moodle/mod/lesson/action/moveit.php

102 lines
4.1 KiB
PHP

<?php
/****************** moveit ************************************/
if (!isteacher($course->id)) {
error("Only teachers can look at this page");
}
confirm_sesskey();
$pageid = required_param('pageid', PARAM_INT); // page to move
if (!$page = get_record("lesson_pages", "id", $pageid)) {
error("Moveit: page not found");
}
$after = required_param('after', PARAM_INT); // target page
print_heading(get_string("moving", "lesson", $page->title));
// first step. determine the new first page
// (this is done first as the current first page will be lost in the next step)
if (!$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 = get_field("lesson_pages", "id", "lessonid", $lesson->id, "nextpageid", 0)) {
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 = get_field("lesson_pages", "id", "lessonid", $lesson->id, "prevpageid", 0)) {
error("Moveit: current first page id not found");
}
}
// the rest is all unconditional...
// second step. join pages into a ring
if (!$firstpageid = get_field("lesson_pages", "id", "lessonid", $lesson->id, "prevpageid", 0)) {
error("Moveit: firstpageid not found");
}
if (!$lastpageid = get_field("lesson_pages", "id", "lessonid", $lesson->id, "nextpageid", 0)) {
error("Moveit: lastpage not found");
}
if (!set_field("lesson_pages", "prevpageid", $lastpageid, "id", $firstpageid)) {
error("Moveit: unable to update link");
}
if (!set_field("lesson_pages", "nextpageid", $firstpageid, "id", $lastpageid)) {
error("Moveit: unable to update link");
}
// third step. remove the page to be moved
if (!$prevpageid = get_field("lesson_pages", "prevpageid", "id", $pageid)) {
error("Moveit: prevpageid not found");
}
if (!$nextpageid = get_field("lesson_pages", "nextpageid", "id", $pageid)) {
error("Moveit: nextpageid not found");
}
if (!set_field("lesson_pages", "nextpageid", $nextpageid, "id", $prevpageid)) {
error("Moveit: unable to update link");
}
if (!set_field("lesson_pages", "prevpageid", $prevpageid, "id", $nextpageid)) {
error("Moveit: unable to update link");
}
// fourth step. insert page to be moved in new place...
if (!$nextpageid = get_field("lesson_pages", "nextpageid", "id", $after)) {
error("Movit: nextpageid not found");
}
if (!set_field("lesson_pages", "nextpageid", $pageid, "id", $after)) {
error("Moveit: unable to update link");
}
if (!set_field("lesson_pages", "prevpageid", $pageid, "id", $nextpageid)) {
error("Moveit: unable to update link");
}
// ...and set the links in the moved page
if (!set_field("lesson_pages", "prevpageid", $after, "id", $pageid)) {
error("Moveit: unable to update link");
}
if (!set_field("lesson_pages", "nextpageid", $nextpageid, "id", $pageid)) {
error("Moveit: unable to update link");
}
// fifth step. break the ring
if (!$newlastpageid = get_field("lesson_pages", "prevpageid", "id", $newfirstpageid)) {
error("Moveit: newlastpageid not found");
}
if (!set_field("lesson_pages", "prevpageid", 0, "id", $newfirstpageid)) {
error("Moveit: unable to update link");
}
if (!set_field("lesson_pages", "nextpageid", 0, "id", $newlastpageid)) {
error("Moveit: unable to update link");
}
redirect("view.php?id=$cm->id", get_string('movedpage', 'lesson'));
?>