EDD Recurring Payments & Discounts

functions.php

<?php
function modify_edd_get_discount_amount( $amount, $code_id ) {
	// Download requirements
	$download_id = 49;
	// Coupon code filtered
	$dcodes = array( 'YOUDONTHINKIKNOW', 'WHATYOURETRYINGTODO?', 'NICETRY!!' );
	// Filter only the discount code above
	$code = edd_get_discount_code( $code_id );
	if ( in_array( $code, $dcodes ) ) {
		// Check cart of requirements before filtering amount
		$cart_items = edd_get_cart_contents();
		$cart_ids = $cart_items ? wp_list_pluck( $cart_items, 'id' ) : null;
		if ( is_array( $cart_ids ) ) {
			// check to make sure the cart has the download this discount applies to
			if ( in_array( $download_id, $cart_ids ) ) {
				// Find the $cart_items key of the download 
				$key = array_search( $download_id, $cart_ids );
				// Check to make sure there's a variable price
				if ( isset( $cart_items[$key]['options']['price_id'] ) ) {
					// Each variable price will have it's own discount.
					switch ( $cart_items[$key]['options']['price_id'] ) {
						case 0: // freelancer mo
							$amount = 9.00;
							break;
						case 1: // freelancer yr
							$amount = 20.00;
							break;
						case 2: // biz mo
							$amount = 15.00;
							break;
						case 3: // biz yr
							$amount = 35.00;
							break;
						
						default:
							break;
					}
				}	
			}
		}
	}
	return (float) $amount;
}
add_filter( 'edd_get_discount_amount', 'modify_edd_get_discount_amount', 10, 2 );