/**
* This function will generate and return a list of the page images from a pdf.
* @param int|\assign $assignment
* @param int $userid
* @param int $attemptnumber (-1 means latest attempt)
* @return array(stored_file)
*/
public static function generate_page_images_for_attempt($assignment, $userid, $attemptnumber)
{
global $CFG;
require_once $CFG->libdir . '/pdflib.php';
$assignment = self::get_assignment_from_param($assignment);
if (!$assignment->can_view_submission($userid)) {
\print_error('nopermission');
}
// Need to generate the page images - first get a combined pdf.
$file = self::get_combined_pdf_for_attempt($assignment, $userid, $attemptnumber);
if (!$file) {
throw new \moodle_exception('Could not generate combined pdf.');
}
$tmpdir = \make_temp_directory('assignfeedback_editpdf/pageimages/' . self::hash($assignment, $userid, $attemptnumber));
$combined = $tmpdir . '/' . self::COMBINED_PDF_FILENAME;
$file->copy_content_to($combined);
// Copy the file.
$pdf = new pdf();
$pdf->set_image_folder($tmpdir);
$pagecount = $pdf->set_pdf($combined);
$grade = $assignment->get_user_grade($userid, true, $attemptnumber);
$record = new \stdClass();
$record->contextid = $assignment->get_context()->id;
$record->component = 'assignfeedback_editpdf';
$record->filearea = self::PAGE_IMAGE_FILEAREA;
$record->itemid = $grade->id;
$record->filepath = '/';
$fs = \get_file_storage();
// Remove the existing content of the filearea.
$fs->delete_area_files($record->contextid, $record->component, $record->filearea, $record->itemid);
$files = array();
for ($i = 0; $i < $pagecount; $i++) {
$image = $pdf->get_image($i);
$record->filename = basename($image);
$files[$i] = $fs->create_file_from_pathname($record, $tmpdir . '/' . $image);
@unlink($tmpdir . '/' . $image);
}
$pdf->Close();
// PDF loaded and never saved/outputted needs to be closed.
@unlink($combined);
@rmdir($tmpdir);
return $files;
}
