Useful Theme Functions

custom_pagination($query = null, $range = 2) Displays a custom, numbered pagination for posts or custom queries. It shows the current page, a range of neighbor pages, and links to the first and last pages with ellipses (...) where pages are skipped. Parameters: $query (WP_Query Object, optional) - The WP_Query object to paginate. Defaults to the global $wp_query.
$range (Int, optional) - The number of page links to show on either side of the current page. Default is 2. Returns: Void - Echos the HTML for the pagination navigation directly to the output.

is_mobile() Detects if the user agent string indicates a request is coming from a common mobile phone or small-screen device (e.g., Android, iPhone, Blackberry, etc.). Returns: Boolean - true if the user agent matches common mobile patterns, otherwise false.

is_curl_installed() Checks if the cURL PHP extension is installed and loaded on the server. cURL is often required for making outgoing HTTP requests (e.g., to APIs). Returns: Boolean - true if cURL is installed and enabled, otherwise false.

get_current_language_slug() Retrieves the current two-character language slug (e.g., "en", "de"). It supports Polylang and WPML, falling back to the site's default locale if no language plugin is active. Returns: String - The current language slug.

string_to_slug($str) Converts a given string (like a title) into a URL-friendly, lowercase slug. It specifically handles German umlauts (ä, ö, ü, ß) by converting them to their two-letter equivalents (ae, oe, ue, sz). Parameters: $str (String) - The input string to convert. Returns: String - The converted, clean slug (e.g., 'meine-neue-post').

tel_to_link($phone_number, $vorwahl = '43') Standardizes a phone number, regardless of its messy input format (spaces, dashes, parentheses), into a clean `+COUNTRYCODE` format suitable for `tel:` links. It strips all non-numeric and non-plus characters. Parameters: $phone_number (String) - The phone number to format (e.g., `+43 (0) 316-123`).
$vorwahl (String, optional) - The default country code (without '+') to use if the number is provided in a local format (e.g., starting with '0'). Default is '43'. Returns: String - The formatted phone number (e.g., '+433161234567').

get_attachment($attachment_id) A wrapper function to easily retrieve common metadata for a WordPress media attachment by its ID, compiling them into a single associative array. Parameters: $attachment_id (Int) - The ID of the media file/attachment. Returns: Array - Contains attachment details: `url`, `title`, `caption`, `description`, `alt` text, and `filename`.

get_registered_image_sizes() Fetches a list of all default WordPress image sizes and any custom image sizes registered by the theme or plugins. Useful for options/settings pages. Returns: Array - An associative array where keys are image size slugs (e.g., 'thumbnail', 'custom_size') and values are user-friendly descriptions (e.g., 'Thumbnail - 150 x 150 (crop)'). Includes 'full' size.

get_social_media_icon($platform, $attrs = array()) Renders the SVG icon for a specified social media platform. It first checks for a theme template (`templates/svg/social-platform.php`) and falls back to a generic circle icon if a specific template is not found. Parameters: $platform (String) - The name of the social media platform (e.g., 'facebook', 'instagram').
$attrs (Array, optional) - An array of HTML attributes (e.g., `['width' => '32', 'class' => 'my-icon']`) to apply to the SVG element. Returns: String - The HTML markup for the SVG icon.

nl2span($string, $class = '') Converts newlines in a string into HTML span tags, wrapping each non-empty line of text. This is commonly used for CSS-based animations or complex text styling where each line needs to be treated as a separate element. Parameters: $string (String) - The input string containing newlines.
$class (String, optional) - An optional CSS class to apply to all wrapping <span> tags. Returns: String - The string with each non-empty line wrapped in a <span> tag.