How to filter a taxonomy meta field to the 'single_term_title' filter hook

Question

To show terms in Bengali I enabled term meta fields, saving data into options table. I made a custom function (get_term_meta()) similar to post_meta to fetch my taxonomy meta data, that takes term_id and the term_meta_key as parameters. How can I use a function so that I can filter my default term titles with the term meta I defined. I tried:

function bn_term_title() {
    var_dump($term);
    /*if( get_locale() === 'bn_BD' )
        return get_term_meta( $term->term_id, 'term_bn' );*/
}
add_filter( 'single_term_title', 'bn_term_title' );

But var_dump( $term ); returns null. How can I get the term_id inside the function?

P.S.: get_term_meta() acts like: get_option( "option_key_name{$term_id}" );

Answer 1

Solved the issue by passing the term_name as a parameter to the callback function to the filter.

function bn_term_title( $term_name ) {
    $term_types = get_term_by( 'name', $term_name, 'tax_1' );
    if( $term_types->taxonomy === 'tax_1' ) {
        if( get_locale() === 'bn_BD' )
            return get_term_meta( $term_types->term_id, 'tax1_bn' );
        else
            return $term_name;
    }

    $term_categories = get_term_by( 'name', $term_name, 'tax_2' );
    if( $term_categories->taxonomy === 'tax_2' ) {
        if( get_locale() === 'bn_BD' )
            return get_term_meta( $term_categories->term_id, 'tax2_bn' );
        else
            return $term_name;
    }
}
add_filter( 'single_term_title', 'bn_term_title' );

The code can be more concise when get_term_by() will make the $taxonomy parameter optional. If the taxonomy parameter become optional we can do it like below:

function bn_term_title( $term_name ) {
    $term_types = get_term_by( 'name', $term_name );
    if( get_locale() === 'bn_BD' )
        return get_term_meta( $term_types->term_id, 'term_bn' );
    else
        return $term_name;
}
add_filter( 'single_term_title', 'bn_term_title' );