wcfad_role_pricing_rules.php

<?php
/**
 * Filter global role-based discounts
 */
function prefix_role_pricing_rules( $rules, $product=false ) {
	
	if( ! $product ) {
		return $rules;
	}
	
	// List your discounts here
	// List each brand ID with an array of roles and their adjusted discounts
	$discounts_by_brand = array(
		'32'	=> array(
			'administrator'	=> 12,
			'editor'		=> 15
		),
		'33'	=> array(
			'administrator'	=> 12,
			'editor'		=> 18
		),
	);
	
	// Check what the user role is
	$roles = wcfad_get_current_user_roles();
	if( ! $roles ) {
		return $rules;
	}
	
	// Check what brand the product is in
	$brands = get_the_terms( $product->get_id(), 'product_brand' );
	if( ! empty( $brands[0] ) ) {
		$brand = $brands[0];
		$brand_id = $brand->term_id;
		// Let's check if the brand applies
		if( ! empty( $discounts_by_brand[$brand_id] ) ) {
			$user_role = $roles[0];
			$rules['amount'][$user_role] = $discounts_by_brand[$brand_id][$user_role];
		}
	}
	
	return $rules;
	
}
add_filter( 'wcfad_role_pricing_rules', 'prefix_role_pricing_rules', 10, 2 );