public function validation($data, $files)
 {
     $errors = parent::validation($data, $files);
     $info = file_get_draft_area_info($data['content']);
     if ($info['filecount'] == 0) {
         $errors['content'] = get_string('required');
     }
     return $errors;
 }

 function validation($data, $files)
 {
     global $CFG;
     $errors = array();
     $draftitemid = $data['files_filemanager'];
     $fileinfo = file_get_draft_area_info($draftitemid);
     if ($fileinfo['filesize'] > $CFG->userquota) {
         $errors['files_filemanager'] = get_string('userquotalimit', 'error');
     }
     return $errors;
 }

/**
 * If successful, this function returns the name of the file
 *
 * @global object
 * @param object $post is a full post record, including course and forum
 * @param object $forum
 * @param object $cm
 * @param mixed $mform
 * @param string $message
 * @return bool
 */
function forum_add_attachment($post, $forum, $cm, $mform=null, &$message=null) {
    global $DB;

    if (empty($mform)) {
        return false;
    }

    if (empty($post->attachments)) {
        return true;   // Nothing to do
    }

    $context = get_context_instance(CONTEXT_MODULE, $cm->id);

    $info = file_get_draft_area_info($post->attachments);
    $present = ($info['filecount']>0) ? '1' : '';
    file_save_draft_area_files($post->attachments, $context->id, 'mod_forum', 'attachment', $post->id);

    $DB->set_field('forum_posts', 'attachment', $present, array('id'=>$post->id));

    return true;
}

/**
 * Returns whether a draft area has exceeded/will exceed its size limit.
 *
 * Please note that the unlimited value for $areamaxbytes is -1 {@link FILE_AREA_MAX_BYTES_UNLIMITED}, not 0.
 *
 * @param int $draftitemid the draft area item id.
 * @param int $areamaxbytes the maximum size allowed in this draft area.
 * @param int $newfilesize the size that would be added to the current area.
 * @param bool $includereferences true to include the size of the references in the area size.
 * @return bool true if the area will/has exceeded its limit.
 * @since Moodle 2.4
 */
function file_is_draft_area_limit_reached($draftitemid, $areamaxbytes, $newfilesize = 0, $includereferences = false)
{
    if ($areamaxbytes != FILE_AREA_MAX_BYTES_UNLIMITED) {
        $draftinfo = file_get_draft_area_info($draftitemid);
        $areasize = $draftinfo['filesize_without_references'];
        if ($includereferences) {
            $areasize = $draftinfo['filesize'];
        }
        if ($areasize + $newfilesize > $areamaxbytes) {
            return true;
        }
    }
    return false;
}

/**
 * Update imscp instance.
 * @param object $data
 * @param object $mform
 * @return bool true
 */
function imscp_update_instance($data, $mform)
{
    global $CFG, $DB;
    require_once "{$CFG->dirroot}/mod/imscp/locallib.php";
    $cmid = $data->coursemodule;
    $data->timemodified = time();
    $data->id = $data->instance;
    $data->structure = null;
    // Better reparse structure after each update.
    $DB->update_record('imscp', $data);
    $context = context_module::instance($cmid);
    $imscp = $DB->get_record('imscp', array('id' => $data->id), '*', MUST_EXIST);
    if (!empty($data->package) && ($draftareainfo = file_get_draft_area_info($data->package)) && $draftareainfo['filecount']) {
        $fs = get_file_storage();
        $imscp->revision++;
        $DB->update_record('imscp', $imscp);
        // Get a list of existing packages before adding new package.
        if ($imscp->keepold > -1) {
            $packages = $fs->get_area_files($context->id, 'mod_imscp', 'backup', false, "itemid ASC", false);
        } else {
            $packages = array();
        }
        file_save_draft_area_files($data->package, $context->id, 'mod_imscp', 'backup', $imscp->revision, array('subdirs' => 0, 'maxfiles' => 1));
        $files = $fs->get_area_files($context->id, 'mod_imscp', 'backup', $imscp->revision, '', false);
        $package = reset($files);
        // Purge all extracted content.
        $fs->delete_area_files($context->id, 'mod_imscp', 'content');
        // Extract package content.
        if ($package) {
            $packer = get_file_packer('application/zip');
            $package->extract_to_storage($packer, $context->id, 'mod_imscp', 'content', $imscp->revision, '/');
        }
        // Cleanup old package files, keep current + keep old.
        while ($packages and count($packages) > $imscp->keepold) {
            $package = array_shift($packages);
            $fs->delete_area_files($context->id, 'mod_imscp', 'backup', $package->get_itemid());
        }
    }
    $structure = imscp_parse_structure($imscp, $context);
    $imscp->structure = is_array($structure) ? serialize($structure) : null;
    $DB->update_record('imscp', $imscp);
    return true;
}

     $fs = get_file_storage();
     $file = $fs->get_file($user_context->id, 'user', 'draft', $draftid, $filepath, '.');
     $parent_path = $file->get_parent_directory()->get_filepath();
     if ($newfile = $zipper->archive_to_storage(array($file), $user_context->id, 'user', 'draft', $draftid, $parent_path, $filepath . '.zip', $USER->id)) {
         $return = new stdClass();
         $return->filepath = $parent_path;
         echo json_encode($return);
     } else {
         echo json_encode(false);
     }
     die;
 case 'downloaddir':
     $filepath = required_param('filepath', PARAM_PATH);
     $zipper = get_file_packer('application/zip');
     $fs = get_file_storage();
     $area = file_get_draft_area_info($draftid);
     if ($area['filecount'] == 0) {
         echo json_encode(false);
         die;
     }
     $stored_file = $fs->get_file($user_context->id, 'user', 'draft', $draftid, $filepath, '.');
     if ($filepath === '/') {
         $parent_path = '/';
         $filename = get_string('files') . '.zip';
     } else {
         $parent_path = $stored_file->get_parent_directory()->get_filepath();
         $filename = trim($filepath, '/') . '.zip';
     }
     // archive compressed file to an unused draft area
     $newdraftitemid = file_get_unused_draft_itemid();
     if ($newfile = $zipper->archive_to_storage(array($stored_file), $user_context->id, 'user', 'draft', $newdraftitemid, '/', $filename, $USER->id)) {

 public function save_question_options($formdata)
 {
     global $DB, $USER;
     $context = $formdata->context;
     $options = $DB->get_record('qtype_ddimageortext', array('questionid' => $formdata->id));
     if (!$options) {
         $options = new stdClass();
         $options->questionid = $formdata->id;
         $options->correctfeedback = '';
         $options->partiallycorrectfeedback = '';
         $options->incorrectfeedback = '';
         $options->id = $DB->insert_record('qtype_ddimageortext', $options);
     }
     $options->shuffleanswers = !empty($formdata->shuffleanswers);
     $options = $this->save_combined_feedback_helper($options, $formdata, $context, true);
     $this->save_hints($formdata, true);
     $DB->update_record('qtype_ddimageortext', $options);
     $DB->delete_records('qtype_ddimageortext_drops', array('questionid' => $formdata->id));
     foreach (array_keys($formdata->drops) as $dropno) {
         if ($formdata->drops[$dropno]['choice'] == 0) {
             continue;
         }
         $drop = new stdClass();
         $drop->questionid = $formdata->id;
         $drop->no = $dropno + 1;
         $drop->xleft = $formdata->drops[$dropno]['xleft'];
         $drop->ytop = $formdata->drops[$dropno]['ytop'];
         $drop->choice = $formdata->drops[$dropno]['choice'];
         $drop->label = $formdata->drops[$dropno]['droplabel'];
         $DB->insert_record('qtype_ddimageortext_drops', $drop);
     }
     // An array of drag no -> drag id.
     $olddragids = $DB->get_records_menu('qtype_ddimageortext_drags', array('questionid' => $formdata->id), '', 'no, id');
     foreach (array_keys($formdata->drags) as $dragno) {
         $info = file_get_draft_area_info($formdata->dragitem[$dragno]);
         if ($info['filecount'] > 0 || trim($formdata->draglabel[$dragno]) != '') {
             $draftitemid = $formdata->dragitem[$dragno];
             $drag = new stdClass();
             $drag->questionid = $formdata->id;
             $drag->no = $dragno + 1;
             $drag->draggroup = $formdata->drags[$dragno]['draggroup'];
             $drag->infinite = empty($formdata->drags[$dragno]['infinite']) ? 0 : 1;
             $drag->label = $formdata->draglabel[$dragno];
             if (isset($olddragids[$dragno + 1])) {
                 $drag->id = $olddragids[$dragno + 1];
                 unset($olddragids[$dragno + 1]);
                 $DB->update_record('qtype_ddimageortext_drags', $drag);
             } else {
                 $drag->id = $DB->insert_record('qtype_ddimageortext_drags', $drag);
             }
             if ($formdata->drags[$dragno]['dragitemtype'] == 'image') {
                 self::constrain_image_size_in_draft_area($draftitemid, QTYPE_DDIMAGEORTEXT_DRAGIMAGE_MAXWIDTH, QTYPE_DDIMAGEORTEXT_DRAGIMAGE_MAXHEIGHT);
                 file_save_draft_area_files($draftitemid, $formdata->context->id, 'qtype_ddimageortext', 'dragimage', $drag->id, array('subdirs' => 0, 'maxbytes' => 0, 'maxfiles' => 1));
             } else {
                 // Delete any existing files for draggable text item type.
                 $fs = get_file_storage();
                 $fs->delete_area_files($formdata->context->id, 'qtype_ddimageortext', 'dragimage', $drag->id);
             }
         }
     }
     if (!empty($olddragids)) {
         list($sql, $params) = $DB->get_in_or_equal(array_values($olddragids));
         $DB->delete_records_select('qtype_ddimageortext_drags', "id {$sql}", $params);
     }
     self::constrain_image_size_in_draft_area($formdata->bgimage, QTYPE_DDIMAGEORTEXT_BGIMAGE_MAXWIDTH, QTYPE_DDIMAGEORTEXT_BGIMAGE_MAXHEIGHT);
     file_save_draft_area_files($formdata->bgimage, $formdata->context->id, 'qtype_ddimageortext', 'bgimage', $formdata->id, array('subdirs' => 0, 'maxbytes' => 0, 'maxfiles' => 1));
 }

/**
 * Returns whether a draft area has exceeded/will exceed its size limit.
 *
 * Please note that the unlimited value for $areamaxbytes is -1 {@link FILE_AREA_MAX_BYTES_UNLIMITED}, not 0.
 *
 * @param int $draftitemid the draft area item id.
 * @param int $areamaxbytes the maximum size allowed in this draft area.
 * @param int $newfilesize the size that would be added to the current area.
 * @return bool true if the area will/has exceeded its limit.
 * @since 2.4
 */
function file_is_draft_area_limit_reached($draftitemid, $areamaxbytes, $newfilesize = 0)
{
    if ($areamaxbytes != FILE_AREA_MAX_BYTES_UNLIMITED) {
        $draftinfo = file_get_draft_area_info($draftitemid);
        if ($draftinfo['filesize'] + $newfilesize > $areamaxbytes) {
            return true;
        }
    }
    return false;
}

 /**
  * Save a message and destinataries
  * @param array $destinataries Destinataries for the message
  * @param array $attachments File attachments
  * @return mixed Message id or false if something fails
  */
 public function save($destinataries, $attachments, $editoritemid)
 {
     global $USER, $DB, $CFG;
     $message = new stdClass();
     $message->sender = $USER->id;
     $message->courseid = $this->courseid;
     $message->subject = $this->subject;
     $message->body = $this->body;
     //$post->message = file_save_draft_area_files($post->itemid, $context->id, 'mod_forum', 'post', $post->id, array('subdirs'=>true), $post->message);
     $message->attachment = 0;
     $message->approved = $this->approved;
     $message->timesent = $this->timesent;
     $message->timecreated = $this->timecreated;
     if ($messageid = $DB->insert_record('block_jmail', $message)) {
         foreach ($destinataries as $d) {
             if (!$d->userid) {
                 continue;
             }
             $to = new stdClass();
             $to->userid = $d->userid;
             $to->messageid = $messageid;
             $to->type = $d->type;
             $to->mread = 0;
             $to->answered = 0;
             $to->deleted = 0;
             $to->labeled = 0;
             $DB->insert_record('block_jmail_sent', $to);
         }
         $this->id = $messageid;
         $context = block_jmail_get_context(CONTEXT_COURSE, $this->courseid);
         // We need the block instance for saving the attachments
         if ($instance = $DB->get_record('block_instances', array('blockname' => 'jmail', 'parentcontextid' => $context->id))) {
             // attachments
             $context = block_jmail_get_context(CONTEXT_BLOCK, $instance->id);
             require_once $CFG->libdir . '/filelib.php';
             $message->body = file_save_draft_area_files($editoritemid, $context->id, 'block_jmail', 'body', $messageid, array('subdirs' => true), $message->body);
             $DB->set_field('block_jmail', 'body', $message->body, array('id' => $messageid));
             $info = file_get_draft_area_info($attachments);
             $present = $info['filecount'] > 0 ? '1' : '';
             file_save_draft_area_files($attachments, $context->id, 'block_jmail', 'attachment', $messageid);
             $DB->set_field('block_jmail', 'attachment', $present, array('id' => $messageid));
         }
         return $messageid;
     }
     return false;
 }

 public function validation($data, $files)
 {
     $message = $this->_customdata['message'];
     $errors = array();
     // Skip on discard
     if (!empty($data['discard'])) {
         return array();
     }
     // Course selected
     if (isset($data['course']) and $data['course'] == SITEID) {
         $errors['course'] = get_string('erroremptycourse', 'local_mail');
     }
     // Empty subject?
     if (!empty($data['send']) and !trim($data['subject'])) {
         $errors['subject'] = get_string('erroremptysubject', 'local_mail');
     }
     // At least one recipient
     if (!empty($data['send']) and (!$message or !$message->recipients())) {
         $errors['recipients'] = get_string('erroremptyrecipients', 'local_mail');
     }
     // Maximum number of attachmnents
     $options = self::file_options();
     $info = file_get_draft_area_info($data['attachments']);
     if ($info['filecount'] > $options['maxfiles']) {
         $errors['attachments'] = get_string('maxfilesreached', 'moodle', $options['maxfiles']);
     }
     return $errors;
 }

 public function validation($data, $files)
 {
     global $CFG;
     $errors = parent::validation($data, $files);
     $info = isset($data['content']) ? file_get_draft_area_info($data['content']) : array('filecount' => 0);
     $url = isset($data['externalurl']) ? trim($data['externalurl']) : '';
     if (empty($data['externalurl']) && $info['filecount'] == 0 && empty($data['objectid'])) {
         $errors['filecheck'] = get_string('required');
     } else {
         if (!empty($url)) {
             if (preg_match('|^/|', $url)) {
                 // Links relative to server root are ok - no validation necessary.
             } else {
                 if (preg_match('|^[a-z]+://|i', $url) or preg_match('|^https?:|i', $url) or preg_match('|^ftp:|i', $url)) {
                     // Normal URL.
                     if (!mediagallery_appears_valid_url($url)) {
                         $errors['externalurl'] = get_string('invalidurl', 'url');
                     }
                 } else {
                     if (preg_match('|^[a-z]+:|i', $url)) {
                         // General URI such as teamspeak, mailto, etc. - it may or may not work in all browsers.
                         // We do not validate these at all, sorry.
                     } else {
                         // Invalid URI, we try to fix it by adding 'http://' prefix.
                         // Relative links are NOT allowed because we display the link on different pages!
                         require_once $CFG->dirroot . "/mod/url/locallib.php";
                         if (!url_appears_valid_url('http://' . $url)) {
                             $errors['externalurl'] = get_string('invalidurl', 'url');
                         }
                     }
                 }
             }
         }
     }
     return $errors;
 }

/**
 * If successful, this function returns the name of the file
 *
 * @global object
 * @param object $post is a full post record, including course and forum
 * @param object $forum
 * @param object $cm
 * @param mixed $mform
 * @param string $unused
 * @param \mod_hsuforum\upload_file $uploader
 * @return bool
 */
function hsuforum_add_attachment($post, $forum, $cm, $mform = null, $unused = null, \mod_hsuforum\upload_file $uploader = null)
{
    global $DB;
    if ($uploader instanceof \mod_hsuforum\upload_file) {
        $files = $uploader->process_file_upload($post->id);
        $DB->set_field('hsuforum_posts', 'attachment', empty($files) ? 0 : 1, array('id' => $post->id));
        return true;
    }
    if (empty($mform)) {
        return false;
    }
    if (empty($post->attachments)) {
        return true;
        // Nothing to do
    }
    $context = context_module::instance($cm->id);
    $info = file_get_draft_area_info($post->attachments);
    $present = $info['filecount'] > 0 ? '1' : '';
    file_save_draft_area_files($post->attachments, $context->id, 'mod_hsuforum', 'attachment', $post->id, mod_hsuforum_post_form::attachment_options($forum));
    $DB->set_field('hsuforum_posts', 'attachment', $present, array('id' => $post->id));
    return true;
}

 public function set_attachmentsdraftid($attachmentsdraftitemid)
 {
     $fileareainfo = file_get_draft_area_info($attachmentsdraftitemid);
     if ($fileareainfo['filecount']) {
         $this->_attachmentsdraftid = $attachmentsdraftitemid;
     }
 }

 /**
  * Has the feedback file been modified?
  *
  * @param stdClass $grade Grade object.
  * @param stdClass $data Form data.
  * @return boolean True if the file area has been modified, else false.
  */
 public function is_feedback_modified(stdClass $grade, stdClass $data)
 {
     global $USER;
     $filekey = null;
     $draftareainfo = null;
     foreach ($data as $key => $value) {
         if (strpos($key, 'files_') === 0 && strpos($key, '_filemanager')) {
             $filekey = $key;
         }
     }
     if (isset($filekey)) {
         $draftareainfo = file_get_draft_area_info($data->{$filekey});
         $filecount = $this->count_files($grade->id, ASSIGNFEEDBACK_FILE_FILEAREA);
         if ($filecount != $draftareainfo['filecount']) {
             return true;
         } else {
             // We need to check that the files in the draft area are the same as in the file area.
             $usercontext = context_user::instance($USER->id);
             $fs = get_file_storage();
             $draftfiles = $fs->get_area_files($usercontext->id, 'user', 'draft', $data->{$filekey}, 'id', true);
             $files = $fs->get_area_files($this->assignment->get_context()->id, 'assignfeedback_file', ASSIGNFEEDBACK_FILE_FILEAREA, $grade->id, 'id', false);
             foreach ($files as $key => $file) {
                 // Flag for recording if we have a matching file.
                 $matchflag = false;
                 foreach ($draftfiles as $draftkey => $draftfile) {
                     if (!$file->is_directory()) {
                         // File name is the same, but it could be a different file with the same name.
                         if ($draftfile->get_filename() == $file->get_filename()) {
                             // If the file name is the same but the content hash is different, or
                             // The file path for the file has changed, then we have a modification.
                             if ($draftfile->get_contenthash() != $file->get_contenthash() || $draftfile->get_filepath() != $file->get_filepath()) {
                                 return true;
                             }
                             // These files match. Check the next file.
                             $matchflag = true;
                             // We have a match on the file name so we can move to the next file and not
                             // proceed through the other draftfiles.
                             break;
                         }
                     }
                 }
                 // If the file does not match then there has been a modification.
                 if (!$matchflag) {
                     return true;
                 }
             }
         }
     }
     return false;
 }

     $newfolderpath = $draftpath . trim($newdirname, '/') . '/';
     $fs->create_directory($user_context->id, 'user', 'draft', $itemid, $newfolderpath);
     $home_url->param('action', 'browse');
     if (!empty($newdirname)) {
         $home_url->param('draftpath', $newfolderpath);
         $str = get_string('createfoldersuccess', 'repository');
     } else {
         $home_url->param('draftpath', $draftpath);
         $str = get_string('createfolderfail', 'repository');
     }
     redirect($home_url, $str);
     break;
 case 'browse':
 default:
     $files = file_get_drafarea_files($itemid, $draftpath);
     $info = file_get_draft_area_info($itemid);
     $filecount = $info['filecount'];
     echo $OUTPUT->header();
     if ((!empty($files) or $draftpath != '/') and $env == 'filemanager') {
         echo '<div class="fm-breadcrumb">';
         $home_url->param('action', 'browse');
         $home_url->param('draftpath', '/');
         echo '<a href="' . $home_url->out() . '">' . get_string('files') . '</a> ▶';
         $trail = '';
         if ($draftpath !== '/') {
             $path = '/' . trim($draftpath, '/') . '/';
             $parts = explode('/', $path);
             foreach ($parts as $part) {
                 if ($part != '') {
                     $trail .= '/' . $part . '/';
                     $data->path[] = array('name' => $part, 'path' => $trail);

        if ($newfile = $zipper->archive_to_storage(array($filepath => $file), $user_context->id, 'user', 'draft', $draftid, $parent_path, $zipfile, $USER->id)) {
            $return = new stdClass();
            $return->filepath = $parent_path;
            echo json_encode($return);
        } else {
            echo json_encode(false);
        }
        die;

    case 'downloaddir':
        $filepath = required_param('filepath', PARAM_PATH);

        $zipper = get_file_packer('application/zip');
        $fs = get_file_storage();
        $area = file_get_draft_area_info($draftid, $filepath);
        if ($area['filecount'] == 0 && $area['foldercount'] == 0) {
            echo json_encode(false);
            die;
        }

        $stored_file = $fs->get_file($user_context->id, 'user', 'draft', $draftid, $filepath, '.');
        if ($filepath === '/') {
            $filename = get_string('files').'.zip';
        } else {
            $filename = explode('/', trim($filepath, '/'));
            $filename = array_pop($filename) . '.zip';
        }

        // archive compressed file to an unused draft area
        $newdraftitemid = file_get_unused_draft_itemid();

/**
 * If successful, this function returns the name of the file
 *
 * @global object
 * @param object $post is a full post record, including course and forum
 * @param object $forum
 * @param object $cm
 * @param mixed $mform
 * @param string $unused
 * @return bool
 */
function forum_add_attachment($post, $forum, $cm, $mform=null, $unused=null) {
    global $DB;

    if (empty($mform)) {
        return false;
    }

    if (empty($post->attachments)) {
        return true;   // Nothing to do
    }

    $context = context_module::instance($cm->id);

    $info = file_get_draft_area_info($post->attachments);
    $present = ($info['filecount']>0) ? '1' : '';
    file_save_draft_area_files($post->attachments, $context->id, 'mod_forum', 'attachment', $post->id,
            mod_forum_post_form::attachment_options($forum));

    $DB->set_field('forum_posts', 'attachment', $present, array('id'=>$post->id));

    return true;
}

 if ($bulk) {
     $draftid = file_get_submitted_draft_itemid('content');
     $files = $fs->get_area_files(context_user::instance($USER->id)->id, 'user', 'draft', $draftid, 'id DESC', false);
     $storedfile = reset($files);
     \mod_mediagallery\item::create_from_archive($gallery, $storedfile, $data);
 } else {
     $data->description = $data->description['text'];
     $data->galleryid = $gallery->id;
     if (!empty($data->id)) {
         $item = new \mod_mediagallery\item($data->id);
         $item->update($data);
     } else {
         $item = \mod_mediagallery\item::create($data);
     }
     if (!empty($data->content)) {
         $info = file_get_draft_area_info($data->content);
         file_save_draft_area_files($data->content, $context->id, 'mod_mediagallery', 'item', $item->id, $fmoptions);
         $storedfile = null;
         if ($gallery->galleryfocus != \mod_mediagallery\base::TYPE_IMAGE && $gallery->mode != 'thebox') {
             $draftid = file_get_submitted_draft_itemid('customthumbnail');
             if ($files = $fs->get_area_files(context_user::instance($USER->id)->id, 'user', 'draft', $draftid, 'id DESC', false)) {
                 $storedfile = reset($files);
             }
         }
         if ($gallery->mode != 'thebox') {
             $item->generate_image_by_type('lowres', false, $storedfile);
             $item->generate_image_by_type('thumbnail', false, $storedfile);
         }
         $params = array('context' => $context, 'objectid' => $item->id, 'other' => array('copyright_id' => $data->copyright_id, 'theme_id' => $data->theme_id));
         $event = \mod_mediagallery\event\item_updated::create($params);
         $event->add_record_snapshot('mediagallery_item', $item->get_record());