ItemTotalAllowanceChargeCalculatorTest.java

package io.konik.validation;

import com.neovisionaries.i18n.CurrencyCode;
import io.konik.util.Amounts;
import io.konik.zugferd.entity.AllowanceCharge;
import io.konik.zugferd.entity.GrossPrice;
import io.konik.zugferd.entity.trade.item.Item;
import io.konik.zugferd.entity.trade.item.SpecifiedAgreement;
import io.konik.zugferd.unqualified.Amount;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;

import java.math.BigDecimal;
import java.util.Arrays;
import java.util.Collection;
import java.util.Random;

import static io.konik.validation.AmountCalculator.ItemTotalAllowanceChargeCalculator;
import static java.math.BigDecimal.valueOf;
import static org.assertj.core.api.Assertions.assertThat;
import static org.junit.runners.Parameterized.Parameter;
import static org.junit.runners.Parameterized.Parameters;

@RunWith(Parameterized.class)
public class ItemTotalAllowanceChargeCalculatorTest {

	private static final CurrencyCode CURRENCY_CODE = CurrencyCode.USD;
	private static final Random RANDOM = new Random();

	@Parameters(name = "Calculating expected total allowance charge = {0} USD")
	public static Collection<Object[]> data() {
		return Arrays.asList(new Object[][]{
				{ BigDecimal.ZERO, new AllowanceCharge[] {} },
				{ valueOf(1), new AllowanceCharge[] { charge(valueOf(1)) } },
				{ valueOf(5.23), new AllowanceCharge[] { charge(valueOf(0.23)), charge(valueOf(2.00)), charge(valueOf(1.5)), charge(valueOf(1.5)) } },
				{ valueOf(2), new AllowanceCharge[] { charge(valueOf(5.01)), charge(valueOf(-3.01)) } }
		});
	}

	@Parameter
	public BigDecimal expectedTotalAllowanceCharge;

	@Parameter(1)
	public AllowanceCharge[] allowanceCharges;

	@Test
	public void test() {
		//given:
		Item item = createItem();
		ItemTotalAllowanceChargeCalculator calculator = new ItemTotalAllowanceChargeCalculator(CURRENCY_CODE);

		//when:
		Amount totalAllowanceCharge = calculator.apply(item);

		//then:
		assertThat(totalAllowanceCharge.getValue())
				.isEqualByComparingTo(expectedTotalAllowanceCharge);
	}

	private Item createItem() {
		Item item = new Item();
		GrossPrice grossPrice = new GrossPrice(Amounts.zero(CURRENCY_CODE));
		grossPrice.addAllowanceCharge(allowanceCharges);

		SpecifiedAgreement agreement = new SpecifiedAgreement();
		agreement.setGrossPrice(grossPrice);

		item.setAgreement(agreement);
		return item;
	}

	private static AllowanceCharge charge(final BigDecimal value) {
		AllowanceCharge charge = new AllowanceCharge();
		charge.setActual(new Amount(value.abs(), CURRENCY_CODE));

		if (value.signum() < 0) {
			charge.setDiscount();
		} else {
			charge.setSurcharge();
		}
		return charge;
	}
}