<?php

function custom_referral_amounts( $referral_amount, $affiliate_id, $amount, $reference, $product_id ) {

	$user_id 		= affwp_get_affiliate_user_id( $affiliate_id );
	$member 		= new MeprUser( $user_id );
	$subscriptions 	= array_unique( $member->active_product_subscriptions( 'products' ) );

	$user_level = 'freshman';

	foreach( $subscriptions as $product ) {

		if( strpos($product->post_title, 'Sophomore') !== false ) {

			$user_level = 'sophomore';
			break;

		} elseif( strpos($product->post_title, 'Junior') !== false ) {

			$user_level = 'junior';
			break;

		} elseif( strpos($product->post_title, 'Senior') !== false ) {

			$user_level = 'senior';
			break;

		} elseif( strpos($product->post_title, 'Graduate') !== false ) {

			$user_level = 'graduate';
			break;

		}

	}

	// Now we know the user level

	if( $user_level == 'freshman' ) {

		$referral_amount = $amount * 0.20;

		if( $referral_amount > 10 ) {
			$referral_amount = 10;
		}

	} elseif( $user_level == 'sophomore' ) {

		$referral_amount = $amount * 0.50;

		if( $referral_amount > 25 ) {
			$referral_amount = 25;
		}

	} elseif( $user_level == 'junior' ) {

		$referral_amount = $amount * 0.50;

		if( $referral_amount > 100 ) {
			$referral_amount = 100;
		}

	} elseif( $user_level == 'senior' ) {

		$referral_amount = $amount * 0.50;

		if( $referral_amount > 250 ) {
			$referral_amount = 250;
		}

	} elseif( $user_level == 'graduate' ) {

		$referral_amount = $amount * 0.50;

		if( $referral_amount > 500 ) {
			$referral_amount = 500;
		}

	}

	return $referral_amount;

}

add_filter( 'affwp_calc_referral_amount', 'custom_referral_amounts', 10, 5 );