lar( $resource_value ) ) {
				continue;
			}

			// Ignore non-supported attributes.
			$non_supported_attributes = array( 'as', 'crossorigin', 'href', 'imagesrcset', 'imagesizes', 'type', 'media', 'fetchpriority' );
			if ( ! in_array( $resource_key, $non_supported_attributes, true ) && ! is_numeric( $resource_key ) ) {
				continue;
			}

			// imagesrcset only usable when preloading image, ignore otherwise.
			if ( ( 'imagesrcset' === $resource_key ) && ( ! isset( $unique_resource['as'] ) || ( 'image' !== $unique_resource['as'] ) ) ) {
				continue;
			}

			// imagesizes only usable when preloading image and imagesrcset present, ignore otherwise.
			if ( ( 'imagesizes' === $resource_key ) &&
				( ! isset( $unique_resource['as'] ) || ( 'image' !== $unique_resource['as'] ) || ! isset( $unique_resource['imagesrcset'] ) )
			) {
				continue;
			}

			$resource_value = ( 'href' === $resource_key ) ? esc_url( $resource_value, array( 'http', 'https' ) ) : esc_attr( $resource_value );

			if ( ! is_string( $resource_key ) ) {
				$html .= " $resource_value";
			} else {
				$html .= " $resource_key='$resource_value'";
			}
		}
		$html = trim( $html );

		printf( "<link rel='preload' %s />\n", $html );
	}
}

/**
 * Retrieves a list of unique hosts of all enqueued scripts and styles.
 *
 * @since 4.6.0
 *
 * @global WP_Scripts $wp_scripts The WP_Scripts object for printing scripts.
 * @global WP_Styles  $wp_styles  The WP_Styles object for printing styles.
 *
 * @return string[] A list of unique hosts of enqueued scripts and styles.
 */
function wp_dependencies_unique_hosts() {
	global $wp_scripts, $wp_styles;

	$unique_hosts = array();

	foreach ( array( $wp_scripts, $wp_styles ) as $dependencies ) {
		if ( $dependencies instanceof WP_Dependencies && ! empty( $dependencies->queue ) ) {
			foreach ( $dependencies->queue as $handle ) {
				if ( ! isset( $dependencies->registered[ $handle ] ) ) {
					continue;
				}

				/* @var _WP_Dependency $dependency */
				$dependency = $dependencies->registered[ $handle ];
				$parsed     = wp_parse_url( $dependency->src );

				if ( ! empty( $parsed['host'] )
					&& ! in_array( $parsed['host'], $unique_hosts, true ) && $parsed['host'] !== $_SERVER['SERVER_NAME']
				) {
					$unique_hosts[] = $parsed['host'];
				}
			}
		}
	}

	return $unique_hosts;
}

/**
 * Determines whether the user can access the visual editor.
 *
 * Checks if the user can access the visual editor and that it's supported by the user's browser.
 *
 * @since 2.0.0
 *
 * @global bool $wp_rich_edit Whether the user can access the visual editor.
 * @global bool $is_gecko     Whether the browser is Gecko-based.
 * @global bool $is_opera     Whether the browser is Opera.
 * @global bool $is_safari    Whether the browser is Safari.
 * @global bool $is_chrome    Whether the browser is Chrome.
 * @global bool $is_IE        Whether the browser is Internet Explorer.
 * @global bool $is_edge      Whether the browser is Microsoft Edge.
 *
 * @return bool True if the user can access the visual editor, false otherwise.
 */
function user_can_richedit() {
	global $wp_rich_edit, $is_gecko, $is_opera, $is_safari, $is_chrome, $is_IE, $is_edge;

	if ( ! isset( $wp_rich_edit ) ) {
		$wp_rich_edit = false;

		if ( 'true' === get_user_option( 'rich_editing' ) || ! is_user_logged_in() ) { // Default to 'true' for logged out users.
			if ( $is_safari ) {
				$wp_rich_edit = ! wp_is_mobile() || ( preg_match( '!AppleWebKit/(\d+)!', $_SERVER['HTTP_USER_AGENT'], $match ) && (int) $match[1] >= 534 );
			} elseif ( $is_IE ) {
				$wp_rich_edit = str_contains( $_SERVER['HTTP_USER_AGENT'], 'Trident/7.0;' );
			} elseif ( $is_gecko || $is_chrome || $is_edge || ( $is_opera && ! wp_is_mobile() ) ) {
				$wp_rich_edit = true;
			}
		}
	}

	/**
	 * Filters whether the user can access the visual editor.
	 *
	 * @since 2.1.0
	 *
	 * @param bool $wp_rich_edit Whether the user can access the visual editor.
	 */
	return apply_filters( 'user_can_richedit', $wp_rich_edit );
}

/**
 * Finds out which editor should be displayed by default.
 *
 * Works out which of the editors to display as the current editor for a
 * user. The 'html' setting is for the "Text" editor tab.
 *
 * @since 2.5.0
 *
 * @return string Either 'tinymce', 'html', or 'test'
 */
function wp_default_editor() {
	$r = user_can_richedit() ? 'tinymce' : 'html'; // Defaults.
	if ( wp_get_current_user() ) { // Look for cookie.
		$ed = get_user_setting( 'editor', 'tinymce' );
		$r  = ( in_array( $ed, array( 'tinymce', 'html', 'test' ), true ) ) ? $ed : $r;
	}

	/**
	 * Filters which editor should be displayed by default.
	 *
	 * @since 2.5.0
	 *
	 * @param string $r Which editor should be displayed by default. Either 'tinymce', 'html', or 'test'.
	 */
	return apply_filters( 'wp_default_editor', $r );
}

/**
 * Renders an editor.
 *
 * Using this function is the proper way to output all needed components for both TinyMCE and Quicktags.
 * _WP_Editors should not be used directly. See https://core.trac.wordpress.org/ticket/17144.
 *
 * NOTE: Once initialized the TinyMCE editor cannot be safely moved in the DOM. For that reason
 * running wp_editor() inside of a meta box is not a good idea unless only Quicktags is used.
 * On the post edit screen several actions can be used to include additional editors
 * containing TinyMCE: 'edit_page_form', 'edit_form_advanced' and 'dbx_post_sidebar'.
 * See https://core.trac.wordpress.org/ticket/19173 for more information.
 *
 * @see _WP_Editors::editor()
 * @see _WP_Editors::parse_settings()
 * @since 3.3.0
 *
 * @param string $content   Initial content for the editor.
 * @param string $editor_id HTML ID attribute value for the textarea and TinyMCE.
 *                          Should not contain square brackets.
 * @param array  $settings  See _WP_Editors::parse_settings() for description.
 */
function wp_editor( $content, $editor_id, $settings = array() ) {
	if ( ! class_exists( '_WP_Editors', false ) ) {
		require ABSPATH . WPINC . '/class-wp-editor.php';
	}
	_WP_Editors::editor( $content, $editor_id, $settings );
}

/**
 * Outputs the editor scripts, stylesheets, and default settings.
 *
 * The editor can be initialized when needed after page load.
 * See wp.editor.initialize() in wp-admin/js/editor.js for initialization options.
 *
 * @uses _WP_Editors
 * @since 4.8.0
 */
function wp_enqueue_editor() {
	if ( ! class_exists( '_WP_Editors', false ) ) {
		require ABSPATH . WPINC . '/class-wp-editor.php';
	}

	_WP_Editors::enqueue_default_editor();
}

/**
 * Enqueues assets needed by the code editor for the given settings.
 *
 * @since 4.9.0
 *
 * @see wp_enqueue_editor()
 * @see wp_get_code_editor_settings();
 * @see _WP_Editors::parse_settings()
 *
 * @param array $args {
 *     Args.
 *
 *     @type string   $type       The MIME type of the file to be edited.
 *     @type string   $file       Filename to be edited. Extension is used to sniff the type. Can be supplied as alternative to `$type` param.
 *     @type WP_Theme $theme      Theme being edited when on the theme file editor.
 *     @type string   $plugin     Plugin being edited when on the plugin file editor.
 *     @type array    $codemirror Additional CodeMirror setting overrides.
 *     @type array    $csslint    CSSLint rule overrides.
 *     @type array    $jshint     JSHint rule overrides.
 *     @type array    $htmlhint   HTMLHint rule overrides.
 * }
 * @return array|false Settings for the enqueued code editor, or false if the editor was not enqueued.
 */
function wp_enqueue_code_editor( $args ) {
	if ( is_user_logged_in() && 'false' === wp_get_current_user()->syntax_highlighting ) {
		return false;
	}

	$settings = wp_get_code_editor_settings( $args );

	if ( empty( $settings ) || empty( $settings['codemirror'] ) ) {
		return false;
	}

	wp_enqueue_script( 'code-editor' );
	wp_enqueue_style( 'code-editor' );

	if ( isset( $settings['codemirror']['mode'] ) ) {
		$mode = $settings['codemirror']['mode'];
		if ( is_string( $mode ) ) {
			$mode = array(
				'name' => $mode,
			);
		}

		if ( ! empty( $settings['codemirror']['lint'] ) ) {
			switch ( $mode['name'] ) {
				case 'css':
				case 'text/css':
				case 'text/x-scss':
				case 'text/x-less':
					wp_enqueue_script( 'csslint' );
					break;
				case 'htmlmixed':
				case 'text/html':
				case 'php':
				case 'application/x-httpd-php':
				case 'text/x-php':
					wp_enqueue_script( 'htmlhint' );
					wp_enqueue_script( 'csslint' );
					wp_enqueue_script( 'jshint' );
					if ( ! current_user_can( 'unfiltered_html' ) ) {
						wp_enqueue_script( 'htmlhint-kses' );
					}
					break;
				case 'javascript':
				case 'application/ecmascript':
				case 'application/json':
				case 'application/javascript':
				case 'application/ld+json':
				case 'text/typescript':
				case 'application/typescript':
					wp_enqueue_script( 'jshint' );
					wp_enqueue_script( 'jsonlint' );
					break;
			}
		}
	}

	wp_add_inline_script( 'code-editor', sprintf( 'jQuery.extend( wp.codeEditor.defaultSettings, %s );', wp_json_encode( $settings ) ) );

	/**
	 * Fires when scripts and styles are enqueued for the code editor.
	 *
	 * @since 4.9.0
	 *
	 * @param array $settings Settings for the enqueued code editor.
	 */
	do_action( 'wp_enqueue_code_editor', $settings );

	return $settings;
}

/**
 * Generates and returns code editor settings.
 *
 * @since 5.0.0
 *
 * @see wp_enqueue_code_editor()
 *
 * @param array $args {
 *     Args.
 *
 *     @type string   $type       The MIME type of the file to be edited.
 *     @type string   $file       Filename to be edited. Extension is used to sniff the type. Can be supplied as alternative to `$type` param.
 *     @type WP_Theme $theme      Theme being edited when on the theme file editor.
 *     @type string   $plugin     Plugin being edited when on the plugin file editor.
 *     @type array    $codemirror Additional CodeMirror setting overrides.
 *     @type array    $csslint    CSSLint rule overrides.
 *     @type array    $jshint     JSHint rule overrides.
 *     @type array    $htmlhint   HTMLHint rule overrides.
 * }
 * @return array|false Settings for the code editor.
 */
function wp_get_code_editor_settings( $args ) {
	$settings = array(
		'codemirror' => array(
			'indentUnit'       => 4,
			'indentWithTabs'   => true,
			'inputStyle'       => 'contenteditable',
			'lineNumbers'      => true,
			'lineWrapping'     => true,
			'styleActiveLine'  => true,
			'continueComments' => true,
			'extraKeys'        => array(
				'Ctrl-Space' => 'autocomplete',
				'Ctrl-/'     => 'toggleComment',
				'Cmd-/'      => 'toggleComment',
				'Alt-F'      => 'findPersistent',
				'Ctrl-F'     => 'findPersistent',
				'Cmd-F'      => 'findPersistent',
			),
			'direction'        => 'ltr', // Code is shown in LTR even in RTL languages.
			'gutters'          => array(),
		),
		'csslint'    => array(
			'errors'                    => true, // Parsing errors.
			'box-model'                 => true,
			'display-property-grouping' => true,
			'duplicate-properties'      => true,
			'known-properties'          => true,
			'outline-none'              => true,
		),
		'jshint'     => array(
			// The following are copied from <https://github.com/WordPress/wordpress-develop/blob/4.8.1/.jshintrc>.
			'boss'     => true,
			'curly'    => true,
			'eqeqeq'   => true,
			'eqnull'   => true,
			'es3'      => true,
			'expr'     => true,
			'immed'    => true,
			'noarg'    => true,
			'nonbsp'   => true,
			'onevar'   => true,
			'quotmark' => 'single',
			'trailing' => true,
			'undef'    => true,
			'unused'   => true,

			'browser'  => true,

			'globals'  => array(
				'_'        => false,
				'Backbone' => false,
				'jQuery'   => false,
				'JSON'     => false,
				'wp'       => false,
			),
		),
		'htmlhint'   => array(
			'tagname-lowercase'        => true,
			'attr-lowercase'           => true,
			'attr-value-double-quotes' => false,
			'doctype-first'            => false,
			'tag-pair'                 => true,
			'spec-char-escape'         => true,
			'id-unique'                => true,
			'src-not-empty'            => true,
			'attr-no-duplication'      => true,
			'alt-require'              => true,
			'space-tab-mixed-disabled' => 'tab',
			'attr-unsafe-chars'        => true,
		),
	);

	$type = '';
	if ( isset( $args['type'] ) ) {
		$type = $args['type'];

		// Remap MIME types to ones that CodeMirror modes will recognize.
		if ( 'application/x-patch' === $type || 'text/x-patch' === $type ) {
			$type = 'text/x-diff';
		}
	} elseif ( isset( $args['file'] ) && str_contains( basename( $args['file'] ), '.' ) ) {
		$extension = strtolower( pathinfo( $args['file'], PATHINFO_EXTENSION ) );
		foreach ( wp_get_mime_types() as $exts => $mime ) {
			if ( preg_match( '!^(' . $exts . ')$!i', $extension ) ) {
				$type = $mime;
				break;
			}
		}

		// Supply any types that are not matched by wp_get_mime_types().
		if ( empty( $type ) ) {
			switch ( $extension ) {
				case 'conf':
					$type = 'text/nginx';
					break;
				case 'css':
					$type = 'text/css';
					break;
				case 'diff':
				case 'patch':
					$type = 'text/x-diff';
					break;
				case 'html':
				case 'htm':
					$type = 'text/html';
					break;
				case 'http':
					$type = 'message/http';
					break;
				case 'js':
					$type = 'text/javascript';
					break;
				case 'json':
					$type = 'application/json';
					break;
				case 'jsx':
					$type = 'text/jsx';
					break;
				case 'less':
					$type = 'text/x-less';
					break;
				case 'md':
					$type = 'text/x-gfm';
					break;
				case 'php':
				case 'phtml':
				case 'php3':
				case 'php4':
				case 'php5':
				case 'php7':
				case 'phps':
					$type = 'application/x-httpd-php';
					break;
				case 'scss':
					$type = 'text/x-scss';
					break;
				case 'sass':
					$type = 'text/x-sass';
					break;
				case 'sh':
				case 'bash':
					$type = 'text/x-sh';
					break;
				case 'sql':
					$type = 'text/x-sql';
					break;
				case 'svg':
					$type = 'application/svg+xml';
					break;
				case 'xml':
					$type = 'text/xml';
					break;
				case 'yml':
				case 'yaml':
					$type = 'text/x-yaml';
					break;
				case 'txt':
				default:
					$type = 'text/plain';
					break;
			}
		}
	}

	if ( in_array( $type, array( 'text/css', 'text/x-scss', 'text/x-less', 'text/x-sass' ), true ) ) {
		$settings['codemirror'] = array_merge(
			$settings['codemirror'],
			array(
				'mode'              => $type,
				'lint'              => false,
				'autoCloseBrackets' => true,
				'matchBrackets'     => true,
			)
		);
	} elseif ( 'text/x-diff' === $type ) {
		$settings['codemirror'] = array_merge(
			$settings['codemirror'],
			array(
				'mode' => 'diff',
			)
		);
	} elseif ( 'text/html' === $type ) {
		$settings['codemirror'] = array_merge(
			$settings['codemirror'],
			array(
				'mode'              => 'htmlmixed',
				'lint'              => true,
				'autoCloseBrackets' => true,
				'autoCloseTags'     => true,
				'matchTags'         => array(
					'bothTags' => true,
				),
			)
		);

		if ( ! current_user_can( 'unfiltered_html' ) ) {
			$settings['htmlhint']['kses'] = wp_kses_allowed_html( 'post' );
		}
	} elseif ( 'text/x-gfm' === $type ) {
		$settings['codemirror'] = array_merge(
			$settings['codemirror'],
			array(
				'mode'                => 'gfm',
				'highlightFormatting' => true,
			)
		);
	} elseif ( 'application/javascript' === $type || 'text/javascript' === $type ) {
		$settings['codemirror'] = array_merge(
			$settings['codemirror'],
			array(
				'mode'              => 'javascript',
				'lint'              => true,
				'autoCloseBrackets' => true,
				'matchBrackets'     => true,
			)
		);
	} elseif ( str_contains( $type, 'json' ) ) {
		$settings['codemirror'] = array_merge(
			$settings['codemirror'],
			array(
				'mode'              => array(
					'name' => 'javascript',
				),
				'lint'              => true,
				'autoCloseBrackets' => true,
				'matchBrackets'     => true,
			)
		);
		if ( 'application/ld+json' === $type ) {
			$settings['codemirror']['mode']['jsonld'] = true;
		} else {
			$settings['codemirror']['mode']['json'] = true;
		}
	} elseif ( str_contains( $type, 'jsx' ) ) {
		$settings['codemirror'] = array_merge(
			$settings['codemirror'],
			array(
				'mode'              => 'jsx',
				'autoCloseBrackets' => true,
				'matchBrackets'     => true,
			)
		);
	} elseif ( 'text/x-markdown' === $type ) {
		$settings['codemirror'] = array_merge(
			$settings['codemirror'],
			array(
				'mode'                => 'markdown',
				'highlightFormatting' => true,
			)
		);
	} elseif ( 'text/nginx' === $type ) {
		$settings['codemirror'] = array_merge(
			$settings['codemirror'],
			array(
				'mode' => 'nginx',
			)
		);
	} elseif ( 'application/x-httpd-php' === $type ) {
		$settings['codemirror'] = array_merge(
			$settings['codemirror'],
			array(
				'mode'              => 'php',
				'autoCloseBrackets' => true,
				'autoCloseTags'     => true,
				'matchBrackets'     => true,
				'matchTags'         => array(
					'bothTags' => true,
				),
			)
		);
	} elseif ( 'text/x-sql' === $type || 'text/x-mysql' === $type ) {
		$settings['codemirror'] = array_merge(
			$settings['codemirror'],
			array(
				'mode'              => 'sql',
				'autoCloseBrackets' => true,
				'matchBrackets'     => true,
			)
		);
	} elseif ( str_contains( $type, 'xml' ) ) {
		$settings['codemirror'] = array_merge(
			$settings['codemirror'],
			array(
				'mode'              => 'xml',
				'autoCloseBrackets' => true,
				'autoCloseTags'     => true,
				'matchTags'         => array(
					'bothTags' => true,
				),
			)
		);
	} elseif ( 'text/x-yaml' === $type ) {
		$settings['codemirror'] = array_merge(
			$settings['codemirror'],
			array(
				'mode' => 'yaml',
			)
		);
	} else {
		$settings['codemirror']['mode'] = $type;
	}

	if ( ! empty( $settings['codemirror']['lint'] ) ) {
		$settings['codemirror']['gutters'][] = 'CodeMirror-lint-markers';
	}

	// Let settings supplied via args override any defaults.
	foreach ( wp_array_slice_assoc( $args, array( 'codemirror', 'csslint', 'jshint', 'htmlhint' ) ) as $key => $value ) {
		$settings[ $key ] = array_merge(
			$settings[ $key ],
			$value
		);
	}

	/**
	 * Filters settings that are passed into the code editor.
	 *
	 * Returning a falsey value will disable the syntax-highlighting code editor.
	 *
	 * @since 4.9.0
	 *
	 * @param array $settings The array of settings passed to the code editor.
	 *                        A falsey value disables the editor.
	 * @param array $args {
	 *     Args passed when calling `get_code_editor_settings()`.
	 *
	 *     @type string   $type       The MIME type of the file to be edited.
	 *     @type string   $file       Filename being edited.
	 *     @type WP_Theme $theme      Theme being edited when on the theme file editor.
	 *     @type string   $plugin     Plugin being edited when on the plugin file editor.
	 *     @type array    $codemirror Additional CodeMirror setting overrides.
	 *     @type array    $csslint    CSSLint rule overrides.
	 *     @type array    $jshint     JSHint rule overrides.
	 *     @type array    $htmlhint   HTMLHint rule overrides.
	 * }
	 */
	return apply_filters( 'wp_code_editor_settings', $settings, $args );
}

/**
 * Retrieves the contents of the search WordPress query variable.
 *
 * The search query string is passed through esc_attr() to ensure that it is safe
 * for placing in an HTML attribute.
 *
 * @since 2.3.0
 *
 * @param bool $escaped Whether the result is escaped. Default true.
 *                      Only use when you are later escaping it. Do not use unescaped.
 * @return string
 */
function get_search_query( $escaped = true ) {
	/**
	 * Filters the contents of the search query variable.
	 *
	 * @since 2.3.0
	 *
	 * @param mixed $search Contents of the search query variable.
	 */
	$query = apply_filters( 'get_search_query', get_query_var( 's' ) );

	if ( $escaped ) {
		$query = esc_attr( $query );
	}
	return $query;
}

/**
 * Displays the contents of the search query variable.
 *
 * The search query string is passed through esc_attr() to ensure that it is safe
 * for placing in an HTML attribute.
 *
 * @since 2.1.0
 */
function the_search_query() {
	/**
	 * Filters the contents of the search query variable for display.
	 *
	 * @since 2.3.0
	 *
	 * @param mixed $search Contents of the search query variable.
	 */
	echo esc_attr( apply_filters( 'the_search_query', get_search_query( false ) ) );
}

/**
 * Gets the language attributes for the 'html' tag.
 *
 * Builds up a set of HTML attributes containing the text direction and language
 * information for the page.
 *
 * @since 4.3.0
 *
 * @param string $doctype Optional. The type of HTML document. Accepts 'xhtml' or 'html'. Default 'html'.
 * @return string A space-separated list of language attributes.
 */
function get_language_attributes( $doctype = 'html' ) {
	$attributes = array();

	if ( function_exists( 'is_rtl' ) && is_rtl() ) {
		$attributes[] = 'dir="rtl"';
	}

	$lang = get_bloginfo( 'language' );
	if ( $lang ) {
		if ( 'text/html' === get_option( 'html_type' ) || 'html' === $doctype ) {
			$attributes[] = 'lang="' . esc_attr( $lang ) . '"';
		}

		if ( 'text/html' !== get_option( 'html_type' ) || 'xhtml' === $doctype ) {
			$attributes[] = 'xml:lang="' . esc_attr( $lang ) . '"';
		}
	}

	$output = implode( ' ', $attributes );

	/**
	 * Filters the language attributes for display in the 'html' tag.
	 *
	 * @since 2.5.0
	 * @since 4.3.0 Added the `$doctype` parameter.
	 *
	 * @param string $output A space-separated list of language attributes.
	 * @param string $doctype The type of HTML document (xhtml|html).
	 */
	return apply_filters( 'language_attributes', $output, $doctype );
}

/**
 * Displays the language attributes for the 'html' tag.
 *
 * Builds up a set of HTML attributes containing the text direction and language
 * information for the page.
 *
 * @since 2.1.0
 * @since 4.3.0 Converted into a wrapper for get_language_attributes().
 *
 * @param string $doctype Optional. The type of HTML document. Accepts 'xhtml' or 'html'. Default 'html'.
 */
function language_attributes( $doctype = 'html' ) {
	echo get_language_attributes( $doctype );
}

/**
 * Retrieves paginated links for archive post pages.
 *
 * Technically, the function can be used to create paginated link list for any
 * area. The 'base' argument is used to reference the url, which will be used to
 * create the paginated links. The 'format' argument is then used for replacing
 * the page number. It is however, most likely and by default, to be used on the
 * archive post pages.
 *
 * The 'type' argument controls format of the returned value. The default is
 * 'plain', which is just a string with the links separated by a newline
 * character. The other possible values are either 'array' or 'list'. The
 * 'array' value will return an array of the paginated link list to offer full
 * control of display. The 'list' value will place all of the paginated links in
 * an unordered HTML list.
 *
 * The 'total' argument is the total amount of pages and is an integer. The
 * 'current' argument is the current page number and is also an integer.
 *
 * An example of the 'base' argument is "http://example.com/all_posts.php%_%"
 * and the '%_%' is required. The '%_%' will be replaced by the contents of in
 * the 'format' argument. An example for the 'format' argument is "?page=%#%"
 * and the '%#%' is also required. The '%#%' will be replaced with the page
 * number.
 *
 * You can include the previous and next links in the list by setting the
 * 'prev_next' argument to true, which it is by default. You can set the
 * previous text, by using the 'prev_text' argument. You can set the next text
 * by setting the 'next_text' argument.
 *
 * If the 'show_all' argument is set to true, then it will show all of the pages
 * instead of a short list of the pages near the current page. By default, the
 * 'show_all' is set to false and controlled by the 'end_size' and 'mid_size'
 * arguments. The 'end_size' argument is how many numbers on either the start
 * and the end list edges, by default is 1. The 'mid_size' argument is how many
 * numbers to either side of current page, but not including current page.
 *
 * It is possible to add query vars to the link by using the 'add_args' argument
 * and see add_query_arg() for more information.
 *
 * The 'before_page_number' and 'after_page_number' arguments allow users to
 * augment the links themselves. Typically this might be to add context to the
 * numbered links so that screen reader users understand what the links are for.
 * The text strings are added before and after the page number - within the
 * anchor tag.
 *
 * @since 2.1.0
 * @since 4.9.0 Added the `aria_current` argument.
 *
 * @global WP_Query   $wp_query   WordPress Query object.
 * @global WP_Rewrite $wp_rewrite WordPress rewrite component.
 *
 * @param string|array $args {
 *     Optional. Array or string of arguments for generating paginated links for archives.
 *
 *     @type string $base               Base of the paginated url. Default empty.
 *     @type string $format             Format for the pagination structure. Default empty.
 *     @type int    $total              The total amount of pages. Default is the value WP_Query's
 *                                      `max_num_pages` or 1.
 *     @type int    $current            The current page number. Default is 'paged' query var or 1.
 *     @type string $aria_current       The value for the aria-current attribute. Possible values are 'page',
 *                                      'step', 'location', 'date', 'time', 'true', 'false'. Default is 'page'.
 *     @type bool   $show_all           Whether to show all pages. Default false.
 *     @type int    $end_size           How many numbers on either the start and the end list edges.
 *                                      Default 1.
 *     @type int    $mid_size           How many numbers to either side of the current pages. Default 2.
 *     @type bool   $prev_next          Whether to include the previous and next links in the list. Default true.
 *     @type string $prev_text          The previous page text. Default '&laquo; Previous'.
 *     @type string $next_text          The next page text. Default 'Next &raquo;'.
 *     @type string $type               Controls format of the returned value. Possible values are 'plain',
 *                                      'array' and 'list'. Default is 'plain'.
 *     @type array  $add_args           An array of query args to add. Default false.
 *     @type string $add_fragment       A string to append to each link. Default empty.
 *     @type string $before_page_number A string to appear before the page number. Default empty.
 *     @type string $after_page_number  A string to append after the page number. Default empty.
 * }
 * @return string|string[]|void String of page links or array of page links, depending on 'type' argument.
 *                              Void if total number of pages is less than 2.
 */
function paginate_links( $args = '' ) {
	global $wp_query, $wp_rewrite;

	// Setting up default values based on the current URL.
	$pagenum_link = html_entity_decode( get_pagenum_link() );
	$url_parts    = explode( '?', $pagenum_link );

	// Get max pages and current page out of the current query, if available.
	$total   = isset( $wp_query->max_num_pages ) ? $wp_query->max_num_pages : 1;
	$current = get_query_var( 'paged' ) ? (int) get_query_var( 'paged' ) : 1;

	// Append the format placeholder to the base URL.
	$pagenum_link = trailingslashit( $url_parts[0] ) . '%_%';

	// URL base depends on permalink settings.
	$format  = $wp_rewrite->using_index_permalinks() && ! strpos( $pagenum_link, 'index.php' ) ? 'index.php/' : '';
	$format .= $wp_rewrite->using_permalinks() ? user_trailingslashit( $wp_rewrite->pagination_base . '/%#%', 'paged' ) : '?paged=%#%';

	$defaults = array(
		'base'               => $pagenum_link, // http://example.com/all_posts.php%_% : %_% is replaced by format (below).
		'format'             => $format, // ?page=%#% : %#% is replaced by the page number.
		'total'              => $total,
		'current'            => $current,
		'aria_current'       => 'page',
		'show_all'           => false,
		'prev_next'          => true,
		'prev_text'          => __( '&laquo; Previous' ),
		'next_text'          => __( 'Next &raquo;' ),
		'end_size'           => 1,
		'mid_size'           => 2,
		'type'               => 'plain',
		'add_args'           => array(), // Array of query args to add.
		'add_fragment'       => '',
		'before_page_number' => '',
		'after_page_number'  => '',
	);

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

	if ( ! is_array( $args['add_args'] ) ) {
		$args['add_args'] = array();
	}

	// Merge additional query vars found in the original URL into 'add_args' array.
	if ( isset( $url_parts[1] ) ) {
		// Find the format argument.
		$format       = explode( '?', str_replace( '%_%', $args['format'], $args['base'] ) );
		$format_query = isset( $format[1] ) ? $format[1] : '';
		wp_parse_str( $format_query, $format_args );

		// Find the query args of the requested URL.
		wp_parse_str( $url_parts[1], $url_query_args );

		// Remove the format argument from the array of query arguments, to avoid overwriting custom format.
		foreach ( $format_args as $format_arg => $format_arg_value ) {
			unset( $url_query_args[ $format_arg ] );
		}

		$args['add_args'] = array_merge( $args['add_args'], urlencode_deep( $url_query_args ) );
	}

	// Who knows what else people pass in $args.
	$total = (int) $args['total'];
	if ( $total < 2 ) {
		return;
	}
	$current  = (int) $args['current'];
	$end_size = (int) $args['end_size']; // Out of bounds? Make it the default.
	if ( $end_size < 1 ) {
		$end_size = 1;
	}
	$mid_size = (int) $args['mid_size'];
	if ( $mid_size < 0 ) {
		$mid_size = 2;
	}

	$add_args   = $args['add_args'];
	$r          = '';
	$page_links = array();
	$dots       = false;

	if ( $args['prev_next'] && $current && 1 < $current ) :
		$link = str_replace( '%_%', 2 == $current ? '' : $args['format'], $args['base'] );
		$link = str_replace( '%#%', $current - 1, $link );
		if ( $add_args ) {
			$link = add_query_arg( $add_args, $link );
		}
		$link .= $args['add_fragment'];

		$page_links[] = sprintf(
			'<a class="prev page-numbers" href="%s">%s</a>',
			/**
			 * Filters the paginated links for the given archive pages.
			 *
			 * @since 3.0.0
			 *
			 * @param string $link The paginated link URL.
			 */
			esc_url( apply_filters( 'paginate_links', $link ) ),
			$args['prev_text']
		);
	endif;

	for ( $n = 1; $n <= $total; $n++ ) :
		if ( $n == $current ) :
			$page_links[] = sprintf(
				'<span aria-current="%s" class="page-numbers current">%s</span>',
				esc_attr( $args['aria_current'] ),
				$args['before_page_number'] . number_format_i18n( $n ) . $args['after_page_number']
			);

			$dots = true;
		else :
			if ( $args['show_all'] || ( $n <= $end_size || ( $current && $n >= $current - $mid_size && $n <= $current + $mid_size ) || $n > $total - $end_size ) ) :
				$link = str_replace( '%_%', 1 == $n ? '' : $args['format'], $args['base'] );
				$link = str_replace( '%#%', $n, $link );
				if ( $add_args ) {
					$link = add_query_arg( $add_args, $link );
				}
				$link .= $args['add_fragment'];

				$page_links[] = sprintf(
					'<a class="page-numbers" href="%s">%s</a>',
					/** This filter is documented in wp-includes/general-template.php */
					esc_url( apply_filters( 'paginate_links', $link ) ),
					$args['before_page_number'] . number_format_i18n( $n ) . $args['after_page_number']
				);

				$dots = true;
			elseif ( $dots && ! $args['show_all'] ) :
				$page_links[] = '<span class="page-numbers dots">' . __( '&hellip;' ) . '</span>';

				$dots = false;
			endif;
		endif;
	endfor;

	if ( $args['prev_next'] && $current && $current < $total ) :
		$link = str_replace( '%_%', $args['format'], $args['base'] );
		$link = str_replace( '%#%', $current + 1, $link );
		if ( $add_args ) {
			$link = add_query_arg( $add_args, $link );
		}
		$link .= $args['add_fragment'];

		$page_links[] = sprintf(
			'<a class="next page-numbers" href="%s">%s</a>',
			/** This filter is documented in wp-includes/general-template.php */
			esc_url( apply_filters( 'paginate_links', $link ) ),
			$args['next_text']
		);
	endif;

	switch ( $args['type'] ) {
		case 'array':
			return $page_links;

		case 'list':
			$r .= "<ul class='page-numbers'>\n\t<li>";
			$r .= implode( "</li>\n\t<li>", $page_links );
			$r .= "</li>\n</ul>\n";
			break;

		default:
			$r = implode( "\n", $page_links );
			break;
	}

	/**
	 * Filters the HTML output of paginated links for archives.
	 *
	 * @since 5.7.0
	 *
	 * @param string $r    HTML output.
	 * @param array  $args An array of arguments. See paginate_links()
	 *                     for information on accepted arguments.
	 */
	$r = apply_filters( 'paginate_links_output', $r, $args );

	return $r;
}

/**
 * Registers an admin color scheme css file.
 *
 * Allows a plugin to register a new admin color scheme. For example:
 *
 *     wp_admin_css_color( 'classic', __( 'Classic' ), admin_url( "css/colors-classic.css" ), array(
 *         '#07273E', '#14568A', '#D54E21', '#2683AE'
 *     ) );
 *
 * @since 2.5.0
 *
 * @global array $_wp_admin_css_colors
 *
 * @param string $key    The unique key for this theme.
 * @param string $name   The name of the theme.
 * @param string $url    The URL of the CSS file containing the color scheme.
 * @param array  $colors Optional. An array of CSS color definition strings which are used
 *                       to give the user a feel for the theme.
 * @param array  $icons {
 *     Optional. CSS color definitions used to color any SVG icons.
 *
 *     @type string $base    SVG icon base color.
 *     @type string $focus   SVG icon color on focus.
 *     @type string $current SVG icon color of current admin menu link.
 * }
 */
function wp_admin_css_color( $key, $name, $url, $colors = array(), $icons = array() ) {
	global $_wp_admin_css_colors;

	if ( ! isset( $_wp_admin_css_colors ) ) {
		$_wp_admin_css_colors = array();
	}

	$_wp_admin_css_colors[ $key ] = (object) array(
		'name'        => $name,
		'url'         => $url,
		'colors'      => $colors,
		'icon_colors' => $icons,
	);
}

/**
 * Registers the default admin color schemes.
 *
 * Registers the initial set of eight color schemes in the Profile section
 * of the dashboard which allows for styling the admin menu and toolbar.
 *
 * @see wp_admin_css_color()
 *
 * @since 3.0.0
 */
function register_admin_color_schemes() {
	$suffix  = is_rtl() ? '-rtl' : '';
	$suffix .= SCRIPT_DEBUG ? '' : '.min';

	wp_admin_css_color(
		'fresh',
		_x( 'Default', 'admin color scheme' ),
		false,
		array( '#1d2327', '#2c3338', '#2271b1', '#72aee6' ),
		array(
			'base'    => '#a7aaad',
			'focus'   => '#72aee6',
			'current' => '#fff',
		)
	);

	wp_admin_css_color(
		'light',
		_x( 'Light', 'admin color scheme' ),
		admin_url( "css/colors/light/colors$suffix.css" ),
		array( '#e5e5e5', '#999', '#d64e07', '#04a4cc' ),
		array(
			'base'    => '#999',
			'focus'   => '#ccc',
			'current' => '#ccc',
		)
	);

	wp_admin_css_color(
		'modern',
		_x( 'Modern', 'admin color scheme' ),
		admin_url( "css/colors/modern/colors$suffix.css" ),
		array( '#1e1e1e', '#3858e9', '#33f078' ),
		array(
			'base'    => '#f3f1f1',
			'focus'   => '#fff',
			'current' => '#fff',
		)
	);

	wp_admin_css_color(
		'blue',
		_x( 'Blue', 'admin color scheme' ),
		admin_url( "css/colors/blue/colors$suffix.css" ),
		array( '#096484', '#4796b3', '#52accc', '#74B6CE' ),
		array(
			'base'    => '#e5f8ff',
			'focus'   => '#fff',
			'current' => '#fff',
		)
	);

	wp_admin_css_color(
		'midnight',
		_x( 'Midnight', 'admin color scheme' ),
		admin_url( "css/colors/midnight/colors$suffix.css" ),
		array( '#25282b', '#363b3f', '#69a8bb', '#e14d43' ),
		array(
			'base'    => '#f1f2f3',
			'focus'   => '#fff',
			'current' => '#fff',
		)
	);

	wp_admin_css_color(
		'sunrise',
		_x( 'Sunrise', 'admin color scheme' ),
		admin_url( "css/colors/sunrise/colors$suffix.css" ),
		array( '#b43c38', '#cf4944', '#dd823b', '#ccaf0b' ),
		array(
			'base'    => '#f3f1f1',
			'focus'   => '#fff',
			'current' => '#fff',
		)
	);

	wp_admin_css_color(
		'ectoplasm',
		_x( 'Ectoplasm', 'admin color scheme' ),
		admin_url( "css/colors/ectoplasm/colors$suffix.css" ),
		array( '#413256', '#523f6d', '#a3b745', '#d46f15' ),
		array(
			'base'    => '#ece6f6',
			'focus'   => '#fff',
			'current' => '#fff',
		)
	);

	wp_admin_css_color(
		'ocean',
		_x( 'Ocean', 'admin color scheme' ),
		admin_url( "css/colors/ocean/colors$suffix.css" ),
		array( '#627c83', '#738e96', '#9ebaa0', '#aa9d88' ),
		array(
			'base'    => '#f2fcff',
			'focus'   => '#fff',
			'current' => '#fff',
		)
	);

	wp_admin_css_color(
		'coffee',
		_x( 'Coffee', 'admin color scheme' ),
		admin_url( "css/colors/coffee/colors$suffix.css" ),
		array( '#46403c', '#59524c', '#c7a589', '#9ea476' ),
		array(
			'base'    => '#f3f2f1',
			'focus'   => '#fff',
			'current' => '#fff',
		)
	);
}

/**
 * Displays the URL of a WordPress admin CSS file.
 *
 * @see WP_Styles::_css_href() and its {@see 'style_loader_src'} filter.
 *
 * @since 2.3.0
 *
 * @param string $file file relative to wp-admin/ without its ".css" extension.
 * @return string
 */
function wp_admin_css_uri( $file = 'wp-admin' ) {
	if ( defined( 'WP_INSTALLING' ) ) {
		$_file = "./$file.css";
	} else {
		$_file = admin_url( "$file.css" );
	}
	$_file = add_query_arg( 'version', get_bloginfo( 'version' ), $_file );

	/**
	 * Filters the URI of a WordPress admin CSS file.
	 *
	 * @since 2.3.0
	 *
	 * @param string $_file Relative path to the file with query arguments attached.
	 * @param string $file  Relative path to the file, minus its ".css" extension.
	 */
	return apply_filters( 'wp_admin_css_uri', $_file, $file );
}

/**
 * Enqueues or directly prints a stylesheet link to the specified CSS file.
 *
 * "Intelligently" decides to enqueue or to print the CSS file. If the
 * {@see 'wp_print_styles'} action has *not* yet been called, the CSS file will be
 * enqueued. If the {@see 'wp_print_styles'} action has been called, the CSS link will
 * be printed. Printing may be forced by passing true as the $force_echo
 * (second) parameter.
 *
 * For backward compatibility with WordPress 2.3 calling method: If the $file
 * (first) parameter does not correspond to a registered CSS file, we assume
 * $file is a file relative to wp-admin/ without its ".css" extension. A
 * stylesheet link to that generated URL is printed.
 *
 * @since 2.3.0
 *
 * @param string $file       Optional. Style handle name or file name (without ".css" extension) relative
 *                           to wp-admin/. Defaults to 'wp-admin'.
 * @param bool   $force_echo Optional. Force the stylesheet link to be printed rather than enqueued.
 */
function wp_admin_css( $file = 'wp-admin', $force_echo = false ) {
	// For backward compatibility.
	$handle = str_starts_with( $file, 'css/' ) ? substr( $file, 4 ) : $file;

	if ( wp_styles()->query( $handle ) ) {
		if ( $force_echo || did_action( 'wp_print_styles' ) ) {
			// We already printed the style queue. Print this one immediately.
			wp_print_styles( $handle );
		} else {
			// Add to style queue.
			wp_enqueue_style( $handle );
		}
		return;
	}

	$stylesheet_link = sprintf(
		"<link rel='stylesheet' href='%s' type='text/css' />\n",
		esc_url( wp_admin_css_uri( $file ) )
	);

	/**
	 * Filters the stylesheet link to the specified CSS file.
	 *
	 * If the site is set to display right-to-left, the RTL stylesheet link
	 * will be used instead.
	 *
	 * @since 2.3.0
	 * @param string $stylesheet_link HTML link element for the stylesheet.
	 * @param string $file            Style handle name or filename (without ".css" extension)
	 *                                relative to wp-admin/. Defaults to 'wp-admin'.
	 */
	echo apply_filters( 'wp_admin_css', $stylesheet_link, $file );

	if ( function_exists( 'is_rtl' ) && is_rtl() ) {
		$rtl_stylesheet_link = sprintf(
			"<link rel='stylesheet' href='%s' type='text/css' />\n",
			esc_url( wp_admin_css_uri( "$file-rtl" ) )
		);

		/** This filter is documented in wp-includes/general-template.php */
		echo apply_filters( 'wp_admin_css', $rtl_stylesheet_link, "$file-rtl" );
	}
}

/**
 * Enqueues the default ThickBox js and css.
 *
 * If any of the settings need to be changed, this can be done with another js
 * file similar to media-upload.js. That file should
 * require array('thickbox') to ensure it is loaded after.
 *
 * @since 2.5.0
 */
function add_thickbox() {
	wp_enqueue_script( 'thickbox' );
	wp_enqueue_style( 'thickbox' );

	if ( is_network_admin() ) {
		add_action( 'admin_head', '_thickbox_path_admin_subfolder' );
	}
}

/**
 * Displays the XHTML generator that is generated on the wp_head hook.
 *
 * See {@see 'wp_head'}.
 *
 * @since 2.5.0
 */
function wp_generator() {
	/**
	 * Filters the output of the XHTML generator tag.
	 *
	 * @since 2.5.0
	 *
	 * @param string $generator_type The XHTML generator.
	 */
	the_generator( apply_filters( 'wp_generator_type', 'xhtml' ) );
}

/**
 * Displays the generator XML or Comment for RSS, ATOM, etc.
 *
 * Returns the correct generator type for the requested output format. Allows
 * for a plugin to filter generators overall the {@see 'the_generator'} filter.
 *
 * @since 2.5.0
 *
 * @param string $type The type of generator to output - (html|xhtml|atom|rss2|rdf|comment|export).
 */
function the_generator( $type ) {
	/**
	 * Filters the output of the XHTML generator tag for display.
	 *
	 * @since 2.5.0
	 *
	 * @param string $generator_type The generator output.
	 * @param string $type           The type of generator to output. Accepts 'html',
	 *                               'xhtml', 'atom', 'rss2', 'rdf', 'comment', 'export'.
	 */
	echo apply_filters( 'the_generator', get_the_generator( $type ), $type ) . "\n";
}

/**
 * Creates the generator XML or Comment for RSS, ATOM, etc.
 *
 * Returns the correct generator type for the requested output format. Allows
 * for a plugin to filter generators on an individual basis using the
 * {@see 'get_the_generator_$type'} filter.
 *
 * @since 2.5.0
 *
 * @param string $type The type of generator to return - (html|xhtml|atom|rss2|rdf|comment|export).
 * @return string|void The HTML content for the generator.
 */
function get_the_generator( $type = '' ) {
	if ( empty( $type ) ) {

		$current_filter = current_filter();
		if ( empty( $current_filter ) ) {
			return;
		}

		switch ( $current_filter ) {
			case 'rss2_head':
			case 'commentsrss2_head':
				$type = 'rss2';
				break;
			case 'rss_head':
			case 'opml_head':
				$type = 'comment';
				break;
			case 'rdf_header':
				$type = 'rdf';
				break;
			case 'atom_head':
			case 'comments_atom_head':
			case 'app_head':
				$type = 'atom';
				break;
		}
	}

	switch ( $type ) {
		case 'html':
			$gen = '<meta name="generator" content="WordPress ' . esc_attr( get_bloginfo( 'version' ) ) . '">';
			break;
		case 'xhtml':
			$gen = '<meta name="generator" content="WordPress ' . esc_attr( get_bloginfo( 'version' ) ) . '" />';
			break;
		case 'atom':
			$gen = '<generator uri="https://wordpress.org/" version="' . esc_attr( get_bloginfo_rss( 'version' ) ) . '">WordPress</generator>';
			break;
		case 'rss2':
			$gen = '<generator>' . sanitize_url( 'https://wordpress.org/?v=' . get_bloginfo_rss( 'version' ) ) . '</generator>';
			break;
		case 'rdf':
			$gen = '<admin:generatorAgent rdf:resource="' . sanitize_url( 'https://wordpress.org/?v=' . get_bloginfo_rss( 'version' ) ) . '" />';
			break;
		case 'comment':
			$gen = '<!-- generator="WordPress/' . esc_attr( get_bloginfo( 'version' ) ) . '" -->';
			break;
		case 'export':
			$gen = '<!-- generator="WordPress/' . esc_attr( get_bloginfo_rss( 'version' ) ) . '" created="' . gmdate( 'Y-m-d H:i' ) . '" -->';
			break;
	}

	/**
	 * Filters the HTML for the retrieved generator type.
	 *
	 * The dynamic portion of the hook name, `$type`, refers to the generator type.
	 *
	 * Possible hook names include:
	 *
	 *  - `get_the_generator_atom`
	 *  - `get_the_generator_comment`
	 *  - `get_the_generator_export`
	 *  - `get_the_generator_html`
	 *  - `get_the_generator_rdf`
	 *  - `get_the_generator_rss2`
	 *  - `get_the_generator_xhtml`
	 *
	 * @since 2.5.0
	 *
	 * @param string $gen  The HTML markup output to wp_head().
	 * @param string $type The type of generator. Accepts 'html', 'xhtml', 'atom',
	 *                     'rss2', 'rdf', 'comment', 'export'.
	 */
	return apply_filters( "get_the_generator_{$type}", $gen, $type );
}

/**
 * Outputs the HTML checked attribute.
 *
 * Compares the first two arguments and if identical marks as checked.
 *
 * @since 1.0.0
 *
 * @param mixed $checked One of the values to compare.
 * @param mixed $current Optional. The other value to compare if not just true.
 *                       Default true.
 * @param bool  $display Optional. Whether to echo or just return the string.
 *                       Default true.
 * @return string HTML attribute or empty string.
 */
function checked( $checked, $current = true, $display = true ) {
	return __checked_selected_helper( $checked, $current, $display, 'checked' );
}

/**
 * Outputs the HTML selected attribute.
 *
 * Compares the first two arguments and if identical marks as selected.
 *
 * @since 1.0.0
 *
 * @param mixed $selected One of the values to compare.
 * @param mixed $current  Optional. The other value to compare if not just true.
 *                        Default true.
 * @param bool  $display  Optional. Whether to echo or just return the string.
 *                        Default true.
 * @return string HTML attribute or empty string.
 */
function selected( $selected, $current = true, $display = true ) {
	return __checked_selected_helper( $selected, $current, $display, 'selected' );
}

/**
 * Outputs the HTML disabled attribute.
 *
 * Compares the first two arguments and if identical marks as disabled.
 *
 * @since 3.0.0
 *
 * @param mixed $disabled One of the values to compare.
 * @param mixed $current  Optional. The other value to compare if not just true.
 *                        Default true.
 * @param bool  $display  Optional. Whether to echo or just return the string.
 *                        Default true.
 * @return string HTML attribute or empty string.
 */
function disabled( $disabled, $current = true, $display = true ) {
	return __checked_selected_helper( $disabled, $current, $display, 'disabled' );
}

/**
 * Outputs the HTML readonly attribute.
 *
 * Compares the first two arguments and if identical marks as readonly.
 *
 * @since 5.9.0
 *
 * @param mixed $readonly_value One of the values to compare.
 * @param mixed $current        Optional. The other value to compare if not just true.
 *                              Default true.
 * @param bool  $display        Optional. Whether to echo or just return the string.
 *                              Default true.
 * @return string HTML attribute or empty string.
 */
function wp_readonly( $readonly_value, $current = true, $display = true ) {
	return __checked_selected_helper( $readonly_value, $current, $display, 'readonly' );
}

/*
 * Include a compat `readonly()` function on PHP < 8.1. Since PHP 8.1,
 * `readonly` is a reserved keyword and cannot be used as a function name.
 * In order to avoid PHP parser errors, this function was extracted
 * to a separate file and is only included conditionally on PHP < 8.1.
 */
if ( PHP_VERSION_ID < 80100 ) {
	require_once __DIR__ . '/php-compat/readonly.php';
}

/**
 * Private helper function for checked, selected, disabled and readonly.
 *
 * Compares the first two arguments and if identical marks as `$type`.
 *
 * @since 2.8.0
 * @access private
 *
 * @param mixed  $helper  One of the values to compare.
 * @param mixed  $current The other value to compare if not just true.
 * @param bool   $display Whether to echo or just return the string.
 * @param string $type    The type of checked|selected|disabled|readonly we are doing.
 * @return string HTML attribute or empty string.
 */
function __checked_selected_helper( $helper, $current, $display, $type ) { // phpcs:ignore WordPress.NamingConventions.ValidFunctionName.FunctionDoubleUnderscore,PHPCompatibility.FunctionNameRestrictions.ReservedFunctionNames.FunctionDoubleUnderscore
	if ( (string) $helper === (string) $current ) {
		$result = " $type='$type'";
	} else {
		$result = '';
	}

	if ( $display ) {
		echo $result;
	}

	return $result;
}

/**
 * Assigns a visual indicator for required form fields.
 *
 * @since 6.1.0
 *
 * @return string Indicator glyph wrapped in a `span` tag.
 */
function wp_required_field_indicator() {
	/* translators: Character to identify required form fields. */
	$glyph     = __( '*' );
	$indicator = '<span class="required">' . esc_html( $glyph ) . '</span>';

	/**
	 * Filters the markup for a visual indicator of required form fields.
	 *
	 * @since 6.1.0
	 *
	 * @param string $indicator Markup for the indicator element.
	 */
	return apply_filters( 'wp_required_field_indicator', $indicator );
}

/**
 * Creates a message to explain required form fields.
 *
 * @since 6.1.0
 *
 * @return string Message text and glyph wrapped in a `span` tag.
 */
function wp_required_field_message() {
	$message = sprintf(
		'<span class="required-field-message">%s</span>',
		/* translators: %s: Asterisk symbol (*). */
		sprintf( __( 'Required fields are marked %s' ), wp_required_field_indicator() )
	);

	/**
	 * Filters the message to explain required form fields.
	 *
	 * @since 6.1.0
	 *
	 * @param string $message Message text and glyph wrapped in a `span` tag.
	 */
	return apply_filters( 'wp_required_field_message', $message );
}

/**
 * Default settings for heartbeat.
 *
 * Outputs the nonce used in the heartbeat XHR.
 *
 * @since 3.6.0
 *
 * @param array $settings
 * @return array Heartbeat settings.
 */
function wp_heartbeat_settings( $settings ) {
	if ( ! is_admin() ) {
		$settings['ajaxurl'] = admin_url( 'admin-ajax.php', 'relative' );
	}

	if ( is_user_logged_in() ) {
		$settings['nonce'] = wp_create_nonce( 'heartbeat-nonce' );
	}

	return $settings;
}