woocommerce-pos / includes / API / V2 / Variations_Controller.php

Variations_Controller.php in WCPOS – Point of Sale (POS) plugin for WooCommerce 1.10.4, at includes/API/V2/Variations_Controller.php

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1	<?php
2	/**
3	* WCPOS sync read surface.
4	*
5	* @package WCPOS\WooCommercePOS\API\V2
6	*/
7
8	namespace WCPOS\WooCommercePOS\API\V2;
9
10	use WC_Product_Variation;
11	use WC_REST_Product_Variations_Controller;
12	use WCPOS\WooCommercePOS\Services\Barcode_Field;
13	use WCPOS\WooCommercePOS\Sync\Api;
14	use WCPOS\WooCommercePOS\Sync\Collection_Rules;
15	use WCPOS\WooCommercePOS\Sync\Collection_Rules_Plan;
16	use WCPOS\WooCommercePOS\Sync\Digest_Index;
17	use WCPOS\WooCommercePOS\Sync\Endpoint_Permissions;
18	use WCPOS\WooCommercePOS\Sync\Pos_Visibility;
19	use WCPOS\WooCommercePOS\Sync\Product_Serializer;
20	use WP_Error;
21	use WP_Query;
22	use WP_REST_Request;
23	use WP_REST_Response;
24	use WP_REST_Server;
25
26	// phpcs:disable Squiz.Commenting, Generic.Commenting -- Ported lab documentation is preserved verbatim.
27
28	/**
29	* Variations document endpoint — the collection's hydration AND list/seed lane (ADR 0034).
30	*
31	* Why a flat route: the change-signal yields BARE variation ids (no parent), and WooCommerce's
32	* only variation routes are parent-mediated (`products/<parent>/variations`). One flat route
33	* IS the cross-parent collection: bare pages seed the complete replica (the idle trickle),
34	* `include=` is one filter on it (targeted hydration, no parent->child dance), and the
35	* SKU/barcode discovery search is another.
36	*
37	* Why it EXTENDS WooCommerce's variations controller: because that is all the route ever needed.
38	* WooCommerce's `get_objects()` already answers a cross-parent query — with no `product_id` in
39	* the route there is no parent constraint, and `include`/`search`/`orderby`/pagination are its
40	* own collection params. 1.9.x did exactly this: `parent::get_items( $request )`, one line
41	* (`API\V1\Product_Variations_Controller::wcpos_get_all_items`).
42	*
43	* The previous version of this class extended a bare `WP_REST_Controller` and rebuilt the query
44	* by hand — ~90 lines of raw postmeta SQL, five hand-declared args, no item schema — on the
45	* stated grounds that "wc/v3 has no cross-parent variations?include=". That claim was false, and
46	* the cost of acting on it was the payload: a variation hydrated through the PRODUCTS controller
47	* carries `images[]` instead of `image`, which blanked every variation thumbnail in the POS on
48	* 1.10.0 and wrote the parent's image onto every order line (#1710).
49	*
50	* What stays ours, and only this: the sync document envelope the engine reads
51	* (`documents[].{id,parent_id,payload,_rxdb_digest}`), POS visibility, the barcode carrier
52	* search, and the request bounds. Everything else is WooCommerce's.
53	*/
54	class Variations_Controller extends WC_REST_Product_Variations_Controller {
55	/**
56	* Request keys the variation Collection Rules plan reads on this lane.
57	*
58	* @var array
59	*/
60	private const WCPOS_SORT_PARAM_MAP = array(
61	'orderby' => 'orderby',
62	'order' => 'order',
63	);
64
65	/**
66	* The request whose declared sort `wcpos_posts_clauses()` applies.
67	*
68	* @var null\|WP_REST_Request
69	*/
70	private $wcpos_sort_request = null;
71
72	use Endpoint_Permissions;
73
74	private const MAX_SKU_LENGTH = 4096;
75	private const MAX_SKU_TERMS = 100;
76	private const MAX_SEARCH_LENGTH = 256;
77	private const MAX_SEARCH_TERMS = 10;
78	private const MAX_PAGE = 1000;
79
80
81	public function register_routes(): void {
82	/*
83	* ONLY the flat sync route. `parent::register_routes()` is deliberately not called: the
84	* v2 namespace is a read/sync surface, and writes ride Write_Controller, which already
85	* pushes through WooCommerce's nested routes. Registering WC's CRUD routes here would
86	* widen the POS-marker-gated surface for no consumer.
87	*
88	* The args and the schema are WooCommerce's own, so `include`, `search`, `orderby`,
89	* `order`, `offset`, `page`, `per_page`, `status` … all behave exactly as they do on
90	* wc/v3, and the route documents itself in the REST index.
91	*/
92	register_rest_route(
93	Api::ROUTE_NAMESPACE,
94	'/variations',
95	array(
96	array(
97	'methods' => WP_REST_Server::READABLE,
98	'callback' => array( $this, 'get_variations' ),
99	'permission_callback' => array( $this, 'permissions_check' ),
100	'args' => $this->get_collection_params(),
101	),
102	'schema' => array( $this, 'get_public_item_schema' ),
103	)
104	);
105	}
106
107	/**
108	* Narrow WooCommerce's variation query to what the POS may serve.
109	*
110	* Everything WooCommerce already understands — `include`, `offset`, `order`, pagination,
111	* status — comes from `parent::prepare_objects_query()`, which also applies
112	* `woocommerce_rest_product_variation_object_query` internally (wc/v3's CRUD controller fires
113	* it there, not in `get_items()`), so third-party query scoping reaches every lane built
114	* through this method. Layered on top — deliberately AFTER that filter, so a third party
115	* cannot widen what the POS may serve: POS visibility, the
116	* barcode-carrier search, and the sort keys the POS grids offer. This is the seam 1.9.x used
117	* for the same job (`API\V1\Product_Variations_Controller::prepare_objects_query`).
118	*
119	* @param WP_REST_Request $request Full details about the request.
120	*
121	* @return array
122	*/
123	protected function prepare_objects_query( $request ) {
124	/*
125	* WooCommerce splits `sku` on commas without trimming, so `sku=A, B` looks for " B".
126	* Normalize before it sees the param rather than reimplementing its matching.
127	*/
128	$sku = (string) ( $request->get_param( 'sku' ) ?? '' );
129	if ( '' !== $sku ) {
130	$terms = array_values(
131	array_filter(
132	array_map( 'trim', explode( ',', $sku ) ),
133	static function ( string $term ): bool {
134	return '' !== $term;
135	}
136	)
137	);
138	$sku = implode( ',', $terms );
139	$request->set_param( 'sku', $sku );
140	}
141
142	$args = parent::prepare_objects_query( $request );
143
144	/*
145	* A product is not a variation document.
146	*
147	* WooCommerce widens `post_type` to `array( 'product', 'product_variation' )` whenever
148	* `sku` is set, because the two share one SKU space. On THIS route that would serve a
149	* simple product as a variation — and the client would file it into its variations
150	* collection, the mirror image of the misfiled-variation pollution it already carries a
151	* one-shot repair for. Type purity on a variations route is ours to enforce.
152	*/
153	$args['post_type'] = $this->post_type;
154
155	/*
156	* `search` means the barcode CARRIERS here, not the post title.
157	*
158	* WooCommerce maps `search` onto `s`, which searches post_title/content — useless for a
159	* variation, whose title is a generated attribute string. The POS searches what a cashier
160	* actually types or scans: the SKU and whichever meta key the store configured as its
161	* barcode field (`Barcode_Field::search_keys()`). Any term matching any carrier wins,
162	* which is the semantics the previous hand-rolled SQL had and the specs pin.
163	*
164	* `sku` is left to WooCommerce: its own exact/comma-list handling is what the
165	* sku-beats-search precedence rule relies on.
166	*/
167	$search = (string) ( $request->get_param( 'search' ) ?? '' );
168	if ( '' !== $sku ) {
169	// SKU is an exact lookup and outranks a fuzzy one; leaving WooCommerce's post-title
170	// `s` in place would AND the two and return nothing.
171	unset( $args['s'] );
172	}
173	if ( '' !== $search && '' === $sku ) {
174	unset( $args['s'] );
175	$args['wcpos_variation_search'] = true;
176	$carriers = array( 'relation' => 'OR' );
177	foreach ( (array) preg_split( '/\s+/', trim( $search ), -1, PREG_SPLIT_NO_EMPTY ) as $term ) {
178	foreach ( Barcode_Field::search_keys() as $key ) {
179	$carriers[] = array(
180	'key' => $key,
181	'value' => $term,
182	'compare' => 'LIKE',
183	);
184	}
185	}
186	if ( 1 < \count( $carriers ) ) {
187	$args['meta_query'] = $this->add_meta_query( $args, $carriers ); // phpcs:ignore WordPress.DB.SlowDBQuery.slow_db_query_meta_query
188	}
189	}
190
191	/*
192	* This route only ever offers what the store owner has for sale — on EVERY lane, including
193	* `include`.
194	*
195	* WooCommerce's Enabled checkbox on the variation metabox writes `post_status = private`
196	* when unchecked ({@see \WC_Meta_Box_Product_Data::save_variations()}), and WooCommerce
197	* honours that everywhere a customer can reach: `get_visible_children()` and
198	* `get_available_variations()` both drop it. A cashier must not be able to sell a variation
199	* the owner switched off, so the POS behaves the same way.
200	*
201	* The `include` lane is NOT exempt. Being asked for an id by name is not evidence the owner
202	* wants it sold: the client learns those ids from the parent's `variations[]`, which
203	* WooCommerce fills from `get_children()` — publish AND private — and from the change
204	* signal, which journals a disabled variation like any other post. A disabled id simply is
205	* not hydrated, the client's targeted-pull shortfall prunes it, and it leaves every till.
206	* Re-enabling saves the variation, which journals it, and it comes back.
207	*
208	* Set after `parent::prepare_objects_query()` so an explicit `status` param cannot widen it.
209	*/
210	$args['post_status'] = 'publish';
211
212	/*
213	* Leg-3 (ADR 0014 WP-M5): POS-hidden (`online_only`) variations are never served. As a
214	* query exclusion rather than a post-hoc filter of the result, so paging and totals count
215	* the same set the client is allowed to see.
216	*
217	* Through the helper, NOT a raw `post__not_in` merge: `parent::prepare_objects_query()`
218	* maps `include` to `post__in`, and WP_Query IGNORES `post__not_in` when `post__in` is
219	* present — so `?search=X&include=<hidden id>` would have served a hidden variation.
220	* `apply_to_wp_query_args()` already owns that trap: it intersects `post__in` with the
221	* hidden set and pins an empty intersection to `array( 0 )`.
222	*/
223	$args = ( new Pos_Visibility() )->apply_to_wp_query_args( $args, Pos_Visibility::VARIATIONS );
224
225	/*
226	* The POS sorts on fields WooCommerce does not offer as orderby values. They are
227	* declared in Sync\Collection_Rules and projected into get_collection_params()
228	* below — without that, `orderby=sku` is rejected by REST argument validation
229	* before anything here runs.
230	*
231	* They are applied as SQL clauses, NOT as `meta_key` + `orderby => meta_value`:
232	* that pair INNER JOINs postmeta and drops every variation with no value for the
233	* key, so the sort silently filtered. `wcpos_posts_clauses()` LEFT JOINs instead
234	* and orders the meta-less rows last.
235	*/
236	$this->wcpos_sort_request = $request;
237	add_filter( 'posts_clauses', array( $this, 'wcpos_posts_clauses' ), 10, 2 );
238
239	return $args;
240	}
241
242	/**
243	* GET /variations — the flat collection's three lanes, one response shape.
244	*
245	* `?sku=`/`?search=` discovers by barcode carrier; a bare request serves one
246	* collection page (the trickle's seed lane); `?include=12,34` hydrates the
247	* named ids. All three resolve ids through WooCommerce's collection query,
248	* then hydrate through the shared assembly line below. Mirrors the wc/v3
249	* `products?include=` shape; the parent is resolved server-side off the
250	* loaded variation object (get_parent_id), so the client never needs to know
251	* parents. Unknown / non-variation ids are skipped (deletes are handled by
252	* the change-signal tombstone path, not here).
253	*/
254	public function get_variations( WP_REST_Request $request ) {
255	$started = microtime( true );
256	$search_meta = null;
257	if ( $request->has_param( 'sku' ) \|\| $request->has_param( 'search' ) ) {
258	$validation = $this->validate_search_request( $request );
259	if ( is_wp_error( $validation ) ) {
260	return $validation;
261	}
262	list( $ids, $search_meta ) = $this->search_variation_ids( $request );
263	} elseif ( array() === array_filter( (array) $request->get_param( 'include' ) ) ) {
264	/*
265	* A bare collection request — no `include`, no discovery term — answers page one of the
266	* POS-servable set with WooCommerce's own pagination, exactly as its `get_items()` would.
267	*
268	* This used to be a 400. That refusal is why the client still counts variations on the
269	* FROZEN `wcpos/v1` lane — the single remaining v1 call in the app — because the census
270	* probes a collection route and reads `X-WP-Total`, and no v2 variations route could
271	* answer "how many". Refusing the question was never a safety property: `include` is a
272	* filter, and a collection route with no filter is a collection.
273	*/
274	list( $ids, $search_meta ) = $this->collection_page( $request );
275	} else {
276	/*
277	* The ask runs through the SAME query WooCommerce's own collection read builds
278	* (#1751): `parent::prepare_objects_query()` maps `include` to `post__in` and — in
279	* wc/v3's CRUD controller — applies `woocommerce_rest_product_variation_object_query`
280	* internally, so third-party query scoping reaches this lane like every other
281	* (hook-parity contract #1738). The collection and discovery lanes always had that
282	* property; this lane loaded ids directly and bypassed it. POS visibility and the
283	* publish gate ride the same args (layered in our override).
284	*
285	* The paging/ordering params are PINNED, not honoured: this lane answers a named
286	* ask, so `per_page` covers the whole ask, `offset`/`page` cannot skip any of it
287	* (a skipped id is absent from documents, which the client reads as "prune this
288	* id"), and `orderby=include` keeps WooCommerce from ordering by a meta key whose
289	* EXISTS join would silently drop every variation lacking that meta row. Pinning
290	* `orderby` also keeps the args complete for direct (non-dispatched) invocations,
291	* which carry no route defaults. Served order is the include order either way —
292	* the intersect below is the final authority.
293	*/
294	$include_ids = array_values( array_unique( array_map( 'intval', (array) $request->get_param( 'include' ) ) ) );
295	// Pins live on a QUERY-ONLY clone: the dispatched request stays exactly
296	// as the client sent it, for the serializer's prepare-filters and for
297	// anything downstream reading it after dispatch.
298	$query_request = clone $request;
299	$query_request->set_param( 'per_page', max( 1, count( $include_ids ) ) );
300	$query_request->set_param( 'page', 1 );
301	$query_request->set_param( 'offset', 0 );
302	$query_request->set_param( 'orderby', 'include' );
303	$query_request->set_param( 'order', 'asc' );
304	$args = $this->prepare_objects_query( $query_request );
305
306	/*
307	* The ask is a CEILING. WooCommerce's variations controller UNIONS some
308	* collection params into `post__in` (`on_sale=true` array-unions every on-sale
309	* id on top of the ask), so without this intersection a stray param would
310	* hydrate the whole store into the till. No request param or filter may widen
311	* the served set beyond the named ids — narrowing is fine, that is what the
312	* object_query filter and the visibility exclusion are for. An emptied ask pins
313	* to `array( 0 )`, the same never-matches sentinel Pos_Visibility uses.
314	*/
315	$post_in = array_values( array_intersect( array_map( 'intval', (array) ( $args['post__in'] ?? array() ) ), $include_ids ) );
316	$args['post__in'] = array() === $post_in ? array( 0 ) : $post_in;
317	$results = $this->get_objects( $args );
318
319	$allowed_ids = array();
320	foreach ( $results['objects'] as $object ) {
321	if ( $object instanceof WC_Product_Variation ) {
322	$allowed_ids[] = $object->get_id();
323	}
324	}
325	$ids = array_values( array_intersect( $include_ids, $allowed_ids ) );
326	}
327	_prime_post_caches( $ids, true, true );
328
329	// Hydrate through THE product assembly line (Product_Serializer), the same
330	// seam resolve/changes use (ADR 0003 — values come from the REST
331	// representation, never raw SQL). wc_get_product() returns a
332	// WC_Product_Variation for a variation id; the instanceof guard keeps a
333	// product id from being hydrated through this lane.
334	// Leg-3 (ADR 0014): attach each variation's stored 64-bit digest as `_rxdb_digest` so the client
335	// seeds its existence-reconcile manifest from this pull too (products get theirs via the proxy
336	// filter). Bulk-read once for the whole include set. A string — the digest exceeds int range.
337	// ::class, never the bare string: from inside this namespace
338	// class_exists( 'Digest_Index' ) probes the GLOBAL namespace and is
339	// forever false, so variation digests would never emit (review finding 3).
340	// Variations read the PRODUCTS id-space — one registry row owns both
341	// object types, so this lane cannot drift from the proxy lane's answer.
342	$digests = class_exists( Digest_Index::class )
343	? ( new Digest_Index() )->read_digests( 'products', $ids )
344	: array();
345
346	$serializer = new Product_Serializer();
347	// A CLONE of the live request, not a synthetic bare one (so prepare-filters
348	// see the real request context), and not the live request itself (the
349	// serializer stamps store scope and a per-variation `product_id` onto
350	// whatever it is handed; the dispatched request must leave this method as
351	// the client sent it).
352	$serialization_request = clone $request;
353	$documents = array();
354	foreach ( $ids as $id ) {
355	$variation = wc_get_product( $id );
356	if ( ! $variation instanceof WC_Product_Variation ) {
357	continue;
358	}
359	/*
360	* DISABLED variations are never hydrated — see the `post_status` note in
361	* prepare_objects_query(). The query-level publish gate covers ALL lanes, including
362	* `include`; this check only guards a status change between the id query and object load.
363	*
364	* `meta.requested` now counts the query-eligible ask: a disabled or query-filtered id is
365	* absent from $ids. The client's targeted-pull shortfall — absence from documents — is
366	* unchanged.
367	*/
368	if ( 'publish' !== $variation->get_status() ) {
369	continue;
370	}
371	$payload = $serializer->serialize( $variation, $serialization_request );
372	$document = array(
373	'id' => $id,
374	'parent_id' => (int) $variation->get_parent_id(),
375	'payload' => $payload,
376	);
377	if ( isset( $digests[ $id ] ) ) {
378	$document['_rxdb_digest'] = $digests[ $id ];
379	}
380	$documents[] = $document;
381	}
382
383	$meta = array(
384	'duration_ms' => round( ( microtime( true ) - $started ) * 1000, 3 ),
385	'requested' => \count( $ids ),
386	'returned' => \count( $documents ),
387	);
388	if ( null !== $search_meta ) {
389	$meta = array_merge( $meta, $search_meta );
390	}
391
392	$response = rest_ensure_response(
393	array(
394	'documents' => $documents,
395	'meta' => $meta,
396	)
397	);
398
399	/*
400	* The pagination WooCommerce would have sent.
401	*
402	* No v2 route emitted `X-WP-Total`/`X-WP-TotalPages` — including this one, the only one
403	* that paginates. The client asks for them on every v2 GET (the response envelope mirrors
404	* them into the body), so it has been receiving an empty mirror and falling back to
405	* short-page detection, which cannot tell "last page" from "the server truncated".
406	*/
407	if ( null !== $search_meta && $response instanceof WP_REST_Response ) {
408	$response->header( 'X-WP-Total', (string) $search_meta['total'] );
409	$response->header(
410	'X-WP-TotalPages',
411	(string) ( $search_meta['per_page'] > 0 ? (int) ceil( $search_meta['total'] / $search_meta['per_page'] ) : 0 )
412	);
413	}
414
415	return $response;
416	}
417
418	/**
419	* Reject search requests that could build excessively large SQL queries or offsets.
420	*
421	* @return true\|WP_Error
422	*/
423	private function validate_search_request( WP_REST_Request $request ) {
424	$sku = (string) ( $request->get_param( 'sku' ) ?? '' );
425	$skus = array_filter(
426	array_map( 'trim', explode( ',', $sku ) ),
427	static function ( string $term ): bool {
428	return '' !== $term;
429	}
430	);
431	if ( array() !== $skus ) {
432	$sku = implode( ',', $skus );
433	if ( self::MAX_SKU_LENGTH < \strlen( $sku ) ) {
434	return new WP_Error( 'woocommerce_pos_variations_search_limit_exceeded', 'sku must not exceed 4096 bytes', array( 'status' => 400 ) );
435	}
436	if ( self::MAX_SKU_TERMS < \count( $skus ) ) {
437	return new WP_Error( 'woocommerce_pos_variations_search_limit_exceeded', 'sku must not contain more than 100 comma-separated terms', array( 'status' => 400 ) );
438	}
439	} else {
440	$search = (string) $request->get_param( 'search' );
441	if ( self::MAX_SEARCH_LENGTH < \strlen( $search ) ) {
442	return new WP_Error( 'woocommerce_pos_variations_search_limit_exceeded', 'search must not exceed 256 bytes', array( 'status' => 400 ) );
443	}
444	$terms = (array) preg_split( '/\s+/', trim( $search ), -1, PREG_SPLIT_NO_EMPTY );
445	if ( self::MAX_SEARCH_TERMS < \count( $terms ) ) {
446	return new WP_Error( 'woocommerce_pos_variations_search_limit_exceeded', 'search must not contain more than 10 whitespace-separated terms', array( 'status' => 400 ) );
447	}
448	}
449
450	if ( self::MAX_PAGE < (int) $request->get_param( 'page' ) ) {
451	return new WP_Error( 'woocommerce_pos_variations_search_limit_exceeded', 'page must not exceed 1000', array( 'status' => 400 ) );
452	}
453
454	return true;
455	}
456
457	/**
458	* Apply the declared POS variation sorts to the SQL clauses.
459	*
460	* `posts_clauses` fires for EVERY WP_Query, so the body is guarded by post type and by
461	* the plan itself — it contributes nothing unless this request claimed one of the
462	* declared sorts.
463	*
464	* @param array $clauses Associative array of the clauses for the query.
465	* @param WP_Query $wp_query The WP_Query instance.
466	*
467	* @return array
468	*/
469	public function wcpos_posts_clauses( array $clauses, WP_Query $wp_query ): array {
470	if ( null === $this->wcpos_sort_request ) {
471	return $clauses;
472	}
473
474	$post_type = $wp_query->query_vars['post_type'] ?? null;
475	if ( 'product_variation' !== $post_type && ( ! \is_array( $post_type ) \|\| ! \in_array( 'product_variation', $post_type, true ) ) ) {
476	return $clauses;
477	}
478
479	$plan = Collection_Rules::for_request( 'variations', $this->wcpos_sort_request, self::WCPOS_SORT_PARAM_MAP );
480
481	return $plan->filter( Collection_Rules_Plan::HOOK_POSTS_CLAUSES, $clauses, $wp_query );
482	}
483
484	/**
485	* WooCommerce's collection params, plus the sort keys the POS grids offer.
486	*
487	* `orderby` is a validated enum. Appending here is what lets `prepare_objects_query()` act on
488	* these four — otherwise the request 400s during argument validation and the switch is dead
489	* code. 1.9.x extended the same enum for the same reason.
490	*/
491	public function get_collection_params() {
492	$params = parent::get_collection_params();
493
494	if ( isset( $params['orderby']['enum'] ) && \is_array( $params['orderby']['enum'] ) ) {
495	$params['orderby']['enum'] = array_values(
496	array_unique(
497	array_merge(
498	$params['orderby']['enum'],
499	Collection_Rules::orderby_enum( 'variations' )
500	)
501	)
502	);
503	}
504
505	return $params;
506	}
507
508	/**
509	* De-duplicate variation searches joined through matching meta rows.
510	*
511	* @param string $groupby Existing GROUP BY clause.
512	* @param WP_Query $query Query being filtered.
513	*/
514	public function group_search_results( string $groupby, WP_Query $query ): string {
515	global $wpdb;
516
517	return ! empty( $query->query_vars['wcpos_variation_search'] ) ? "{$wpdb->posts}.ID" : $groupby;
518	}
519
520	/**
521	* Does this discovery request still carry a term after normalization?
522	*
523	* `has_param()` is what selects discovery mode, and an empty or whitespace-only value passes
524	* it. This is the check that decides whether a query would actually be constrained.
525	*/
526	private function has_discovery_constraint( WP_REST_Request $request ): bool {
527	$sku = (string) ( $request->get_param( 'sku' ) ?? '' );
528	if ( '' !== trim( $sku, " \t\n\r\0\x0B," ) ) {
529	return true;
530	}
531
532	$search = (string) ( $request->get_param( 'search' ) ?? '' );
533
534	return array() !== (array) preg_split( '/\s+/', trim( $search ), -1, PREG_SPLIT_NO_EMPTY );
535	}
536
537	/**
538	* One page of the POS-servable variation collection, with its total.
539	*
540	* WooCommerce's query pair, same as {@see search_variation_ids()} — the only difference is that
541	* a bare collection request carries no discovery constraint to normalize away, so the
542	* blank-scan guard that turns `?search=%20` into zero rows must NOT apply here. Visibility and
543	* `post_status` narrowing both ride `prepare_objects_query()`, so this page counts exactly what
544	* the client is allowed to receive.
545	*
546	* @return array{0: array<int, int>, 1: array{total: int, page: int, per_page: int}}
547	*/
548	private function collection_page( WP_REST_Request $request ): array {
549	$per_page = max( 1, min( 100, (int) ( $request->get_param( 'per_page' ) ?? 10 ) ) );
550	$page = max( 1, (int) ( $request->get_param( 'page' ) ?? 1 ) );
551	$request->set_param( 'per_page', $per_page );
552	$request->set_param( 'page', $page );
553
554	$results = $this->get_objects( $this->prepare_objects_query( $request ) );
555
556	$ids = array();
557	foreach ( $results['objects'] as $object ) {
558	if ( $object instanceof WC_Product_Variation ) {
559	$ids[] = $object->get_id();
560	}
561	}
562
563	return array(
564	$ids,
565	array(
566	'total' => (int) ( $results['total'] ?? \count( $ids ) ),
567	'page' => $page,
568	'per_page' => $per_page,
569	),
570	);
571	}
572
573	/**
574	* Discover a page of published, POS-visible variation ids by SKU/barcode.
575	*
576	* The query is WooCommerce's — `prepare_objects_query()` + `get_objects()`, the same pair its
577	* own `get_items()` uses. This method previously hand-built the SQL: a `wp_posts`/`wp_postmeta`
578	* INNER JOIN with `LIKE` predicates assembled per (field, term) pair, a second COUNT(DISTINCT)
579	* query for the total, and the hidden-id exclusion spliced into the same placeholder list. All
580	* of it duplicated `WP_Query` — which is where such copies go wrong, quietly and later.
581	*
582	* @return array{0: array<int, int>, 1: array{total: int, page: int, per_page: int}}
583	*/
584	private function search_variation_ids( WP_REST_Request $request ): array {
585	$per_page = max( 1, min( 100, (int) ( $request->get_param( 'per_page' ) ?? 10 ) ) );
586	$page = max( 1, (int) ( $request->get_param( 'page' ) ?? 1 ) );
587	$request->set_param( 'per_page', $per_page );
588	$request->set_param( 'page', $page );
589
590	$query_args = $this->prepare_objects_query( $request );
591
592	/*
593	* A discovery request whose terms normalize away — `?sku=`, `?sku=,%20`, `?search=%20` —
594	* has no constraint left. Inherited, that query would return the FIRST PAGE OF EVERY
595	* VARIATION and advertise the catalogue-wide total; the replaced SQL deliberately used
596	* `1 = 0`. A blank scan must hydrate nothing, not everything.
597	*/
598	if ( ! $this->has_discovery_constraint( $request ) ) {
599	return array(
600	array(),
601	array(
602	'total' => 0,
603	'page' => $page,
604	'per_page' => $per_page,
605	),
606	);
607	}
608
609	add_filter( 'posts_groupby', array( $this, 'group_search_results' ), 10, 2 );
610	try {
611	$results = $this->get_objects( $query_args );
612	} finally {
613	remove_filter( 'posts_groupby', array( $this, 'group_search_results' ), 10 );
614	}
615
616	$ids = array();
617	foreach ( $results['objects'] as $object ) {
618	if ( $object instanceof WC_Product_Variation ) {
619	$ids[] = $object->get_id();
620	}
621	}
622
623	return array(
624	$ids,
625	array(
626	'total' => (int) ( $results['total'] ?? \count( $ids ) ),
627	'page' => $page,
628	'per_page' => $per_page,
629	),
630	);
631	}
632	}
633