WordPress 4.0
[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( 'switch_theme',                       array( __CLASS__, 'delete_transient'   )    );
90                 add_action( 'save_post',                          array( __CLASS__, 'delete_transient'   )    );
91                 add_action( 'delete_post_tag',                    array( __CLASS__, 'delete_post_tag'    )    );
92                 add_action( 'customize_controls_enqueue_scripts', array( __CLASS__, 'enqueue_scripts'    )    );
93                 add_action( 'pre_get_posts',                      array( __CLASS__, 'pre_get_posts'      )    );
94                 add_action( 'wp_loaded',                          array( __CLASS__, 'wp_loaded'          )    );
95         }
96
97         /**
98          * Hide "featured" tag from the front-end.
99          *
100          * Has to run on wp_loaded so that the preview filters of the customizer
101          * have a chance to alter the value.
102          *
103          * @static
104          * @access public
105          * @since Twenty Fourteen 1.0
106          */
107         public static function wp_loaded() {
108                 if ( self::get_setting( 'hide-tag' ) ) {
109                         add_filter( 'get_terms',     array( __CLASS__, 'hide_featured_term'     ), 10, 3 );
110                         add_filter( 'get_the_terms', array( __CLASS__, 'hide_the_featured_term' ), 10, 3 );
111                 }
112         }
113
114         /**
115          * Get featured posts.
116          *
117          * @static
118          * @access public
119          * @since Twenty Fourteen 1.0
120          *
121          * @return array Array of featured posts.
122          */
123         public static function get_featured_posts() {
124                 $post_ids = self::get_featured_post_ids();
125
126                 // No need to query if there is are no featured posts.
127                 if ( empty( $post_ids ) ) {
128                         return array();
129                 }
130
131                 $featured_posts = get_posts( array(
132                         'include'        => $post_ids,
133                         'posts_per_page' => count( $post_ids ),
134                 ) );
135
136                 return $featured_posts;
137         }
138
139         /**
140          * Get featured post IDs
141          *
142          * This function will return the an array containing the
143          * post IDs of all featured posts.
144          *
145          * Sets the "featured_content_ids" transient.
146          *
147          * @static
148          * @access public
149          * @since Twenty Fourteen 1.0
150          *
151          * @return array Array of post IDs.
152          */
153         public static function get_featured_post_ids() {
154                 // Get array of cached results if they exist.
155                 $featured_ids = get_transient( 'featured_content_ids' );
156
157                 if ( false === $featured_ids ) {
158                         $settings = self::get_setting();
159                         $term     = get_term_by( 'name', $settings['tag-name'], 'post_tag' );
160
161                         if ( $term ) {
162                                 // Query for featured posts.
163                                 $featured_ids = get_posts( array(
164                                         'fields'           => 'ids',
165                                         'numberposts'      => self::$max_posts,
166                                         'suppress_filters' => false,
167                                         'tax_query'        => array(
168                                                 array(
169                                                         'field'    => 'term_id',
170                                                         'taxonomy' => 'post_tag',
171                                                         'terms'    => $term->term_id,
172                                                 ),
173                                         ),
174                                 ) );
175                         }
176
177                         // Get sticky posts if no Featured Content exists.
178                         if ( ! $featured_ids ) {
179                                 $featured_ids = self::get_sticky_posts();
180                         }
181
182                         set_transient( 'featured_content_ids', $featured_ids );
183                 }
184
185                 // Ensure correct format before return.
186                 return array_map( 'absint', $featured_ids );
187         }
188
189         /**
190          * Return an array with IDs of posts maked as sticky.
191          *
192          * @static
193          * @access public
194          * @since Twenty Fourteen 1.0
195          *
196          * @return array Array of sticky posts.
197          */
198         public static function get_sticky_posts() {
199                 return array_slice( get_option( 'sticky_posts', array() ), 0, self::$max_posts );
200         }
201
202         /**
203          * Delete featured content ids transient.
204          *
205          * Hooks in the "save_post" action.
206          *
207          * @see Featured_Content::validate_settings().
208          *
209          * @static
210          * @access public
211          * @since Twenty Fourteen 1.0
212          */
213         public static function delete_transient() {
214                 delete_transient( 'featured_content_ids' );
215         }
216
217         /**
218          * Exclude featured posts from the home page blog query.
219          *
220          * Filter the home page posts, and remove any featured post ID's from it.
221          * Hooked onto the 'pre_get_posts' action, this changes the parameters of
222          * the query before it gets any posts.
223          *
224          * @static
225          * @access public
226          * @since Twenty Fourteen 1.0
227          *
228          * @param WP_Query $query WP_Query object.
229          * @return WP_Query Possibly-modified WP_Query.
230          */
231         public static function pre_get_posts( $query ) {
232
233                 // Bail if not home or not main query.
234                 if ( ! $query->is_home() || ! $query->is_main_query() ) {
235                         return;
236                 }
237
238                 $page_on_front = get_option( 'page_on_front' );
239
240                 // Bail if the blog page is not the front page.
241                 if ( ! empty( $page_on_front ) ) {
242                         return;
243                 }
244
245                 $featured = self::get_featured_post_ids();
246
247                 // Bail if no featured posts.
248                 if ( ! $featured ) {
249                         return;
250                 }
251
252                 // We need to respect post ids already in the blacklist.
253                 $post__not_in = $query->get( 'post__not_in' );
254
255                 if ( ! empty( $post__not_in ) ) {
256                         $featured = array_merge( (array) $post__not_in, $featured );
257                         $featured = array_unique( $featured );
258                 }
259
260                 $query->set( 'post__not_in', $featured );
261         }
262
263         /**
264          * Reset tag option when the saved tag is deleted.
265          *
266          * It's important to mention that the transient needs to be deleted,
267          * too. While it may not be obvious by looking at the function alone,
268          * the transient is deleted by Featured_Content::validate_settings().
269          *
270          * Hooks in the "delete_post_tag" action.
271          *
272          * @see Featured_Content::validate_settings().
273          *
274          * @static
275          * @access public
276          * @since Twenty Fourteen 1.0
277          *
278          * @param int $tag_id The term_id of the tag that has been deleted.
279          */
280         public static function delete_post_tag( $tag_id ) {
281                 $settings = self::get_setting();
282
283                 if ( empty( $settings['tag-id'] ) || $tag_id != $settings['tag-id'] ) {
284                         return;
285                 }
286
287                 $settings['tag-id'] = 0;
288                 $settings = self::validate_settings( $settings );
289                 update_option( 'featured-content', $settings );
290         }
291
292         /**
293          * Hide featured tag from displaying when global terms are queried from the front-end.
294          *
295          * Hooks into the "get_terms" filter.
296          *
297          * @static
298          * @access public
299          * @since Twenty Fourteen 1.0
300          *
301          * @param array $terms      List of term objects. This is the return value of get_terms().
302          * @param array $taxonomies An array of taxonomy slugs.
303          * @return array A filtered array of terms.
304          *
305          * @uses Featured_Content::get_setting()
306          */
307         public static function hide_featured_term( $terms, $taxonomies, $args ) {
308
309                 // This filter is only appropriate on the front-end.
310                 if ( is_admin() ) {
311                         return $terms;
312                 }
313
314                 // We only want to hide the featured tag.
315                 if ( ! in_array( 'post_tag', $taxonomies ) ) {
316                         return $terms;
317                 }
318
319                 // Bail if no terms were returned.
320                 if ( empty( $terms ) ) {
321                         return $terms;
322                 }
323
324                 // Bail if term objects are unavailable.
325                 if ( 'all' != $args['fields'] ) {
326                         return $terms;
327                 }
328
329                 $settings = self::get_setting();
330                 foreach( $terms as $order => $term ) {
331                         if ( ( $settings['tag-id'] === $term->term_id || $settings['tag-name'] === $term->name ) && 'post_tag' === $term->taxonomy ) {
332                                 unset( $terms[ $order ] );
333                         }
334                 }
335
336                 return $terms;
337         }
338
339         /**
340          * Hide featured tag from display when terms associated with a post object
341          * are queried from the front-end.
342          *
343          * Hooks into the "get_the_terms" filter.
344          *
345          * @static
346          * @access public
347          * @since Twenty Fourteen 1.0
348          *
349          * @param array $terms    A list of term objects. This is the return value of get_the_terms().
350          * @param int   $id       The ID field for the post object that terms are associated with.
351          * @param array $taxonomy An array of taxonomy slugs.
352          * @return array Filtered array of terms.
353          *
354          * @uses Featured_Content::get_setting()
355          */
356         public static function hide_the_featured_term( $terms, $id, $taxonomy ) {
357
358                 // This filter is only appropriate on the front-end.
359                 if ( is_admin() ) {
360                         return $terms;
361                 }
362
363                 // Make sure we are in the correct taxonomy.
364                 if ( 'post_tag' != $taxonomy ) {
365                         return $terms;
366                 }
367
368                 // No terms? Return early!
369                 if ( empty( $terms ) ) {
370                         return $terms;
371                 }
372
373                 $settings = self::get_setting();
374                 foreach( $terms as $order => $term ) {
375                         if ( ( $settings['tag-id'] === $term->term_id || $settings['tag-name'] === $term->name ) && 'post_tag' === $term->taxonomy ) {
376                                 unset( $terms[ $term->term_id ] );
377                         }
378                 }
379
380                 return $terms;
381         }
382
383         /**
384          * Register custom setting on the Settings -> Reading screen.
385          *
386          * @static
387          * @access public
388          * @since Twenty Fourteen 1.0
389          */
390         public static function register_setting() {
391                 register_setting( 'featured-content', 'featured-content', array( __CLASS__, 'validate_settings' ) );
392         }
393
394         /**
395          * Add settings to the Customizer.
396          *
397          * @static
398          * @access public
399          * @since Twenty Fourteen 1.0
400          *
401          * @param WP_Customize_Manager $wp_customize Theme Customizer object.
402          */
403         public static function customize_register( $wp_customize ) {
404                 $wp_customize->add_section( 'featured_content', array(
405                         'title'          => __( 'Featured Content', 'twentyfourteen' ),
406                         'description'    => sprintf( __( 'Use a <a href="%1$s">tag</a> to feature your posts. If no posts match the tag, <a href="%2$s">sticky posts</a> will be displayed instead.', 'twentyfourteen' ),
407                                 esc_url( add_query_arg( 'tag', _x( 'featured', 'featured content default tag slug', 'twentyfourteen' ), admin_url( 'edit.php' ) ) ),
408                                 admin_url( 'edit.php?show_sticky=1' )
409                         ),
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'              => _x( 'featured', 'featured content default tag slug', 'twentyfourteen' ),
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                         'tag-id'   => 0,
476                         'tag-name' => _x( 'featured', 'featured content default tag slug', 'twentyfourteen' ),
477                 );
478
479                 $options = wp_parse_args( $saved, $defaults );
480                 $options = array_intersect_key( $options, $defaults );
481
482                 if ( 'all' != $key ) {
483                         return isset( $options[ $key ] ) ? $options[ $key ] : false;
484                 }
485
486                 return $options;
487         }
488
489         /**
490          * Validate featured content settings.
491          *
492          * Make sure that all user supplied content is in an expected
493          * format before saving to the database. This function will also
494          * delete the transient set in Featured_Content::get_featured_content().
495          *
496          * @static
497          * @access public
498          * @since Twenty Fourteen 1.0
499          *
500          * @param array $input Array of settings input.
501          * @return array Validated settings output.
502          */
503         public static function validate_settings( $input ) {
504                 $output = array();
505
506                 if ( empty( $input['tag-name'] ) ) {
507                         $output['tag-id'] = 0;
508                 } else {
509                         $term = get_term_by( 'name', $input['tag-name'], 'post_tag' );
510
511                         if ( $term ) {
512                                 $output['tag-id'] = $term->term_id;
513                         } else {
514                                 $new_tag = wp_create_tag( $input['tag-name'] );
515
516                                 if ( ! is_wp_error( $new_tag ) && isset( $new_tag['term_id'] ) ) {
517                                         $output['tag-id'] = $new_tag['term_id'];
518                                 }
519                         }
520
521                         $output['tag-name'] = $input['tag-name'];
522                 }
523
524                 $output['hide-tag'] = isset( $input['hide-tag'] ) && $input['hide-tag'] ? 1 : 0;
525
526                 // Delete the featured post ids transient.
527                 self::delete_transient();
528
529                 return $output;
530         }
531 } // Featured_Content
532
533 Featured_Content::setup();