# The LearningOnline Network with CAPA
# Extract domain, courseID, and symb from a shortened URL,
# and switch role to a role in designated course.
#
# $Id: lontiny.pm,v 1.4 2018/07/01 00:03:44 raeburn Exp $
#
# 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::lontiny;

use strict;
use Apache::Constants qw(:common :http);
use Apache::lonnet;
use Apache::loncommon;
use Apache::lonhtmlcommon;
use Apache::lonroles;
use Apache::lonlocal;
use LONCAPA qw(:DEFAULT :match);

sub handler {
    my $r = shift;
    my %user;
    my $handle = &Apache::lonnet::check_for_valid_session($r,undef,\%user);
    if ($handle ne '') { 
        if ($r->uri =~ m{^/tiny/($match_domain)/(\w+)$}) {
            my ($cdom,$key) = ($1,$2);
            if (&Apache::lonnet::domain($cdom) ne '') {
                my $configuname = &Apache::lonnet::get_domainconfiguser($cdom);
                my $tinyurl;
                my ($result,$cached)=&Apache::lonnet::is_cached_new('tiny',$cdom."\0".$key);
                if (defined($cached)) {
                    $tinyurl = $result;
                } else {
                    my %currtiny = &Apache::lonnet::get('tiny',[$key],$cdom,$configuname);
                    if ($currtiny{$key} ne '') {
                        $tinyurl = $currtiny{$key};
                        &Apache::lonnet::do_cache_new('tiny',$cdom."\0".$key,$currtiny{$key},600);
                    }
                }
                if ($tinyurl) {
                    my ($cnum,$symb) = split(/\&/,$tinyurl);
                    if ($cnum =~ /^$match_courseid$/) {
                        my $chome = &Apache::lonnet::homeserver($cnum,$cdom);
                        if ($chome ne 'no_host') {
                            my %crsenv = &Apache::lonnet::coursedescription("$cdom/$cnum");
                            my @possroles = ('in','ta','ep','st','cr','ad');
                            if ($crsenv{'type'} eq 'Community') {
                                unshift(@possroles,'co');
                            } else {
                                unshift(@possroles,'cc');
                            }
                            my %roleshash = &Apache::lonnet::get_my_roles($env{'user.uname'},
                                                                          $env{'user.domain'},
                                                                          'userroles',undef,
                                                                          \@possroles,[$cdom],1);
                            my (%possroles,$hassection);
                            if (keys(%roleshash)) {
                                foreach my $entry (keys(%roleshash)) {
                                    if ($entry =~ /^\Q$cnum:$cdom:\E([^:]+):([^:]*)$/) {
                                        $possroles{$1} = $2;
                                        if ($2 ne '') {
                                            $hassection = 1;
                                        }
                                    }
                                }
                            }
                            my @allposs = keys(%possroles);
                            if ($env{'request.lti.login'}) {
                                &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'});
                                if ($env{'request.lti.target'} eq '') {
                                    if ($env{'form.ltitarget'} eq 'iframe') {
                                        &Apache::lonnet::appenv({'request.lti.target' => 'iframe'});
                                        delete($env{'form.ltitarget'});
                                    }
                                }
                                if ($env{'form.selectrole'}) {
                                    foreach my $role (@allposs) {
                                        my $newrole = "$role./$cdom/$cnum";
                                        if ($possroles{$allposs[0]} ne '') {
                                            $newrole .= "/$possroles{$role}";
                                        }
                                        if ($env{"form.$newrole"}) {
                                            my $destination .= '/adm/roles?selectrole=1&'.$newrole.'=1'.
                                                               '&destinationurl='.&HTML::Entities::encode($r->uri);
                                            if ($env{'form.ltitarget'} eq 'iframe') {
                                                $destination .= '&ltitarget=iframe';
                                            }
                                            &do_redirect($r,$destination);
                                            return OK;
                                        }
                                    }
                                }
                            }
                            if (@allposs == 0) {
                                &show_roles($r,\%crsenv,\%possroles);
                            } elsif (@allposs == 1) {
                                my $newrole = "$allposs[0]./$cdom/$cnum";
                                $newrole = "$allposs[0]./$cdom/$cnum";
                                if ($possroles{$allposs[0]} ne '') {
                                    $newrole .= "/$possroles{$allposs[0]}"; 
                                }
                                my $destination .= '/adm/roles?selectrole=1&'.$newrole.'=1'.
                                                   '&destinationurl='.&HTML::Entities::encode($r->uri);
                                &do_redirect($r,$destination);
                            } elsif (keys(%possroles) > 1) {
                                if (grep(/^(cc|co)$/,@allposs)) {
                                    my $newrole;
                                    if (exists($possroles{'cc'})) {
                                        $newrole = 'cc';
                                    } else {
                                        $newrole = 'co';
                                    }
                                    $newrole .= "./$cdom/$cnum";
                                    my $destination .= '/adm/roles?selectrole=1&'.$newrole.'=1'.
                                                       '&destinationurl='.&HTML::Entities::encode($r->uri);
                                    &do_redirect($r,$destination);
                                } else {
                                    my $hascustom;
                                    if (grep(/^cr\//,@allposs)) {
                                        $hascustom = 1;
                                    }
                                    &show_roles($r,\%crsenv,\%possroles,$hassection,$hascustom);
                                }
                            }
                            return OK;
                        }
                    }
                }
            }
        }
        &generic_error($r);
        return OK;
    } else {
        return FORBIDDEN;
    }
}

sub do_redirect {
    my ($r,$destination) = @_;
    my $windowname = 'loncapaclient';
    if ($env{'request.lti.login'}) {
        $windowname .= 'lti';
    }
    my $header = '<meta HTTP-EQUIV="Refresh" CONTENT="0; url='.$destination.'" />';
    my $args = {'bread_crumbs' => [{'href' => '','text' => 'Role initialization'},],};
    &Apache::loncommon::content_type($r,'text/html');
    $r->send_http_header;
    $r->print(&Apache::loncommon::start_page('Valid link',$header,$args).
              &Apache::lonhtmlcommon::scripttag('self.name="'.$windowname.'";').
              '<h1>'.&mt('Welcome').'</h1>'.
              '<p>'.&mt('Welcome to the Learning[_1]Online[_2] Network with CAPA. Please wait while your session is being set up.','<i>','</i>').'</p><p>'.
              '<a href="'.$destination.'">'.&mt('Continue').'</a></p>'.
              &Apache::loncommon::end_page());
    return;
}

sub show_roles {
    my ($r,$crsenv,$possroles,$hassection,$hascustom) = @_;
    &Apache::loncommon::content_type($r,'text/html');
    $r->send_http_header;
    my ($crsdesc,$crstype,$cdom,$cnum,$header,$title,$preamble,$datatable,$js,$args);
    if (ref($crsenv) eq 'HASH') {
        $crsdesc = $crsenv->{'description'};
        $crstype = $crsenv->{'type'};
        $cdom = $crsenv->{'domain'};
        $cnum = $crsenv->{'num'};
    }
    if ($crstype eq '') {
        $crstype = 'Course';
    }
    my $lc_crstype = lc($crstype);
    if ($crsdesc ne '') {
        $header = &mt("The page you requested belongs to the following $lc_crstype: [_1]",
                      '<i>'.$crsdesc.'</i>');
    }
    if (ref($possroles) eq 'HASH') {
        if (keys(%{$possroles}) > 0) {
            $args = {'bread_crumbs' => [{'href' => '','text' => "Choose role in $lc_crstype"},],};
            $title = 'Choose a role'; #Do not localize.
            if ($crstype eq 'Community') {
                $preamble = &mt('You have the following active roles in this community:');
            } else { 
                $preamble = &mt('You have the following active roles in this course:');
            }
            $datatable = '<form name="" action="/adm/roles">'.
                         '<input type="hidden" name="newrole" value="" />'.
                         '<input type="hidden" name="selectrole" value="1" />'.
                         '<input type="hidden" name="destinationurl" value="'.$r->uri.'" />'.
                         &Apache::loncommon::start_data_table().
                         &Apache::loncommon::start_data_table_header_row().
                         '<th></th><th>'.&mt('User role').'</th>';
            if ($hassection) {
                $datatable .= '<th>'.&mt('Section').'</th>';
            }
            if ($hascustom) {
                $datatable .= '<th>'.&mt('Information').'</th>';
            }
            $datatable .= &Apache::loncommon::end_data_table_header_row();
            my @available = sort(keys(%{$possroles}));
            foreach my $role ('ad','in','ta','ep','st','cr') {
                foreach my $key (@available) {
                    if ($key =~ m{^$role($|/)}) {
                        my $trolecode = "$key./$cdom/$cnum";
                        my $rolename = &Apache::lonnet::plaintext($key,$crstype,$cdom.'_'.$cnum);
                        my $sec = $possroles->{$key};
                        if ($sec ne '') {
                            $trolecode .= '/'.$sec;
                        }
                        my $buttonname=$trolecode;
                        $buttonname=~s/\W//g;
                        $datatable .= &Apache::loncommon::start_data_table_row().
                                      '<td><input name="'.$buttonname.'" type="button" value="'.
                                      &mt('Select').'" onclick="javascript:enterrole(this.form,'.
                                      "'$trolecode','$buttonname'".');" /></td>';
                        if ($key =~ /^cr\//) {
                            my ($rdummy,$rdomain,$rauthor,$rrole)=split(/\//,$key);
                            $datatable .= '<td><span class="LC_nobreak">'.$rolename.'</span></td>';
                            if ($hassection) {
                                $datatable .= '<td>'.$sec.'</td>';
                            }
                            $datatable.= '<td><span class="LC_fontsize_small LC_cusr_emph">'.
                                          &mt('Custom role defined by [_1]',$rauthor.':'.$rdomain).
                                          '</td>';
                        } else {
                            if ($hassection) {
                                $datatable .= '<td>'.$rolename.'</td>';
                                if ($hascustom) {
                                    $datatable .= '<td colspan="2">'.$sec.'</td>';
                                } else {
                                    $datatable .= '<td>'.$sec.'</td>';
                                }
                            } elsif ($hascustom) {
                                $datatable .= '<td colspan="2">'.$rolename.'</td>';
                            } else {
                                $datatable .= '<td>'.$rolename.'</td>';
                            }
                        }
                        $datatable .= &Apache::loncommon::end_data_table_row();
                    }
                }
            }
            $datatable .= &Apache::loncommon::end_data_table().
                          '</form>';
            my $standby = &mt('Role selected. Please stand by.');
            $js = <<"ENDJS";
<script type="text/javascript">
// <![CDATA[

active=true;

function enterrole (thisform,rolecode,buttonname) {
    if (active) {
        active=false;
        document.title='$standby';
        window.status='$standby';
        thisform.newrole.value=rolecode;
        thisform.submit();
    } else {
       alert('$standby');
    }
}

// ]]>
</script>
ENDJS
        } else {
            $title = 'No active role';
            $preamble = &mt("You have no active roles in this $lc_crstype so the page is currently unavailable to you.");
            $args = {'bread_crumbs' => [{'href' => '','text' => 'Role status'},],};
        }
    }
    &Apache::loncommon::content_type($r,'text/html');
    $r->send_http_header;
    $r->print(&Apache::loncommon::start_page($title,$js,$args).
              '<h3>'.$header.'</h3>'.
              '<div>'.$preamble.'</div>'.
              $datatable.
              &Apache::loncommon::end_page());
    return;
}

sub generic_error {
    my ($r) = @_;
    my $continuelink;
    unless ($env{'request.lti.login'}) {
        my $linktext;
        if ($env{'user.adv'}) {
            $linktext = &mt('Continue to your roles page');
        } else {
            $linktext = &mt('Continue to your courses page');
        }
        $continuelink='<a href="/adm/roles">'.$linktext.'</a>';
    }
    my $msg = &mt('The page you requested does not exist.');
    &Apache::loncommon::content_type($r,'text/html');
    $r->send_http_header;
    my $args = {'bread_crumbs' => [{'href' => '','text' => 'Link status'},],};
    $r->print(&Apache::loncommon::start_page('Invalid URL',undef,$args).
              '<div class="LC_error">'.$msg.'</div>'.
              '<p>'.$continuelink.'</p>'.
              &Apache::loncommon::end_page());
    return;
}

1;