moodle/mod/lesson/action/moveit.php
2008-06-06 04:03:40 +00:00

102 lines
4.5 KiB
PHP

<?php // $Id$
/**
* Action for actually moving the page (database changes)
*
* @version $Id$
* @license http://www.gnu.org/copyleft/gpl.html GNU Public License
* @package lesson
**/
confirm_sesskey();
$pageid = required_param('pageid', PARAM_INT); // page to move
if (!$page = $DB->get_record("lesson_pages", array("id" => $pageid))) {
print_error("Moveit: page not found");
}
$after = required_param('after', PARAM_INT); // target page
// first step. determine the new first page
// (this is done first as the current first page will be lost in the next step)
if (!$after) {
// the moved page is the new first page
$newfirstpageid = $pageid;
// reset $after so that is points to the last page
// (when the pages are in a ring this will in effect be the first page)
if ($page->nextpageid) {
if (!$after = $DB->get_field("lesson_pages", "id", array("lessonid" => $lesson->id, "nextpageid" => 0))) {
print_error("Moveit: last page id not found");
}
} else {
// the page being moved is the last page, so the new last page will be
$after = $page->prevpageid;
}
} elseif (!$page->prevpageid) {
// the page to be moved was the first page, so the following page must be the new first page
$newfirstpageid = $page->nextpageid;
} else {
// the current first page remains the first page
if (!$newfirstpageid = $DB->get_field("lesson_pages", "id", array("lessonid" => $lesson->id, "prevpageid" => 0))) {
print_error("Moveit: current first page id not found");
}
}
// the rest is all unconditional...
// second step. join pages into a ring
if (!$firstpageid = $DB->get_field("lesson_pages", "id", array("lessonid" => $lesson->id, "prevpageid" => 0))) {
print_error("Moveit: firstpageid not found");
}
if (!$lastpageid = $DB->get_field("lesson_pages", "id", array("lessonid" => $lesson->id, "nextpageid" => 0))) {
print_error("Moveit: lastpage not found");
}
if (!$DB->set_field("lesson_pages", "prevpageid", $lastpageid, array("id" => $firstpageid))) {
print_error("Moveit: unable to update link");
}
if (!$DB->set_field("lesson_pages", "nextpageid", $firstpageid, array("id" => $lastpageid))) {
print_error("Moveit: unable to update link");
}
// third step. remove the page to be moved
if (!$prevpageid = $DB->get_field("lesson_pages", "prevpageid", array("id" => $pageid))) {
print_error("Moveit: prevpageid not found");
}
if (!$nextpageid = $DB->get_field("lesson_pages", "nextpageid", array("id" => $pageid))) {
print_error("Moveit: nextpageid not found");
}
if (!$DB->set_field("lesson_pages", "nextpageid", $nextpageid, array("id" => $prevpageid))) {
print_error("Moveit: unable to update link");
}
if (!$DB->set_field("lesson_pages", "prevpageid", $prevpageid, array("id" => $nextpageid))) {
print_error("Moveit: unable to update link");
}
// fourth step. insert page to be moved in new place...
if (!$nextpageid = $DB->get_field("lesson_pages", "nextpageid", array("id" => $after))) {
print_error("Movit: nextpageid not found");
}
if (!$DB->set_field("lesson_pages", "nextpageid", $pageid, array("id" => $after))) {
print_error("Moveit: unable to update link");
}
if (!$DB->set_field("lesson_pages", "prevpageid", $pageid, array("id" => $nextpageid))) {
print_error("Moveit: unable to update link");
}
// ...and set the links in the moved page
if (!$DB->set_field("lesson_pages", "prevpageid", $after, array("id" => $pageid))) {
print_error("Moveit: unable to update link");
}
if (!$DB->set_field("lesson_pages", "nextpageid", $nextpageid, array("id" => $pageid))) {
print_error("Moveit: unable to update link");
}
// fifth step. break the ring
if (!$newlastpageid = $DB->get_field("lesson_pages", "prevpageid", array("id" => $newfirstpageid))) {
print_error("Moveit: newlastpageid not found");
}
if (!$DB->set_field("lesson_pages", "prevpageid", 0, array("id" => $newfirstpageid))) {
print_error("Moveit: unable to update link");
}
if (!$DB->set_field("lesson_pages", "nextpageid", 0, array("id" => $newlastpageid))) {
print_error("Moveit: unable to update link");
}
lesson_set_message(get_string('movedpage', 'lesson'), 'notifysuccess');
redirect("$CFG->wwwroot/mod/lesson/edit.php?id=$cm->id");
?>