*/
private static $notes = array();
/**
* Running group number, one per content with footnotes.
*
* @var int
*/
private static $group = 0;
/**
* Hooks: the list is added after do_shortcode, before the table of contents (12) reads the headings.
* Same priority as do_shortcode (11); core adds that one first, so it runs before ours.
*/
public static function init(): void {
add_filter( 'the_content', array( __CLASS__, 'start' ), 1 );
add_filter( 'the_content', array( __CLASS__, 'append_list' ), 11 );
}
/**
* Every content starts its own numbering.
*
* @param mixed $content Post content.
* @return mixed
*/
public static function start( $content ) {
self::$notes = array();
return $content;
}
/**
* [threece_fn]: the raised number linking to its entry.
*
* @param string $content Footnote text.
* @param string $classes Extra CSS classes.
* @return string
*/
public static function reference( $content, $classes ) {
$text = trim( (string) preg_replace( '##', ' ', do_shortcode( (string) $content ) ) );
if ( '' === trim( wp_strip_all_tags( $text ) ) ) {
return '';
}
if ( empty( self::$notes ) ) {
++self::$group;
}
self::$notes[] = $text;
$number = count( self::$notes );
wp_enqueue_style( 'threece-elements' );
return sprintf(
'%5$d',
esc_attr( trim( 'threece-fn ' . $classes ) ),
esc_attr( self::id( 'threece-fn', $number ) ),
esc_attr( self::id( 'threece-fnref', $number ) ),
/* translators: %d: footnote number */
esc_attr( sprintf( __( 'Footnote %d', '3task-toolbar-for-classic-editor' ), $number ) ),
$number
);
}
/**
* Adds the list of the collected footnotes to the end of the content.
*
* @param mixed $content Post content after do_shortcode.
* @return mixed
*/
public static function append_list( $content ) {
if ( ! is_string( $content ) || empty( self::$notes ) ) {
return $content;
}
$items = '';
foreach ( self::$notes as $index => $text ) {
$number = $index + 1;
$items .= sprintf(
'%2$s ',
esc_attr( self::id( 'threece-fn', $number ) ),
wp_kses_post( $text ),
esc_attr( self::id( 'threece-fnref', $number ) ),
/* translators: %d: footnote number */
esc_attr( sprintf( __( 'Back to reference %d', '3task-toolbar-for-classic-editor' ), $number ) )
);
}
self::$notes = array();
return $content . "\n" . '';
}
/**
* ID of a footnote or its reference.
*
* @param string $prefix threece-fn or threece-fnref.
* @param int $number Footnote number.
* @return string
*/
private static function id( $prefix, $number ) {
return $prefix . '-' . self::$group . '-' . $number;
}
}