher(formname, elementname) [javascript]
+
+Inputs: formname, elementname
+
+formname and elementname specify the name of the html form and the name
+of the element the selection from the search results will be placed in.
+
+=back
+
+=cut
+
+###############################################################
+sub browser_and_searcher_javascript {
+    return <<END;
+    var editbrowser;
+    function openbrowser(formname,elementname,only,omit) {
+        var url = '/res/?';
+        if (editbrowser == null) {
+            url += 'launch=1&';
+        }
+        url += 'catalogmode=interactive&';
+        url += 'mode=edit&';
+        url += 'form=' + formname + '&';
+        if (only != null) {
+            url += 'only=' + only + '&';
+        } 
+        if (omit != null) {
+            url += 'omit=' + omit + '&';
+        }
+        url += 'element=' + elementname + '';
+        var title = 'Browser';
+        var options = 'scrollbars=1,resizable=1,menubar=0';
+        options += ',width=700,height=600';
+        editbrowser = open(url,title,options,'1');
+        editbrowser.focus();
+    }
+    var editsearcher;
+    function opensearcher(formname,elementname) {
+        var url = '/adm/searchcat?';
+        if (editsearcher == null) {
+            url += 'launch=1&';
+        }
+        url += 'catalogmode=interactive&';
+        url += 'mode=edit&';
+        url += 'form=' + formname + '&';
+        url += 'element=' + elementname + '';
+        var title = 'Search';
+        var options = 'scrollbars=1,resizable=1,menubar=0';
+        options += ',width=700,height=600';
+        editsearcher = open(url,title,options,'1');
+        editsearcher.focus();
+    }
+END
+}
+
+
+
+###############################################################
+
+=pod
+
+=item linked_select_forms(...)
+
+linked_select_forms returns a string containing a <script></script> block
+and html for two <select> menus.  The select menus will be linked in that
+changing the value of the first menu will result in new values being placed
+in the second menu.  The values in the select menu will appear in alphabetical
+order.
+
+linked_select_forms takes the following ordered inputs:
+
+=over 4
+
+=item $formname, the name of the <form> tag
+
+=item $middletext, the text which appears between the <select> tags
+
+=item $firstdefault, the default value for the first menu
+
+=item $firstselectname, the name of the first <select> tag
+
+=item $secondselectname, the name of the second <select> tag
+
+=item $hashref, a reference to a hash containing the data for the menus.
+
+=back 
+
+Below is an example of such a hash.  Only the 'text', 'default', and 
+'select2' keys must appear as stated.  keys(%menu) are the possible 
+values for the first select menu.  The text that coincides with the 
+first menu value is given in $menu{$choice1}->{'text'}.  The values 
+and text for the second menu are given in the hash pointed to by 
+$menu{$choice1}->{'select2'}.  
+
+my %menu = ( A1 => { text =>"Choice A1" ,
+                      default => "B3",
+                      select2 => { 
+                          B1 => "Choice B1",
+                          B2 => "Choice B2",
+                          B3 => "Choice B3",
+                          B4 => "Choice B4"
+                          }
+                  },
+              A2 => { text =>"Choice A2" ,
+                      default => "C2",
+                      select2 => { 
+                          C1 => "Choice C1",
+                          C2 => "Choice C2",
+                          C3 => "Choice C3"
+                          }
+                  },
+              A3 => { text =>"Choice A3" ,
+                      default => "D6",
+                      select2 => { 
+                          D1 => "Choice D1",
+                          D2 => "Choice D2",
+                          D3 => "Choice D3",
+                          D4 => "Choice D4",
+                          D5 => "Choice D5",
+                          D6 => "Choice D6",
+                          D7 => "Choice D7"
+                          }
+                  }
+              );
+
+=back
+
+=cut
+
+# ------------------------------------------------
+
+sub linked_select_forms {
+    my ($formname,
+        $middletext,
+        $firstdefault,
+        $firstselectname,
+        $secondselectname, 
+        $hashref
+        ) = @_;
+    my $second = "document.$formname.$secondselectname";
+    my $first = "document.$formname.$firstselectname";
+    # output the javascript to do the changing
+    my $result = '';
+    $result.="<script>\n";
+    $result.="var select2data = new Object();\n";
+    $" = '","';
+    my $debug = '';
+    foreach my $s1 (sort(keys(%$hashref))) {
+        $result.="select2data.d_$s1 = new Object();\n";        
+        $result.="select2data.d_$s1.def = new String('".
+            $hashref->{$s1}->{'default'}."');\n";
+        $result.="select2data.d_$s1.values = new Array(";        
+        my @s2values = sort(keys( %{ $hashref->{$s1}->{'select2'} } ));
+        $result.="\"@s2values\");\n";
+        $result.="select2data.d_$s1.texts = new Array(";        
+        my @s2texts;
+        foreach my $value (@s2values) {
+            push @s2texts, $hashref->{$s1}->{'select2'}->{$value};
+        }
+        $result.="\"@s2texts\");\n";
+    }
+    $"=' ';
+    $result.= <<"END";
+
+function select1_changed() {
+    // Determine new choice
+    var newvalue = "d_" + $first.value;
+    // update select2
+    var values     = select2data[newvalue].values;
+    var texts      = select2data[newvalue].texts;
+    var select2def = select2data[newvalue].def;
+    var i;
+    // out with the old
+    for (i = 0; i < $second.options.length; i++) {
+        $second.options[i] = null;
+    }
+    // in with the nuclear
+    for (i=0;i<values.length; i++) {
+        $second.options[i] = new Option(values[i]);
+        $second.options[i].text = texts[i];
+        if (values[i] == select2def) {
+            $second.options[i].selected = true;
+        }
+    }
+}
+</script>
+END
+    # output the initial values for the selection lists
+    $result .= "<select size=\"1\" name=\"$firstselectname\" onchange=\"select1_changed()\">\n";
+    foreach my $value (sort(keys(%$hashref))) {
+        $result.="    <option value=\"$value\" ";
+        $result.=" selected=\"true\" " if ($value eq $firstdefault);
+        $result.=">$hashref->{$value}->{'text'}</option>\n";
+    }
+    $result .= "</select>\n";
+    my %select2 = %{$hashref->{$firstdefault}->{'select2'}};
+    $result .= $middletext;
+    $result .= "<select size=\"1\" name=\"$secondselectname\">\n";
+    my $seconddefault = $hashref->{$firstdefault}->{'default'};
+    foreach my $value (sort(keys(%select2))) {
+        $result.="    <option value=\"$value\" ";        
+        $result.=" selected=\"true\" " if ($value eq $seconddefault);
+        $result.=">$select2{$value}</option>\n";
+    }
+    $result .= "</select>\n";
+    #    return $debug;
+    return $result;
+}   #  end of sub linked_select_forms {
+
+###############################################################
+
+=item csv_translate($text) 
+
+Translate $text to allow it to be output as a 'comma seperated values' 
+format.
+
+=cut
+
+sub csv_translate {
+    my $text = shift;
+    $text =~ s/\"/\"\"/g;
+    $text =~ s/\n//g;
+    return $text;
+}
+
+###############################################################
+
+###############################################################
+##        Home server <option> list generating code          ##
+###############################################################
+#-------------------------------------------
+
+=item get_domains()
+
+Returns an array containing each of the domains listed in the hosts.tab
+file.
+
+=cut
+
+#-------------------------------------------
+sub get_domains {
+    # The code below was stolen from "The Perl Cookbook", p 102, 1st ed.
+    my @domains;
+    my %seen;
+    foreach (sort values(%Apache::lonnet::hostdom)) {
+        push (@domains,$_) unless $seen{$_}++;
+    }
+    return @domains;
+}
+
+#-------------------------------------------
+
+=item select_dom_form($defdom,$name)
+
+Returns a string containing a <select name='$name' size='1'> form to 
+allow a user to select the domain to preform an operation in.  
+See loncreateuser.pm for an example invocation and use.
+
+=cut
+
+#-------------------------------------------
+sub select_dom_form {
+    my ($defdom,$name) = @_;
+    my @domains = get_domains();
+    my $selectdomain = "<select name=\"$name\" size=\"1\">\n";
+    foreach (@domains) {
+        $selectdomain.="<option value=\"$_\" ".
+            ($_ eq $defdom ? 'selected' : '').
+                ">$_</option>\n";
+    }
+    $selectdomain.="</select>";
+    return $selectdomain;
+}
+
+#-------------------------------------------
+
+=item get_home_servers($domain)
+
+Returns a hash which contains keys like '103l3' and values like 
+'kirk.lite.msu.edu'.  All of the keys will be for machines in the
+given $domain.
+
+=cut
+
+#-------------------------------------------
+sub get_home_servers {
+    my $domain = shift;
+    my %home_servers;
+    foreach (keys(%Apache::lonnet::libserv)) {
+        if ($Apache::lonnet::hostdom{$_} eq $domain) {
+            $home_servers{$_} = $Apache::lonnet::hostname{$_};
+        }
+    }
+    return %home_servers;
+}
+
+#-------------------------------------------
+
+=item home_server_option_list($domain)
+
+returns a string which contains an <option> list to be used in a 
+<select> form input.  See loncreateuser.pm for an example.
+
+=cut
+
+#-------------------------------------------
+sub home_server_option_list {
+    my $domain = shift;
+    my %servers = &get_home_servers($domain);
+    my $result = '';
+    foreach (sort keys(%servers)) {
+        $result.=
+            '<option value="'.$_.'">'.$_.' '.$servers{$_}."</option>\n";
+    }
+    return $result;
+}
+###############################################################
+##    End of home server <option> list generating code       ##
+###############################################################
+
+###############################################################
+##    Authentication changing form generation subroutines    ##
+###############################################################
+##
+## All of the authform_xxxxxxx subroutines take their inputs in a
+## hash, and have reasonable default values.
+##
+##    formname = the name given in the <form> tag.
+#-------------------------------------------
+
+=item authform_xxxxxx
+
+The authform_xxxxxx subroutines provide javascript and html forms which 
+handle some of the conveniences required for authentication forms.  
+This is not an optimal method, but it works.  
+
+See loncreateuser.pm for invocation and use examples.
+
+=over 4
+
+=item authform_header
+
+=item authform_authorwarning
+
+=item authform_nochange
+
+=item authform_kerberos
+
+=item authform_internal
+
+=item authform_filesystem
+
+=back
+
+=cut
+
+#-------------------------------------------
+sub authform_header{  
+    my %in = (
+        formname => 'cu',
+        kerb_def_dom => 'MSU.EDU',
+        @_,
+    );
+    $in{'formname'} = 'document.' . $in{'formname'};
+    my $result='';
+    $result.=<<"END";
+var current = new Object();
+current.radiovalue = 'nochange';
+current.argfield = null;
+
+function changed_radio(choice,currentform) {
+    var choicearg = choice + 'arg';
+    // If a radio button in changed, we need to change the argfield
+    if (current.radiovalue != choice) {
+        current.radiovalue = choice;
+        if (current.argfield != null) {
+            currentform.elements[current.argfield].value = '';
+        }
+        if (choice == 'nochange') {
+            current.argfield = null;
+        } else {
+            current.argfield = choicearg;
+            switch(choice) {
+                case 'krb': 
+                    currentform.elements[current.argfield].value = 
+                        "$in{'kerb_def_dom'}";
+                break;
+              default:
+                break;
+            }
+        }
+    }
+    return;
+}
+
+function changed_text(choice,currentform) {
+    var choicearg = choice + 'arg';
+    if (currentform.elements[choicearg].value !='') {
+        switch (choice) {
+            case 'krb': currentform.elements[choicearg].value =
+                currentform.elements[choicearg].value.toUpperCase();
+                break;
+            default:
+        }
+        // clear old field
+        if ((current.argfield != choicearg) && (current.argfield != null)) {
+            currentform.elements[current.argfield].value = '';
+        }
+        current.argfield = choicearg;
+    }
+    set_auth_radio_buttons(choice,currentform);
+    return;
+}
+
+function set_auth_radio_buttons(newvalue,currentform) {
+    var i=0;
+    while (i < currentform.login.length) {
+        if (currentform.login[i].value == newvalue) { break; }
+        i++;
+    }
+    if (i == currentform.login.length) {
+        return;
+    }
+    current.radiovalue = newvalue;
+    currentform.login[i].checked = true;
+    return;
+}
+END
+    return $result;
+}
+
+sub authform_authorwarning{
+    my $result='';
+    $result=<<"END";
+<i>As a general rule, only authors or co-authors should be filesystem
+authenticated (which allows access to the server filesystem).</i>
+END
+    return $result;
+}
+
+sub authform_nochange{  
+    my %in = (
+              formname => 'document.cu',
+              kerb_def_dom => 'MSU.EDU',
+              @_,
+          );
+    my $result='';
+    $result.=<<"END";
+<input type="radio" name="login" value="nochange" checked="checked"
+       onclick="javascript:changed_radio('nochange',$in{'formname'});">
+Do not change login data
+END
+    return $result;
+}
+
+sub authform_kerberos{  
+    my %in = (
+              formname => 'document.cu',
+              kerb_def_dom => 'MSU.EDU',
+              @_,
+              );
+    my $result='';
+    $result.=<<"END";
+<input type="radio" name="login" value="krb" 
+       onclick="javascript:changed_radio('krb',$in{'formname'});"
+       onchange="javascript:changed_radio('krb',$in{'formname'});">
+Kerberos authenticated with domain
+<input type="text" size="10" name="krbarg" value=""
+       onchange="javascript:changed_text('krb',$in{'formname'});">
+END
+    return $result;
+}
+
+sub authform_internal{  
+    my %args = (
+                formname => 'document.cu',
+                kerb_def_dom => 'MSU.EDU',
+                @_,
+                );
+    my $result='';
+    $result.=<<"END";
+<input type="radio" name="login" value="int"
+       onchange="javascript:changed_radio('int',$args{'formname'});"
+       onclick="javascript:changed_radio('int',$args{'formname'});">
+Internally authenticated (with initial password 
+<input type="text" size="10" name="intarg" value=""
+       onchange="javascript:changed_text('int',$args{'formname'});">
+END
+    return $result;
+}
+
+sub authform_local{  
+    my %in = (
+              formname => 'document.cu',
+              kerb_def_dom => 'MSU.EDU',
+              @_,
+              );
+    my $result='';
+    $result.=<<"END";
+<input type="radio" name="login" value="loc"
+       onchange="javascript:changed_radio('loc',$in{'formname'});"
+       onclick="javascript:changed_radio('loc',$in{'formname'});"> 
+Local Authentication with argument
+<input type="text" size="10" name="locarg" value=""
+       onchange="javascript:changed_text('loc',$in{'formname'});">
+END
+    return $result;
+}
+
+sub authform_filesystem{  
+    my %in = (
+              formname => 'document.cu',
+              kerb_def_dom => 'MSU.EDU',
+              @_,
+              );
+    my $result='';
+    $result.=<<"END";
+<input type="radio" name="login" value="fsys" 
+       onchange="javascript:changed_radio('fsys',$in{'formname'});"
+       onclick="javascript:changed_radio('fsys',$in{'formname'});"> 
+Filesystem authenticated (with initial password 
+<input type="text" size="10" name="fsysarg" value=""
+       onchange="javascript:changed_text('fsys',$in{'formname'});">
+END
+    return $result;
+}
+
+###############################################################
+##   End Authentication changing form generation functions   ##
+###############################################################
+
+
+
+# ---------------------------------------------------------- Is this a keyword?
+
+sub keyword {
+    my $newword=shift;
+    $newword=~s/\W//g;
+    $newword=~tr/A-Z/a-z/;
+    my $tindex=$theindex{$newword};
+    if ($tindex) {
+        if ($thecount[$tindex]>$theavecount) {
+           return 1;
+        }
+    }
+    return 0;
+}
+# -------------------------------------------------------- Return related words
+
+sub related {
+    my $newword=shift;
+    $newword=~s/\W//g;
+    $newword=~tr/A-Z/a-z/;
+    my $tindex=$theindex{$newword};
+    if ($tindex) {
+        my %found=();
+        foreach (split(/\,/,$therelated[$tindex])) {
+# - Related word found
+            my ($ridx,$rcount)=split(/\:/,$_);
+# - Direct relation index
+            my $directrel=$rcount/$thecount[$tindex];
+            if ($directrel>$thethreshold) {
+               foreach (split(/\,/,$therelated[$ridx])) {
+                  my ($rridx,$rrcount)=split(/\:/,$_);
+                  if ($rridx==$tindex) {
+# - Determine reverse relation index
+                     my $revrel=$rrcount/$thecount[$ridx];
+# - Calculate full index
+                     $found{$ridx}=$directrel*$revrel;
+                     if ($found{$ridx}>$thethreshold) {
+                        foreach (split(/\,/,$therelated[$ridx])) {
+                            my ($rrridx,$rrrcount)=split(/\:/,$_);
+                            unless ($found{$rrridx}) {
+                               my $revrevrel=$rrrcount/$thecount[$ridx];
+                               if (
+                          $directrel*$revrel*$revrevrel>$thethreshold
+                               ) {
+                                  $found{$rrridx}=
+                                       $directrel*$revrel*$revrevrel;
+                               }
+                            }
+                        }
+                     }
+                  }
+               }
+            }
+        }
+    }
+    return ();
 }
 
 # ---------------------------------------------------------------- Language IDs
 sub languageids {
-
+    return sort(keys(%language));
 }
 
 # -------------------------------------------------------- Language Description
 sub languagedescription {
-
+    return $language{shift(@_)};
 }
 
 # --------------------------------------------------------------- Copyright IDs
 sub copyrightids {
-
+    return sort(keys(%cprtag));
 }
 
 # ------------------------------------------------------- Copyright Description
 sub copyrightdescription {
-
+    return $cprtag{shift(@_)};
 }
 
 # ------------------------------------------------------------- File Categories
 sub filecategories {
+    return sort(keys(%category_extensions));
+}
 
+# -------------------------------------- File Types within a specified category
+sub filecategorytypes {
+    return @{$category_extensions{lc($_[0])}};
 }
 
 # ------------------------------------------------------------------ File Types
 sub fileextensions {
-
+    return sort(keys(%fe));
 }
 
 # ------------------------------------------------------------- Embedding Style
 sub fileembstyle {
-
+    return $fe{lc(shift(@_))};
 }
 
 # ------------------------------------------------------------ Description Text
 sub filedescription {
+    return $fd{lc(shift(@_))};
+}
 
+# ------------------------------------------------------------ Description Text
+sub filedescriptionex {
+    my $ex=shift;
+    return '.'.$ex.' '.$fd{lc($ex)};
 }
 
+# ---- Retrieve attempts by students
+# input
+# $symb             - problem including path
+# $username,$domain - that of the student
+# $course           - course name
+# $getattempt       - leave blank if want all attempts, else put something.
+# 
+# output
+# formatted as a table all the attempts, if any.
+#
 sub get_previous_attempt {
-  my ($symb,$username,$domain,$course)=@_;
+  my ($symb,$username,$domain,$course,$getattempt)=@_;
   my $prevattempts='';
   if ($symb) {
     my (%returnhash)=
@@ -132,37 +878,51 @@ sub get_previous_attempt {
       my %lasthash=();
       my $version;
       for ($version=1;$version<=$returnhash{'version'};$version++) {
-        map {
+        foreach (sort(split(/\:/,$returnhash{$version.':keys'}))) {
 	  $lasthash{$_}=$returnhash{$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{$version.':'.$_}));
+      $prevattempts='<table border="0" width="100%"><tr><td bgcolor="#000000">';
+      $prevattempts.='<table border="0" width="100%"><tr bgcolor="#e6ffff"><td>History</td>';
+      foreach (sort(keys %lasthash)) {
+	my ($ign,@parts) = split(/\./,$_);
+	if ($#parts > 0) {
+	  my $data=$parts[-1];
+	  pop(@parts);
+	  $prevattempts.='<td>Part '.join('.',@parts).'<br />'.$data.'&nbsp;</td>';
+	} else {
+	  if ($#parts == 0) {
+	    $prevattempts.='<th>'.$parts[0].'</th>';
 	  } else {
-	    $value=$returnhash{$version.':'.$_};
+	    $prevattempts.='<th>'.$ign.'</th>';
 	  }
-	  $prevattempts.='<td>'.$value.'</td>';   
-        } sort(keys %lasthash);
+	}
       }
-      $prevattempts.='</tr><tr><th>Current</th>';
-      map {
+      if ($getattempt eq '') {
+	for ($version=1;$version<=$returnhash{'version'};$version++) {
+	  $prevattempts.='</tr><tr bgcolor="#ffffe6"><td>Transaction '.$version.'</td>';
+	    foreach (sort(keys %lasthash)) {
+	       my $value;
+	       if ($_ =~ /timestamp/) {
+		  $value=scalar(localtime($returnhash{$version.':'.$_}));
+	       } else {
+		  $value=$returnhash{$version.':'.$_};
+	       }
+	       $prevattempts.='<td>'.$value.'&nbsp;</td>';   
+	    }
+	 }
+      }
+      $prevattempts.='</tr><tr bgcolor="#ffffe6"><td>Current</td>';
+      foreach (sort(keys %lasthash)) {
 	my $value;
 	if ($_ =~ /timestamp/) {
 	  $value=scalar(localtime($lasthash{$_}));
 	} else {
 	  $value=$lasthash{$_};
 	}
-	$prevattempts.='<td>'.$value.'</td>';
-      } sort(keys %lasthash);
-      $prevattempts.='</tr></table>';
+	$prevattempts.='<td>'.$value.'&nbsp;</td>';
+      }
+      $prevattempts.='</tr></table></td></tr></table>';
     } else {
       $prevattempts='Nothing submitted - no attempts.';
     }
@@ -212,27 +972,30 @@ sub get_student_answers {
   foreach my $element (@elements) {
     $ENV{'form.grade_'.$element}=$old{$element};
   }
-  $userview=~s/\<body[^\>]*\>//gi;
-  $userview=~s/\<\/body\>//gi;
-  $userview=~s/\<html\>//gi;
-  $userview=~s/\<\/html\>//gi;
-  $userview=~s/\<head\>//gi;
-  $userview=~s/\<\/head\>//gi;
-  $userview=~s/action\s*\=/would_be_action\=/gi;
   return $userview;
 }
 
+###############################################
+
+###############################################
+
 sub get_unprocessed_cgi {
-  my ($query)= @_;
-  map {
+  my ($query,$possible_names)= @_;
+  # $Apache::lonxml::debug=1;
+  foreach (split(/&/,$query)) {
     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));
+    $name = &Apache::lonnet::unescape($name);
+    if (!defined($possible_names) || (grep {$_ eq $name} @$possible_names)) {
+      $value =~ tr/+/ /;
+      $value =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C",hex($1))/eg;
+      &Apache::lonxml::debug("Seting :$name: to :$value:");
+      unless (defined($ENV{'form.'.$name})) { &add_to_env('form.'.$name,$value) };
+    }
+  }
 }
 
 sub cacheheader {
+  unless ($ENV{'request.method'} eq 'GET') { return ''; }
   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" />
@@ -242,10 +1005,362 @@ sub cacheheader {
 
 sub no_cache {
   my ($r) = @_;
-  my $date=strftime("%a, %d %b %Y %H:%M:%S GMT",gmtime);
+  unless ($ENV{'request.method'} eq 'GET') { return ''; }
+  #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" => $date);
+  #$r->header_out("Expires" => $date);
+}
+
+sub add_to_env {
+  my ($name,$value)=@_;
+  if (defined($ENV{$name})) {
+    if (ref($ENV{$name})) {
+      #already have multiple values
+      push(@{ $ENV{$name} },$value);
+    } else {
+      #first time seeing multiple values, convert hash entry to an arrayref
+      my $first=$ENV{$name};
+      undef($ENV{$name});
+      push(@{ $ENV{$name} },$first,$value);
+    }
+  } else {
+    $ENV{$name}=$value;
+  }
+}
+
+=pod
+
+=head2 CSV Upload/Handling functions
+
+=over 4
+
+=item  upfile_store($r)
+
+Store uploaded file, $r should be the HTTP Request object,
+needs $ENV{'form.upfile'}
+returns $datatoken to be put into hidden field
+
+=cut
+
+sub upfile_store {
+    my $r=shift;
+    $ENV{'form.upfile'}=~s/\r/\n/gs;
+    $ENV{'form.upfile'}=~s/\f/\n/gs;
+    $ENV{'form.upfile'}=~s/\n+/\n/gs;
+    $ENV{'form.upfile'}=~s/\n+$//gs;
+
+    my $datatoken=$ENV{'user.name'}.'_'.$ENV{'user.domain'}.
+	'_enroll_'.$ENV{'request.course.id'}.'_'.time.'_'.$$;
+    {
+	my $fh=Apache::File->new('>'.$r->dir_config('lonDaemons').
+				 '/tmp/'.$datatoken.'.tmp');
+	print $fh $ENV{'form.upfile'};
+    }
+    return $datatoken;
+}
+
+=item load_tmp_file($r)
+
+Load uploaded file from tmp, $r should be the HTTP Request object,
+needs $ENV{'form.datatoken'},
+sets $ENV{'form.upfile'} to the contents of the file
+
+=cut
+
+sub load_tmp_file {
+    my $r=shift;
+    my @studentdata=();
+    {
+	my $fh;
+	if ($fh=Apache::File->new($r->dir_config('lonDaemons').
+				  '/tmp/'.$ENV{'form.datatoken'}.'.tmp')) {
+	    @studentdata=<$fh>;
+	}
+    }
+    $ENV{'form.upfile'}=join('',@studentdata);
+}
+
+=item upfile_record_sep()
+
+Separate uploaded file into records
+returns array of records,
+needs $ENV{'form.upfile'} and $ENV{'form.upfiletype'}
+
+=cut
+
+sub upfile_record_sep {
+    if ($ENV{'form.upfiletype'} eq 'xml') {
+    } else {
+	return split(/\n/,$ENV{'form.upfile'});
+    }
+}
+
+=item record_sep($record)
+
+Separate a record into fields $record should be an item from the upfile_record_sep(), needs $ENV{'form.upfiletype'}
+
+=cut
+
+sub record_sep {
+    my $record=shift;
+    my %components=();
+    if ($ENV{'form.upfiletype'} eq 'xml') {
+    } elsif ($ENV{'form.upfiletype'} eq 'space') {
+        my $i=0;
+        foreach (split(/\s+/,$record)) {
+            my $field=$_;
+            $field=~s/^(\"|\')//;
+            $field=~s/(\"|\')$//;
+            $components{$i}=$field;
+            $i++;
+        }
+    } elsif ($ENV{'form.upfiletype'} eq 'tab') {
+        my $i=0;
+        foreach (split(/\t+/,$record)) {
+            my $field=$_;
+            $field=~s/^(\"|\')//;
+            $field=~s/(\"|\')$//;
+            $components{$i}=$field;
+            $i++;
+        }
+    } else {
+        my @allfields=split(/\,/,$record);
+        my $i=0;
+        my $j;
+        for ($j=0;$j<=$#allfields;$j++) {
+            my $field=$allfields[$j];
+            if ($field=~/^\s*(\"|\')/) {
+		my $delimiter=$1;
+                while (($field!~/$delimiter$/) && ($j<$#allfields)) {
+		    $j++;
+		    $field.=','.$allfields[$j];
+		}
+                $field=~s/^\s*$delimiter//;
+                $field=~s/$delimiter\s*$//;
+            }
+            $components{$i}=$field;
+	    $i++;
+        }
+    }
+    return %components;
+}
+
+=item upfile_select_html()
+
+return HTML code to select file and specify its type
+
+=cut
+
+sub upfile_select_html {
+    return (<<'ENDUPFORM');
+<input type="file" name="upfile" size="50">
+<br />Type: <select name="upfiletype">
+<option value="csv">CSV (comma separated values, spreadsheet)</option>
+<option value="space">Space separated</option>
+<option value="tab">Tabulator separated</option>
+<option value="xml">HTML/XML</option>
+</select>
+ENDUPFORM
+}
+
+=item csv_print_samples($r,$records)
+
+Prints a table of sample values from each column uploaded $r is an
+Apache Request ref, $records is an arrayref from
+&Apache::loncommon::upfile_record_sep
+
+=cut
+
+sub csv_print_samples {
+    my ($r,$records) = @_;
+    my (%sone,%stwo,%sthree);
+    %sone=&record_sep($$records[0]);
+    if (defined($$records[1])) {%stwo=&record_sep($$records[1]);}
+    if (defined($$records[2])) {%sthree=&record_sep($$records[2]);}
+
+    $r->print('Samples<br /><table border="2"><tr>');
+    foreach (sort({$a <=> $b} keys(%sone))) { $r->print('<th>Column&nbsp;'.($_+1).'</th>'); }
+    $r->print('</tr>');
+    foreach my $hash (\%sone,\%stwo,\%sthree) {
+	$r->print('<tr>');
+	foreach (sort({$a <=> $b} keys(%sone))) {
+	    $r->print('<td>');
+	    if (defined($$hash{$_})) { $r->print($$hash{$_}); }
+	    $r->print('</td>');
+	}
+	$r->print('</tr>');
+    }
+    $r->print('</tr></table><br />'."\n");
+}
+
+=item csv_print_select_table($r,$records,$d)
+
+Prints a table to create associations between values and table columns.
+$r is an Apache Request ref,
+$records is an arrayref from &Apache::loncommon::upfile_record_sep,
+$d is an array of 2 element arrays (internal name, displayed name)
+
+=cut
+
+sub csv_print_select_table {
+    my ($r,$records,$d) = @_;
+    my $i=0;my %sone;
+    %sone=&record_sep($$records[0]);
+    $r->print('Associate columns with student attributes.'."\n".
+	     '<table border="2"><tr><th>Attribute</th><th>Column</th></tr>'."\n");
+    foreach (@$d) {
+	my ($value,$display)=@{ $_ };
+	$r->print('<tr><td>'.$display.'</td>');
+
+	$r->print('<td><select name=f'.$i.
+		  ' onchange="javascript:flip(this.form,'.$i.');">');
+	$r->print('<option value="none"></option>');
+	foreach (sort({$a <=> $b} keys(%sone))) {
+	    $r->print('<option value="'.$_.'">Column '.($_+1).'</option>');
+	}
+	$r->print('</select></td></tr>'."\n");
+	$i++;
+    }
+    $i--;
+    return $i;
+}
+
+=item csv_samples_select_table($r,$records,$d)
+
+Prints a table of sample values from the upload and can make associate samples to internal names.
+
+$r is an Apache Request ref,
+$records is an arrayref from &Apache::loncommon::upfile_record_sep,
+$d is an array of 2 element arrays (internal name, displayed name)
+
+=cut
+
+sub csv_samples_select_table {
+    my ($r,$records,$d) = @_;
+    my %sone; my %stwo; my %sthree;
+    my $i=0;
+
+    $r->print('<table border=2><tr><th>Field</th><th>Samples</th></tr>');
+    %sone=&record_sep($$records[0]);
+    if (defined($$records[1])) {%stwo=&record_sep($$records[1]);}
+    if (defined($$records[2])) {%sthree=&record_sep($$records[2]);}
+
+    foreach (sort keys %sone) {
+	$r->print('<tr><td><select name=f'.$i.
+		  ' onchange="javascript:flip(this.form,'.$i.');">');
+	foreach (@$d) {
+	    my ($value,$display)=@{ $_ };
+	    $r->print('<option value='.$value.'>'.$display.'</option>');
+	}
+	$r->print('</select></td><td>');
+	if (defined($sone{$_})) { $r->print($sone{$_}."</br>\n"); }
+	if (defined($stwo{$_})) { $r->print($stwo{$_}."</br>\n"); }
+	if (defined($sthree{$_})) { $r->print($sthree{$_}."</br>\n"); }
+	$r->print('</td></tr>');
+	$i++;
+    }
+    $i--;
+    return($i);
 }
 1;
 __END__;
+
+=pod
+
+=back
+
+=head2 Access .tab File Data
+
+=over 4
+
+=item languageids() 
+
+returns list of all language ids
+
+=item languagedescription() 
+
+returns description of a specified language id
+
+=item copyrightids() 
+
+returns list of all copyrights
+
+=item copyrightdescription() 
+
+returns description of a specified copyright id
+
+=item filecategories() 
+
+returns list of all file categories
+
+=item filecategorytypes() 
+
+returns list of file types belonging to a given file
+category
+
+=item fileembstyle() 
+
+returns embedding style for a specified file type
+
+=item filedescription() 
+
+returns description for a specified file type
+
+=item filedescriptionex() 
+
+returns description for a specified file type with
+extra formatting
+
+=back
+
+=head2 Alternate Problem Views
+
+=over 4
+
+=item get_previous_attempt() 
+
+return string with previous attempt on problem
+
+=item get_student_view() 
+
+show a snapshot of what student was looking at
+
+=item get_student_answers() 
+
+show a snapshot of how student was answering problem
+
+=back
+
+=head2 HTTP Helper
+
+=over 4
+
+=item get_unprocessed_cgi($query,$possible_names)
+
+Modify the %ENV hash to contain unprocessed CGI form parameters held in
+$query.  The parameters listed in $possible_names (an array reference),
+will be set in $ENV{'form.name'} if they do not already exist.
+
+Typically called with $ENV{'QUERY_STRING'} as the first parameter.  
+$possible_names is an ref to an array of form element names.  As an example:
+get_unprocessed_cgi($ENV{'QUERY_STRING'},['uname','udom']);
+will result in $ENV{'form.uname'} and $ENV{'form.udom'} being set.
+
+=item cacheheader() 
+
+returns cache-controlling header code
+
+=item nocache() 
+
+specifies header code to not have cache
+
+=item add_to_env($name,$value) 
+
+adds $name to the %ENV hash with value
+$value, if $name already exists, the entry is converted to an array
+reference and $value is added to the array.
+
+=back
+
+=cut