# The LearningOnline Network with CAPA
# Navigate Maps Display Handler
#
# $Id: lonnavdisplay.pm,v 1.22.4.8 2018/09/10 23:11:26 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::lonnavdisplay;

use strict;
use Apache::Constants qw(:common :http REDIRECT);
use Apache::lonmenu();
use Apache::loncommon();
use Apache::lonnavmaps();
use Apache::lonhtmlcommon();
use Apache::lonnet;
use Apache::lonlocal;
use Apache::londocs();
use Apache::lonuserstate;

sub handler {
    my $r = shift;
    real_handler($r);
}

sub real_handler {
    my $r = shift;
    # Handle header-only request
    if ($r->header_only) {
        &Apache::loncommon::content_type($r,'text/html');
        $r->send_http_header;
        return OK;
    }

    # Check for critical messages and redirect if present.
    my ($redirect,$url) = &Apache::loncommon::critical_redirect(300);
    if ($redirect) {
        &Apache::loncommon::content_type($r,'text/html');
        $r->header_out(Location => $url);
        return REDIRECT;
    }

# ------------------------------------------------------------ Get query string
    &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'},['sort',
                                                                  'showOnlyHomework',
                                                                  'postsymb','register']);
    # Check if course needs to be re-initialized
    my $loncaparev = $r->dir_config('lonVersion');
    my ($result,@reinit) = &Apache::loncommon::needs_coursereinit($loncaparev);
    my %prog_state=();
    my $closure;

    if ($result eq 'switch') {
        &Apache::loncommon::content_type($r,'text/html');
        $r->send_http_header;
        $r->print(&Apache::loncommon::check_release_result(@reinit));
        return OK;
    } elsif ($result eq 'update') {
        my $cid = $env{'request.course.id'};
        my $cnum = $env{'course.'.$cid.'.num'};
        my $cdom = $env{'course.'.$cid.'.domain'};
        &Apache::loncommon::content_type($r,'text/html');
        $r->send_http_header;
        &startpage($r);
        my $preamble = '<div id="LC_update_'.$cid.'" class="LC_info">'.
                       '<br />'.
                       &mt('Your course session is being updated because of recent changes by course personnel.').
                       ' '.&mt('Please be patient.').'<br /></div>'.
                       '<div style="padding:0;clear:both;margin:0;border:0"></div>';
        $closure = <<ENDCLOSE;
<script type="text/javascript">
// <![CDATA[
\$("#LC_update_$cid").hide('slow');
// ]]>
</script>
ENDCLOSE
        %prog_state = &Apache::lonhtmlcommon::Create_PrgWin($r,undef,$preamble);
        &Apache::lonhtmlcommon::Update_PrgWin($r,\%prog_state,&mt('Updating course'));
        $r->rflush();
        my ($furl,$ferr) = &Apache::lonuserstate::readmap("$cdom/$cnum",\%prog_state,$r);
        &Apache::lonhtmlcommon::Update_PrgWin($r,\%prog_state,&mt('Finished'));
        if ($ferr) {
            &Apache::lonhtmlcommon::Close_PrgWin($r,\%prog_state);
            $r->print($closure.&Apache::loncommon::end_page());
            my $requrl = $r->uri;
            $env{'user.error.msg'}="$requrl:bre:0:0:Course not initialized";
            $env{'user.reinit'} = 1;
            return HTTP_NOT_ACCEPTABLE;
        }
    }

    # Create the nav map
    my $navmap = Apache::lonnavmaps::navmap->new();

    if (!defined($navmap)) {
        if ($result eq 'update') {
            &Apache::lonhtmlcommon::Close_PrgWin($r,\%prog_state);
            $r->print($closure.&Apache::loncommon::end_page());
        }
        my $requrl = $r->uri;
        $env{'user.error.msg'} = "$requrl:bre:0:0:Course not initialized";
        $env{'user.reinit'} = 1;
        return HTTP_NOT_ACCEPTABLE;
    }

    if ($result eq 'update') {
        $r->rflush();
        &Apache::lonhtmlcommon::Close_PrgWin($r,\%prog_state);
        $r->print($closure);
        $r->rflush();
    } else {
        # Send header, don't cache this page
        &Apache::loncommon::content_type($r,'text/html');
        $r->send_http_header;
        &startpage($r);
    }

    &startContentScreen($r,'navmaps');
    unless ($result eq 'update') {
        $r->rflush();
    }

    # Check that it's defined
    if (!($navmap->courseMapDefined())) {
	$r->print(&Apache::loncommon::help_open_menu('Navigation Screen','Navigation_Screen',undef,'RAT'));
        $r->print('<span class="LC_error">'.&mt('Coursemap undefined.').
		  '</span>' .
                  &Apache::loncommon::end_page());
        return OK;
    }

    my %toplinkitems=();
    my @resources = $navmap->retrieveResources();
    my $sequenceCount = 0;
    my $problemCount = 0;
    my $notaprobCount = 0;
    my $sequenceId;
    my $notools;
    foreach my $curRes (@resources) {
        if (ref($curRes)) {
            if ($curRes->is_sequence()) {
                $sequenceCount++;
                $sequenceId = $curRes->map_pc();
            } elsif ($curRes->is_problem()) {
                $problemCount ++;
            } else {
                $notaprobCount ++;
            }
        }
    }
    if (($sequenceCount == 1) && (!$problemCount) && ($notaprobCount <= 1)) {
        $notools = 1;
    }

    # If there's only one map in the top-level and we don't
    # already have a filter, automatically display it
    if ($ENV{QUERY_STRING} !~ /filter/) {
        if ($sequenceCount == 1) {
            # The automatic iterator creation in the render call 
            # will pick this up. We know the condition because
            # the defined($env{'form.filter'}) also ensures this
            # is a fresh call.
            $env{'form.filter'} = "$sequenceId";
        }
    }

    # Check to see if the student is jumping to next open, do-able problem
    if ($ENV{QUERY_STRING} =~ /^jumpToFirstHomework/) {
        # Find the next homework problem that they can do.
        my $iterator = $navmap->getIterator(undef, undef, undef, 1);
        my $curRes;
        my $foundDoableProblem = 0;
        my $minimumduedate;
        my $now = time();
	
        while ($curRes = $iterator->next()) {
            if (ref($curRes) && $curRes->is_problem()) {
                my $status = $curRes->status();
		my $thisduedate=$curRes->duedate();
                if ($thisduedate > $now 
		    && $curRes->completable()) {
                        
                    $foundDoableProblem = 1;

                    if (!defined($minimumduedate)
                        || $thisduedate<$minimumduedate) {
			# Pop open all previous maps
			my $stack = $iterator->getStack();
			pop @$stack; # last resource in the stack is the problem
			# itself, which we don't need in the map stack
			my @mapPcs = map {$_->map_pc()} @$stack;
			$env{'form.filter'} = join(',', @mapPcs);
			
			# Mark as both "here" and "jump"
			$env{'form.postsymb'} = $curRes->symb();
                        $minimumduedate=$thisduedate;
		    }
                }
            }
        }

        # If we found no problems, print a note to that effect.
        if (!$foundDoableProblem) {
            $r->print("<span class=\"LC_info\">"
                     .&mt("All homework assignments have been completed.")
                     ."</span>");
        }
    } else {
        my $link = 'navmaps?jumpToFirstHomework';
        if ($env{'form.register'}) {
            $link .= '&amp;register='.$env{'form.register'}; 
        }
        unless ($notools) {
	    &Apache::lonnavmaps::add_linkitem(\%toplinkitems,'firsthomework',
					      'location.href="'.$link.'"',
					      "Show my first due problem");
        }
    }

    my $suppressEmptySequences = 0;
    my $filterFunc = undef;
    my $resource_no_folder_link = 0;

    # Display only due homework.
    my $showOnlyHomework = 0;
    if ($env{'form.showOnlyHomework'} eq "1") {
        $showOnlyHomework = 1;
        $suppressEmptySequences = 1;
        $filterFunc = sub { my $res = shift; 
                            return $res->completable() || $res->is_map();
                        };
        my $link = 'navmaps?sort='.$env{'form.sort'};
        if ($env{'form.register'}) {
            $link .= '&amp;register='.$env{'form.register'};
        }
	&Apache::lonnavmaps::add_linkitem(\%toplinkitems,'everything',
					  'location.href="'.$link.'"',
					  'Show everything');
        $r->print("<span class=\"LC_info\">".&mt("Uncompleted Problems")."</span>");
        $env{'form.filter'} = '';
        $env{'form.condition'} = 1;
	$resource_no_folder_link = 1;
    } else {
        my $link = 'navmaps?sort='.$env{'form.sort'}.'&amp;showOnlyHomework=1';
        if ($env{'form.register'}) {
            $link .= '&amp;register='.$env{'form.register'};
        }
        unless ($notools) {
	    &Apache::lonnavmaps::add_linkitem(\%toplinkitems,'uncompleted',
					      'location.href="'.$link.'"',
					      'Show only uncompleted problems');
        }
    }

    my %selected=($env{'form.sort'} => ' selected="selected"');
    my $sort_html;
    unless ($notools) {
        $sort_html=(
              '<form name="sortForm" action="">
                 <span class="LC_nobreak">
                    <input type="hidden" name="showOnlyHomework" value="'.$env{'form.showOnlyHomework'}.'" />
                    '.&mt('Sort by:').'
                    <select name="sort" onchange="document.sortForm.submit()">
                       <option value="default"'.$selected{'default'}.'>'.&mt('Default').'</option>
                       <option value="title"'.$selected{'title'}.'>'.&mt('Title').'</option>
                       <option value="duedate"'.$selected{'duedate'}.'>'.&mt('Due Date').'</option>
                       <option value="discussion"'.$selected{'discussion'}.'>'.&mt('Has New Discussion').'</option>
                    </select>
                    <input type="hidden" name="register" value="'.$env{'form.register'}.'" />
                 </span>
               </form>');
    }
    # renderer call
    my $renderArgs = { 'cols' => [0,1,2,3],
		       'sort' => $env{'form.sort'},
                       'url' => '/adm/navmaps',
                       'navmap' => $navmap,
                       'suppressNavmap' => 1,
                       'suppressEmptySequences' => $suppressEmptySequences,
                       'filterFunc' => $filterFunc,
		       'resource_no_folder_link' => $resource_no_folder_link,
		       'sort_html'=> $sort_html,
                       'r' => $r,
                       'caller' => 'navmapsdisplay',
                       'linkitems' => \%toplinkitems,
                       'notools' => $notools};
                      
    my $render = &Apache::lonnavmaps::render($renderArgs);

    # If no resources were printed, print a reassuring message so the
    # user knows there was no error.
    if ($renderArgs->{'counter'} == 0) {
        if ($showOnlyHomework) {
            $r->print("<p><span class=\"LC_info\">".&mt("All homework is currently completed.")."</span></p>");
        } else { # both jumpToFirstHomework and normal use the same: course must be empty
            $r->print("<p><span class=\"LC_info\">".&mt("This course is empty.")."</span></p>");
        }
    }
    &endContentScreen($r);
    $r->print(&Apache::loncommon::end_page());
    $r->rflush();

    return OK;
}

sub startpage {
    my ($r) = @_;
# ----------------------------------------------------- Force menu registration
    # Header
    my $course_type = &Apache::loncommon::course_type();
    my $title = $course_type . ' Contents';
    my ($start_page,$args);
    if ($env{'form.register'}) {
        $args = {'force_register' => $env{'form.register'}};
        $start_page = &Apache::loncommon::start_page($title,undef,$args);
    } else {
        my $brcrum = [{href => '/adm/navmaps',
                       text => &mt($course_type . ' Contents'),
                       no_mt => 1},
                     ];
        $args = {'bread_crumbs' => $brcrum};
        $start_page = &Apache::loncommon::start_page($title,undef,$args);
    }
    $r->print($start_page.
              '<script type="text/javascript">'."\n".
              '// <![CDATA['."\n".
              'window.focus();'."\n".
              '// ]]>'."\n".
              '</script>');
    return;
}

sub startContentScreen {
    my ($r,$mode)=@_;

    $r->print("\n".'<ul class="LC_TabContentBigger" id="mainnav">'."\n");
    $r->print('<li'.(($mode eq 'navmaps')?' class="active"':'').'><a href="/adm/navmaps"><b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;'.&mt('Main Content').'&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</b></a></li>'."\n");
    my $allowed = &Apache::lonnet::allowed('mdc',$env{'request.course.id'});
    my ($suppcount,$errors);
    unless ($allowed) {
        my $cnum = $env{'course.'.$env{'request.course.id'}.'.num'};
        my $cdom = $env{'course.'.$env{'request.course.id'}.'.domain'};
        ($suppcount,$errors) = &Apache::lonnet::get_numsuppfiles($cnum,$cdom);
    }
    if ($allowed || $suppcount) {
        $r->print('<li '.(($mode eq 'supplemental')?' class="active"':'').'><a href="/adm/supplemental"><b>'.&mt('Supplemental Content').'</b></a></li>');
    }
    $r->print('<li'.(($mode eq 'coursesearch')?' class="active"':'').'><a href="/adm/searchcourse"><b>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;'.&mt('Content Search').'&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</b></a></li>'."\n");
    $r->print("\n".'</ul>'."\n");
    $r->print('<div class="LC_Box" style="clear:both;margin:0;"><div id="maincoursedoc" style="margin:0 0;padding:0 0;"><div class="LC_ContentBox" id="mainCourseDocuments" style="display: block;">');
}

sub endContentScreen {
   my ($r)=@_;
   $r->print('</div></div></div>');
}

1;
__END__