# The LearningOnline Network with CAPA
# Source Code handler
#
# $Id: lonsource.pm,v 1.34 2015/05/23 21:02:39 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::lonsource;

use strict;
use Apache::lonnet;
use Apache::loncommon();
use Apache::lonhtmlcommon();
use Apache::lonsequence();
use Apache::Constants qw(:common :http);
use Apache::lonmeta;
use Apache::File;
use Apache::lonlocal;
use HTML::Entities;
use LONCAPA qw(:DEFAULT :match);

sub make_link {
    my ($filename, $listname) = @_;
    my $sourcelink = "/adm/source?inhibitmenu=yes&filename=".$filename."&listname=".$listname;

    return $sourcelink;
}

sub stage_2 {
    my ($r, $filename, $listname) = @_;
    my ($author)=($filename=~/\/res\/[^\/]+\/([^\/]+)\//);
    $r->print(&Apache::loncommon::start_page('Copy Problem Source Code to Authoring Space',undef,
                                             {'only_body' => 1,})
             .&mt('Please enter the directory that you would like the source code to go into.')
             .'<p>'
             .&mt('Note: the path is in reference to the root of your Authoring Space,'
                 .' and new directories will be automatically created.')
             .'</p>');
    $r->print('<form name="copy" action="/adm/source" target="_parent" method="post">
              <input type="hidden" name="filename" value="'.$filename.'" />
              <input type="hidden" name="listname" value="'.$listname.'" />
              <input type="hidden" name="action" value="copy_stage" />
              <input type="text" size="50" name="newpath" value="/'.&mt('shared_source').'/'.$author.'" />&nbsp;
              <input type="submit" value="'.&mt('Copy').'" />
              </form>'.
              &Apache::loncommon::end_page());
    return OK;
}

sub copy_author {
    my $role;
    my $domain;
    my $author_name;
    if ($env{'request.role'} =~ m{^ca\.}) {
        ($role, $domain, $author_name) = split(/\//,$env{'request.role'});
    } else {
        $role = "au.";
        $domain = $env{'user.domain'};
        $author_name = $env{'user.name'};
    }
    return ($role,$author_name,$domain);
}


sub copy_stage {
    my ($r, $filename, $listname, $newpath) = @_;

#Figure out if we are author or co-author
    my ($role,$author_name,$domain)=&copy_author();

# Construct path to copy and filter out any possibly nasty stuff
    my $path_to_new_file = $r->dir_config('lonDocRoot').
                           "/priv/$domain/$author_name/$newpath/$listname";
    $path_to_new_file=~s/\.\.//g;
    $path_to_new_file=~s/\~//g;
    $path_to_new_file=~s/\/+/\//g;

#Just checking again for access as we want to make sure that it is really ok now that we have the real path

    my ($uname,$udom)= &Apache::lonnet::constructaccess($path_to_new_file);

    if (!$uname || !$udom) {
	$r->print(&Apache::loncommon::start_page('Not Allowed',undef,{'only_body' => 1}));
	$r->print(&mt('Not allowed to create file [_1]', $path_to_new_file));
	$r->print(&Apache::loncommon::end_page());
	return;
    }

    #allowed
    $r->print(&Apache::loncommon::start_page('Copying Source',undef,{'only_body' => 1}));
    my $result = &Apache::loncfile::exists($uname, $udom, $path_to_new_file);
    $r->print($result);
    if(($result) && ($result =~ m|published|) ) {
	&delete_copy_file($r, $newpath, $filename, $path_to_new_file, '1');
    } elsif(($result) && ($result =~ m|exists!|)) {
	&confirm($r, $newpath, $filename, $path_to_new_file);
    } else {
	&copy_file($r, $newpath, $filename, $path_to_new_file);
    }
    
    $r->print(&Apache::loncommon::end_page());
    return;
}

sub confirm {
    my ($r, $newpath, $filename, $path_to_new_file) = @_;
    $r->print('<b>'.&mt('Press delete to remove file and replace it with a copy of the source you are viewing.').'</b><br /><br />');
    $r->print('<form name="delete_confirm" action="/adm/source" target="_parent" method="post">
              <input type="hidden" name="filename" value="'.$filename.'" />
              <input type="hidden" name="path" value="'.$path_to_new_file.'" />
              <input type="hidden" name="newpath" value="'.$newpath.'" />
              <input type="hidden" name="action" value="delete_confirm" />

              <input type="submit" value="Delete" />
              </form>');
    return;
}

sub delete_copy_file {
    my ($r, $newpath, $filename, $path_to_new_file, $type) = @_;
    if($type eq '1') {
        $r->print('<p><span class="LC_warning">'
                 .&mt('Cannot delete non-obsolete published file.')
                 .'</span><br />'
                 .&mt('Please use the code view in previous window to use shared code.')
                 .'<br /><br />');
        $r->print('<form name="delete_done" action="/adm/source" target="_parent" method="post">'
                 .'<input type="button" value="'.&mt('Close Window').'" name="close"'
                 .' onclick="window.close()" />'
                 .'</form></p>');
    } else {
        $r->print(&Apache::loncommon::start_page('Copying Source',undef,{'only_body' => 1}));
        if(-e $path_to_new_file) {
            unless(unlink($path_to_new_file)) {
                $r->print('<p class="LC_error"">'.&mt('Error:').' '.$!.'</p>');
                return 0;
            }
        } else {
            $r->print('<p class="LC_error">'.&mt('No such file').'</p>');
            return 0;
        }
        &copy_file($r, $newpath, $filename, $path_to_new_file);
        $r->print(&Apache::loncommon::end_page());
    }
    return;
}

sub copy_file {
    my ($r, $newpath, $filename, $path_to_new_file) = @_;
    $r->print('<b>'.&mt('Creating directories').'</b>');

#Figure out if we are author or co-author
    my ($role,$author_name,$domain)=&copy_author();

    my $path = $r->dir_config('lonDocRoot')."/priv/$domain/$author_name/";
    my @directories = split(/\//,$newpath);

    foreach my $now_checking (@directories) {
        if($now_checking ne '') {
            $path = $path.'/'.$now_checking;
            if(-e $path) {} #More moving along, isn't recursion fun'

            else {
                unless(mkdir($path, 02770)) {
                    $r->print('<p class="LC_error">'.&mt('Error:').' '.$!.'</p>');
                    return 0;
                }
                unless(chmod(02770, ($path))) {
                    $r->print('<p class="LC_error"> '.&mt('Error:').' '.$!.'</p>');
                    return 0;
                }
            }
        } else { } #Just move along

    }
    $r->print('<br /><b>'.&mt('Copying File').'</b>');
    my $problem_filename = $Apache::lonnet::perlvar{'lonDocRoot'}.$filename;
    my $file_output = &includemeta(&Apache::lonnet::getfile($problem_filename),$filename);
    my $fs=Apache::File->new(">$path_to_new_file");
    if (defined($fs)) {
        print $fs $file_output;
    }
    $r->print("<br /><br />");
    $r->print('<form name="copied_file" action="/adm/source" target="_parent" method="post">'
              .'<input type="button" value="'
              .&mt('Close Window').'" name="close" onclick="window.close()" />'
              .'</form>');
    #Some 1.3'ish feature is to include the derivative feature, will go here..'
    return;
}

sub print_item {
    my ($r,$filename,$listname) = @_;
    my $file_output = 
        &includemeta(&Apache::lonnet::getfile($Apache::lonnet::perlvar{'lonDocRoot'}.$filename),
                                              $filename);
    $r->print(&Apache::loncommon::start_page('View Source Code',undef,
                                             {'only_body' => 1}));
    if ($file_output ne '') {
        my $access_to_cstr;
        my $lonhost = $r->dir_config('lonHostID');
        if (&Apache::lonnet::is_library($lonhost)) {
            my @possdoms = &Apache::lonnet::current_machine_domains();
            foreach my $dom (@possdoms) {
                if ($env{"user.role.au./$dom/"}) {
                    $access_to_cstr = 1;
                    last;  
                }
            }
            unless ($access_to_cstr) {
                foreach my $key (keys(%env)) {
                    if ($key =~ m{^\Quser.role.ca./\E($match_domain)/}) {
                        my $adom = $1;
                        if (grep(/^\Q$adom\E$/,@possdoms)) {
                            $access_to_cstr = 1;
                            last;
                        }
                    }
                }
            }
            if ($access_to_cstr) {
                $r->print('
             <form name="copy" action="/adm/source" target="_parent" method="post">
              <input type="button" value="'.&mt('Close Window').'" name="close" onclick="window.close();" />
              <input type="hidden" name="filename" value="'.$filename.'" />
              <input type="hidden" name="listname" value="'.$listname.'" />
              <input type="hidden" name="action" value="stage2" />
              <input type="submit" value="'.&mt('Copy to Authoring Space').'" />
             </form><hr />
                ');
            } else {
                $r->print('<p><span class="LC_info">'.
                          &mt('Source code is displayed, but you can not copy to Authoring Space, as you do not have an author or co-author role on this server.').
                          '</span></p><a href="javascript:window.close();">'.&mt('Close Window').
                          '</a><br /><hr />'
                         );
            }
        } else {
            $r->print('<p><span class="LC_info">'.
                      &mt('Source code is displayed, but you can not copy to Authoring Space on this server.').
                          '</span></p><a href="javascript:window.close();">'.&mt('Close Window').
                          '</a><br /><hr />'
                     );

        }
        my $count=0;
        my $maxlength=-1;
        foreach (split ("\n", $file_output)) {
            $count+=int(length($_)/79);
            $count++;
            if (length($_) > $maxlength) {
                $maxlength = length($_);
            }
        }
        my $rows = $count;
        my $cols = $maxlength;
        $r->print('<form name="showsrc" action="" method="post" onsubmit="return false">'."\n".
                  '<textarea rows="'.$rows.'" cols="'.$cols.'" name="editxmltext">'.
                  &HTML::Entities::encode($file_output,'<>&"').'</textarea></form>');
    } else {
        $r->print('<p class="LC_warning">'.
                  &mt('Unable to retrieve file contents.').
                  '</p><a href="javascript:window.close();">'.&mt('Close Window').'</a>'
                 );
    }
    $r->print(&Apache::loncommon::end_page());
    return;
}

sub includemeta {
    my ($file_output,$orgfilename)=@_;
    my $escfilename=&escape($orgfilename);
    my $copytime=time;
    if ($file_output=~/\<meta\s*name\=\"isbasedonres\"/i) {
	$file_output=~s/(\<meta\s*name\=\"isbasedonres\"\s*content\=\"[^\"]*)\"/$1\,\Q$escfilename\E\"/i;
    } else {
	$file_output=~s/(\<(?:html|problem)[^\>]*\>)/$1\n\<meta name=\"isbasedonres\" content=\"\Q$escfilename\E\" \/\>/i;
    }
    if ($file_output=~/\<meta\s*name\=\"isbasedontime\"/i) {
	$file_output=~s/(\<meta\s*name\=\"isbasedontime\"\s*content\=\"[^\"]*)\"/$1\,\Q$copytime\E\"/i;
    } else {
	$file_output=~s/(\<(?:html|problem)[^\>]*\>)/$1\n\<meta name=\"isbasedontime\" content=\"\Q$copytime\E\" \/\>/i;
    }
    if ($file_output eq '-1') {
        return;
    } else {
        return $file_output;
    }
}

sub handler {
    my $r=shift;
    &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'},
                                            ['filename','listname']);
    my $filename = $env{'form.filename'};
    my $listname = $env{'form.listname'};
    my $source = &Apache::lonnet::metadata($filename,'sourceavail');
    if ($source ne 'open') {
        $env{'user.error.msg'}="$filename:cre:1:1:Source code not available";
        return HTTP_NOT_ACCEPTABLE;
    }
    unless (&Apache::lonnet::allowed('bre',$filename)) {
        $env{'user.error.msg'}="$filename:bre:1:1:Access to resource denied";
        return HTTP_NOT_ACCEPTABLE;
    }
    unless (&Apache::lonnet::allowed('cre','/')) {
        $env{'user.error.msg'}="$filename:cre:1:1:Access to source code denied";
        return HTTP_NOT_ACCEPTABLE;
    }

    &Apache::loncommon::content_type($r,'text/html');
    $r->send_http_header;

    if ($env{'form.action'} eq 'stage2') {
        &stage_2($r,$filename,$listname);
    } elsif($env{'form.action'} eq 'copy_stage') {
        &copy_stage($r,$filename,$listname,$env{'form.newpath'});
    } elsif($env{'form.action'} eq 'delete_confirm') {
        &delete_copy_file($r,$env{'form.newpath'},$filename, $env{'form.path'}, '0');
    } else {
        &print_item($r,$filename,$listname);
    }
    return OK;
}

1;