Weighted Tag Feature

Hi again

This is a very specific use case that can be done with the filters provided by this plugin.
The related posts get a score of how many terms they have in common.

If I understand correctly
keywords, actors and directors and genre are taxonomies.
Related posts with genre terms assigned should have a lesser score, or do all posts have the genre terms assigned?

https://keesiemeijer.wordpress.com/related-posts-by-taxonomy/filters/

I understand, let me see what I can do.

Is this for the widget only? Or should this apply to the shortcode also?

Try it with this in your (child) theme’s functions.php file.

// return all related posts (with the widget) for re-ordering of posts by weight
add_filter( 'related_posts_by_taxonomy_widget_args', 'rpbt_return_all_related_posts' );

function rpbt_return_all_related_posts( $args ) {

	// store posts_per_page in a temp variable
	$args['_posts_per_page'] = $args['posts_per_page'];

	// set posts_per_page to return all posts for re-ordering
	$args['posts_per_page']  = -1;

	return $args;
}

// re-orders related posts by weight
add_filter( 'related_posts_by_taxonomy', 'rpbt_reorder_posts_by_weght', 10, 4 );

function rpbt_reorder_posts_by_weght( $results, $post_id, $taxonomies, $args ) {

	// Edit these genre terms ids to your genre term ids
	$genre_term_ids = array( 12, 13, 40, 41, 56 );

	// Check if it's related posts for the the widget
	// The widget returns all related posts
	if ( 'widget' !== $args['type'] ) {
		return $results;
	}

	foreach ( $results as $key => $value ) {

		if ( !isset( $value->related_terms ) || !isset( $value->score ) ) {
			continue;
		}

		// get terms assigned to this related post
		$terms = explode( ',', $value->related_terms );

		foreach ( $terms as $term ) {

			// check if the post term is a genre term
			if ( in_array( $term, $genre_term_ids ) ) {

				// reduce related post score with 0.5
				$results[ $key ]->score[0] = $results[ $key ]->score[0] - 0.5;
			}
		}
	}

	// re-order related posts with new scores
	uasort(  $results, 'km_rpbt_related_posts_by_taxonomy_cmp' );

	// use original posts_per_page from the widget
	if ( isset( $args['_posts_per_page'] ) ) {
		$results = array_slice( $results, 0, absint( $args['_posts_per_page'] ) );
	}

	return $results;
}

// Adds the terms assigned to related posts to the results
add_filter( 'related_posts_by_taxonomy_posts_clauses', 'rpbt_add_terms_to_results', 10, 4 );

function rpbt_add_terms_to_results( $pieces, $post_id, $taxonomies, $args ) {
	global $wpdb;

	$pieces['select_sql'] .= " , GROUP_CONCAT( DISTINCT tt.term_id SEPARATOR ',' ) as related_terms ";

	return $pieces;
}

Change the genre term IDs in this line to your genre term ids.

$genre_term_ids = array( 12, 13, 40, 41, 56 );

btw:
consider creating a child theme instead of editing your theme directly – if you upgrade the theme all your modifications will be lost. Or create a plugin with the code above.

Please check if the tag ids are correct by using this method

Go to Posts > Tags and click on the tag name. The edit tag page will open and you will then be able to see the tag ID by looking onto your browser’s address bar. You will notice a URL similar to this:

yoursite.com/wp-admin/edit-tags.php?action=edit&taxonomy=post_tag&tag_ID=68&post_type=post

The number in tag_ID=68 is the id of the tag.

There are also plugins that show the ID.
https://wordpress.org/plugins/reveal-ids-for-wp-admin-25/

How did it fail. Were the post not ordered as it should or did something else go wrong