/wp-includes/post.php

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<?php
/**
 * Post functions and post utility function.
 *
 * @package WordPress
 * @subpackage Post
 * @since 1.5.0
 */

//
// Post Type Registration
//

/**
 * Creates the initial post types when 'init' action is fired.
 *
 * @since 2.9.0
 */
function create_initial_post_types() {
	register_post_type( 'post', array(
		'labels' => array(
			'name_admin_bar' => _x( 'Post', 'add new on admin bar' ),
		),
		'public'  => true,
		'_builtin' => true, /* internal use only. don't use this when registering your own post type. */
		'_edit_link' => 'post.php?post=%d', /* internal use only. don't use this when registering your own post type. */
		'capability_type' => 'post',
		'map_meta_cap' => true,
		'hierarchical' => false,
		'rewrite' => false,
		'query_var' => false,
		'delete_with_user' => true,
		'supports' => array( 'title', 'editor', 'author', 'thumbnail', 'excerpt', 'trackbacks', 'custom-fields', 'comments', 'revisions', 'post-formats' ),
	) );

	register_post_type( 'page', array(
		'labels' => array(
			'name_admin_bar' => _x( 'Page', 'add new on admin bar' ),
		),
		'public' => true,
		'publicly_queryable' => false,
		'_builtin' => true, /* internal use only. don't use this when registering your own post type. */
		'_edit_link' => 'post.php?post=%d', /* internal use only. don't use this when registering your own post type. */
		'capability_type' => 'page',
		'map_meta_cap' => true,
		'hierarchical' => true,
		'rewrite' => false,
		'query_var' => false,
		'delete_with_user' => true,
		'supports' => array( 'title', 'editor', 'author', 'thumbnail', 'page-attributes', 'custom-fields', 'comments', 'revisions' ),
	) );

	register_post_type( 'attachment', array(
		'labels' => array(
			'name' => _x('Media', 'post type general name'),
			'name_admin_bar' => _x( 'Media', 'add new from admin bar' ),
			'add_new' => _x( 'Add New', 'add new media' ),
 			'edit_item' => __( 'Edit Media' ),
 			'view_item' => __( 'View Attachment Page' ),
		),
		'public' => true,
		'show_ui' => true,
		'_builtin' => true, /* internal use only. don't use this when registering your own post type. */
		'_edit_link' => 'post.php?post=%d', /* internal use only. don't use this when registering your own post type. */
		'capability_type' => 'post',
		'capabilities' => array(
			'create_posts' => 'upload_files',
		),
		'map_meta_cap' => true,
		'hierarchical' => false,
		'rewrite' => false,
		'query_var' => false,
		'show_in_nav_menus' => false,
		'delete_with_user' => true,
		'supports' => array( 'title', 'author', 'comments' ),
	) );
	add_post_type_support( 'attachment:audio', 'thumbnail' );
	add_post_type_support( 'attachment:video', 'thumbnail' );

	register_post_type( 'revision', array(
		'labels' => array(
			'name' => __( 'Revisions' ),
			'singular_name' => __( 'Revision' ),
		),
		'public' => false,
		'_builtin' => true, /* internal use only. don't use this when registering your own post type. */
		'_edit_link' => 'revision.php?revision=%d', /* internal use only. don't use this when registering your own post type. */
		'capability_type' => 'post',
		'map_meta_cap' => true,
		'hierarchical' => false,
		'rewrite' => false,
		'query_var' => false,
		'can_export' => false,
		'delete_with_user' => true,
		'supports' => array( 'author' ),
	) );

	register_post_type( 'nav_menu_item', array(
		'labels' => array(
			'name' => __( 'Navigation Menu Items' ),
			'singular_name' => __( 'Navigation Menu Item' ),
		),
		'public' => false,
		'_builtin' => true, /* internal use only. don't use this when registering your own post type. */
		'hierarchical' => false,
		'rewrite' => false,
		'delete_with_user' => false,
		'query_var' => false,
	) );

	register_post_status( 'publish', array(
		'label'       => _x( 'Published', 'post' ),
		'public'      => true,
		'_builtin'    => true, /* internal use only. */
		'label_count' => _n_noop( 'Published <span class="count">(%s)</span>', 'Published <span class="count">(%s)</span>' ),
	) );

	register_post_status( 'future', array(
		'label'       => _x( 'Scheduled', 'post' ),
		'protected'   => true,
		'_builtin'    => true, /* internal use only. */
		'label_count' => _n_noop('Scheduled <span class="count">(%s)</span>', 'Scheduled <span class="count">(%s)</span>' ),
	) );

	register_post_status( 'draft', array(
		'label'       => _x( 'Draft', 'post' ),
		'protected'   => true,
		'_builtin'    => true, /* internal use only. */
		'label_count' => _n_noop( 'Draft <span class="count">(%s)</span>', 'Drafts <span class="count">(%s)</span>' ),
	) );

	register_post_status( 'pending', array(
		'label'       => _x( 'Pending', 'post' ),
		'protected'   => true,
		'_builtin'    => true, /* internal use only. */
		'label_count' => _n_noop( 'Pending <span class="count">(%s)</span>', 'Pending <span class="count">(%s)</span>' ),
	) );

	register_post_status( 'private', array(
		'label'       => _x( 'Private', 'post' ),
		'private'     => true,
		'_builtin'    => true, /* internal use only. */
		'label_count' => _n_noop( 'Private <span class="count">(%s)</span>', 'Private <span class="count">(%s)</span>' ),
	) );

	register_post_status( 'trash', array(
		'label'       => _x( 'Trash', 'post' ),
		'internal'    => true,
		'_builtin'    => true, /* internal use only. */
		'label_count' => _n_noop( 'Trash <span class="count">(%s)</span>', 'Trash <span class="count">(%s)</span>' ),
		'show_in_admin_status_list' => true,
	) );

	register_post_status( 'auto-draft', array(
		'label'    => 'auto-draft',
		'internal' => true,
		'_builtin' => true, /* internal use only. */
	) );

	register_post_status( 'inherit', array(
		'label'    => 'inherit',
		'internal' => true,
		'_builtin' => true, /* internal use only. */
		'exclude_from_search' => false,
	) );
}
add_action( 'init', 'create_initial_post_types', 0 ); // highest priority

/**
 * Retrieve attached file path based on attachment ID.
 *
 * By default the path will go through the 'get_attached_file' filter, but
 * passing a true to the $unfiltered argument of get_attached_file() will
 * return the file path unfiltered.
 *
 * The function works by getting the single post meta name, named
 * '_wp_attached_file' and returning it. This is a convenience function to
 * prevent looking up the meta name and provide a mechanism for sending the
 * attached filename through a filter.
 *
 * @since 2.0.0
 *
 * @param int  $attachment_id Attachment ID.
 * @param bool $unfiltered    Optional. Whether to apply filters. Default false.
 * @return string|bool The file path to where the attached file should be, false otherwise.
 */
function get_attached_file( $attachment_id, $unfiltered = false ) {
	$file = get_post_meta( $attachment_id, '_wp_attached_file', true );
	// If the file is relative, prepend upload dir.
	if ( $file && 0 !== strpos($file, '/') && !preg_match('|^.:\\\|', $file) && ( ($uploads = wp_upload_dir()) && false === $uploads['error'] ) )
		$file = $uploads['basedir'] . "/$file";
	if ( $unfiltered )
		return $file;

	/**
	 * Filter the attached file based on the given ID.
	 *
	 * @since 2.1.0
	 *
	 * @param string $file          Path to attached file.
	 * @param int    $attachment_id Attachment ID.
	 */
	return apply_filters( 'get_attached_file', $file, $attachment_id );
}

/**
 * Update attachment file path based on attachment ID.
 *
 * Used to update the file path of the attachment, which uses post meta name
 * '_wp_attached_file' to store the path of the attachment.
 *
 * @since 2.1.0
 *
 * @param int    $attachment_id Attachment ID.
 * @param string $file          File path for the attachment.
 * @return bool True on success, false on failure.
 */
function update_attached_file( $attachment_id, $file ) {
	if ( !get_post( $attachment_id ) )
		return false;

	/**
	 * Filter the path to the attached file to update.
	 *
	 * @since 2.1.0
	 *
	 * @param string $file          Path to the attached file to update.
	 * @param int    $attachment_id Attachment ID.
	 */
	$file = apply_filters( 'update_attached_file', $file, $attachment_id );

	if ( $file = _wp_relative_upload_path( $file ) )
		return update_post_meta( $attachment_id, '_wp_attached_file', $file );
	else
		return delete_post_meta( $attachment_id, '_wp_attached_file' );
}

/**
 * Return relative path to an uploaded file.
 *
 * The path is relative to the current upload dir.
 *
 * @since 2.9.0
 *
 * @param string $path Full path to the file.
 * @return string Relative path on success, unchanged path on failure.
 */
function _wp_relative_upload_path( $path ) {
	$new_path = $path;

	$uploads = wp_upload_dir();
	if ( 0 === strpos( $new_path, $uploads['basedir'] ) ) {
			$new_path = str_replace( $uploads['basedir'], '', $new_path );
			$new_path = ltrim( $new_path, '/' );
	}

	/**
	 * Filter the relative path to an uploaded file.
	 *
	 * @since 2.9.0
	 *
	 * @param string $new_path Relative path to the file.
	 * @param string $path     Full path to the file.
	 */
	return apply_filters( '_wp_relative_upload_path', $new_path, $path );
}

/**
 * Retrieve all children of the post parent ID.
 *
 * Normally, without any enhancements, the children would apply to pages. In the
 * context of the inner workings of WordPress, pages, posts, and attachments
 * share the same table, so therefore the functionality could apply to any one
 * of them. It is then noted that while this function does not work on posts, it
 * does not mean that it won't work on posts. It is recommended that you know
 * what context you wish to retrieve the children of.
 *
 * Attachments may also be made the child of a post, so if that is an accurate
 * statement (which needs to be verified), it would then be possible to get
 * all of the attachments for a post. Attachments have since changed since
 * version 2.5, so this is most likely unaccurate, but serves generally as an
 * example of what is possible.
 *
 * The arguments listed as defaults are for this function and also of the
 * {@link get_posts()} function. The arguments are combined with the
 * get_children defaults and are then passed to the {@link get_posts()}
 * function, which accepts additional arguments. You can replace the defaults in
 * this function, listed below and the additional arguments listed in the
 * {@link get_posts()} function.
 *
 * The 'post_parent' is the most important argument and important attention
 * needs to be paid to the $args parameter. If you pass either an object or an
 * integer (number), then just the 'post_parent' is grabbed and everything else
 * is lost. If you don't specify any arguments, then it is assumed that you are
 * in The Loop and the post parent will be grabbed for from the current post.
 *
 * The 'post_parent' argument is the ID to get the children. The 'numberposts'
 * is the amount of posts to retrieve that has a default of '-1', which is
 * used to get all of the posts. Giving a number higher than 0 will only
 * retrieve that amount of posts.
 *
 * The 'post_type' and 'post_status' arguments can be used to choose what
 * criteria of posts to retrieve. The 'post_type' can be anything, but WordPress
 * post types are 'post', 'pages', and 'attachments'. The 'post_status'
 * argument will accept any post status within the write administration panels.
 *
 * @internal Claims made in the long description might be inaccurate.
 * @since 2.0.0
 *
 * @see get_posts()
 *
 * @param mixed  $args   Optional. User defined arguments for replacing the defaults. Default empty.
 * @param string $output Optional. Constant for return type. Accepts OBJECT, ARRAY_A, ARRAY_N.
 *                       Default OBJECt.
 * @return array Array of children, where the type of each element is determined by $output parameter.
 *               Empty array on failure.
 */
function get_children( $args = '', $output = OBJECT ) {
	$kids = array();
	if ( empty( $args ) ) {
		if ( isset( $GLOBALS['post'] ) ) {
			$args = array('post_parent' => (int) $GLOBALS['post']->post_parent );
		} else {
			return $kids;
		}
	} elseif ( is_object( $args ) ) {
		$args = array('post_parent' => (int) $args->post_parent );
	} elseif ( is_numeric( $args ) ) {
		$args = array('post_parent' => (int) $args);
	}

	$defaults = array(
		'numberposts' => -1, 'post_type' => 'any',
		'post_status' => 'any', 'post_parent' => 0,
	);

	$r = wp_parse_args( $args, $defaults );

	$children = get_posts( $r );

	if ( ! $children )
		return $kids;

	if ( ! empty( $r['fields'] ) )
		return $children;

	update_post_cache($children);

	foreach ( $children as $key => $child )
		$kids[$child->ID] = $children[$key];

	if ( $output == OBJECT ) {
		return $kids;
	} elseif ( $output == ARRAY_A ) {
		foreach ( (array) $kids as $kid )
			$weeuns[$kid->ID] = get_object_vars($kids[$kid->ID]);
		return $weeuns;
	} elseif ( $output == ARRAY_N ) {
		foreach ( (array) $kids as $kid )
			$babes[$kid->ID] = array_values(get_object_vars($kids[$kid->ID]));
		return $babes;
	} else {
		return $kids;
	}
}

/**
 * Get extended entry info (<!--more-->).
 *
 * There should not be any space after the second dash and before the word
 * 'more'. There can be text or space(s) after the word 'more', but won't be
 * referenced.
 *
 * The returned array has 'main', 'extended', and 'more_text' keys. Main has the text before
 * the `<!--more-->`. The 'extended' key has the content after the
 * `<!--more-->` comment. The 'more_text' key has the custom "Read More" text.
 *
 * @since 1.0.0
 *
 * @param string $post Post content.
 * @return array Post before ('main'), after ('extended'), and custom readmore ('more_text').
 */
function get_extended( $post ) {
	//Match the new style more links.
	if ( preg_match('/<!--more(.*?)?-->/', $post, $matches) ) {
		list($main, $extended) = explode($matches[0], $post, 2);
		$more_text = $matches[1];
	} else {
		$main = $post;
		$extended = '';
		$more_text = '';
	}

	//  leading and trailing whitespace.
	$main = preg_replace('/^[\s]*(.*)[\s]*$/', '\\1', $main);
	$extended = preg_replace('/^[\s]*(.*)[\s]*$/', '\\1', $extended);
	$more_text = preg_replace('/^[\s]*(.*)[\s]*$/', '\\1', $more_text);

	return array( 'main' => $main, 'extended' => $extended, 'more_text' => $more_text );
}

/**
 * Retrieves post data given a post ID or post object.
 *
 * See {@link sanitize_post()} for optional $filter values. Also, the parameter
 * $post, must be given as a variable, since it is passed by reference.
 *
 * @since 1.5.1
 *
 * @param int|WP_Post $post   Optional. Post ID or post object. Defaults to global $post.
 * @param string      $output Optional, default is Object. Accepts OBJECT, ARRAY_A, or ARRAY_N.
 *                            Default OBJECT.
 * @param string      $filter Optional. Type of filter to apply. Accepts 'raw', 'edit', 'db',
 *                            or 'display'. Default 'raw'.
 * @return WP_Post|null WP_Post on success or null on failure.
 */
function get_post( $post = null, $output = OBJECT, $filter = 'raw' ) {
	if ( empty( $post ) && isset( $GLOBALS['post'] ) )
		$post = $GLOBALS['post'];

	if ( is_a( $post, 'WP_Post' ) ) {
		$_post = $post;
	} elseif ( is_object( $post ) ) {
		if ( empty( $post->filter ) ) {
			$_post = sanitize_post( $post, 'raw' );
			$_post = new WP_Post( $_post );
		} elseif ( 'raw' == $post->filter ) {
			$_post = new WP_Post( $post );
		} else {
			$_post = WP_Post::get_instance( $post->ID );
		}
	} else {
		$_post = WP_Post::get_instance( $post );
	}

	if ( ! $_post )
		return null;

	$_post = $_post->filter( $filter );

	if ( $output == ARRAY_A )
		return $_post->to_array();
	elseif ( $output == ARRAY_N )
		return array_values( $_post->to_array() );

	return $_post;
}

/**
 * WordPress Post class.
 *
 * @since 3.5.0
 *
 */
final class WP_Post {

	/**
	 * Post ID.
	 *
	 * @var int
	 */
	public $ID;

	/**
	 * ID of post author.
	 *
	 * A numeric string, for compatibility reasons.
	 *
	 * @var string
	 */
	public $post_author = 0;

	/**
	 * The post's local publication time.
	 *
	 * @var string
	 */
	public $post_date = '0000-00-00 00:00:00';

	/**
	 * The post's GMT publication time.
	 *
	 * @var string
	 */
	public $post_date_gmt = '0000-00-00 00:00:00';

	/**
	 * The post's content.
	 *
	 * @var string
	 */
	public $post_content = '';

	/**
	 * The post's title.
	 *
	 * @var string
	 */
	public $post_title = '';

	/**
	 * The post's excerpt.
	 *
	 * @var string
	 */
	public $post_excerpt = '';

	/**
	 * The post's status.
	 *
	 * @var string
	 */
	public $post_status = 'publish';

	/**
	 * Whether comments are allowed.
	 *
	 * @var string
	 */
	public $comment_status = 'open';

	/**
	 * Whether pings are allowed.
	 *
	 * @var string
	 */
	public $ping_status = 'open';

	/**
	 * The post's password in plain text.
	 *
	 * @var string
	 */
	public $post_password = '';

	/**
	 * The post's slug.
	 *
	 * @var string
	 */
	public $post_name = '';

	/**
	 * URLs queued to be pinged.
	 *
	 * @var string
	 */
	public $to_ping = '';

	/**
	 * URLs that have been pinged.
	 *
	 * @var string
	 */
	public $pinged = '';

	/**
	 * The post's local modified time.
	 *
	 * @var string
	 */
	public $post_modified = '0000-00-00 00:00:00';

	/**
	 * The post's GMT modified time.
	 *
	 * @var string
	 */
	public $post_modified_gmt = '0000-00-00 00:00:00';

	/**
	 * A utility DB field for post content.
	 *
	 *
	 * @var string
	 */
	public $post_content_filtered = '';

	/**
	 * ID of a post's parent post.
	 *
	 * @var int
	 */
	public $post_parent = 0;

	/**
	 * The unique identifier for a post, not necessarily a URL, used as the feed GUID.
	 *
	 * @var string
	 */
	public $guid = '';

	/**
	 * A field used for ordering posts.
	 *
	 * @var int
	 */
	public $menu_order = 0;

	/**
	 * The post's type, like post or page.
	 *
	 * @var string
	 */
	public $post_type = 'post';

	/**
	 * An attachment's mime type.
	 *
	 * @var string
	 */
	public $post_mime_type = '';

	/**
	 * Cached comment count.
	 *
	 * A numeric string, for compatibility reasons.
	 *
	 * @var string
	 */
	public $comment_count = 0;

	/**
	 * Stores the post object's sanitization level.
	 *
	 * Does not correspond to a DB field.
	 *
	 * @var string
	 */
	public $filter;

	/**
	 * Retrieve WP_Post instance.
	 *
	 * @static
	 * @access public
	 *
	 * @param int $post_id Post ID.
	 * @return WP_Post|bool Post object, false otherwise.
	 */
	public static function get_instance( $post_id ) {
		global $wpdb;

		$post_id = (int) $post_id;
		if ( ! $post_id )
			return false;

		$_post = wp_cache_get( $post_id, 'posts' );

		if ( ! $_post ) {
			$_post = $wpdb->get_row( $wpdb->prepare( "SELECT * FROM $wpdb->posts WHERE ID = %d LIMIT 1", $post_id ) );

			if ( ! $_post )
				return false;

			$_post = sanitize_post( $_post, 'raw' );
			wp_cache_add( $_post->ID, $_post, 'posts' );
		} elseif ( empty( $_post->filter ) ) {
			$_post = sanitize_post( $_post, 'raw' );
		}

		return new WP_Post( $_post );
	}

	/**
	 * Constructor.
	 *
	 * @param WP_Post $post Post object.
	 */
	public function __construct( $post ) {
		foreach ( get_object_vars( $post ) as $key => $value )
			$this->$key = $value;
	}

	/**
	 * Isset-er.
	 *
	 * @param string $key Property to check if set.
	 * @return bool
	 */
	public function __isset( $key ) {
		if ( 'ancestors' == $key )
			return true;

		if ( 'page_template' == $key )
			return ( 'page' == $this->post_type );

		if ( 'post_category' == $key )
		   return true;

		if ( 'tags_input' == $key )
		   return true;

		return metadata_exists( 'post', $this->ID, $key );
	}

	/**
	 * Getter.
	 *
	 * @param string $key Key to get.
	 * @return array|mixed
	 */
	public function __get( $key ) {
		if ( 'page_template' == $key && $this->__isset( $key ) ) {
			return get_post_meta( $this->ID, '_wp_page_template', true );
		}

		if ( 'post_category' == $key ) {
			if ( is_object_in_taxonomy( $this->post_type, 'category' ) )
				$terms = get_the_terms( $this, 'category' );

			if ( empty( $terms ) )
				return array();

			return wp_list_pluck( $terms, 'term_id' );
		}

		if ( 'tags_input' == $key ) {
			if ( is_object_in_taxonomy( $this->post_type, 'post_tag' ) )
				$terms = get_the_terms( $this, 'post_tag' );

			if ( empty( $terms ) )
				return array();

			return wp_list_pluck( $terms, 'name' );
		}

		// Rest of the values need filtering.
		if ( 'ancestors' == $key )
			$value = get_post_ancestors( $this );
		else
			$value = get_post_meta( $this->ID, $key, true );

		if ( $this->filter )
			$value = sanitize_post_field( $key, $value, $this->ID, $this->filter );

		return $value;
	}

	/**
	 * {@Missing Summary}
	 *
	 * @param string $filter Filter.
	 * @return $this|array|bool|object|WP_Post
	 */
	public function filter( $filter ) {
		if ( $this->filter == $filter )
			return $this;

		if ( $filter == 'raw' )
			return self::get_instance( $this->ID );

		return sanitize_post( $this, $filter );
	}

	/**
	 * Convert object to array.
	 *
	 * @return array Object as array.
	 */
	public function to_array() {
		$post = get_object_vars( $this );

		foreach ( array( 'ancestors', 'page_template', 'post_category', 'tags_input' ) as $key ) {
			if ( $this->__isset( $key ) )
				$post[ $key ] = $this->__get( $key );
		}

		return $post;
	}
}

/**
 * Retrieve ancestors of a post.
 *
 * @since 2.5.0
 *
 * @param int|WP_Post $post Post ID or post object.
 * @return array Ancestor IDs or empty array if none are found.
 */
function get_post_ancestors( $post ) {
	$post = get_post( $post );

	if ( ! $post || empty( $post->post_parent ) || $post->post_parent == $post->ID )
		return array();

	$ancestors = array();

	$id = $ancestors[] = $post->post_parent;

	while ( $ancestor = get_post( $id ) ) {
		// Loop detection: If the ancestor has been seen before, break.
		if ( empty( $ancestor->post_parent ) || ( $ancestor->post_parent == $post->ID ) || in_array( $ancestor->post_parent, $ancestors ) )
			break;

		$id = $ancestors[] = $ancestor->post_parent;
	}

	return $ancestors;
}

/**
 * Retrieve data from a post field based on Post ID.
 *
 * Examples of the post field will be, 'post_type', 'post_status', 'post_content',
 * etc and based off of the post object property or key names.
 *
 * The context values are based off of the taxonomy filter functions and
 * supported values are found within those functions.
 *
 * @since 2.3.0
 *
 * @see sanitize_post_field()
 *
 * @param string      $field   Post field name.
 * @param int|WP_Post $post    Post ID or post object.
 * @param string      $context Optional. How to filter the field. Accepts 'raw', 'edit', 'db',
 *                             or 'display'. Default 'display'.
 * @return string The value of the post field on success, empty string on failure.
 */
function get_post_field( $field, $post, $context = 'display' ) {
	$post = get_post( $post );

	if ( !$post )
		return '';

	if ( !isset($post->$field) )
		return '';

	return sanitize_post_field($field, $post->$field, $post->ID, $context);
}

/**
 * Retrieve the mime type of an attachment based on the ID.
 *
 * This function can be used with any post type, but it makes more sense with
 * attachments.
 *
 * @since 2.0.0
 *
 * @param int|WP_Post $ID Optional. Post ID or post object. Default empty.
 * @return string|false The mime type on success, false on failure.
 */
function get_post_mime_type( $ID = '' ) {
	$post = get_post($ID);

	if ( is_object($post) )
		return $post->post_mime_type;

	return false;
}

/**
 * Retrieve the post status based on the Post ID.
 *
 * If the post ID is of an attachment, then the parent post status will be given
 * instead.
 *
 * @since 2.0.0
 *
 * @param int|WP_Post $ID Optional. Post ID or post object. Default empty.
 * @return string|false Post status on success, false on failure.
 */
function get_post_status( $ID = '' ) {
	$post = get_post($ID);

	if ( !is_object($post) )
		return false;

	if ( 'attachment' == $post->post_type ) {
		if ( 'private' == $post->post_status )
			return 'private';

		// Unattached attachments are assumed to be published.
		if ( ( 'inherit' == $post->post_status ) && ( 0 == $post->post_parent) )
			return 'publish';

		// Inherit status from the parent.
		if ( $post->post_parent && ( $post->ID != $post->post_parent ) ) {
			$parent_post_status = get_post_status( $post->post_parent );
			if ( 'trash' == $parent_post_status ) {
				return get_post_meta( $post->post_parent, '_wp_trash_meta_status', true );
			} else {
				return $parent_post_status;
			}
		}

	}

	return $post->post_status;
}

/**
 * Retrieve all of the WordPress supported post statuses.
 *
 * Posts have a limited set of valid status values, this provides the
 * post_status values and descriptions.
 *
 * @since 2.5.0
 *
 * @return array List of post statuses.
 */
function get_post_statuses() {
	$status = array(
		'draft'   => __( 'Draft' ),
		'pending' => __( 'Pending Review' ),
		'private' => __( 'Private' ),
		'publish' => __( 'Published' )
	);

	return $status;
}

/**
 * Retrieve all of the WordPress support page statuses.
 *
 * Pages have a limited set of valid status values, this provides the
 * post_status values and descriptions.
 *
 * @since 2.5.0
 *
 * @return array List of page statuses.
 */
function get_page_statuses() {
	$status = array(
		'draft'   => __( 'Draft' ),
		'private' => __( 'Private' ),
		'publish' => __( 'Published' )
	);

	return $status;
}

/**
 * Register a post status. Do not use before init.
 *
 * A simple function for creating or modifying a post status based on the
 * parameters given. The function will accept an array (second optional
 * parameter), along with a string for the post status name.
 *
 * Arguments prefixed with an _underscore shouldn't be used by plugins and themes.
 *
 * @since 3.0.0
 * @uses $wp_post_statuses Inserts new post status object into the list
 *
 * @param string $post_status Name of the post status.
 * @param array|string $args {
 *     Optional. Array or string of post status arguments.
 *
 *     @type bool|string $label                     A descriptive name for the post status marked
 *                                                  for translation. Defaults to value of $post_status.
 *     @type bool|array  $label_count               Descriptive text to use for nooped plurals.
 *                                                  Default array of $label, twice
 *     @type bool        $exclude_from_search       Whether to exclude posts with this post status
 *                                                  from search results. Default is value of $internal.
 *     @type bool        $_builtin                  Whether the status is built-in. Core-use only.
 *                                                  Default false.
 *     @type bool        $public                    Whether posts of this status should be shown
 *                                                  in the front end of the site. Default true.
 *     @type bool        $internal                  Whether the status is for internal use only.
 *                                                  Default false.
 *     @type bool        $protected                 Whether posts with this status should be protected.
 *                                                  Default false.
 *     @type bool        $private                   Whether posts with this status should be private.
 *                                                  Default false.
 *     @type bool        $publicly_queryable        Whether posts with this status should be publicly-
 *                                                  queryable. Default is value of $public.
 *     @type bool        $show_in_admin_all_list    Whether to include posts in the edit listing for
 *                                                  their post type. Default is value of $internal.
 *     @type bool        $show_in_admin_status_list Show in the list of statuses with post counts at
 *                                                  the top of the edit listings,
 *                                                  e.g. All (12) | Published (9) | My Custom Status (2)
 *                                                  Default is value of $internal.
 * }
 */
function register_post_status( $post_status, $args = array() ) {
	global $wp_post_statuses;

	if (!is_array($wp_post_statuses))
		$wp_post_statuses = array();

	// Args prefixed with an underscore are reserved for internal use.
	$defaults = array(
		'label' => false,
		'label_count' => false,
		'exclude_from_search' => null,
		'_builtin' => false,
		'public' => null,
		'internal' => null,
		'protected' => null,
		'private' => null,
		'publicly_queryable' => null,
		'show_in_admin_status_list' => null,
		'show_in_admin_all_list' => null,
	);
	$args = wp_parse_args($args, $defaults);
	$args = (object) $args;

	$post_status = sanitize_key($post_status);
	$args->name = $post_status;

	// Set various defaults.
	if ( null === $args->public && null === $args->internal && null === $args->protected && null === $args->private )
		$args->internal = true;

	if ( null === $args->public  )
		$args->public = false;

	if ( null === $args->private  )
		$args->private = false;

	if ( null === $args->protected  )
		$args->protected = false;

	if ( null === $args->internal  )
		$args->internal = false;

	if ( null === $args->publicly_queryable )
		$args->publicly_queryable = $args->public;

	if ( null === $args->exclude_from_search )
		$args->exclude_from_search = $args->internal;

	if ( null === $args->show_in_admin_all_list )
		$args->show_in_admin_all_list = !$args->internal;

	if ( null === $args->show_in_admin_status_list )
		$args->show_in_admin_status_list = !$args->internal;

	if ( false === $args->label )
		$args->label = $post_status;

	if ( false === $args->label_count )
		$args->label_count = array( $args->label, $args->label );

	$wp_post_statuses[$post_status] = $args;

	return $args;
}

/**
 * Retrieve a post status object by name.
 *
 * @since 3.0.0
 *
 * @global array $wp_post_statuses List of post statuses.
 *
 * @see register_post_status()
 *
 * @param string $post_status The name of a registered post status.
 * @return object A post status object.
 */
function get_post_status_object( $post_status ) {
	global $wp_post_statuses;

	if ( empty($wp_post_statuses[$post_status]) )
		return null;

	return $wp_post_statuses[$post_status];
}

/**
 * Get a list of post statuses.
 *
 * @since 3.0.0
 *
 * @global array $wp_post_statuses List of post statuses.
 *
 * @see register_post_status()
 *
 * @param array|string $args     Optional. Array or string of post status arguments to compare against
 *                               properties of the global `$wp_post_statuses objects`. Default empty array.
 * @param string       $output   Optional. The type of output to return, either 'names' or 'objects'. Default 'names'.
 * @param string       $operator Optional. The logical operation to perform. 'or' means only one element
 *                               from the array needs to match; 'and' means all elements must match.
 *                               Default 'and'.
 * @return array A list of post status names or objects.
 */
function get_post_stati( $args = array(), $output = 'names', $operator = 'and' ) {
	global $wp_post_statuses;

	$field = ('names' == $output) ? 'name' : false;

	return wp_filter_object_list($wp_post_statuses, $args, $operator, $field);
}

/**
 * Whether the post type is hierarchical.
 *
 * A false return value might also mean that the post type does not exist.
 *
 * @since 3.0.0
 *
 * @see get_post_type_object()
 *
 * @param string $post_type Post type name
 * @return bool Whether post type is hierarchical.
 */
function is_post_type_hierarchical( $post_type ) {
	if ( ! post_type_exists( $post_type ) )
		return false;

	$post_type = get_post_type_object( $post_type );
	return $post_type->hierarchical;
}

/**
 * Check if a post type is registered.
 *
 * @since 3.0.0
 *
 * @see get_post_type_object()
 *
 * @param string $post_type Post type name.
 * @return bool Whether post type is registered.
 */
function post_type_exists( $post_type ) {
	return (bool) get_post_type_object( $post_type );
}

/**
 * Retrieve the post type of the current post or of a given post.
 *
 * @since 2.1.0
 *
 * @param int|WP_Post $post Optional. Post ID or post object. Default is global $post.
 * @return string|false Post type on success, false on failure.
 */
function get_post_type( $post = null ) {
	if ( $post = get_post( $post ) )
		return $post->post_type;

	return false;
}

/**
 * Retrieve a post type object by name.
 *
 * @since 3.0.0
 *
 * @global array $wp_post_types List of post types.
 *
 * @see register_post_type()
 *
 * @param string $post_type The name of a registered post type.
 * @return object A post type object.
 */
function get_post_type_object( $post_type ) {
	global $wp_post_types;

	if ( empty($wp_post_types[$post_type]) )
		return null;

	return $wp_post_types[$post_type];
}

/**
 * Get a list of all registered post type objects.
 *
 * @since 2.9.0
 *
 * @global array $wp_post_types List of post types.
 *
 * @see register_post_type() for accepted arguments.
 *
 * @param array|string $args     Optional. An array of key => value arguments to match against
 *                               the post type objects. Default empty array.
 * @param string       $output   Optional. The type of output to return. Accepts post type 'names'
 *                               or 'objects'. Default 'names'.
 * @param string       $operator Optional. The logical operation to perform. 'or' means only one
 *                               element from the array needs to match; 'and' means all elements
 *                               must match. Accepts 'or' or 'and'. Default 'and'.
 * @return array A list of post type names or objects.
 */
function get_post_types( $args = array(), $output = 'names', $operator = 'and' ) {
	global $wp_post_types;

	$field = ('names' == $output) ? 'name' : false;

	return wp_filter_object_list($wp_post_types, $args, $operator, $field);
}

/**
 * Register a post type. Do not use before init.
 *
 * A function for creating or modifying a post type based on the
 * parameters given. The function will accept an array (second optional
 * parameter), along with a string for the post type name.
 *
 * @since 2.9.0
 *
 * @global array      $wp_post_types List of post types.
 * @global WP_Rewrite $wp_rewrite    Used for default feeds.
 * @global WP         $wp            Used to add query vars.
 *
 * @param string $post_type Post type key, must not exceed 20 characters.
 * @param array|string $args {
 *     Array or string of arguments for registering a post type.
 *
 *     @type string      $label                Name of the post type shown in the menu. Usually plural.
 *                                             Default is value of $labels['name'].
 *     @type array       $labels               An array of labels for this post type. If not set, post
 *                                             labels are inherited for non-hierarchical types and page
 *                                             labels for hierarchical ones. {@see get_post_type_labels()}.
 *     @type string      $description          A short descriptive summary of what the post type is.
 *                                             Default empty.
 *     @type bool        $public               Whether a post type is intended for use publicly either via
 *                                             the admin interface or by front-end users. While the default
 *                                             settings of $exclude_from_search, $publicly_queryable, $show_ui,
 *                                             and $show_in_nav_menus are inherited from public, each does not
 *                                             rely on this relationship and controls a very specific intention.
 *                                             Default false.
 *     @type bool        $hierarchical         Whether the post type is hierarchical (e.g. page). Default false.
 *     @type bool        $exclude_from_search  Whether to exclude posts with this post type from front end search
 *                                             results. Default is the opposite value of $public.
 *     @type bool        $publicly_queryable   Whether queries can be performed on the front end for the post type
 *                                             as part of {@see parse_request()}. Endpoints would include:
 *                                             * ?post_type={post_type_key}
 *                                             * ?{post_type_key}={single_post_slug}
 *                                             * ?{post_type_query_var}={single_post_slug}
 *                                             If not set, the default is inherited from $public.
 *     @type bool        $show_ui              Whether to generate a default UI for managing this post type in the
 *                                             admin. Default is value of $public.
 *     @type bool        $show_in_menu         Where to show the post type in the admin menu. To work, $show_ui
 *                                             must be true. If true, the post type is shown in its own top level
 *                                             menu. If false, no menu is shown. If a string of an existing top
 *                                             level menu (eg. 'tools.php' or 'edit.php?post_type=page'), the post
 *                                             type will be placed as a sub-menu of that.
 *                                             Default is value of $show_ui.
 *     @type bool        $show_in_nav_menus    Makes this post type available for selection in navigation menus.
 *                                             Default is value $public.
 *     @type bool        $show_in_admin_bar    Makes this post type available via the admin bar. Default is value
 *                                             of $show_in_menu.
 *     @type int         $menu_position        The position in the menu order the post type should appear. To work,
 *                                             $show_in_menu must be true. Default null (at the bottom).
 *     @type string      $menu_icon            The url to the icon to be used for this menu. Pass a base64-encoded
 *                                             SVG using a data URI, which will be colored to match the color scheme
 *                                             -- this should begin with 'data:image/svg+xml;base64,'. Pass the name
 *                                             of a Dashicons helper class to use a font icon, e.g.
 *                                             'dashicons-chart-pie'. Pass 'none' to leave div.wp-menu-image empty
 *                                             so an icon can be added via CSS. Defaults to use the posts icon.
 *     @type string      $capability_type      The string to use to build the read, edit, and delete capabilities.
 *                                             May be passed as an array to allow for alternative plurals when using
 *                                             this argument as a base to construct the capabilities, e.g.
 *                                             array('story', 'stories'). Default 'post'.
 *     @type array       $capabilities         Array of capabilities for this post type. $capability_type is used
 *                                             as a base to construct capabilities by default.
 *                                             {@see get_post_type_capabilities()}.
 *     @type bool        $map_meta_cap         Whether to use the internal default meta capability handling.
 *                                             Default false.
 *     @type array       $supports             An alias for calling {@see add_post_type_support()} directly.
 *                                             Defaults to array containing 'title' & 'editor'.
 *     @type callback    $register_meta_box_cb Provide a callback function that sets up the meta boxes for the
 *                                             edit form. Do remove_meta_box() and add_meta_box() calls in the
 *                                             callback. Default null.
 *     @type array       $taxonomies           An array of taxonomy identifiers that will be registered for the
 *                                             post type. Taxonomies can be registered later with
 *                                             {@see register_taxonomy()} or {@see register_taxonomy_for_object_type()}.
 *                                             Default empty array.
 *     @type bool|string $has_archive          Whether there should be post type archives, or if a string, the
 *                                             archive slug to use. Will generate the proper rewrite rules if
 *                                             $rewrite is enabled. Default false.
 *     @type bool|array  $rewrite              {
 *         Triggers the handling of rewrites for this post type. To prevent rewrite, set to false.
 *         Defaults to true, using $post_type as slug. To specify rewrite rules, an array can be
 *         passed with any of these keys:
 *
 *         @type string $slug       Customize the permastruct slug. Defaults to $post_type key.
 *         @type bool   $with_front Whether the permastruct should be prepended with WP_Rewrite::$front.
 *                                  Default true.
 *         @type bool   $feeds      Whether the feed permastruct should be built for this post type.
 *                                  Default is value of $has_archive.
 *         @type bool   $pages      Whether the permastruct should provide for pagination. Default true.
 *         @type const  $ep_mask    Endpoint mask to assign. If not specified and permalink_epmask is set,
 *                                  inherits from $permalink_epmask. If not specified and permalink_epmask
 *                                  is not set, defaults to EP_PERMALINK.
 *     }
 *     @type string|bool $query_var            Sets the query_var key for this post type. Defaults to $post_type
 *                                             key. If false, a post type cannot be loaded at
 *                                             ?{query_var}={post_slug}. If specified as a string, the query
 *                                             ?{query_var_string}={post_slug} will be valid.
 *     @type bool        $can_export           Whether to allow this post type to be exported. Default true.
 *     @type bool        $delete_with_user     Whether to delete posts of this type when deleting a user. If true,
 *                                             posts of this type belonging to the user will be moved to trash
 *                                             when then user is deleted. If false, posts of this type belonging
 *                                             to the user will *not* be trashed or deleted. If not set (the default),
 *                                             posts are trashed if post_type_supports('author'). Otherwise posts
 *                                             are not trashed or deleted. Default null.
 *     @type bool        $_builtin             FOR INTERNAL USE ONLY! True if this post type is a native or
 *                                             "built-in" post_type. Default false.
 *     @type string      $_edit_link           FOR INTERNAL USE ONLY! URL segment to use for edit link of
 *                                             this post type. Default 'post.php?post=%d'.
 * }
 * @return object|WP_Error The registered post type object, or an error object.
 */
function register_post_type( $post_type, $args = array() ) {
	global $wp_post_types, $wp_rewrite, $wp;

	if ( ! is_array( $wp_post_types ) )
		$wp_post_types = array();

	// Args prefixed with an underscore are reserved for internal use.
	$defaults = array(
		'labels'               => array(),
		'description'          => '',
		'public'               => false,
		'hierarchical'         => false,
		'exclude_from_search'  => null,
		'publicly_queryable'   => null,
		'show_ui'              => null,
		'show_in_menu'         => null,
		'show_in_nav_menus'    => null,
		'show_in_admin_bar'    => null,
		'menu_position'        => null,
		'menu_icon'            => null,
		'capability_type'      => 'post',
		'capabilities'         => array(),
		'map_meta_cap'         => null,
		'supports'             => array(),
		'register_meta_box_cb' => null,
		'taxonomies'           => array(),
		'has_archive'          => false,
		'rewrite'              => true,
		'query_var'            => true,
		'can_export'           => true,
		'delete_with_user'     => null,
		'_builtin'             => false,
		'_edit_link'           => 'post.php?post=%d',
	);
	$args = wp_parse_args( $args, $defaults );
	$args = (object) $args;

	$post_type = sanitize_key( $post_type );
	$args->name = $post_type;

	if ( strlen( $post_type ) > 20 ) {
		_doing_it_wrong( __FUNCTION__, __( 'Post types cannot exceed 20 characters in length' ), '4.0' );
		return new WP_Error( 'post_type_too_long', __( 'Post types cannot exceed 20 characters in length' ) );
	}

	// If not set, default to the setting for public.
	if ( null === $args->publicly_queryable )
		$args->publicly_queryable = $args->public;

	// If not set, default to the setting for public.
	if ( null === $args->show_ui )
		$args->show_ui = $args->public;

	// If not set, default to the setting for show_ui.
	if ( null === $args->show_in_menu || ! $args->show_ui )
		$args->show_in_menu = $args->show_ui;

	// If not set, default to the whether the full UI is shown.
	if ( null === $args->show_in_admin_bar )
		$args->show_in_admin_bar = (bool) $args->show_in_menu;

	// If not set, default to the setting for public.
	if ( null === $args->show_in_nav_menus )
		$args->show_in_nav_menus = $args->public;

	// If not set, default to true if not public, false if public.
	if ( null === $args->exclude_from_search )
		$args->exclude_from_search = !$args->public;

	// Back compat with quirky handling in version 3.0. #14122.
	if ( empty( $args->capabilities ) && null === $args->map_meta_cap && in_array( $args->capability_type, array( 'post', 'page' ) ) )
		$args->map_meta_cap = true;

	// If not set, default to false.
	if ( null === $args->map_meta_cap )
		$args->map_meta_cap = false;

	$args->cap = get_post_type_capabilities( $args );
	unset( $args->capabilities );

	if ( is_array( $args->capability_type ) )
		$args->capability_type = $args->capability_type[0];

	if ( ! empty( $args->supports ) ) {
		add_post_type_support( $post_type, $args->supports );
		unset( $args->supports );
	} elseif ( false !== $args->supports ) {
		// Add default features
		add_post_type_support( $post_type, array( 'title', 'editor' ) );
	}

	if ( false !== $args->query_var && ! empty( $wp ) ) {
		if ( true === $args->query_var )
			$args->query_var = $post_type;
		else
			$args->query_var = sanitize_title_with_dashes( $args->query_var );
		$wp->add_query_var( $args->query_var );
	}

	if ( false !== $args->rewrite && ( is_admin() || '' != get_option( 'permalink_structure' ) ) ) {
		if ( ! is_array( $args->rewrite ) )
			$args->rewrite = array();
		if ( empty( $args->rewrite['slug'] ) )
			$args->rewrite['slug'] = $post_type;
		if ( ! isset( $args->rewrite['with_front'] ) )
			$args->rewrite['with_front'] = true;
		if ( ! isset( $args->rewrite['pages'] ) )
			$args->rewrite['pages'] = true;
		if ( ! isset( $args->rewrite['feeds'] ) || ! $args->has_archive )
			$args->rewrite['feeds'] = (bool) $args->has_archive;
		if ( ! isset( $args->rewrite['ep_mask'] ) ) {
			if ( isset( $args->permalink_epmask ) )
				$args->rewrite['ep_mask'] = $args->permalink_epmask;
			else
				$args->rewrite['ep_mask'] = EP_PERMALINK;
		}

		if ( $args->hierarchical )
			add_rewrite_tag( "%$post_type%", '(.+?)', $args->query_var ? "{$args->query_var}=" : "post_type=$post_type&pagename=" );
		else
			add_rewrite_tag( "%$post_type%", '([^/]+)', $args->query_var ? "{$args->query_var}=" : "post_type=$post_type&name=" );

		if ( $args->has_archive ) {
			$archive_slug = $args->has_archive === true ? $args->rewrite['slug'] : $args->has_archive;
			if ( $args->rewrite['with_front'] )
				$archive_slug = substr( $wp_rewrite->front, 1 ) . $archive_slug;
			else
				$archive_slug = $wp_rewrite->root . $archive_slug;

			add_rewrite_rule( "{$archive_slug}/?$", "index.php?post_type=$post_type", 'top' );
			if ( $args->rewrite['feeds'] && $wp_rewrite->feeds ) {
				$feeds = '(' . trim( implode( '|', $wp_rewrite->feeds ) ) . ')';
				add_rewrite_rule( "{$archive_slug}/feed/$feeds/?$", "index.php?post_type=$post_type" . '&feed=$matches[1]', 'top' );
				add_rewrite_rule( "{$archive_slug}/$feeds/?$", "index.php?post_type=$post_type" . '&feed=$matches[1]', 'top' );
			}
			if ( $args->rewrite['pages'] )
				add_rewrite_rule( "{$archive_slug}/{$wp_rewrite->pagination_base}/([0-9]{1,})/?$", "index.php?post_type=$post_type" . '&paged=$matches[1]', 'top' );
		}

		$permastruct_args = $args->rewrite;
		$permastruct_args['feed'] = $permastruct_args['feeds'];
		add_permastruct( $post_type, "{$args->rewrite['slug']}/%$post_type%", $permastruct_args );
	}

	// Register the post type meta box if a custom callback was specified.
	if ( $args->register_meta_box_cb )
		add_action( 'add_meta_boxes_' . $post_type, $args->register_meta_box_cb, 10, 1 );

	$args->labels = get_post_type_labels( $args );
	$args->label = $args->labels->name;

	$wp_post_types[ $post_type ] = $args;

	add_action( 'future_' . $post_type, '_future_post_hook', 5, 2 );

	foreach ( $args->taxonomies as $taxonomy ) {
		register_taxonomy_for_object_type( $taxonomy, $post_type );
	}

	/**
	 * Fires after a post type is registered.
	 *
	 * @since 3.3.0
	 *
	 * @param string $post_type Post type.
	 * @param object $args      Arguments used to register the post type.
	 */
	do_action( 'registered_post_type', $post_type, $args );

	return $args;
}

/**
 * Build an object with all …

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