Assign folder to an uploaded attachment with Wicked Folders using PHP

wicked-folder-set-folder-attachment_upload.php

<?php

/**
 * Adds an object to the given folder name.
 * 
 * @param $object_id
 * @param $folder_name
 * @param $parent_folder_id
 *                         
 * @return bool
 */
function rs_assign_folder_to_object( $object_id, $folder_name, $parent_folder_id = 0 ) {
	$term_name = $folder_name;
	$taxonomy = 'wf_'. get_post_type( $object_id ) .'_folders';
	
	// Get the existing term name
	$term_id = term_exists( $term_name, $taxonomy, $parent_folder_id );
	
	if ( !$term_id ) {
		// Create the term instead
		$t = wp_insert_term( $term_name, $taxonomy, array( 'parent' => $parent_folder_id ) );
		
		if ( $t && !is_wp_error($t) ) $term_id = $t['term_id'];
	}
	
	if ( $term_id ) {
		wp_add_object_terms( $object_id, $term_id, 'wf_attachment_folders' );
	}
	
	return false;
}



// *******************
// EXAMPLE USAGE
// *******************

// Assign attachment ID #47 to the folder "Important Documents"
function example_assign_folder_to_attachment() {
    $attachment_id = 47;
    $folder_name = 'Important Documents';
    
    rs_assign_folder_to_object( $attachment_id, $folder_name );
}

// MUST be called after "init" priority 15, which is where the taxonomy is registered.
// If you call this function earlier the example will not work.
add_action( 'init', 'example_assign_folder_to_attachment', 16 );