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();