Passed
Push — master ( cb2db5...c7daa3 )
by Andreas
18:27
created

midcom_helper_nav::get_node()   A

Complexity

Conditions 1
Paths 1

Size

Total Lines 3
Code Lines 1

Duplication

Lines 0
Ratio 0 %

Code Coverage

Tests 2
CRAP Score 1

Importance

Changes 0
Metric Value
cc 1
eloc 1
nc 1
nop 1
dl 0
loc 3
ccs 2
cts 2
cp 1
crap 1
rs 10
c 0
b 0
f 0
1
<?php
2
/**
3
 * @package midcom.helper
4
 * @author The Midgard Project, http://www.midgard-project.org
5
 * @copyright The Midgard Project, http://www.midgard-project.org
6
 * @license http://www.gnu.org/licenses/lgpl.html GNU Lesser General Public License
7
 */
8
9
/**
10
 * Main Navigation interface class.
11
 *
12
 * Basically, this class proxies all requests to a midcom_helper_nav_backend
13
 * class. See the interface definition of it for further details.
14
 *
15
 * Additionally this class implements a couple of helper functions to make
16
 * common NAP tasks easier.
17
 *
18
 * <b>Important note:</b> Whenever you add new code to this class, or extend it through
19
 * inheritance, never call the proxy-functions of the backend directly, this is strictly
20
 * forbidden.
21
 *
22
 * @todo End-User documentation of node and leaf data, as the one in the backend is incomplete too.
23
 * @package midcom.helper
24
 * @see midcom_helper_nav_backend
25
 */
26
class midcom_helper_nav
27
{
28
    /**
29
     * @var midcom_helper_nav_backend
30
     */
31
    private $_backend;
32
33
    /**
34
     * @var midcom_helper_nav_backend[]
35
     */
36
    private static $_backends = [];
37
38
    /**
39
     * @var midcom_core_context
40
     */
41
    private $context;
42
43
    /**
44
     * Create a NAP instance for the currently active context
45
     */
46 437
    public function __construct()
47
    {
48 437
        $this->context = midcom_core_context::get();
49 437
        $this->_backend = $this->_get_backend();
50 437
    }
51
52
    /**
53
     * This function maintains one NAP Class per context. Usually this is enough,
54
     * since you mostly will access it in context 0, the default. The problem is, that
55
     * this is not 100% efficient: If you instantiate two different NAP Classes in
56
     * different contexts both referring to the same root node, you will get two
57
     * different instances.
58
     *
59
     * @see midcom_helper_nav
60
     */
61 437
    private function _get_backend() : midcom_helper_nav_backend
62
    {
63 437
        if (!isset(self::$_backends[$this->context->id])) {
64 282
            $root = $this->context->get_key(MIDCOM_CONTEXT_ROOTTOPIC);
65 282
            $urltopics = $this->context->get_key(MIDCOM_CONTEXT_URLTOPICS);
66 282
            self::$_backends[$this->context->id] = new midcom_helper_nav_backend($root, $urltopics);
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Bug introduced by
It seems like $urltopics can also be of type false; however, parameter $urltopics of midcom_helper_nav_backend::__construct() does only seem to accept array, maybe add an additional type check? ( Ignorable by Annotation )

If this is a false-positive, you can also ignore this issue in your code via the ignore-type  annotation

66
            self::$_backends[$this->context->id] = new midcom_helper_nav_backend($root, /** @scrutinizer ignore-type */ $urltopics);
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Bug introduced by
It seems like $root can also be of type false; however, parameter $root of midcom_helper_nav_backend::__construct() does only seem to accept midcom_db_topic, maybe add an additional type check? ( Ignorable by Annotation )

If this is a false-positive, you can also ignore this issue in your code via the ignore-type  annotation

66
            self::$_backends[$this->context->id] = new midcom_helper_nav_backend(/** @scrutinizer ignore-type */ $root, $urltopics);
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67
        }
68
69 437
        return self::$_backends[$this->context->id];
70
    }
71
72
    /* The following methods are just interfaces to midcom_helper_nav_backend */
73
74
    /**
75
     * Retrieve the ID of the currently displayed node. Defined by the topic of
76
     * the component that declared able to handle the request.
77
     *
78
     * @return int    The ID of the node in question.
79
     * @see midcom_helper_nav_backend::get_current_node()
80
     */
81 235
    public function get_current_node()
82
    {
83 235
        return $this->_backend->get_current_node();
84
    }
85
86
    /**
87
     * Retrieve the ID of the currently displayed leaf. This is a leaf that is
88
     * displayed by the handling topic. If no leaf is active, this function
89
     * returns false. (Remember to make a type sensitive check, e.g.
90
     * nav::get_current_leaf() !== false to distinguish '0' and 'false'.)
91
     *
92
     * @return int    The ID of the leaf in question or false on failure.
93
     * @see midcom_helper_nav_backend::get_current_leaf()
94
     */
95 254
    public function get_current_leaf()
96
    {
97 254
        return $this->_backend->get_current_leaf();
98
    }
99
100
    /**
101
     * Retrieve the ID of the root node. Note that this ID is dependent from the
102
     * ID of the MidCOM Root topic and therefore will change as easily as the
103
     * root topic ID might. The MIDCOM_NAV_URL entry of the root node's data will
104
     * always be empty.
105
     *
106
     * @see midcom_helper_nav_backend::get_root_node()
107
     */
108 95
    public function get_root_node() : int
109
    {
110 95
        return $this->_backend->get_root_node();
111
    }
112
113
114
    /**
115
     * Lists all Sub-nodes of $parent_node. If there are no subnodes you will get
116
     * an empty array
117
     *
118
     * @param boolean $show_noentry Show all objects on-site which have the noentry flag set.
119
     *     This defaults to false.
120
     * @see midcom_helper_nav_backend::list_nodes()
121
     */
122 12
    public function get_nodes(int $parent_node_id, bool $show_noentry = false) : array
123
    {
124 12
        return array_map([$this, 'get_node'], $this->_backend->list_nodes($parent_node_id, $show_noentry));
125
    }
126
127
    /**
128
     * Lists all leaves of $parent_node. If there are no leaves you will get an
129
     * empty array.
130
     *
131
     * @param boolean $show_noentry Show all objects on-site which have the noentry flag set.
132
     *     This defaults to false.
133
     * @see midcom_helper_nav_backend::list_leaves()
134
     */
135 17
    public function get_leaves(int $parent_node_id, bool $show_noentry = false) : array
136
    {
137 17
        return array_map([$this, 'get_leaf'], $this->_backend->list_leaves($parent_node_id, $show_noentry));
138
    }
139
140
    /**
141
     * This will give you a key-value pair describing the node with the ID
142
     * $node_id. The defined keys are described above in Node data interchange
143
     * format. You will get false if the node ID is invalid.
144
     *
145
     * @see midcom_helper_nav_backend::get_node()
146
     */
147 302
    public function get_node($node_id) : ?array
148
    {
149 302
        return $this->_backend->get_node($node_id);
150
    }
151
152
    /**
153
     * This will give you a key-value pair describing the leaf with the ID
154
     * $node_id. The defined keys are described above in leaf data interchange
155
     * format. You will get false if the leaf ID is invalid.
156
     *
157
     * @see midcom_helper_nav_backend::get_leaf()
158
     */
159 40
    public function get_leaf(string $leaf_id) : ?array
160
    {
161 40
        return $this->_backend->get_leaf($leaf_id);
162
    }
163
164
    /**
165
     * Returns the ID of the node to which $leaf_id is associated to, false
166
     * on failure.
167
     *
168
     * @param string $leaf_id    The Leaf-ID to search an uplink for.
169
     * @return int             The ID of the Node for which we have a match, or false on failure.
170
     * @see midcom_helper_nav_backend::get_leaf_uplink()
171
     */
172
    function get_leaf_uplink($leaf_id)
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173
    {
174
        return $this->_backend->get_leaf_uplink($leaf_id);
175
    }
176
177
    /**
178
     * Returns the ID of the node to which $node_id is associated to, false
179
     * on failure. The root node's uplink is -1.
180
     *
181
     * @param int $node_id    The Leaf-ID to search an uplink for.
182
     * @return int             The ID of the Node for which we have a match, -1 for the root node, or false on failure.
183
     * @see midcom_helper_nav_backend::get_node_uplink()
184
     */
185 71
    public function get_node_uplink($node_id)
186
    {
187 71
        return $this->_backend->get_node_uplink($node_id);
188
    }
189
190
    /**
191
     * Checks if the given node is within the tree of another node.
192
     *
193
     * @param int    $node_id    The node in question.
194
     * @param int    $root_id    The root node to use.
195
     */
196 76
    public function is_node_in_tree($node_id, $root_id) : bool
197
    {
198 76
        if ($node_id == $root_id) {
199 9
            return true;
200
        }
201 71
        $uplink = $this->get_node_uplink($node_id);
202
203 71
        if ($uplink == $root_id) {
204 18
            return true;
205
        }
206 53
        if (in_array($uplink, [false, -1])) {
207 53
            return false;
208
        }
209 6
        return $this->is_node_in_tree($uplink, $root_id);
210
    }
211
212
    /**
213
     * List all child elements, nodes and leaves alike, of the node with ID
214
     * $parent_node_id. For every child element, an array of ID and type (node/leaf)
215
     * is given as
216
     *
217
     * - MIDCOM_NAV_ID => 0,
218
     * - MIDCOM_NAV_TYPE => 'node'
219
     *
220
     * If there are no child elements at all the method will return an empty array,
221
     * in case of an error false.  NOTE: This method should be quite slow, there's
222
     * room for improvement... :-)
223
     */
224 9
    public function list_child_elements(int $parent_node_id) : ?array
225
    {
226 9
        if ($parent_node = $this->get_node($parent_node_id)) {
227 9
            $nav_object = midcom_helper_nav_itemlist::factory($this, $parent_node);
228 9
            return $nav_object->get_sorted_list();
229
        }
230
        return null;
231
    }
232
233
    /**
234
     * Try to resolve a guid into a NAP object.
235
     *
236
     * The code is optimized trying to avoid a full-scan if possible. To do this it
237
     * will treat topic and article guids specially: In both cases the system will
238
     * translate it using the topic id into a node id and scan only that part of the
239
     * tree non-recursively.
240
     *
241
     * A full scan of the NAP data is only done if another MidgardObject is used.
242
     *
243
     * Note: If you want to resolve a GUID you got from a Permalink, use the Permalinks
244
     * service within MidCOM, as it covers more objects than the NAP listings.
245
     *
246
     * @param boolean $node_is_sufficient if we could return a good guess of correct parent node but said node does not list the $guid in leaves return the node or try to do a full (and very expensive) NAP scan ?
247
     * @return ?array Either a node or leaf structure, distinguishable by MIDCOM_NAV_TYPE, or null on failure.
248
     * @see midcom_services_permalinks
249
     */
250 28
    public function resolve_guid(string $guid, bool $node_is_sufficient = false) : ?array
251
    {
252
        // First, check if the GUID is already known by the backend:
253 28
        if ($cached_result = $this->_backend->get_loaded_object_by_guid($guid)) {
254 1
            debug_add('The GUID was already known by the backend instance, returning the cached copy directly.');
255 1
            return $cached_result;
256
        }
257
258
        // Fetch the object in question for a start, so that we know what to do (tm)
259
        // Note, that objects that cannot be resolved will still be processed using a full-scan of
260
        // the tree. This is, for example, used by the on-delete cache invalidation.
261
        try {
262 27
            $object = midcom::get()->dbfactory->get_object_by_guid($guid);
263
        } catch (midcom_error $e) {
264
            debug_add("Could not load GUID {$guid}, trying to continue anyway. Last error was: " . $e->getMessage(), MIDCOM_LOG_WARN);
265
        }
266 27
        if (!empty($object)) {
267 27
            if ($object instanceof midcom_db_topic) {
268
                // Ok. This topic should be within the content tree,
269
                // we check this and return the node if everything is ok.
270 20
                if (!$this->is_node_in_tree($object->id, $this->get_root_node())) {
271 18
                    debug_add("The GUID {$guid} leads to an unknown topic not in our tree.", MIDCOM_LOG_WARN);
272 18
                    return null;
273
                }
274
275 2
                return $this->get_node($object->id);
276
            }
277
278 8
            if ($object instanceof midcom_db_article) {
279
                // Ok, let's try to find the article using the topic in the tree.
280
                if (!$this->is_node_in_tree($object->topic, $this->get_root_node())) {
281
                    debug_add("The GUID {$guid} leads to an unknown topic not in our tree.", MIDCOM_LOG_WARN);
282
                    return null;
283
                }
284
                if ($leaf = $this->_find_leaf_in_topic($object->topic, $guid)) {
285
                    return $leaf;
286
                }
287
288
                debug_add("The Article GUID {$guid} is somehow hidden from the NAP data in its topic, no results shown.", MIDCOM_LOG_INFO);
289
                return null;
290
            }
291
292
            // Ok, unfortunately, this is not an immediate topic. We try to traverse
293
            // upwards in the object chain to find a topic.
294 8
            if ($topic = $this->find_closest_topic($object)) {
295
                debug_add("Found topic #{$topic->id}, searching the leaves");
296
                if ($leaf = $this->_find_leaf_in_topic($topic->id, $guid)) {
297
                    return $leaf;
298
                }
299
                if ($node_is_sufficient) {
300
                    debug_add("Could not find guid in leaves (maybe not listed?), but node is sufficient, returning node");
301
                    return $this->get_node($topic->id);
302
                }
303
            }
304
        }
305
306
        // this is the rest of the lot, we need to traverse everything, unfortunately.
307
        // First, we traverse a list of nodes to be checked on by one, avoiding a recursive
308
        // function call.
309 8
        $unprocessed_node_ids = [$this->get_root_node()];
310
311 8
        while (!empty($unprocessed_node_ids)) {
312 8
            $node_id = array_shift($unprocessed_node_ids);
313
314
            // Check leaves of this node first.
315 8
            if ($leaf = $this->_find_leaf_in_topic($node_id, $guid)) {
316
                return $leaf;
317
            }
318
319
            // Ok, append all subnodes to the queue.
320 8
            $unprocessed_node_ids = array_merge($unprocessed_node_ids, $this->_backend->list_nodes($node_id, false));
321
        }
322
323 8
        debug_add("We were unable to find the GUID {$guid} in the MidCOM tree even with a full scan.", MIDCOM_LOG_INFO);
324 8
        return null;
325
    }
326
327 8
    private function _find_leaf_in_topic(int $topic, string $guid) : ?array
328
    {
329 8
        foreach ($this->get_leaves($topic, true) as $leaf) {
330
            if ($leaf[MIDCOM_NAV_GUID] == $guid) {
331
                return $leaf;
332
            }
333
        }
334 8
        return null;
335
    }
336
337 264
    public function find_closest_topic(midcom_core_dbaobject $object) : ?midcom_db_topic
338
    {
339 264
        debug_add('Looking for a topic to use via get_parent()');
340 264
        while ($parent = $object->get_parent()) {
341
            // Verify that this topic is within the current sites tree, if it is not,
342
            // we ignore it.
343 132
            if (   is_a($parent, midcom_db_topic::class)
344 132
                && $this->is_node_in_tree($parent->id, $this->get_root_node())) {
345 22
                return $parent;
346
            }
347 123
            $object = $parent;
348
        }
349 243
        return null;
350
    }
351
352
    /* The more complex interface methods starts here */
353
354
    /**
355
     * Construct a breadcrumb line.
356
     *
357
     * Gives you a line like 'Start > Topic1 > Topic2 > Article' using NAP to
358
     * traverse upwards till the root node. $separator is inserted between the
359
     * pairs, $class, if non-null, will be used as CSS-class for the A-Tags.
360
     *
361
     * The parameter skip_levels indicates how much nodes should be skipped at
362
     * the beginning of the current path. Default is to show the complete path. A
363
     * value of 1 will skip the home link, 2 will skip the home link and the first
364
     * subtopic and so on. If a leaf or node is selected, that normally would be
365
     * hidden, only its name will be shown.
366
     *
367
     * @param string    $separator        The separator to use between the elements.
368
     * @param string    $class            If not-null, it will be assigned to all A tags.
369
     * @param int       $skip_levels      The number of topic levels to skip before starting to work (use this to skip 'Home' links etc.).
370
     * @param string    $current_class    The class that should be assigned to the currently active element.
371
     */
372 10
    public function get_breadcrumb_line(string $separator = ' &gt; ', string $class = null, int $skip_levels = 0, string $current_class = null, array $skip_guids = []) : string
373
    {
374 10
        $breadcrumb_data = $this->get_breadcrumb_data();
375 10
        $result = '';
376
377
        // Detect real starting Node
378 10
        if ($skip_levels > 0) {
379 3
            if ($skip_levels >= count($breadcrumb_data)) {
380
                debug_add('We were asked to skip all breadcrumb elements that were present (or even more). Returning an empty breadcrumb line therefore.', MIDCOM_LOG_INFO);
381
                return $result;
382
            }
383 3
            $breadcrumb_data = array_slice($breadcrumb_data, $skip_levels);
384
        }
385
386 10
        $class = $class === null ? '' : ' class="' . $class . '"';
387 10
        while (current($breadcrumb_data) !== false) {
388 10
            $data = current($breadcrumb_data);
389 10
            $entry = htmlspecialchars($data[MIDCOM_NAV_NAME]);
390
391
            // Add the next element sensitive to the fact whether we are at the end or not.
392 10
            if (next($breadcrumb_data) === false) {
393 10
                if ($current_class !== null) {
394 10
                    $entry = "<span class=\"{$current_class}\">{$entry}</span>";
395
                }
396
            } else {
397 9
                if (   !empty($data['napobject'][MIDCOM_NAV_GUID])
398 9
                    && in_array($data['napobject'][MIDCOM_NAV_GUID], $skip_guids)) {
399
                    continue;
400
                }
401
402 9
                $entry = "<a href=\"{$data[MIDCOM_NAV_URL]}\"{$class}>{$entry}</a>{$separator}";
403
            }
404 10
            $result .= $entry;
405
        }
406
407 10
        return $result;
408
    }
409
410
    /**
411
     * Construct source data for a breadcrumb line.
412
     *
413
     * Gives you the data needed to construct a line like
414
     * 'Start > Topic1 > Topic2 > Article' using NAP to
415
     * traverse upwards till the root node. The components custom breadcrumb
416
     * data is inserted at the end of the computed breadcrumb line after any
417
     * set NAP leaf.
418
     *
419
     * See get_breadcrumb_line for a more end-user oriented way of life.
420
     *
421
     * <b>Return Value</b>
422
     *
423
     * The breadcrumb data will be returned as a list of associative arrays each
424
     * containing these keys:
425
     *
426
     * - MIDCOM_NAV_URL The fully qualified URL to the node.
427
     * - MIDCOM_NAV_NAME The clear-text name of the node.
428
     * - MIDCOM_NAV_TYPE One of 'node', 'leaf', 'custom' indicating what type of entry
429
     *   this is.
430
     * - MIDCOM_NAV_ID The Identifier of the structure used to build this entry, this is
431
     *   either a NAP node/leaf ID or the list key set by the component for custom data.
432
     * - 'napobject' This contains the original NAP object retrieved by the function.
433
     *   Just in case you need more information than is available directly.
434
     *
435
     * The entry of every level is indexed by its MIDCOM_NAV_ID, where custom keys preserve
436
     * their original key (as passed by the component) and prefixing it with 'custom-'. This
437
     * allows you to easily check if a given node/leave is within the current breadcrumb-line
438
     * by checking with array_key_exists.
439
     *
440
     * <b>Adding custom data</b>
441
     *
442
     * Custom elements are added to this array by using the MidCOM custom component context
443
     * at this time. You need to add a list with the same structure as above into the
444
     * custom component context key <i>midcom.helper.nav.breadcrumb</i>. (This needs
445
     * to be an array always, even if you return only one element.)
446
     *
447
     * Note, that the URL you pass in that list is always prepended with the current anchor
448
     * prefix. It is not possible to specify absolute URLs there. No leading slash is required.
449
     *
450
     * Example:
451
     *
452
     * <code>
453
     * $tmp = [
454
     *     [
455
     *         MIDCOM_NAV_URL => "list/{$this->_category}/{$this->_mode}/1/",
456
     *         MIDCOM_NAV_NAME => $this->_category_name,
457
     *     ],
458
     * ];
459
     * midcom_core_context::get()->set_custom_key('midcom.helper.nav.breadcrumb', $tmp);
460
     * </code>
461
     */
462 10
    public function get_breadcrumb_data($id = null) : array
463
    {
464 10
        $prefix = $this->context->get_key(MIDCOM_CONTEXT_ANCHORPREFIX);
465 10
        $result = [];
466
467 10
        if (!$id) {
468 10
            $curr_leaf = $this->get_current_leaf();
469 10
            $curr_node = $this->get_current_node();
470
        } else {
471
            $curr_leaf = false;
472
            $curr_node = -1;
473
474
            if ($leaf = $this->get_leaf($id)) {
475
                $curr_leaf = $leaf[MIDCOM_NAV_ID];
476
                $curr_node = $leaf[MIDCOM_NAV_NODEID];
477
            } elseif ($node = $this->get_node($id)) {
478
                $curr_node = $node[MIDCOM_NAV_ID];
479
            }
480
        }
481 10
        foreach ($this->get_node_path($curr_node) as $node_id) {
482 10
            $node = $this->get_node($node_id);
483 10
            $result[$node[MIDCOM_NAV_ID]] = [
484 10
                MIDCOM_NAV_URL => $node[MIDCOM_NAV_ABSOLUTEURL],
485
                MIDCOM_NAV_NAME => $node[MIDCOM_NAV_NAME],
486 10
                MIDCOM_NAV_TYPE => 'node',
487 10
                MIDCOM_NAV_ID => $node_id,
488 10
                'napobject' => $node,
489
            ];
490
        }
491 10
        if ($curr_leaf && $leaf = $this->get_leaf($curr_leaf)) {
492
            // Ignore Index Article Leaves
493
            if ($leaf[MIDCOM_NAV_URL] != '') {
494
                $result[$leaf[MIDCOM_NAV_ID]] = [
495
                    MIDCOM_NAV_URL => $leaf[MIDCOM_NAV_ABSOLUTEURL],
496
                    MIDCOM_NAV_NAME => $leaf[MIDCOM_NAV_NAME],
497
                    MIDCOM_NAV_TYPE => 'leaf',
498
                    MIDCOM_NAV_ID => $curr_leaf,
499
                    'napobject' => $leaf,
500
                ];
501
            }
502
        }
503
504 10
        if (midcom_core_context::get()->has_custom_key('midcom.helper.nav.breadcrumb')) {
505 7
            $customdata = midcom_core_context::get()->get_custom_key('midcom.helper.nav.breadcrumb');
506 7
            if (is_array($customdata)) {
507 7
                foreach ($customdata as $key => $entry) {
508 7
                    $id = "custom-{$key}";
509
510 7
                    $url = "{$prefix}{$entry[MIDCOM_NAV_URL]}";
511 7
                    if (   str_starts_with($entry[MIDCOM_NAV_URL], '/')
512 7
                        || preg_match('|^https?://|', $entry[MIDCOM_NAV_URL])) {
513 5
                        $url = $entry[MIDCOM_NAV_URL];
514
                    }
515
516 7
                    $result[$id] = [
517 7
                        MIDCOM_NAV_URL => $url,
518
                        MIDCOM_NAV_NAME => $entry[MIDCOM_NAV_NAME],
519 7
                        MIDCOM_NAV_TYPE => 'custom',
520 7
                        MIDCOM_NAV_ID => $id,
521 7
                        'napobject' => $entry,
522
                    ];
523
                }
524
            }
525
        }
526 10
        return $result;
527
    }
528
529
    /**
530
     * Retrieve the IDs of the nodes from the URL. First value at key 0 is
531
     * the root node ID, possible second value is the first subnode ID etc.
532
     * Contains only visible nodes (nodes which can be loaded).
533
     */
534 12
    public function get_node_path($node_id = null) : array
535
    {
536 12
        if ($node_id === null) {
537 9
            return $this->_backend->get_node_path();
538
        }
539 10
        $path = [];
540 10
        $node = $this->get_node($node_id);
541 10
        while ($node) {
542 10
            $path[] = $node[MIDCOM_NAV_ID];
543 10
            if ($node[MIDCOM_NAV_NODEID] === -1) {
544 10
                break;
545
            }
546 7
            $node = $this->get_node($node[MIDCOM_NAV_NODEID]);
547
        }
548 10
        return array_reverse($path);
549
    }
550
551
    /**
552
     * Retrieve the ID of the upper node of the currently displayed node.
553
     *
554
     * @return mixed    The ID of the node in question.
555
     */
556 1
    public function get_current_upper_node()
557
    {
558 1
        return $this->_backend->get_current_upper_node();
559
    }
560
}
561