#
# 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::lonnet;
use Apache::lonlocal;
use Apache::lonsupportreq;
use Apache::lonacc;
use lib '/home/httpd/lib/perl/';
use LONCAPA;

sub handler {
    my ($r) = @_;
    &Apache::loncommon::content_type($r,'text/html');
    $r->send_http_header;
    if ($r->header_only) {
        return OK;
    }
    &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 $ccode = '';
    my %coursecodes = ();
    my %codes = ();
    my @codetitles = ();
    my %cat_titles = ();
    my %cat_order = ();
    my %idlist = ();
    my %idnums = ();
    my %idlist_titles = ();
    my $caller = 'global';
    my $format_reply;
    my $totcodes = 0;
    my $jscript = '';
    my $formname = 'coursecatalog';
    $totcodes = &Apache::lonsupportreq::retrieve_instcodes(\%coursecodes,$codedom,$totcodes);
    if ($totcodes > 0) {
        if ($ccode eq '') {
            $format_reply = &Apache::lonnet::auto_instcode_format($caller,$codedom,\%coursecodes,\%codes,\@codetitles,\%cat_titles,\%cat_order);
            if ($format_reply eq 'ok') {
                my $numtypes = @codetitles;
                &Apache::lonsupportreq::build_code_selections(\%codes,\@codetitles,\%cat_titles,\%cat_order,\%idlist,\%idnums,\%idlist_titles);
                &Apache::lonsupportreq::javascript_code_selections($formname,$numtypes,\%cat_titles,\$jscript,\%idlist,\%idnums,\%idlist_titles,\@codetitles);
            }
        }
        if ($env{'form.state'} eq 'listing') {
            $jscript .= '
function setElements() {
';
            for (my $i=0; $i<@codetitles; $i++) {
                if ($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;
        }
    }
';
                    $jscript .= '  courseSet('."'$codetitles[$i]'".');'."\n";
                } else {
                    last;
                }
            }
            $jscript .= '}';
            $jscript .= qq|
function changeSort(caller) {
    document.coursecatalog.sortby.value = caller;
    document.coursecatalog.submit();
}\n|;
        }
        my $js = '<script type"text/javascript">'."\n$jscript\n".
                 '</script>';
        my %add_entries = (topmargin    => "0",
                           marginheight => "0",
                           onLoad       =>"setElements()",);
        my $start_page =
            &Apache::loncommon::start_page('Course Catalog',$js,
                                           { 
                                             'add_entries' => \%add_entries,
                                             'no_inline_link'   => 1,});
        $r->print($start_page);

        my $numtitles = @codetitles;
        my $domdesc = $Apache::lonnet::domaindescription{$codedom};
        $r->print('<h3>'.&mt('Display information about official [_1] classes for which LON-CAPA courses have been created:',$domdesc).'</h3>');
        $r->print(&mt('<b>Choose which course(s) to list.</b><br />'));
        $r->print('<form name="coursecatalog" method="post">'); 
        if ($numtitles > 0) {
            my $lasttitle = $numtitles;
            if ($numtitles > 4) {
                $lasttitle = 4;
            }
            $r->print('<table><tr><td>'.$codetitles[0].'<br />'."\n".
                  '<select name="'.$codetitles[0].'" onChange="courseSet('."'$codetitles[0]'".')">'."\n".
                  ' <option value="-1" />Select'."\n");
            my @items = ();
            my @longitems = ();
            if ($idlist{$codetitles[0]} =~ /","/) {
                @items = split/","/,$idlist{$codetitles[0]};
            } else {
                $items[0] = $idlist{$codetitles[0]};
            }
            if (defined($idlist_titles{$codetitles[0]})) {
                if ($idlist_titles{$codetitles[0]} =~ /","/) {
                    @longitems = split/","/,$idlist_titles{$codetitles[0]};
                } else {
                    $longitems[0] = $idlist_titles{$codetitles[0]};
                }
                for (my $i=0; $i<@longitems; $i++) {
                    if ($longitems[$i] eq '') {
                        $longitems[$i] = $items[$i];
                    }
                }
            } else {
                @longitems = @items;
            }
            for (my $i=0; $i<@items; $i++) {
                $r->print(' <option value="'.$items[$i].'">'.$longitems[$i].'</option>');
            }
            $r->print('</select></td>');
            for (my $i=1; $i<$numtitles; $i++) {
                $r->print('<td>'.$codetitles[$i].'<br />'."\n".
                 '<select name="'.$codetitles[$i].'" onChange="courseSet('."'$codetitles[$i]'".')">'."\n".
                 '<option value="-1">&lt;-Pick '.$codetitles[$i-1].'</option>'."\n".
                 '</select>'."\n".
                 '</td>'
                );
            }
            $r->print('</tr></table>');
            if ($numtitles > 4) {
                $r->print('<br /><br />'.$codetitles[$numtitles].'<br />'."\n".
                    '<select name="'.$codetitles[$numtitles].
                    '" onChange="courseSet('."'$codetitles[$numtitles]'".')">'."\n".
                    '<option value="-1">&lt;-Pick '.$codetitles[$numtitles-1].
                    '</option>'."\n".'</select>'."\n");
            }
        }
        $r->print('<br /><input type="hidden" name="state" value="listing" /><input type="hidden" name="sortby" value="" /><input type="submit" name="catalogfilter" value="'.&mt('Display courses').'" /></form>');
    }
    if ($env{'form.state'} eq 'listing') {
        $r->print('<br /><br >'.&print_course_listing($codedom));
    }
    $r->print(&Apache::loncommon::end_page());
}

sub print_course_listing {
    my ($domain) = @_;
    my $output;
    my $year = $env{'form.Year'};
    my $sem = $env{'form.Semester'};
    my $dept = $env{'form.Department'};
    my $coursenum = $env{'form.Number'};
    my $instcode;
    if ($sem != -1) {
        $instcode .= $sem; 
    }
    if ($year != -1) {
        $instcode .= $year; 
    }
    if ($dept != -1) {
        $instcode .= $dept;
    }
    if ($coursenum != -1) {
        $instcode .= $coursenum; 
    }
    my %courses = &Apache::lonnet::courseiddump($domain,'.',1,$instcode,'.','.',
                                                undef,undef,'Course');
    if (keys(%courses) == 0) {
        $output = &mt('No courses match the criteria you selected.');
        return $output;
    }
    $output = &mt('<b>Note for students:</b> If you are officially enrolled in a course but there is no student role for the course in your LON-CAPA roles screen, check the default access dates and/or auto-enrollment settings for the course below.  Your roles screen displays only currently accessible roles.<br /><br />');
    $output .= &Apache::loncommon::start_data_table().
              &Apache::loncommon::start_data_table_header_row().
              '<th><a href="javascript:changeSort('."'code'".')">'.&mt('Code').'</a></th>'.
              '<th>'.&mt('Sections').'</th>'.
              '<th>'.&mt('Crosslisted').'</th>'.
              '<th><a href="javascript:changeSort('."'title'".')">'.&mt('Title').'</a></th>'.
              '<th><a href="javascript:changeSort('."'owner'".')">'.&mt('Owner').'</a></th>'.
              '<th>'.&mt('Student Status').'</th>'.
              '<th>'.&mt('Default Access Dates').'</th>'.
              '<th>'.&mt('Auto-enrollment').'</th>'.
              &Apache::loncommon::end_data_table_header_row();
    my %courseinfo;
    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,'<>&"');
        $cleandesc=~s/'/\\'/g;
        my ($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 %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});
            $output.=&Apache::loncommon::end_data_table_row();
        }
    }
    $output .= &Apache::loncommon::end_data_table();
    return $output;
}

sub courseinfo_row {
    my ($info) = @_;
    my ($cdom,$cnum,$title,$ownerlast,$code,$owner,$output);
    if (ref($info) eq 'HASH') {
        $cdom = $info->{'cdom'};
        $cnum = $info->{'cnum'};
        $title = $info->{'title'};
        $ownerlast = $info->{'ownerlastname'};
        $code = $info->{'code'};
        $owner = $info->{'owner'};
    } else {
        $output = '<td colspan="8">'.&mt('No information available for [_1].',
                                         $code).'</td>';
        return $output;
    }
    my %coursehash = &Apache::lonnet::dump('environment',$cdom,$cnum);
    my $classlist = &Apache::loncoursedata::get_classlist($cdom,$cnum);
    my %idx;
    my @classids;
    my @crosslistings;
    $idx{'status'} = &Apache::loncoursedata::CL_STATUS();
    my %status_title = &Apache::lonlocal::texthash (
                           Expired => 'Previous access',
                           Active => 'Current access',
                           Future => 'Future access',
                       );
    my %student_count = (
                           Expired => 0,
                           Active => 0,
                           Future => 0,
                       );
    while (my ($student,$data) = each %$classlist) {
        $student_count{$data->[$idx{'status'}]} ++;
    }
    my $seclist = &identify_sections($coursehash{'internal.sectionnums'});
    my $xlist_items = &identify_sections($coursehash{'internal.crosslistings'});
    my $countslist;
    my $startaccess = '';
    my $endaccess = '';
    my $now;
    my ($accessdates,$autoenrolldates,$showsyllabus);
    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) {
        $accessdates .= &mt('From: ').$startaccess.'<br />';
    }
    if ($endaccess) {
        $accessdates .= &mt('To: ').$endaccess.'<br />';
    }
    $autoenrolldates = &mt('Not enabled');
    if (defined($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 />').
                                       $valid_classes;
                }
            }
        }
    }
    if (defined($coursehash{'showsyllabus'})) {
        $showsyllabus = $coursehash{'showsyllabus'};
    } 
    foreach my $status ('Active','Future','Expired') {
        $countslist .= '<nobr>'.$status_title{$status}.': '.
                       $student_count{$status}.'</nobr><br />';
    }
    if ($xlist_items eq '') {
        $xlist_items = &mt('No');
    }
    $output = '<td>'.$coursehash{'internal.coursecode'}.'</td>'.
              '<td>'.$seclist.'</td>'.
              '<td>'.$xlist_items.'</td>'.
              '<td>'.$title.'&nbsp;<font size="-2">';
    if ($showsyllabus) {
        $output .= &Apache::loncommon::syllabuswrapper(&mt('Syllabus'),$cnum,$cdom);
    }
    $output .= '</font></td>'.
               '<td>'.$ownerlast.'</td>'.
               '<td>'.$countslist.'</td>'.
               '<td>'.$accessdates.'</td>'.
               '<td>'.$autoenrolldates.'</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 = $1;
            if (!grep/^$sec$/,@secnums) {
                push (@secnums,$sec);
            }
        }
    }
    @secnums = sort {$a <=> $b} @secnums;
    my $seclist = join(', ',@secnums);
    return $seclist;
}

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::autovalidate_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::autovalidate_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;
}


1;