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   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       * @var int
  27       */
  28      public static $max_posts = 15;
  29  
  30      /**
  31       * Instantiate.
  32       *
  33       * All custom functionality will be hooked into the "init" action.
  34       *
  35       * @since Twenty Fourteen 1.0
  36       */
  37  	public static function setup() {
  38          add_action( 'init', array( __CLASS__, 'init' ), 30 );
  39      }
  40  
  41      /**
  42       * Conditionally hook into WordPress.
  43       *
  44       * Theme must declare that they support this module by adding
  45       * add_theme_support( 'featured-content' ); during after_setup_theme.
  46       *
  47       * If no theme support is found there is no need to hook into WordPress.
  48       * We'll just return early instead.
  49       *
  50       * @since Twenty Fourteen 1.0
  51       */
  52  	public static function init() {
  53          $theme_support = get_theme_support( 'featured-content' );
  54  
  55          // Return early if theme does not support Featured Content.
  56          if ( ! $theme_support ) {
  57              return;
  58          }
  59  
  60          /*
  61           * An array of named arguments must be passed as the second parameter
  62           * of add_theme_support().
  63           */
  64          if ( ! isset( $theme_support[0] ) ) {
  65              return;
  66          }
  67  
  68          // Return early if "featured_content_filter" has not been defined.
  69          if ( ! isset( $theme_support[0]['featured_content_filter'] ) ) {
  70              return;
  71          }
  72  
  73          $filter = $theme_support[0]['featured_content_filter'];
  74  
  75          // Theme can override the number of max posts.
  76          if ( isset( $theme_support[0]['max_posts'] ) ) {
  77              self::$max_posts = absint( $theme_support[0]['max_posts'] );
  78          }
  79  
  80          add_filter( $filter, array( __CLASS__, 'get_featured_posts' ) );
  81          add_action( 'customize_register', array( __CLASS__, 'customize_register' ), 9 );
  82          add_action( 'admin_init', array( __CLASS__, 'register_setting' ) );
  83          add_action( 'switch_theme', array( __CLASS__, 'delete_transient' ) );
  84          add_action( 'save_post', array( __CLASS__, 'delete_transient' ) );
  85          add_action( 'delete_post_tag', array( __CLASS__, 'delete_post_tag' ) );
  86          add_action( 'customize_controls_enqueue_scripts', array( __CLASS__, 'enqueue_scripts' ) );
  87          add_action( 'pre_get_posts', array( __CLASS__, 'pre_get_posts' ) );
  88          add_action( 'wp_loaded', array( __CLASS__, 'wp_loaded' ) );
  89      }
  90  
  91      /**
  92       * Hide "featured" tag from the front end.
  93       *
  94       * Has to run on wp_loaded so that the preview filters of the Customizer
  95       * have a chance to alter the value.
  96       *
  97       * @since Twenty Fourteen 1.0
  98       */
  99  	public static function wp_loaded() {
 100          if ( self::get_setting( 'hide-tag' ) ) {
 101              add_filter( 'get_terms', array( __CLASS__, 'hide_featured_term' ), 10, 3 );
 102              add_filter( 'get_the_terms', array( __CLASS__, 'hide_the_featured_term' ), 10, 3 );
 103          }
 104      }
 105  
 106      /**
 107       * Get featured posts.
 108       *
 109       * @since Twenty Fourteen 1.0
 110       *
 111       * @return array Array of featured posts.
 112       */
 113  	public static function get_featured_posts() {
 114          $post_ids = self::get_featured_post_ids();
 115  
 116          // No need to query if there is are no featured posts.
 117          if ( empty( $post_ids ) ) {
 118              return array();
 119          }
 120  
 121          $featured_posts = get_posts(
 122              array(
 123                  'include'        => $post_ids,
 124                  'posts_per_page' => count( $post_ids ),
 125              )
 126          );
 127  
 128          return $featured_posts;
 129      }
 130  
 131      /**
 132       * Get featured post IDs
 133       *
 134       * This function will return the an array containing the
 135       * post IDs of all featured posts.
 136       *
 137       * Sets the "featured_content_ids" transient.
 138       *
 139       * @since Twenty Fourteen 1.0
 140       *
 141       * @return array Array of post IDs.
 142       */
 143  	public static function get_featured_post_ids() {
 144          // Get array of cached results if they exist.
 145          $featured_ids = get_transient( 'featured_content_ids' );
 146  
 147          if ( false === $featured_ids ) {
 148              $settings = self::get_setting();
 149              $term     = get_term_by( 'name', $settings['tag-name'], 'post_tag' );
 150  
 151              if ( $term ) {
 152                  // Query for featured posts.
 153                  $featured_ids = get_posts(
 154                      array(
 155                          'fields'           => 'ids',
 156                          'numberposts'      => self::$max_posts,
 157                          'suppress_filters' => false,
 158                          'tax_query'        => array(
 159                              array(
 160                                  'field'    => 'term_id',
 161                                  'taxonomy' => 'post_tag',
 162                                  'terms'    => $term->term_id,
 163                              ),
 164                          ),
 165                      )
 166                  );
 167              }
 168  
 169              // Get sticky posts if no Featured Content exists.
 170              if ( ! $featured_ids ) {
 171                  $featured_ids = self::get_sticky_posts();
 172              }
 173  
 174              set_transient( 'featured_content_ids', $featured_ids );
 175          }
 176  
 177          // Ensure correct format before return.
 178          return array_map( 'absint', $featured_ids );
 179      }
 180  
 181      /**
 182       * Return an array with IDs of posts maked as sticky.
 183       *
 184       * @since Twenty Fourteen 1.0
 185       *
 186       * @return array Array of sticky posts.
 187       */
 188  	public static function get_sticky_posts() {
 189          return array_slice( get_option( 'sticky_posts', array() ), 0, self::$max_posts );
 190      }
 191  
 192      /**
 193       * Delete featured content IDs transient.
 194       *
 195       * Hooks in the "save_post" action.
 196       *
 197       * @see Featured_Content::validate_settings().
 198       *
 199       * @since Twenty Fourteen 1.0
 200       */
 201  	public static function delete_transient() {
 202          delete_transient( 'featured_content_ids' );
 203      }
 204  
 205      /**
 206       * Exclude featured posts from the home page blog query.
 207       *
 208       * Filter the home page posts, and remove any featured post ID's from it.
 209       * Hooked onto the 'pre_get_posts' action, this changes the parameters of
 210       * the query before it gets any posts.
 211       *
 212       * @since Twenty Fourteen 1.0
 213       *
 214       * @param WP_Query $query WP_Query object.
 215       * @return WP_Query Possibly-modified WP_Query.
 216       */
 217  	public static function pre_get_posts( $query ) {
 218  
 219          // Bail if not home or not main query.
 220          if ( ! $query->is_home() || ! $query->is_main_query() ) {
 221              return;
 222          }
 223  
 224          // Bail if the blog page is not the front page.
 225          if ( 'posts' !== get_option( 'show_on_front' ) ) {
 226              return;
 227          }
 228  
 229          $featured = self::get_featured_post_ids();
 230  
 231          // Bail if no featured posts.
 232          if ( ! $featured ) {
 233              return;
 234          }
 235  
 236          // We need to respect post IDs already in the exclude list.
 237          $post__not_in = $query->get( 'post__not_in' );
 238  
 239          if ( ! empty( $post__not_in ) ) {
 240              $featured = array_merge( (array) $post__not_in, $featured );
 241              $featured = array_unique( $featured );
 242          }
 243  
 244          $query->set( 'post__not_in', $featured );
 245      }
 246  
 247      /**
 248       * Reset tag option when the saved tag is deleted.
 249       *
 250       * It's important to mention that the transient needs to be deleted,
 251       * too. While it may not be obvious by looking at the function alone,
 252       * the transient is deleted by Featured_Content::validate_settings().
 253       *
 254       * Hooks in the "delete_post_tag" action.
 255       *
 256       * @see Featured_Content::validate_settings().
 257       *
 258       * @since Twenty Fourteen 1.0
 259       *
 260       * @param int $tag_id The term_id of the tag that has been deleted.
 261       */
 262  	public static function delete_post_tag( $tag_id ) {
 263          $settings = self::get_setting();
 264  
 265          if ( empty( $settings['tag-id'] ) || $tag_id != $settings['tag-id'] ) {
 266              return;
 267          }
 268  
 269          $settings['tag-id'] = 0;
 270          $settings           = self::validate_settings( $settings );
 271          update_option( 'featured-content', $settings );
 272      }
 273  
 274      /**
 275       * Hide featured tag from displaying when global terms are queried from the front end.
 276       *
 277       * Hooks into the "get_terms" filter.
 278       *
 279       * @since Twenty Fourteen 1.0
 280       *
 281       * @param array $terms      List of term objects. This is the return value of get_terms().
 282       * @param array $taxonomies An array of taxonomy slugs.
 283       * @return array A filtered array of terms.
 284       *
 285       * @uses Featured_Content::get_setting()
 286       */
 287  	public static function hide_featured_term( $terms, $taxonomies, $args ) {
 288  
 289          // This filter is only appropriate on the front end.
 290          if ( is_admin() ) {
 291              return $terms;
 292          }
 293  
 294          // We only want to hide the featured tag.
 295          if ( ! in_array( 'post_tag', $taxonomies, true ) ) {
 296              return $terms;
 297          }
 298  
 299          // Bail if no terms were returned.
 300          if ( empty( $terms ) ) {
 301              return $terms;
 302          }
 303  
 304          // Bail if term objects are unavailable.
 305          if ( 'all' !== $args['fields'] ) {
 306              return $terms;
 307          }
 308  
 309          $settings = self::get_setting();
 310          foreach ( $terms as $order => $term ) {
 311              if ( ( $settings['tag-id'] === $term->term_id || $settings['tag-name'] === $term->name ) && 'post_tag' === $term->taxonomy ) {
 312                  unset( $terms[ $order ] );
 313              }
 314          }
 315  
 316          return $terms;
 317      }
 318  
 319      /**
 320       * Hide featured tag from display when terms associated with a post object
 321       * are queried from the front end.
 322       *
 323       * Hooks into the "get_the_terms" filter.
 324       *
 325       * @since Twenty Fourteen 1.0
 326       *
 327       * @param array $terms    A list of term objects. This is the return value of get_the_terms().
 328       * @param int   $id       The ID field for the post object that terms are associated with.
 329       * @param array $taxonomy An array of taxonomy slugs.
 330       * @return array Filtered array of terms.
 331       *
 332       * @uses Featured_Content::get_setting()
 333       */
 334  	public static function hide_the_featured_term( $terms, $id, $taxonomy ) {
 335  
 336          // This filter is only appropriate on the front end.
 337          if ( is_admin() ) {
 338              return $terms;
 339          }
 340  
 341          // Make sure we are in the correct taxonomy.
 342          if ( 'post_tag' !== $taxonomy ) {
 343              return $terms;
 344          }
 345  
 346          // No terms? Return early!
 347          if ( empty( $terms ) ) {
 348              return $terms;
 349          }
 350  
 351          $settings = self::get_setting();
 352          foreach ( $terms as $order => $term ) {
 353              if ( ( $settings['tag-id'] === $term->term_id || $settings['tag-name'] === $term->name ) && 'post_tag' === $term->taxonomy ) {
 354                  unset( $terms[ $term->term_id ] );
 355              }
 356          }
 357  
 358          return $terms;
 359      }
 360  
 361      /**
 362       * Register custom setting on the Settings -> Reading screen.
 363       *
 364       * @since Twenty Fourteen 1.0
 365       */
 366  	public static function register_setting() {
 367          register_setting( 'featured-content', 'featured-content', array( __CLASS__, 'validate_settings' ) );
 368      }
 369  
 370      /**
 371       * Add settings to the Customizer.
 372       *
 373       * @since Twenty Fourteen 1.0
 374       *
 375       * @param WP_Customize_Manager $wp_customize Customizer object.
 376       */
 377  	public static function customize_register( $wp_customize ) {
 378          $wp_customize->add_section(
 379              'featured_content',
 380              array(
 381                  'title'          => __( 'Featured Content', 'twentyfourteen' ),
 382                  'description'    => sprintf(
 383                      /* translators: 1: Featured tag editor URL, 2: Post editor URL. */
 384                      __( 'Use a <a href="%1$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' ),
 385                      esc_url( add_query_arg( 'tag', _x( 'featured', 'featured content default tag slug', 'twentyfourteen' ), admin_url( 'edit.php' ) ) ),
 386                      admin_url( 'edit.php?show_sticky=1' )
 387                  ),
 388                  'priority'       => 130,
 389                  'theme_supports' => 'featured-content',
 390              )
 391          );
 392  
 393          // Add Featured Content settings.
 394          $wp_customize->add_setting(
 395              'featured-content[tag-name]',
 396              array(
 397                  'default'              => _x( 'featured', 'featured content default tag slug', 'twentyfourteen' ),
 398                  'type'                 => 'option',
 399                  'sanitize_js_callback' => array( __CLASS__, 'delete_transient' ),
 400              )
 401          );
 402          $wp_customize->add_setting(
 403              'featured-content[hide-tag]',
 404              array(
 405                  'default'              => true,
 406                  'type'                 => 'option',
 407                  'sanitize_js_callback' => array( __CLASS__, 'delete_transient' ),
 408              )
 409          );
 410  
 411          // Add Featured Content controls.
 412          $wp_customize->add_control(
 413              'featured-content[tag-name]',
 414              array(
 415                  'label'    => __( 'Tag Name', 'twentyfourteen' ),
 416                  'section'  => 'featured_content',
 417                  'priority' => 20,
 418              )
 419          );
 420          $wp_customize->add_control(
 421              'featured-content[hide-tag]',
 422              array(
 423                  'label'    => __( 'Don&rsquo;t display tag on front end.', 'twentyfourteen' ),
 424                  'section'  => 'featured_content',
 425                  'type'     => 'checkbox',
 426                  'priority' => 30,
 427              )
 428          );
 429      }
 430  
 431      /**
 432       * Enqueue the tag suggestion script.
 433       *
 434       * @since Twenty Fourteen 1.0
 435       */
 436  	public static function enqueue_scripts() {
 437          wp_enqueue_script( 'featured-content-suggest', get_template_directory_uri() . '/js/featured-content-admin.js', array( 'jquery', 'suggest' ), '20131205', true );
 438      }
 439  
 440      /**
 441       * Get featured content settings.
 442       *
 443       * Get all settings recognized by this module. This function
 444       * will return all settings whether or not they have been stored
 445       * in the database yet. This ensures that all keys are available
 446       * at all times.
 447       *
 448       * In the event that you only require one setting, you may pass
 449       * its name as the first parameter to the function and only that
 450       * value will be returned.
 451       *
 452       * @since Twenty Fourteen 1.0
 453       *
 454       * @param string $key The key of a recognized setting.
 455       * @return mixed Array of all settings by default. A single value if passed as first parameter.
 456       */
 457  	public static function get_setting( $key = 'all' ) {
 458          $saved = (array) get_option( 'featured-content' );
 459  
 460          $defaults = array(
 461              'hide-tag' => 1,
 462              'tag-id'   => 0,
 463              'tag-name' => _x( 'featured', 'featured content default tag slug', 'twentyfourteen' ),
 464          );
 465  
 466          $options = wp_parse_args( $saved, $defaults );
 467          $options = array_intersect_key( $options, $defaults );
 468  
 469          if ( 'all' !== $key ) {
 470              return isset( $options[ $key ] ) ? $options[ $key ] : false;
 471          }
 472  
 473          return $options;
 474      }
 475  
 476      /**
 477       * Validate featured content settings.
 478       *
 479       * Make sure that all user supplied content is in an expected
 480       * format before saving to the database. This function will also
 481       * delete the transient set in Featured_Content::get_featured_content().
 482       *
 483       * @since Twenty Fourteen 1.0
 484       *
 485       * @param array $input Array of settings input.
 486       * @return array Validated settings output.
 487       */
 488  	public static function validate_settings( $input ) {
 489          $output = array();
 490  
 491          if ( empty( $input['tag-name'] ) ) {
 492              $output['tag-id'] = 0;
 493          } else {
 494              $term = get_term_by( 'name', $input['tag-name'], 'post_tag' );
 495  
 496              if ( $term ) {
 497                  $output['tag-id'] = $term->term_id;
 498              } else {
 499                  $new_tag = wp_create_tag( $input['tag-name'] );
 500  
 501                  if ( ! is_wp_error( $new_tag ) && isset( $new_tag['term_id'] ) ) {
 502                      $output['tag-id'] = $new_tag['term_id'];
 503                  }
 504              }
 505  
 506              $output['tag-name'] = $input['tag-name'];
 507          }
 508  
 509          $output['hide-tag'] = isset( $input['hide-tag'] ) && $input['hide-tag'] ? 1 : 0;
 510  
 511          // Delete the featured post IDs transient.
 512          self::delete_transient();
 513  
 514          return $output;
 515      }
 516  } // Featured_Content
 517  
 518  Featured_Content::setup();