package cz.fi.muni.pa165;

import java.math.BigDecimal;
import java.util.Currency;
import org.junit.Before;
import org.junit.Rule;
import org.junit.Test;
import org.junit.rules.ExpectedException;
import org.junit.runner.RunWith;
import org.mockito.Mock;
import org.mockito.runners.MockitoJUnitRunner;

import static org.mockito.Mockito.*;
import static org.junit.Assert.*;

interface ExchangeRateTable {

    BigDecimal getExchangeRate(Currency sourceCurency, Currency targCurrency);

}

class CurrencyConvertor {

    private final ExchangeRateTable exchangeRateTable;

    public CurrencyConvertor(ExchangeRateTable exchangeRateTable) {
        this.exchangeRateTable = exchangeRateTable;
    }

    public BigDecimal convert(Currency sourceCurency, Currency targCurrency, BigDecimal amount) {
        throw new UnsupportedOperationException();
    }

}

@RunWith(MockitoJUnitRunner.class)
public class ExampleTest {

    @Rule
    public final ExpectedException expectedException = ExpectedException.none();

    @Mock
    private ExchangeRateTable exchangeRateTable;

    private CurrencyConvertor currencyConvertor;

    private final static Currency CZK = Currency.getInstance("CZK");
    private final static Currency EUR = Currency.getInstance("EUR");

    @Before
    public void init() {
        currencyConvertor = new CurrencyConvertor(exchangeRateTable);
    }

    @Test(expected = IllegalArgumentException.class)
    public void testNullArgument() {
        currencyConvertor.convert(null, CZK, BigDecimal.ONE);
    }

    @Test
    public void testNullArgument2() {
        // test initialization
        expectedException.expect(IllegalArgumentException.class);
        currencyConvertor.convert(null, CZK, BigDecimal.ONE);
    }

    @Test
    public void testSomeMethod() {

        when(exchangeRateTable.getExchangeRate(EUR, CZK))
                .thenReturn(new BigDecimal("25.38"));

        BigDecimal result = currencyConvertor.convert(EUR, CZK, BigDecimal.ONE);

        assertEquals(new BigDecimal("25.38"), result);

    }

    @Test
    public void testExceptionThrown() {
        when(exchangeRateTable.getExchangeRate(EUR, CZK))
                .thenThrow(new RuntimeException());

        currencyConvertor.convert(EUR, CZK, BigDecimal.ONE);

    }

}