Improved Text Cutter (ProcessWire Hook)

$wire->addHook('Page::summarize', function($event) {
    $fieldName = $event->arguments(0);
    if(!$fieldName) throw new WireException("No field provided");

    // get max length or use 300 as default if none provided
    $maxLength = (int) $event->arguments(1);
    if(!$maxLength) $maxLength = 300;

    $ending = $event->arguments(2);
    if(!$ending) $ending = '…';

    $ending = html_entity_decode($ending);

    if($maxLength <= 0) {
        throw new WireException("The max length cannot be less than or equal to the length of the appended ending");
    }

    $page = $event->object;
    $value = strip_tags(html_entity_decode((string) $page->get($fieldName)));

    if(mb_strlen($value) > $maxLength) {
        $event->return = $value;

        // Subtract length of decoded ending from the maxLength, as this function
        // should return a string no longer than $maxLength, and the ending should
        // be included within that.
        $maxLength -= mb_strlen($ending);

        // Don't cut on a non-alphabetic char
        while(!ctype_alpha($value[$maxLength-1])) {
            $maxLength--;
            if($maxLength <= 0) break;
        }

        $value = mb_substr($value, 0, $maxLength);

        $value .= $ending;
    }

    // if output formatting on, make sure value is entity encoded
    if($page->of()) $value = $event->sanitizer->entities1($value);

    $event->return = $value;
});