WordPress 3.8
[autoinstalls/wordpress.git] / wp-content / themes / twentyfourteen / inc / featured-content.php
1 <?php
2 /**
3  * Twenty Fourteen Featured Content
4  *
5  * This module allows you to define a subset of posts to be displayed
6  * in the theme's Featured Content area.
7  *
8  * For maximum compatibility with different methods of posting users
9  * will designate a featured post tag to associate posts with. Since
10  * this tag now has special meaning beyond that of a normal tags, users
11  * will have the ability to hide it from the front-end of their site.
12  */
13 class Featured_Content {
14
15         /**
16          * The maximum number of posts a Featured Content area can contain.
17          *
18          * We define a default value here but themes can override
19          * this by defining a "max_posts" entry in the second parameter
20          * passed in the call to add_theme_support( 'featured-content' ).
21          *
22          * @see Featured_Content::init()
23          *
24          * @since Twenty Fourteen 1.0
25          *
26          * @static
27          * @access public
28          * @var int
29          */
30         public static $max_posts = 15;
31
32         /**
33          * Instantiate.
34          *
35          * All custom functionality will be hooked into the "init" action.
36          *
37          * @static
38          * @access public
39          * @since Twenty Fourteen 1.0
40          */
41         public static function setup() {
42                 add_action( 'init', array( __CLASS__, 'init' ), 30 );
43         }
44
45         /**
46          * Conditionally hook into WordPress.
47          *
48          * Theme must declare that they support this module by adding
49          * add_theme_support( 'featured-content' ); during after_setup_theme.
50          *
51          * If no theme support is found there is no need to hook into WordPress.
52          * We'll just return early instead.
53          *
54          * @static
55          * @access public
56          * @since Twenty Fourteen 1.0
57          */
58         public static function init() {
59                 $theme_support = get_theme_support( 'featured-content' );
60
61                 // Return early if theme does not support Featured Content.
62                 if ( ! $theme_support ) {
63                         return;
64                 }
65
66                 /*
67                  * An array of named arguments must be passed as the second parameter
68                  * of add_theme_support().
69                  */
70                 if ( ! isset( $theme_support[0] ) ) {
71                         return;
72                 }
73
74                 // Return early if "featured_content_filter" has not been defined.
75                 if ( ! isset( $theme_support[0]['featured_content_filter'] ) ) {
76                         return;
77                 }
78
79                 $filter = $theme_support[0]['featured_content_filter'];
80
81                 // Theme can override the number of max posts.
82                 if ( isset( $theme_support[0]['max_posts'] ) ) {
83                         self::$max_posts = absint( $theme_support[0]['max_posts'] );
84                 }
85
86                 add_filter( $filter,                              array( __CLASS__, 'get_featured_posts' )    );
87                 add_action( 'customize_register',                 array( __CLASS__, 'customize_register' ), 9 );
88                 add_action( 'admin_init',                         array( __CLASS__, 'register_setting'   )    );
89                 add_action( 'save_post',                          array( __CLASS__, 'delete_transient'   )    );
90                 add_action( 'delete_post_tag',                    array( __CLASS__, 'delete_post_tag'    )    );
91                 add_action( 'customize_controls_enqueue_scripts', array( __CLASS__, 'enqueue_scripts'    )    );
92                 add_action( 'pre_get_posts',                      array( __CLASS__, 'pre_get_posts'      )    );
93                 add_action( 'wp_loaded',                          array( __CLASS__, 'wp_loaded'          )    );
94         }
95
96         /**
97          * Hide "featured" tag from the front-end.
98          *
99          * Has to run on wp_loaded so that the preview filters of the customizer
100          * have a chance to alter the value.
101          *
102          * @static
103          * @access public
104          * @since Twenty Fourteen 1.0
105          */
106         public static function wp_loaded() {
107                 if ( self::get_setting( 'hide-tag' ) ) {
108                         add_filter( 'get_terms',     array( __CLASS__, 'hide_featured_term'     ), 10, 2 );
109                         add_filter( 'get_the_terms', array( __CLASS__, 'hide_the_featured_term' ), 10, 3 );
110                 }
111         }
112
113         /**
114          * Get featured posts.
115          *
116          * @static
117          * @access public
118          * @since Twenty Fourteen 1.0
119          *
120          * @return array Array of featured posts.
121          */
122         public static function get_featured_posts() {
123                 $post_ids = self::get_featured_post_ids();
124
125                 // No need to query if there is are no featured posts.
126                 if ( empty( $post_ids ) ) {
127                         return array();
128                 }
129
130                 $featured_posts = get_posts( array(
131                         'include'        => $post_ids,
132                         'posts_per_page' => count( $post_ids ),
133                 ) );
134
135                 return $featured_posts;
136         }
137
138         /**
139          * Get featured post IDs
140          *
141          * This function will return the an array containing the
142          * post IDs of all featured posts.
143          *
144          * Sets the "featured_content_ids" transient.
145          *
146          * @static
147          * @access public
148          * @since Twenty Fourteen 1.0
149          *
150          * @return array Array of post IDs.
151          */
152         public static function get_featured_post_ids() {
153                 // Return array of cached results if they exist.
154                 $featured_ids = get_transient( 'featured_content_ids' );
155                 if ( ! empty( $featured_ids ) ) {
156                         return array_map( 'absint', (array) $featured_ids );
157                 }
158
159                 $settings = self::get_setting();
160
161                 // Return sticky post ids if no tag name is set.
162                 $term = get_term_by( 'name', $settings['tag-name'], 'post_tag' );
163                 if ( $term ) {
164                         $tag = $term->term_id;
165                 } else {
166                         return self::get_sticky_posts();
167                 }
168
169                 // Query for featured posts.
170                 $featured = get_posts( array(
171                         'numberposts' => $settings['quantity'],
172                         'tax_query'   => array(
173                                 array(
174                                         'field'    => 'term_id',
175                                         'taxonomy' => 'post_tag',
176                                         'terms'    => $tag,
177                                 ),
178                         ),
179                 ) );
180
181                 // Return array with sticky posts if no Featured Content exists.
182                 if ( ! $featured ) {
183                         return self::get_sticky_posts();
184                 }
185
186                 // Ensure correct format before save/return.
187                 $featured_ids = wp_list_pluck( (array) $featured, 'ID' );
188                 $featured_ids = array_map( 'absint', $featured_ids );
189
190                 set_transient( 'featured_content_ids', $featured_ids );
191
192                 return $featured_ids;
193         }
194
195         /**
196          * Return an array with IDs of posts maked as sticky.
197          *
198          * @static
199          * @access public
200          * @since Twenty Fourteen 1.0
201          *
202          * @return array Array of sticky posts.
203          */
204         public static function get_sticky_posts() {
205                 $settings = self::get_setting();
206                 return array_slice( get_option( 'sticky_posts', array() ), 0, $settings['quantity'] );
207         }
208
209         /**
210          * Delete featured content ids transient.
211          *
212          * Hooks in the "save_post" action.
213          *
214          * @see Featured_Content::validate_settings().
215          *
216          * @static
217          * @access public
218          * @since Twenty Fourteen 1.0
219          */
220         public static function delete_transient() {
221                 delete_transient( 'featured_content_ids' );
222         }
223
224         /**
225          * Exclude featured posts from the home page blog query.
226          *
227          * Filter the home page posts, and remove any featured post ID's from it.
228          * Hooked onto the 'pre_get_posts' action, this changes the parameters of
229          * the query before it gets any posts.
230          *
231          * @static
232          * @access public
233          * @since Twenty Fourteen 1.0
234          *
235          * @param WP_Query $query WP_Query object.
236          * @return WP_Query Possibly-modified WP_Query.
237          */
238         public static function pre_get_posts( $query ) {
239
240                 // Bail if not home or not main query.
241                 if ( ! $query->is_home() || ! $query->is_main_query() ) {
242                         return;
243                 }
244
245                 $page_on_front = get_option( 'page_on_front' );
246
247                 // Bail if the blog page is not the front page.
248                 if ( ! empty( $page_on_front ) ) {
249                         return;
250                 }
251
252                 $featured = self::get_featured_post_ids();
253
254                 // Bail if no featured posts.
255                 if ( ! $featured ) {
256                         return;
257                 }
258
259                 // We need to respect post ids already in the blacklist.
260                 $post__not_in = $query->get( 'post__not_in' );
261
262                 if ( ! empty( $post__not_in ) ) {
263                         $featured = array_merge( (array) $post__not_in, $featured );
264                         $featured = array_unique( $featured );
265                 }
266
267                 $query->set( 'post__not_in', $featured );
268         }
269
270         /**
271          * Reset tag option when the saved tag is deleted.
272          *
273          * It's important to mention that the transient needs to be deleted,
274          * too. While it may not be obvious by looking at the function alone,
275          * the transient is deleted by Featured_Content::validate_settings().
276          *
277          * Hooks in the "delete_post_tag" action.
278          *
279          * @see Featured_Content::validate_settings().
280          *
281          * @static
282          * @access public
283          * @since Twenty Fourteen 1.0
284          *
285          * @param int $tag_id The term_id of the tag that has been deleted.
286          * @return void
287          */
288         public static function delete_post_tag( $tag_id ) {
289                 $settings = self::get_setting();
290
291                 if ( empty( $settings['tag-id'] ) || $tag_id != $settings['tag-id'] ) {
292                         return;
293                 }
294
295                 $settings['tag-id'] = 0;
296                 $settings = self::validate_settings( $settings );
297                 update_option( 'featured-content', $settings );
298         }
299
300         /**
301          * Hide featured tag from displaying when global terms are queried from the front-end.
302          *
303          * Hooks into the "get_terms" filter.
304          *
305          * @static
306          * @access public
307          * @since Twenty Fourteen 1.0
308          *
309          * @param array $terms      List of term objects. This is the return value of get_terms().
310          * @param array $taxonomies An array of taxonomy slugs.
311          * @return array A filtered array of terms.
312          *
313          * @uses Featured_Content::get_setting()
314          */
315         public static function hide_featured_term( $terms, $taxonomies ) {
316
317                 // This filter is only appropriate on the front-end.
318                 if ( is_admin() ) {
319                         return $terms;
320                 }
321
322                 // We only want to hide the featured tag.
323                 if ( ! in_array( 'post_tag', $taxonomies ) ) {
324                         return $terms;
325                 }
326
327                 // Bail if no terms were returned.
328                 if ( empty( $terms ) ) {
329                         return $terms;
330                 }
331
332                 foreach( $terms as $order => $term ) {
333                         if ( self::get_setting( 'tag-id' ) == $term->term_id && 'post_tag' == $term->taxonomy ) {
334                                 unset( $terms[ $order ] );
335                         }
336                 }
337
338                 return $terms;
339         }
340
341         /**
342          * Hide featured tag from display when terms associated with a post object
343          * are queried from the front-end.
344          *
345          * Hooks into the "get_the_terms" filter.
346          *
347          * @static
348          * @access public
349          * @since Twenty Fourteen 1.0
350          *
351          * @param array $terms    A list of term objects. This is the return value of get_the_terms().
352          * @param int   $id       The ID field for the post object that terms are associated with.
353          * @param array $taxonomy An array of taxonomy slugs.
354          * @return array Filtered array of terms.
355          *
356          * @uses Featured_Content::get_setting()
357          */
358         public static function hide_the_featured_term( $terms, $id, $taxonomy ) {
359
360                 // This filter is only appropriate on the front-end.
361                 if ( is_admin() ) {
362                         return $terms;
363                 }
364
365                 // Make sure we are in the correct taxonomy.
366                 if ( 'post_tag' != $taxonomy ) {
367                         return $terms;
368                 }
369
370                 // No terms? Return early!
371                 if ( empty( $terms ) ) {
372                         return $terms;
373                 }
374
375                 foreach( $terms as $order => $term ) {
376                         if ( self::get_setting( 'tag-id' ) == $term->term_id ) {
377                                 unset( $terms[ $term->term_id ] );
378                         }
379                 }
380
381                 return $terms;
382         }
383
384         /**
385          * Register custom setting on the Settings -> Reading screen.
386          *
387          * @static
388          * @access public
389          * @since Twenty Fourteen 1.0
390          *
391          * @return void
392          */
393         public static function register_setting() {
394                 register_setting( 'featured-content', 'featured-content', array( __CLASS__, 'validate_settings' ) );
395         }
396
397         /**
398          * Add settings to the Customizer.
399          *
400          * @static
401          * @access public
402          * @since Twenty Fourteen 1.0
403          *
404          * @param WP_Customize_Manager $wp_customize Theme Customizer object.
405          */
406         public static function customize_register( $wp_customize ) {
407                 $wp_customize->add_section( 'featured_content', array(
408                         'title'          => __( 'Featured Content', 'twentyfourteen' ),
409                         'description'    => sprintf( __( 'Use the <a href="%1$s">"featured" tag</a> to feature your posts. You can change this to a tag of your choice; if no posts match the tag, <a href="%2$s">sticky posts</a> will be displayed instead.', 'twentyfourteen' ), admin_url( '/edit.php?tag=featured' ), admin_url( '/edit.php?show_sticky=1' ) ),
410                         'priority'       => 130,
411                         'theme_supports' => 'featured-content',
412                 ) );
413
414                 // Add Featured Content settings.
415                 $wp_customize->add_setting( 'featured-content[tag-name]', array(
416                         'default'              => 'featured',
417                         'type'                 => 'option',
418                         'sanitize_js_callback' => array( __CLASS__, 'delete_transient' ),
419                 ) );
420                 $wp_customize->add_setting( 'featured-content[hide-tag]', array(
421                         'default'              => true,
422                         'type'                 => 'option',
423                         'sanitize_js_callback' => array( __CLASS__, 'delete_transient' ),
424                 ) );
425
426                 // Add Featured Content controls.
427                 $wp_customize->add_control( 'featured-content[tag-name]', array(
428                         'label'    => __( 'Tag Name', 'twentyfourteen' ),
429                         'section'  => 'featured_content',
430                         'priority' => 20,
431                 ) );
432                 $wp_customize->add_control( 'featured-content[hide-tag]', array(
433                         'label'    => __( 'Don&rsquo;t display tag on front end.', 'twentyfourteen' ),
434                         'section'  => 'featured_content',
435                         'type'     => 'checkbox',
436                         'priority' => 30,
437                 ) );
438         }
439
440         /**
441          * Enqueue the tag suggestion script.
442          *
443          * @static
444          * @access public
445          * @since Twenty Fourteen 1.0
446          */
447         public static function enqueue_scripts() {
448                 wp_enqueue_script( 'featured-content-suggest', get_template_directory_uri() . '/js/featured-content-admin.js', array( 'jquery', 'suggest' ), '20131022', true );
449         }
450
451         /**
452          * Get featured content settings.
453          *
454          * Get all settings recognized by this module. This function
455          * will return all settings whether or not they have been stored
456          * in the database yet. This ensures that all keys are available
457          * at all times.
458          *
459          * In the event that you only require one setting, you may pass
460          * its name as the first parameter to the function and only that
461          * value will be returned.
462          *
463          * @static
464          * @access public
465          * @since Twenty Fourteen 1.0
466          *
467          * @param string $key The key of a recognized setting.
468          * @return mixed Array of all settings by default. A single value if passed as first parameter.
469          */
470         public static function get_setting( $key = 'all' ) {
471                 $saved = (array) get_option( 'featured-content' );
472
473                 $defaults = array(
474                         'hide-tag' => 1,
475                         'quantity' => 6,
476                         'tag-id'   => 0,
477                         'tag-name' => 'featured',
478                 );
479
480                 $options = wp_parse_args( $saved, $defaults );
481                 $options = array_intersect_key( $options, $defaults );
482                 $options['quantity'] = self::sanitize_quantity( $options['quantity'] );
483
484                 if ( 'all' != $key ) {
485                         return isset( $options[ $key ] ) ? $options[ $key ] : false;
486                 }
487
488                 return $options;
489         }
490
491         /**
492          * Validate featured content settings.
493          *
494          * Make sure that all user supplied content is in an expected
495          * format before saving to the database. This function will also
496          * delete the transient set in Featured_Content::get_featured_content().
497          *
498          * @static
499          * @access public
500          * @since Twenty Fourteen 1.0
501          *
502          * @param array $input Array of settings input.
503          * @return array Validated settings output.
504          */
505         public static function validate_settings( $input ) {
506                 $output = array();
507
508                 if ( empty( $input['tag-name'] ) ) {
509                         $output['tag-id'] = 0;
510                 } else {
511                         $term = get_term_by( 'name', $input['tag-name'], 'post_tag' );
512
513                         if ( $term ) {
514                                 $output['tag-id'] = $term->term_id;
515                         } else {
516                                 $new_tag = wp_create_tag( $input['tag-name'] );
517
518                                 if ( ! is_wp_error( $new_tag ) && isset( $new_tag['term_id'] ) ) {
519                                         $output['tag-id'] = $new_tag['term_id'];
520                                 }
521                         }
522
523                         $output['tag-name'] = $input['tag-name'];
524                 }
525
526                 if ( isset( $input['quantity'] ) ) {
527                         $output['quantity'] = self::sanitize_quantity( $input['quantity'] );
528                 }
529
530                 $output['hide-tag'] = isset( $input['hide-tag'] ) && $input['hide-tag'] ? 1 : 0;
531
532                 // Delete the featured post ids transient.
533                 self::delete_transient();
534
535                 return $output;
536         }
537
538         /**
539          * Sanitize quantity of featured posts.
540          *
541          * @static
542          * @access public
543          * @since Twenty Fourteen 1.0
544          *
545          * @param int $input The value to sanitize.
546          * @return int A number between 1 and FeaturedContent::$max_posts.
547          */
548         public static function sanitize_quantity( $input ) {
549                 $quantity = absint( $input );
550
551                 if ( $quantity > self::$max_posts ) {
552                         $quantity = self::$max_posts;
553                 } else if ( 1 > $quantity ) {
554                         $quantity = 1;
555                 }
556
557                 return $quantity;
558         }
559
560 } // Featured_Content
561
562 Featured_Content::setup();