#
# Copyright Michigan State University Board of Trustees
#
# This file is part of the LearningOnline Network with CAPA (LON-CAPA).
#
# LON-CAPA is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# LON-CAPA is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with LON-CAPA; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#
# /home/httpd/html/adm/gpl.txt
#
# http://www.lon-capa.org/
#

package Apache::coursecatalog;

use strict;
use lib qw(/home/httpd/lib/perl);
use Apache::Constants qw(:common);
use Apache::loncommon;
use Apache::lonhtmlcommon;
use Apache::lonnet;
use Apache::lonlocal;
use Apache::courseclassifier;
use Apache::lonacc;
use LONCAPA;

sub handler {
    my ($r) = @_;
    &Apache::loncommon::content_type($r,'text/html');
    $r->send_http_header;
    if ($r->header_only) {
        return OK;
    }
    my %cookies=CGI::Cookie->parse($r->header_in('Cookie'));
    my $lonid=$cookies{'lonID'};
    my $lonidsdir=$r->dir_config('lonIDsDir');
    my $handle;
    if ($lonid) {
	$handle=&LONCAPA::clean_handle($lonid->value);
    }
    if ((-e "$lonidsdir/$handle.id") && ($handle ne '')) {
        &Apache::lonnet::transfer_profile_to_env($lonidsdir,$handle);
    }
    &Apache::lonacc::get_posted_cgi($r);
    &Apache::lonlocal::get_language_handle($r);
    &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'},['sortby']);
    my $codedom = $Apache::lonnet::perlvar{'lonDefDomain'};
    my $formname = 'coursecatalog';
    my $domdesc = $Apache::lonnet::domaindescription{$codedom};

    &Apache::lonhtmlcommon::clear_breadcrumbs();
    if ($env{'form.coursenum'} ne '' && &user_is_known()) {
        &course_details($r,$codedom,$formname,$domdesc);
    } else {
        &course_selector($r,$codedom,$formname,$domdesc);
        if ($env{'form.state'} eq 'listing') {
            $r->print('<br /><br />'.&print_course_listing($codedom).'<br />');
        } 
    }
    $r->print(&Apache::loncommon::end_page());
    return OK;
}

sub course_details {
    my ($r,$codedom,$formname,$domdesc) = @_;
    my $output;
    my %add_entries = (topmargin    => "0",
                       marginheight => "0",);
    my $start_page =
        &Apache::loncommon::start_page('Course Catalog','',
                                           {
                                             'add_entries' => \%add_entries,
                                             'no_inline_link'   => 1,});
    $r->print($start_page);
    &Apache::lonhtmlcommon::add_breadcrumb
            ({href=>"/adm/coursecatalog",
              text=>"Select courses"},
             {href=>"javascript:document.$formname.submit()",
              text=>"Course listing"},
             {text=>"Course details"});
    $r->print(&Apache::lonhtmlcommon::breadcrumbs('Course Details'));
    $r->print('<br />'.&mt('Detailed course information:').'<br /><br />'.
              '<form name="coursecatalog" method="post">'.
              &print_course_listing($codedom).'<br /><br />');
    $r->print('<a href = "javascript:document.coursecatalog.submit()">'.
              &mt('Back to course listing').'</a>'.
              '<input type="hidden" name="sortby" value="'.
              $env{'form.sortby'}.'" />'.
              '<input type="hidden" name="state" value="listing" /></form>');
}

sub course_selector {
    my ($r,$codedom,$formname,$domdesc) = @_;
    my %coursecodes = ();
    my %codes = ();
    my @codetitles = ();
    my %cat_titles = ();
    my %cat_order = ();
    my %idlist = ();
    my %idnums = ();
    my %idlist_titles = ();
    my %by_year;
    my %by_sem;
    my %by_dept;
    my %cat_items;
    my $caller = 'global';
    my $format_reply;
    my $totcodes = 0;
    my $jscript = '';
    my ($numtitles,$lasttitle);
    $totcodes = &Apache::courseclassifier::retrieve_instcodes(\%coursecodes,$codedom,$totcodes);
    if ($totcodes > 0) {
        $format_reply = &Apache::lonnet::auto_instcode_format($caller,$codedom,\%coursecodes,\%codes,\@codetitles,\%cat_titles,\%cat_order);
        if ($format_reply eq 'ok') {
            my $numtypes = @codetitles;
            &Apache::courseclassifier::build_code_selections(\%codes,\@codetitles,\%cat_titles,\%cat_order,\%idlist,\%idnums,\%idlist_titles);
            my ($scripttext,$longtitles) = &Apache::courseclassifier::javascript_definitions(\@codetitles,\%idlist,\%idlist_titles,\%idnums,\%cat_titles);
            my $longtitles_str = join('","',@{$longtitles});
            my $allidlist = $idlist{$codetitles[0]};
            $numtitles = @codetitles;
            $lasttitle = $numtitles;
            if ($numtitles > 4) {
                $lasttitle = 4;
            }
            my @data = ('top');
            for (my $k=0; $k<$lasttitle; $k++) {
                my $cat = $codetitles[$k];
                my $level = 1;
                $level = &recurse_options($codetitles[$k],$idlist{$codetitles[$k]},$level,$cat,\%cat_items,\@data,\%by_year,\%by_sem,\%by_dept);     }
            $scripttext .= &build_javascript(\%by_year,\%by_sem,\%by_dept,\%cat_order,\@codetitles);
            $jscript .= &javascript_select_filler($formname,$scripttext,\@codetitles,$longtitles_str,$allidlist);
        }
        if ($env{'form.state'} eq 'listing') {
            $jscript .= '
function setElements() {
';
            for (my $i=0; $i<@codetitles-1; $i++) {
                if ($env{'form.'.$codetitles[$i]} != -1) {
                    $jscript .= '
    for (var j=0; j<document.'.$formname.'.'.$codetitles[$i].'.length; j++) {
        if (document.'.$formname.'.'.$codetitles[$i].'[j].value == "'.$env{'form.'.$codetitles[$i]}.'") {
            document.'.$formname.'.'.$codetitles[$i].'.selectedIndex = j;
        }
    }
';
                }
            }
            $jscript .= '   courseSet()'."\n";
            if ($env{'form.'.$codetitles[-1]} != -1) {
                $jscript .= '
    for (var j=0; j<document.'.$formname.'.'.$codetitles[-1].'.length; j++) {
        if (document.'.$formname.'.'.$codetitles[-1].'[j].value == "'.$env{'form.'.$codetitles[-1]}.'") {
            document.'.$formname.'.'.$codetitles[-1].'.selectedIndex = j;
        }
    }
';
            }
            $jscript .= '}';
            $jscript .= qq|
function changeSort(caller) {
    document.$formname.sortby.value = caller;
    document.$formname.submit();
}
function setCourseId(caller) {
   document.$formname.coursenum.value = caller;
   document.$formname.submit(); 
}\n|;
        }
        my $js = '<script type"text/javascript">'."\n$jscript\n".
                 '</script>';
        my %add_entries = (topmargin    => "0",
                           marginheight => "0",);
        if ($env{'form.state'} eq 'listing') {
            $add_entries{'onLoad'} = 'setElements()';
        }
        my $start_page =
            &Apache::loncommon::start_page('Course Catalog',$js,
                                           {
                                             'add_entries' => \%add_entries,
                                             'no_inline_link'   => 1,});
        $r->print($start_page);
        if ($env{'form.state'} eq 'listing') {
            &Apache::lonhtmlcommon::add_breadcrumb
            ({href=>"/adm/coursecatalog",
              text=>"Select courses"},
             {text=>"Course listing"});
             $r->print(&Apache::lonhtmlcommon::breadcrumbs('Course Listing'));
        } else {
            &Apache::lonhtmlcommon::add_breadcrumb
            ({href=>"/adm/coursecatalog",
              text=>"Select courses"});
            $r->print(&Apache::lonhtmlcommon::breadcrumbs('Select courses'));
        }
        $r->print('<h3>'.&mt('Display information about official [_1] classes for which LON-CAPA courses have been created:',$domdesc).'</h3>');
        $r->print(&mt('<b>Choose which course(s) to list.</b><br />'));
        $r->print('<form name="coursecatalog" method="post">');
        if ($numtitles > 0) {
            $r->print('<table><tr>');
            for (my $k=0; $k<$lasttitle-1; $k++) {
                my @unsorted = @{$cat_items{$codetitles[$k]}};
                my @items;
                &Apache::courseclassifier::sort_cats($k,\%cat_order,\@codetitles,\@unsorted,\@items);
                my @longitems;
                if (defined($cat_titles{$codetitles[$k]})) {
                    foreach my $item (@items) {
                        push(@longitems,$cat_titles{$codetitles[$k]}{$item});
                    }
                } else {
                    @longitems = @items;
                }
                $r->print('<td align="center">'.$codetitles[$k].'<br />'."\n".
                          '<select name="'.$codetitles[$k].'" onChange="courseSet()"');
                $r->print('>'."\n".'<option value="0" />All'."\n");
                for (my $i=0; $i<@items; $i++) {
                    if ($longitems[$i] eq '') {
                        $longitems[$i] = $items[$i];
                    }
                    $r->print(' <option value="'.$items[$i].'">'.$longitems[$i].'</option>');
                }
                $r->print('</select></td>');
            }
            $r->print('<td align="center">'.$codetitles[$lasttitle-1].'<br />'."\n".
                      '<select name="'.$codetitles[$lasttitle-1].'">'."\n".
                      '<option value="0">All'."\n".
                      '</option>'."\n".'</select>'."\n".
                 '</td>'
                );
            if (&user_is_dc($codedom)) {
                my $showdetails_status;
                if ($env{'form.showdetails'}) {
                    $showdetails_status = 'checked="checked" ';
                } 
                $r->print('<td></td><td><input type="checkbox" name="showdetails" value="1" '.$showdetails_status.'/>'.&mt('Show full details for each course (DC only)').'</td>');
            }
            $r->print('</tr></table>');
            if ($numtitles > 4) {
                $r->print('<br /><br />'.$codetitles[$numtitles-1].'<br />'."\n".
                '<input type="text" name="'.$codetitles[$numtitles-1].'" /><br />'."\n");
            }
        }
        $r->print('<br /><input type="hidden" name="coursenum" value="" /><input type="hidden" name="state" value="listing" /><input type="hidden" name="sortby" value="" /><input type="submit" name="catalogfilter" value="'.&mt('Display courses').'" /></form>');
    } else {
        $r->print(&Apache::loncommon::start_page('Course Catalog','',
                  {
                   'no_inline_link'   => 1,}));
        $r->print('<br />'.&mt('No official courses to display for [_1].',$domdesc));
    }
    return;
}

sub user_is_dc {
    my ($codedom) = @_;
    if (exists($env{'user.role.dc./'.$codedom.'/'})) {
        my $livedc = 1;
        my $now = time;
        my ($start,$end)=split(/\./,$env{'user.role.dc./'.$codedom.'/'});
        if ($start && $start>$now) { $livedc = 0; }
        if ($end   && $end  <$now) { $livedc = 0; }
        return $livedc;
    }
    return;
}

sub recurse_options {
    my ($currkey,$currlist,$level,$cat,$cat_options,$data,$by_year,$by_sem,$by_dept) = @_;
    if (ref($currlist) eq 'HASH') {
        $level ++;
        foreach my $key (sort(keys(%{$currlist}))) {
            $$data[$level-1]= $key;
            &recurse_options($key,$currlist->{$key},$level,$cat,$cat_options,$data,$by_year,$by_sem,$by_dept);
        }
    } else {
        $level --;
        my @contents = split(/","/,$currlist);
        foreach my $item (@contents) {
            if (!grep(/^\Q$item\E$/,@{$cat_options->{$cat}})) {
                push(@{$cat_options->{$cat}},$item);
            }
            if ($level == 3) {
                if (!grep/^\Q$item\E$/,@{$by_year->{$data->[1]}->{$currkey}}) {
                    push(@{$by_year->{$data->[1]}->{$currkey}},$item);                 
                }
                if (!grep/^\Q$item\E$/,@{$by_sem->{$data->[2]}->{$currkey}}) {
                    push(@{$by_sem->{$data->[2]}->{$currkey}},$item);
                }
                if (!grep/^\Q$item\E$/,@{$by_dept->{$currkey}}) {
                    push(@{$by_dept->{$currkey}},$item);
                }

            }
        }
    }
    return $level;
}

sub build_javascript {
    my ($by_year,$by_sem,$by_dept,$cat_order,$codetitles) = @_;
    my @unsorted = keys(%{$by_year});
    my @sorted_yrs; 
    &Apache::courseclassifier::sort_cats('0',$cat_order,$codetitles,\@unsorted,\@sorted_yrs);
    my $output = 'var idcse_by_yr_year = new Array("'.join('","',@sorted_yrs).'");'."\n".
                 'var idcse_by_yr_dept = new Array('.scalar(@sorted_yrs).');'."\n".
                 'var idcse_by_yr_num = new Array('.scalar(@sorted_yrs).');'."\n";
    for (my $i=0; $i<@sorted_yrs; $i++) {
        my $numkeys = keys(%{$by_year->{$sorted_yrs[$i]}});
        $output .= " idcse_by_yr_num[$i] = new Array($numkeys);\n";
        if (ref($by_year->{$sorted_yrs[$i]}) eq 'HASH') {
            @unsorted = keys(%{$by_year->{$sorted_yrs[$i]}});
            my @sorted_depts;
            &Apache::courseclassifier::sort_cats('2',$cat_order,$codetitles,\@unsorted,\@sorted_depts);
            $output .= qq| idcse_by_yr_dept[$i] = new Array ("|.join('","',@sorted_depts).'");'."\n";
            for (my $j=0; $j<@sorted_depts; $j++) {
                $output .= qq| idcse_by_yr_num[$i][$j] = new Array ("|;
                $output .= join('","',sort(@{$by_year->{$sorted_yrs[$i]}->{$sorted_depts[$j]}})).'");'."\n";
            }
        }
    }
    @unsorted = keys(%{$by_sem});
    my @sorted_sems;
    &Apache::courseclassifier::sort_cats('1',$cat_order,$codetitles,\@unsorted,\@sorted_sems);
    $output .=  'idcse_by_sem_sems = new Array("'.join('","',@sorted_sems).'");'."\n".
                'idcse_by_sem_dept = new Array('.scalar(@sorted_sems).');'."\n".
                'idcse_by_sem_num = new Array('.scalar(@sorted_sems).');'."\n";
    for (my $i=0; $i<@sorted_sems; $i++) {
        my $numkeys = keys(%{$by_sem->{$sorted_sems[$i]}});
        $output .= " idcse_by_sem_num[$i] = new Array($numkeys);\n";
        if (ref($by_sem->{$sorted_sems[$i]}) eq 'HASH') {
            @unsorted = keys(%{$by_sem->{$sorted_sems[$i]}});
            my @sorted_depts;
            &Apache::courseclassifier::sort_cats('2',$cat_order,$codetitles,\@unsorted,\@sorted_depts);
            $output .= qq| idcse_by_sem_dept[$i] = new Array("|.join('","',@sorted_depts).'");'."\n";
            for (my $j=0; $j<@sorted_depts; $j++) {
                $output .= qq| idcse_by_sem_num[$i][$j] = new Array ("|.join('","',sort(@{$by_sem->{$sorted_sems[$i]}->{$sorted_depts[$j]}})).'");'."\n";
            }
        }
    }
    @unsorted = keys(%{$by_dept});
    my @sorted_deps;
    &Apache::courseclassifier::sort_cats('2',$cat_order,$codetitles,\@unsorted,\@sorted_deps);
    $output .= 'idcse_by_dep = new Array('.scalar(@sorted_deps).');'."\n"; 
    for (my $k=0; $k<@sorted_deps; $k++) {
        $output .= qq| idcse_by_dep[$k] = new Array ("|.join('","',sort(@{$by_dept->{$sorted_deps[$k]}})).'");'."\n";
    }
    return $output;
}

sub search_courselist {
    my ($domain) = @_;
    my ($instcode,%codedefaults,@code_order);
    my $defaults_result = 
        &Apache::lonnet::auto_instcode_defaults($domain,\%codedefaults,
                                               \@code_order);
    if ($defaults_result eq 'ok') {
        $instcode ='^';
        foreach my $item (@code_order) {
            if ($env{'form.'.$item} eq '0' ) {
                $instcode .= $codedefaults{$item}; 
            } else {
                $instcode .= $env{'form.'.$item};
            }
        }
        $instcode .= '$';
    } else {
        $instcode = '.';
    }
    my %courses = &Apache::lonnet::courseiddump($domain,'.',1,$instcode,'.','.',
                                                undef,undef,'Course',1);
    return %courses;
}


sub print_course_listing {
    my ($domain) = @_;
    my $output;
    my %courses;
    my $knownuser = &user_is_known();
    my $details = $env{'form.coursenum'};
    if (&user_is_dc($domain)) {
        if ($env{'form.showdetails'}) {
            $details = 1;
        }
    }
    if ($env{'form.coursenum'} ne '') {
        %courses = &Apache::lonnet::courseiddump($domain,'.',1,'.','.',
                                                 $env{'form.coursenum'},
                                                 undef,undef,'Course');
        if (keys(%courses) == 0) {
            $output .= &mt('The courseID provided does not match a course in this domain.');
            return $output;
        }
    } else {
        %courses = &search_courselist($domain);
        if (keys(%courses) == 0) {
            $output = &mt('No courses match the criteria you selected.');
            return $output;
        }
        if ($knownuser && !$env{'form.showdetails'}) {
            $output = &mt('<b>Note for students:</b> If you are officially enrolled in a course but the course is not listed in your LON-CAPA courses, click the "Show more details" link for the specific course and check the default access dates and/or automated enrollment settings.<br /><br />');
        }
    }
    $output .= &construct_data_table($knownuser,\%courses,$details);
    $output .= &Apache::lonhtmlcommon::echo_form_input(['coursenum','state','catalogfilter','sortby','showdetails']);
    return $output;
}

sub construct_data_table {
    my ($knownuser,$courses,$details,$usersections) = @_;
    my %sortname;
    if (($details eq '') || ($env{'form.showdetails'})) {
        $sortname{'Code'} = 'code';
        $sortname{'Title'} = 'title';
        $sortname{'Owner'} = 'owner';
    }
    my $output = &Apache::loncommon::start_data_table().
                 &Apache::loncommon::start_data_table_header_row();
    my @coltitles = ('Code','Sections','Crosslisted','Title','Owner');
    if (ref($usersections) eq 'HASH') {
       $coltitles[1] = 'Your Section';
    }
    foreach my $item (@coltitles) {
        $output .= '<th>';
        if (defined($sortname{$item})) {
            $output .= '<a href="javascript:changeSort('."'$sortname{$item}'".')">'.&mt($item).'</a>';
        } else {
            $output .= &mt($item);
        }
        $output .= '</th>';
    }
    if ($knownuser) {
        if ($details) {
            $output .=
              '<th>'.&mt('Default Access Dates for Students').'</th>'.
              '<th>'.&mt('Student Counts').'</th>'.
              '<th>'.&mt('Auto-enrollment of <br />registered students').'</th>';
        } else {
            $output .= '<th>&nbsp;</th>';
        }
    }
    &Apache::loncommon::end_data_table_header_row();
    my %courseinfo = &build_courseinfo_hash($courses,$knownuser,$details,
                                            $usersections);
    my %Sortby;
    foreach my $course (sort(keys(%{$courses}))) {
        if ($env{'form.sortby'} eq 'code') {
            push(@{$Sortby{$courseinfo{$course}{'code'}}},$course);
        } elsif ($env{'form.sortby'} eq 'owner') {
            push(@{$Sortby{$courseinfo{$course}{'ownerlastname'}}},$course);
        } else {
            push(@{$Sortby{$courseinfo{$course}{'title'}}},$course);
        }
    }
    my @sorted_courses;
    if (($env{'form.sortby'} eq 'code') || ($env{'form.sortby'} eq 'owner')) {
        @sorted_courses = sort(keys(%Sortby));
    } else {
        @sorted_courses = sort { lc($a) cmp lc($b) } (keys(%Sortby));
    }
    foreach my $item (@sorted_courses) {
        foreach my $course (@{$Sortby{$item}}) {
            $output.=&Apache::loncommon::start_data_table_row(); 
            $output.=&courseinfo_row($courseinfo{$course},$knownuser,$details);
            $output.=&Apache::loncommon::end_data_table_row();
        }
    }
    $output .= &Apache::loncommon::end_data_table();
    return $output;
}

sub build_courseinfo_hash {
    my ($courses,$knownuser,$details,$usersections) = @_;
    my %courseinfo;
    my $now = time;
    foreach my $course (keys(%{$courses})) {
        my $descr;
        if ($courses->{$course} =~ m/^([^:]*):/i) {
            $descr = &unescape($1);
        } else {
            $descr = &unescape($courses->{$course});
        }
        my $cleandesc=&HTML::Entities::encode($descr,'<>&"');
        $cleandesc=~s/'/\\'/g;
        $cleandesc =~ s/^\s+//;
        my ($cdom,$cnum)=split(/\_/,$course);

        my ($desc,$instcode,$owner,$ttype) = split(/:/,$courses->{$course});
        $owner = &unescape($owner);
        my ($ownername,$ownerdom);
        if ($owner =~ /:/) {
            ($ownername,$ownerdom) = split(/:/,$owner);
        } else {
            $ownername = $owner;
            if ($owner ne '') {
                $ownerdom = $cdom;
            }
        }
        my %ownernames;
        if ($ownername ne '' && $ownerdom ne '') {
            %ownernames = &Apache::loncommon::getnames($ownername,$ownerdom);
        }
        $courseinfo{$course}{'cdom'} = $cdom;
        $courseinfo{$course}{'cnum'} = $cnum;
        $courseinfo{$course}{'code'} = $instcode;
        $courseinfo{$course}{'ownerlastname'} = $ownernames{'lastname'};
        $courseinfo{$course}{'title'} = $cleandesc;
        $courseinfo{$course}{'owner'} = $owner;

        my %coursehash = &Apache::lonnet::dump('environment',$cdom,$cnum);
        my @classids;
        my @crosslistings;
        my ($seclist,$numsec) = 
            &identify_sections($coursehash{'internal.sectionnums'});
        if (ref($usersections) eq 'HASH') {
            if (ref($usersections->{$course}) eq 'ARRAY') {
                $seclist = join(', ',@{$usersections->{$course}});
            }
        }
        $courseinfo{$course}{'seclist'} = $seclist;
        my ($xlist_items,$numxlist) = 
            &identify_sections($coursehash{'internal.crosslistings'});
        my $showsyllabus = 1; # default is to include a syllabus link
        if (defined($coursehash{'showsyllabus'})) {
            $showsyllabus = $coursehash{'showsyllabus'};
        }
        $courseinfo{$course}{'showsyllabus'} = $showsyllabus;
        if (((defined($env{'form.coursenum'}) && ($cnum eq $env{'form.coursenum'}))) ||
            ($knownuser && ($details == 1))) {  
            $courseinfo{$course}{'counts'} =  &count_students($cdom,$cnum,$numsec);
            $courseinfo{$course}{'autoenrollment'} =
                &autoenroll_info(\%coursehash,$now,$seclist,$xlist_items,
                                 $instcode,$owner,$cdom,$cnum);

            my $startaccess = '';
            my $endaccess = '';
            my $accessdates;
            if ( defined($coursehash{'default_enrollment_start_date'}) ) {
                $startaccess = &Apache::lonlocal::locallocaltime($coursehash{'default_enrollment_start_date'});
            }
            if ( defined($coursehash{'default_enrollment_end_date'}) ) {
                $endaccess = &Apache::lonlocal::locallocaltime($coursehash{'default_enrollment_end_date'});
                if ($coursehash{'default_enrollment_end_date'} == 0) {
                    $endaccess = "No ending date";
                }
            }
            if ($startaccess) {
                $accessdates .= &mt('<i>From:</i> ').$startaccess.'<br />';
            }
            if ($endaccess) {
                $accessdates .= &mt('<i>To:</i> ').$endaccess.'<br />';
            }
            $courseinfo{$course}{'access'} = $accessdates;
        }
        if ($xlist_items eq '') {
            $xlist_items = &mt('No');
        }
        $courseinfo{$course}{'xlist'} = $xlist_items;
    }
    return %courseinfo;
}

sub count_students {
    my ($cdom,$cnum,$numsec) = @_;
    my $classlist = &Apache::loncoursedata::get_classlist($cdom,$cnum);
    my %student_count = (
                           Active => 0,
                           Future => 0,
                           Expired => 0,
                       );
    my %idx;
    $idx{'status'} = &Apache::loncoursedata::CL_STATUS();
    my %status_title = &Apache::lonlocal::texthash(
                           Expired => 'Previous access',
                           Active => 'Current access',
                           Future => 'Future access',
                       );

    while (my ($student,$data) = each(%$classlist)) {
        $student_count{$data->[$idx{'status'}]} ++;
    }

    my $countslist = &mt('[quant,_1,section]',$numsec).':<br />';
    foreach my $status ('Active','Future') {
        $countslist .= '<nobr>'.$status_title{$status}.': '.
                       $student_count{$status}.'</nobr><br />';
    }
    return $countslist;
}

sub courseinfo_row {
    my ($info,$knownuser,$details) = @_;
    my ($cdom,$cnum,$title,$ownerlast,$code,$owner,$seclist,$xlist_items,
        $accessdates,$showsyllabus,$counts,$autoenrollment,$output);
    if (ref($info) eq 'HASH') {
        $cdom = $info->{'cdom'};
        $cnum = $info->{'cnum'};
        $title = $info->{'title'};
        $ownerlast = $info->{'ownerlastname'};
        $code = $info->{'code'};
        $owner = $info->{'owner'};
        $seclist = $info->{'seclist'};
        $xlist_items = $info->{'xlist'};
        $accessdates = $info->{'access'};
        $counts = $info->{'counts'};
        $autoenrollment = $info->{'autoenrollment'};
        $showsyllabus = $info->{'showsyllabus'};
    } else {
        $output = '<td colspan="8">'.&mt('No information available for [_1].',
                                         $code).'</td>';
        return $output;
    }
    $output .= '<td>'.$code.'</td>'.
               '<td>'.$seclist.'</td>'.
               '<td>'.$xlist_items.'</td>'.
               '<td>'.$title.'&nbsp;<font size="-2">';
    if ($showsyllabus) {
        $output .= &Apache::loncommon::syllabuswrapper(&mt('Syllabus'),$cnum,$cdom);
    } else {
        $output .= '&nbsp;';
    }
    $output .= '</font></td>'.
               '<td>'.$ownerlast.'</td>';
    if ($knownuser) {
        if ($details) {
            $output .=
               '<td>'.$accessdates.'</td>'. 
               '<td>'.$counts.'</td>'.
               '<td>'.$autoenrollment.'</td>';
        } else {
            $output .= "<td><a href=\"javascript:setCourseId('$cnum')\">".&mt('Show more details').'</a></td>';
        }
    }
    return $output;
}

sub identify_sections {
    my ($seclist) = @_;
    my @secnums;
    if ($seclist =~ /,/) {
        my @sections = split(/,/,$seclist);
        foreach my $sec (@sections) {
            $sec =~ s/:[^:]*$//;
            push(@secnums,$sec);
        }
    } else {
        if ($seclist =~ m/^([^:]+):/) {
            my $sec = $1;
            if (!grep(/^\Q$sec\E$/,@secnums)) {
                push(@secnums,$sec);
            }
        }
    }
    @secnums = sort {$a <=> $b} @secnums;
    my $seclist = join(', ',@secnums);
    my $numsec = @secnums;
    return ($seclist,$numsec);
}

sub get_valid_classes {
    my ($seclist,$xlist_items,$crscode,$owner,$cdom,$cnum) = @_;
    my $response;
    my %validations;
    @{$validations{'sections'}} = ();
    @{$validations{'xlists'}} = ();
    my $totalitems = 0;
    if ($seclist) {
        foreach my $sec (split(/, /,$seclist)) {
            my $class = $crscode.$sec;
            if (&Apache::lonnet::auto_validate_class_sec($cdom,$cnum,$owner,
							 $class) eq 'ok') {
                if (!grep(/^\Q$sec$\E/,@{$validations{'sections'}})) {
                    push(@{$validations{'sections'}},$sec);
                    $totalitems ++;
                }
            }
        }
    }
    if ($xlist_items) {
        foreach my $item (split(/, /,$xlist_items)) {
            if (&Apache::lonnet::auto_validate_class_sec($cdom,$cnum,$owner,
							 $item) eq 'ok') {
                if (!grep(/^\Q$item$\E/,@{$validations{'xlists'}})) {
                    push(@{$validations{'xlists'}},$item);
                    $totalitems ++;
                }
            }
        }
    }
    if ($totalitems > 0) {
        if (@{$validations{'sections'}}) {
            $response = &mt('Sections: ').
                        join(', ',@{$validations{'sections'}}).'<br />';
        }
        if (@{$validations{'xlists'}}) {
            $response .= &mt('Courses: ').
                        join(', ',@{$validations{'xlists'}});
        }
    }
    return $response;
}

sub javascript_select_filler {
    my ($formname,$scripttext,$codetitles,$longtitles_str,$allidlist) = @_;
    my $output = <<END;
function courseSet() {
    var longtitles = new Array ("$longtitles_str");
    var valyr = document.$formname.Year.options[document.$formname.Year.selectedIndex].value
    var valsem  = document.$formname.Semester.options[document.$formname.Semester.selectedIndex].value
    var valdept = document.$formname.Department.options[document.$formname.Department.selectedIndex].value
    var valclass = document.$formname.Number.options[document.$formname.Number.selectedIndex].value
    var idyears = new Array("$allidlist");
    var idyr = -1;
    var idsem = -1;
    var iddept = -1;
    document.$formname.Number.length = 0;

    $scripttext

    selYear = document.$formname.Year.selectedIndex-1;
    selSemester = document.$formname.Semester.selectedIndex-1;
    selDepartment = document.$formname.Department.selectedIndex-1;
    if (selYear == -1) {
        if (selSemester == -1) {
            if (selDepartment > -1) {
                document.$formname.Number.options[0] =  new Option('All','0',false,false);
                for (var k=0; k<idcse_by_dep[selDepartment].length; k++) {
                    document.$formname.Number.options[k+1] = new Option(idcse_by_dep[selDepartment][k],idcse_by_dep[selDepartment][k],false,false);

                }
            } 
            else {
                document.$formname.Number.options[0] = new Option("All","0",true,true);
            }
        }
        else {
            if (selDepartment > -1) {
                for (var i=0; i<idcse_by_sem_sems.length; i++) {
                    if (idcse_by_sem_sems[i] == valsem) {
                        idsem = i;
                    }
                }
                if (idsem != -1) {
                    for (var i=0; i<idcse_by_sem_dept[idsem].length; i++) {
                        if (idcse_by_sem_dept[idsem][i] == valdept) {
                            iddept = i;
                        }
                    }
                }
                if (iddept != -1) {
                    document.$formname.Number.options[0] =  new Option('All','0',false,false);
                    for (var k=0; k<idcse_by_sem_num[idsem][iddept].length; k++) {
                        document.$formname.Number.options[k+1] = new Option(idcse_by_sem_num[idsem][iddept][k],idcse_by_sem_num[idsem][iddept][k],false,false);
                    }
                }
                else {
                    document.$formname.Number.options[0] =  new Option('No courses','0',true,true);
                }
            }
            else {
                document.$formname.Number.options[0] = new Option("All","0",true,true);
            }
        }
    }
    else {
        if (selSemester == -1) {
            if (selDepartment > -1) {
                for (var i=0; i<idcse_by_yr_year.length; i++) {
                    if (idcse_by_yr_year[i] == valyr) {
                        idyr = i;
                    }
                }
                if (idyr != -1) {      
                    for (var i=0; i<idcse_by_yr_dept[idyr].length; i++) {
                        if (idcse_by_yr_dept[idyr][i] == valdept) {
                            iddept = i;
                        }
                    }
                }
                if (iddept != -1) {
                    document.$formname.Number.options[0] =  new Option('All','0',false,false);
                    for (var k=0; k<idcse_by_yr_num[idyr][iddept].length; k++) {
                        document.$formname.Number.options[k+1] = new Option(idcse_by_yr_num[idyr][iddept][k],idcse_by_yr_num[idyr][iddept][k],false,false);
                    }
                } 
                else {
                    document.$formname.Number.options[0] =  new Option('No courses','0',true,true);
                }
            }
            else {
                document.$formname.Number.options[0] = new Option("All","0",true,true);
            }
        }
        else {
            if (selDepartment > -1) {
                for (var k=0; k<idyears.length; k++) {
                    if (idyears[k] == valyr) {
                        idyr = k;
                    }
                }
                if (idyr != -1) {
                    for (var k=0; k<idsems[idyr].length; k++) {
                        if (idsems[idyr][k] == valsem) {
                            idsem = k;
                        }
                    }
                }
                if (idsem != -1) {
                    for (var k=0; k<idcodes[idyr][idsem].length; k++) {
                        if (idcodes[idyr][idsem][k] == valdept) {
                            iddept = k;
                        }
                    }
                }
                if (iddept != -1) {
                    document.$formname.Number.options[0] =  new Option('All','0',false,false);
                    for (var i=0; i<idcourses[idyr][idsem][iddept].length; i++) {
                        var display = idcourses[idyr][idsem][iddept][i];
                        if (longtitles[3] == 1) {
                            if (idcourseslongs[idyr][idsem][iddept][i] != "") {
                                display = idcourseslongs[idyr][idsem][iddept][i]
                            }
                        }
                        document.$formname.Number.options[i+1] = new Option(display,idcourses[idyr][idsem][iddept][i],false,false)
                    }
                } 
                else {
                    document.$formname.Number.options[0] =  new Option('No courses','0',true,true);
                }
            } 
            else {
                document.$formname.Number.options[0] =  new Option('All','0',true,true);
            }
        }
        document.$formname.Number.selectedIndex = 0
    }
}
END
    return $output;
}

sub autoenroll_info {
    my ($coursehash,$now,$seclist,$xlist_items,$code,$owner,$cdom,$cnum) = @_;
    my $autoenrolldates = &mt('Not enabled');
    if (defined($coursehash->{'internal.autoadds'}) && $coursehash->{'internal.autoadds'} == 1) {
        my ($autostart,$autoend);
        if ( defined($coursehash->{'internal.autostart'}) ) {
            $autostart = &Apache::lonlocal::locallocaltime($coursehash->{'internal.autostart'});
        }
        if ( defined($coursehash->{'internal.autoend'}) ) {
            $autoend = &Apache::lonlocal::locallocaltime($coursehash->{'internal.autoend'});
        }
        if ($coursehash->{'internal.autostart'} > $now) {
            if ($coursehash->{'internal.autoend'} && $coursehash->{'internal.autoend'} < $now) {
                $autoenrolldates = &mt('Not enabled');
            } else {
                my $valid_classes = 
                   &get_valid_classes($seclist,$xlist_items,$code,
                                      $owner,$cdom,$cnum);
                if ($valid_classes ne '') {
                    $autoenrolldates = &mt('Not enabled<br />Starts: ').
                                       $autostart.'<br />'.$valid_classes;                }
            }
        } else {
            if ($coursehash->{'internal.autoend'} && $coursehash->{'internal.autoend'} < $now) {
                $autoenrolldates = &mt('Not enabled<br />Ended: ').$autoend;
            } else {
                my $valid_classes = &get_valid_classes($seclist,$xlist_items,
                                                       $code,$owner,$cdom,$cnum);
                if ($valid_classes ne '') {
                    $autoenrolldates = &mt('Currently enabled<br />').
                                       $valid_classes;
                }
            }
        }
    }
    return $autoenrolldates;
}

sub user_is_known {
    my $known = 0;
    if ($env{'user.name'} ne '' && $env{'user.name'} ne 'public' 
        && $env{'user.domain'} ne '' && $env{'user.domain'} ne 'public') {
        $known = 1;
    }
    return $known;
}

1;