Infinite next and previous post looping but in same term in WordPress

infinite-previous-next-same-term-looping.php

<?php 
/**
 *  Infinite next and previous post looping in WordPress
 *  
 *  This will stay in same Custom Taxonomy Term. Also NEXT and PREVIOUS
 *  are switched to give the impression of "Going Forard and Back"
 */
if( get_adjacent_post(true, '', false, 'CUSTOM_TAX') ) { 

	 next_post_link( '%link', 'PREVIOUS', TRUE, ' ', 'CUSTOM_TAX' ); 

 } else { 
	$args = array(
		'post_type'=>'CUSTOM_POST_TYPE',
		'posts_per_page' => 1, 
		'order' => 'ASC',
		'tax_query' => array(
			array(
				'taxonomy' => 'CUSTOM_TAX', // your custom taxonomy
				'field' => 'slug',
				'terms' => array( 'term' ) // the terms (categories) you created
			)
		)
	);

    $first = new WP_Query($args); 
    $first->the_post(); 

     echo '<a href="' . get_permalink() . '">PREVIOUS</a>'; 

      wp_reset_query();
}; 

if( get_adjacent_post(true, '', true, 'CUSTOM_TAX') ) { 

	 previous_post_link( '%link', 'NEXT', TRUE, ' ', 'CUSTOM_TAX' ); 

 } else { 
	$args = array(
		'post_type'=>'CUSTOM_POST_TYPE',
		'posts_per_page' => 1, 
		'order' => 'DESC',
		'tax_query' => array(
			array(
				'taxonomy' => 'CUSTOM_TAX', // your custom taxonomy
				'field' => 'slug',
				'terms' => array( 'term' ) // the terms (categories) you created
			)
		)
	);

    $first = new WP_Query($args); 
    $first->the_post(); 

     echo '<a href="' . get_permalink() . '">NEXT</a>'; 

      wp_reset_query();
};