/**
  * Retrieves the lesson page type manager object
  *
  * If the object hasn't yet been created it is created here.
  *
  * @staticvar lesson_page_type_manager $pagetypemanager
  * @param lesson $lesson
  * @return lesson_page_type_manager
  */
 public static function get(lesson $lesson)
 {
     static $pagetypemanager;
     if (!$pagetypemanager instanceof lesson_page_type_manager) {
         $pagetypemanager = new lesson_page_type_manager();
         $pagetypemanager->load_lesson_types($lesson);
     }
     return $pagetypemanager;
 }

 /**
  * Returns HTML to display action links for a page
  *
  * @param lesson_page $page
  * @param bool $printmove
  * @param bool $printaddpage
  * @return string
  */
 public function page_action_links(lesson_page $page, $printmove, $printaddpage = false)
 {
     global $CFG;
     $actions = array();
     if ($printmove) {
         $printmovehtml = new moodle_url('/mod/lesson/lesson.php', array('id' => $this->page->cm->id, 'action' => 'move', 'pageid' => $page->id, 'sesskey' => sesskey()));
         $actions[] = html_writer::link($printmovehtml, '<img src="' . $this->output->pix_url('t/move') . '" class="iconsmall" alt="' . get_string('move') . '" />');
     }
     $url = new moodle_url('/mod/lesson/editpage.php', array('id' => $this->page->cm->id, 'pageid' => $page->id, 'edit' => 1));
     $actions[] = html_writer::link($url, '<img src="' . $this->output->pix_url('t/edit') . '" class="iconsmall" alt="' . get_string('update') . '" />');
     $url = new moodle_url('/mod/lesson/view.php', array('id' => $this->page->cm->id, 'pageid' => $page->id));
     $actions[] = html_writer::link($url, '<img src="' . $this->output->pix_url('t/preview') . '" class="iconsmall" alt="' . get_string('preview') . '" />');
     $url = new moodle_url('/mod/lesson/lesson.php', array('id' => $this->page->cm->id, 'action' => 'confirmdelete', 'pageid' => $page->id, 'sesskey' => sesskey()));
     $actions[] = html_writer::link($url, '<img src="' . $this->output->pix_url('t/delete') . '" class="iconsmall" alt="' . get_string('delete') . '" />');
     if ($printaddpage) {
         $options = array();
         $manager = lesson_page_type_manager::get($page->lesson);
         $links = $manager->get_add_page_type_links($page->id);
         foreach ($links as $link) {
             $options[$link['type']] = $link['name'];
         }
         $options[0] = get_string('question', 'lesson');
         $addpageurl = new moodle_url('/mod/lesson/editpage.php', array('id' => $this->page->cm->id, 'pageid' => $page->id, 'sesskey' => sesskey()));
         $addpageselect = new single_select($addpageurl, 'qtype', $options, null, array('' => get_string('addanewpage', 'lesson') . '...'), 'addpageafter' . $page->id);
         $addpageselector = $this->output->render($addpageselect);
     }
     if (isset($addpageselector)) {
         $actions[] = $addpageselector;
     }
     return implode(' ', $actions);
 }

$course = $DB->get_record('course', array('id' => $cm->course), '*', MUST_EXIST);
$lesson = new lesson($DB->get_record('lesson', array('id' => $cm->instance), '*', MUST_EXIST));
require_login($course, false, $cm);
$context = context_module::instance($cm->id);
require_capability('mod/lesson:edit', $context);
$PAGE->set_url('/mod/lesson/editpage.php', array('pageid' => $pageid, 'id' => $id, 'qtype' => $qtype));
$PAGE->set_pagelayout('admin');
if ($edit) {
    $editpage = lesson_page::load($pageid, $lesson);
    $qtype = $editpage->qtype;
    $edit = true;
} else {
    $edit = false;
}
$jumpto = lesson_page::get_jumptooptions($pageid, $lesson);
$manager = lesson_page_type_manager::get($lesson);
$editoroptions = array('noclean' => true, 'maxfiles' => EDITOR_UNLIMITED_FILES, 'maxbytes' => $CFG->maxbytes);
// If the previous page was the Question type selection form, this form
// will have a different name (e.g. _qf__lesson_add_page_form_selection
// versus _qf__lesson_add_page_form_multichoice). This causes confusion
// in moodleform::_process_submission because the array key check doesn't
// tie up with the current form name, which in turn means the "submitted"
// check ends up evaluating as false, thus it's not possible to check whether
// the Question type selection was cancelled. For this reason, a dummy form
// is created here solely to check whether the selection was cancelled.
if ($qtype) {
    $mformdummy = $manager->get_page_form(0, array('editoroptions' => $editoroptions, 'jumpto' => $jumpto, 'lesson' => $lesson, 'edit' => $edit, 'maxbytes' => $PAGE->course->maxbytes, 'returnto' => $returnto));
    if ($mformdummy->is_cancelled()) {
        redirect($returnto);
        exit;
    }

 public function __construct($arg1, $arg2)
 {
     $this->manager = lesson_page_type_manager::get($arg2['lesson']);
     parent::__construct($arg1, $arg2);
 }

/**
 * Given some question info and some data about the the answers
 * this function parses, organises and saves the question
 *
 * This is only used when IMPORTING questions and is only called
 * from format.php
 * Lifted from mod/quiz/lib.php -
 *    1. all reference to oldanswers removed
 *    2. all reference to quiz_multichoice table removed
 *    3. In SHORTANSWER questions usecase is store in the qoption field
 *    4. In NUMERIC questions store the range as two answers
 *    5. TRUEFALSE options are ignored
 *    6. For MULTICHOICE questions with more than one answer the qoption field is true
 *
 * @param opject $question Contains question data like question, type and answers.
 * @return object Returns $result->error or $result->notice.
 **/
function lesson_save_question_options($question, $lesson) {
    global $DB;

    // These lines are required to ensure that all page types have
    // been loaded for the following switch
    if (!($lesson instanceof lesson)) {
        $lesson = new lesson($lesson);
    }
    $manager = lesson_page_type_manager::get($lesson);

    $timenow = time();
    $result = new stdClass();
    switch ($question->qtype) {
        case LESSON_PAGE_SHORTANSWER:

            $answers = array();
            $maxfraction = -1;

            // Insert all the new answers
            foreach ($question->answer as $key => $dataanswer) {
                if ($dataanswer != "") {
                    $answer = new stdClass;
                    $answer->lessonid   = $question->lessonid;
                    $answer->pageid   = $question->id;
                    if ($question->fraction[$key] >=0.5) {
                        $answer->jumpto = LESSON_NEXTPAGE;
                    }
                    $answer->timecreated   = $timenow;
                    $answer->grade = $question->fraction[$key] * 100;
                    $answer->answer   = $dataanswer;
                    $answer->response = $question->feedback[$key];
                    $answer->id = $DB->insert_record("lesson_answers", $answer);
                    $answers[] = $answer->id;
                    if ($question->fraction[$key] > $maxfraction) {
                        $maxfraction = $question->fraction[$key];
                    }
                }
            }


            /// Perform sanity checks on fractional grades
            if ($maxfraction != 1) {
                $maxfraction = $maxfraction * 100;
                $result->notice = get_string("fractionsnomax", "quiz", $maxfraction);
                return $result;
            }
            break;

        case LESSON_PAGE_NUMERICAL:   // Note similarities to SHORTANSWER

            $answers = array();
            $maxfraction = -1;


            // for each answer store the pair of min and max values even if they are the same
            foreach ($question->answer as $key => $dataanswer) {
                if ($dataanswer != "") {
                    $answer = new stdClass;
                    $answer->lessonid   = $question->lessonid;
                    $answer->pageid   = $question->id;
                    $answer->jumpto = LESSON_NEXTPAGE;
                    $answer->timecreated   = $timenow;
                    $answer->grade = $question->fraction[$key] * 100;
                    $min = $question->answer[$key] - $question->tolerance[$key];
                    $max = $question->answer[$key] + $question->tolerance[$key];
                    $answer->answer   = $min.":".$max;
                    // $answer->answer   = $question->min[$key].":".$question->max[$key]; original line for min/max
                    $answer->response = $question->feedback[$key];
                    $answer->id = $DB->insert_record("lesson_answers", $answer);

                    $answers[] = $answer->id;
                    if ($question->fraction[$key] > $maxfraction) {
                        $maxfraction = $question->fraction[$key];
                    }
                }
            }

            /// Perform sanity checks on fractional grades
            if ($maxfraction != 1) {
                $maxfraction = $maxfraction * 100;
                $result->notice = get_string("fractionsnomax", "quiz", $maxfraction);
                return $result;
            }
//.........这里部分代码省略.........

/**
 * Given some question info and some data about the the answers
 * this function parses, organises and saves the question
 *
 * This is only used when IMPORTING questions and is only called
 * from format.php
 * Lifted from mod/quiz/lib.php -
 *    1. all reference to oldanswers removed
 *    2. all reference to quiz_multichoice table removed
 *    3. In shortanswer questions usecase is store in the qoption field
 *    4. In numeric questions store the range as two answers
 *    5. truefalse options are ignored
 *    6. For multichoice questions with more than one answer the qoption field is true
 *
 * @param object $question Contains question data like question, type and answers.
 * @param object $lesson
 * @param int $contextid
 * @return object Returns $result->error or $result->notice.
 **/
function lesson_save_question_options($question, $lesson, $contextid)
{
    global $DB;
    // These lines are required to ensure that all page types have
    // been loaded for the following switch
    if (!$lesson instanceof lesson) {
        $lesson = new lesson($lesson);
    }
    $manager = lesson_page_type_manager::get($lesson);
    $timenow = time();
    $result = new stdClass();
    // Default answer to avoid code duplication.
    $defaultanswer = new stdClass();
    $defaultanswer->lessonid = $question->lessonid;
    $defaultanswer->pageid = $question->id;
    $defaultanswer->timecreated = $timenow;
    $defaultanswer->answerformat = FORMAT_HTML;
    $defaultanswer->jumpto = LESSON_THISPAGE;
    $defaultanswer->grade = 0;
    $defaultanswer->score = 0;
    switch ($question->qtype) {
        case LESSON_PAGE_SHORTANSWER:
            $answers = array();
            $maxfraction = -1;
            // Insert all the new answers
            foreach ($question->answer as $key => $dataanswer) {
                if ($dataanswer != "") {
                    $answer = clone $defaultanswer;
                    if ($question->fraction[$key] >= 0.5) {
                        $answer->jumpto = LESSON_NEXTPAGE;
                        $answer->score = 1;
                    }
                    $answer->grade = round($question->fraction[$key] * 100);
                    $answer->answer = $dataanswer;
                    $answer->response = $question->feedback[$key]['text'];
                    $answer->responseformat = $question->feedback[$key]['format'];
                    $answer->id = $DB->insert_record("lesson_answers", $answer);
                    lesson_import_question_files('response', $question->feedback[$key], $answer, $contextid);
                    $answers[] = $answer->id;
                    if ($question->fraction[$key] > $maxfraction) {
                        $maxfraction = $question->fraction[$key];
                    }
                }
            }
            /// Perform sanity checks on fractional grades
            if ($maxfraction != 1) {
                $maxfraction = $maxfraction * 100;
                $result->notice = get_string("fractionsnomax", "lesson", $maxfraction);
                return $result;
            }
            break;
        case LESSON_PAGE_NUMERICAL:
            // Note similarities to shortanswer.
            $answers = array();
            $maxfraction = -1;
            // for each answer store the pair of min and max values even if they are the same
            foreach ($question->answer as $key => $dataanswer) {
                if ($dataanswer != "") {
                    $answer = clone $defaultanswer;
                    if ($question->fraction[$key] >= 0.5) {
                        $answer->jumpto = LESSON_NEXTPAGE;
                        $answer->score = 1;
                    }
                    $answer->grade = round($question->fraction[$key] * 100);
                    $min = $question->answer[$key] - $question->tolerance[$key];
                    $max = $question->answer[$key] + $question->tolerance[$key];
                    $answer->answer = $min . ":" . $max;
                    $answer->response = $question->feedback[$key]['text'];
                    $answer->responseformat = $question->feedback[$key]['format'];
                    $answer->id = $DB->insert_record("lesson_answers", $answer);
                    lesson_import_question_files('response', $question->feedback[$key], $answer, $contextid);
                    $answers[] = $answer->id;
                    if ($question->fraction[$key] > $maxfraction) {
                        $maxfraction = $question->fraction[$key];
                    }
                }
            }
            /// Perform sanity checks on fractional grades
            if ($maxfraction != 1) {
                $maxfraction = $maxfraction * 100;
                $result->notice = get_string("fractionsnomax", "lesson", $maxfraction);
//.........这里部分代码省略.........