package org.apidesign.apifest08.test;

import java.math.BigDecimal;

import junit.framework.TestCase;

import org.apidesign.apifest08.currency.ConversionResult;

import org.apidesign.apifest08.currency.Convertor;

import org.apidesign.apifest08.currency.ConvertorCurrency;

import org.apidesign.apifest08.currency.ExchangeRateProvider;

import org.apidesign.apifest08.currency.ConversionNotSupportedException;

/** Finish the Convertor API, and then write bodies of methods inside

 * of this class to match the given tasks. To fullfil your task, use the

 * API define in the <code>org.apidesign.apifest08.currency</code> package.

 * Do not you reflection, or other hacks as your code

 * shall run without any runtime permissions.

 */

public class Task1Test extends TestCase {

    public Task1Test(String testName) {

        super(testName);

    }

    @Override

    protected void setUp() throws Exception {

    }

    @Override

    protected void tearDown() throws Exception {

    }

    /** Create convertor that understands two currencies, CZK and

     *  USD. Make 1 USD == 17 CZK.

     *

     * Creation of the convertor shall not require subclassing of any class

     * or interface on the client side.

     *

     * @return prepared convertor ready for converting USD to CZK and CZK to USD

     */

    public static Convertor createCZKtoUSD() {

        ConvertorCurrency fromCurrency = ConvertorCurrency.getInstance("CZK");

        ConvertorCurrency toCurrency = ConvertorCurrency.getInstance("USD");

        ExchangeRateProvider exchangeRateProvider = new ExchangeRateProvider(new BigDecimal(17), fromCurrency, new BigDecimal(1), toCurrency);

        return Convertor.createConvertor(exchangeRateProvider);

    }

    /** Create convertor that understands two currencies, CZK and

     *  SKK. Make 100 SKK == 80 CZK.

     *

     * Creation of the convertor shall not require subclassing of any class

     * or interface on the client side.

     * 

     * @return prepared convertor ready for converting SKK to CZK and CZK to SKK

     */

    public static Convertor createSKKtoCZK() {

        ConvertorCurrency fromCurrency = ConvertorCurrency.getInstance("SKK");

        ConvertorCurrency toCurrency = ConvertorCurrency.getInstance("CZK");

        ExchangeRateProvider exchangeRateProvider = new ExchangeRateProvider(new BigDecimal(100), fromCurrency, new BigDecimal(80), toCurrency);

        return Convertor.createConvertor(exchangeRateProvider);

    }

    public static Convertor createCZKtoYEN() {

        ConvertorCurrency fromCurrency = ConvertorCurrency.getInstance("CZK");

        ConvertorCurrency toCurrency = ConvertorCurrency.getInstance("JPY");

        ExchangeRateProvider exchangeRateProvider = new ExchangeRateProvider(new BigDecimal(1), fromCurrency, new BigDecimal(1), toCurrency);

        return Convertor.createConvertor(exchangeRateProvider);

    }

    /** Use the convertor from <code>createCZKtoUSD</code> method and do few conversions

     * with it.

     */

    public void testCurrencyCZKUSD() throws Exception {

        Convertor convertCzkUsd = createCZKtoUSD();

        {

            // convert $1 to CZK using c:

            ConversionResult result = convertCzkUsd.convertBack(new BigDecimal(1));

            assertEquals("Result is 17 CZK", new BigDecimal("17.00"), result.getConverted());

            assertEquals("No Remainer", BigDecimal.ZERO, result.getRemainder());

        }

        {

            // convert 17CKZ to $ using c:

            ConversionResult result = convertCzkUsd.convert(new BigDecimal(17));

            assertEquals("Result is 1 $", new BigDecimal("1.00"), result.getConverted());

            assertEquals("No Remainer", BigDecimal.ZERO, result.getRemainder());

        }

        {

            // convert $5 to CZK using c:

            ConversionResult result = convertCzkUsd.convertBack(new BigDecimal(5));

            assertEquals("Result is 85 CZK", new BigDecimal("85.00"), result.getConverted());

            assertEquals("No Remainer", BigDecimal.ZERO, result.getRemainder());

        }

        {

            // convert $8 to CZK

            ConversionResult result = convertCzkUsd.convertBack(new BigDecimal(8));

            assertEquals("Result is 136 CZK", new BigDecimal("136.00"), result.getConverted());

            assertEquals("No Remainer", BigDecimal.ZERO, result.getRemainder());

        }

        {

            // convert 1003CZK to USD

            ConversionResult result = convertCzkUsd.convert(new BigDecimal(1003));

            assertEquals("Result is 59 USD", new BigDecimal("59.00"), result.getConverted());

            assertEquals("No Remainer", BigDecimal.ZERO, result.getRemainder());

        }

    }

    /** Use the convertor from <code>createSKKtoCZK</code> method and do few conversions

     * with it.

     */

    public void testCurrencySKKCZK() throws Exception {

        Convertor convertSkkCzk = createSKKtoCZK();

        {

            // convert 100SKK using c:

            ConversionResult result = convertSkkCzk.convert(new BigDecimal(100));

            assertEquals("Result is 80 CZK", new BigDecimal("80.00"), result.getConverted());

        }

        {

            // convert 80CZK using c:

            ConversionResult result = convertSkkCzk.convertBack(new BigDecimal(80));

            assertEquals("Result is 100 SKK", new BigDecimal("100.00"), result.getConverted());

        }

        {

            // convert 16CZK using c:

            ConversionResult result = convertSkkCzk.convertBack(new BigDecimal(16));

            assertEquals("Result is 20 SKK", new BigDecimal("20.00"), result.getConverted());

        }

        {

            // convert 500SKK to CZK

            ConversionResult result = convertSkkCzk.convert(new BigDecimal(500));

            assertEquals("Result is 400 CZK", new BigDecimal("400.00"), result.getConverted());

            assertEquals("No Remainer", BigDecimal.ZERO, result.getRemainder());            

        }

        {

            // convert 501SKK to CZK

            ConversionResult result = convertSkkCzk.convert(new BigDecimal(501));

            assertEquals("Result is 400 CZK", new BigDecimal("400.80"), result.getConverted());

            assertEquals("No Remainer", BigDecimal.ZERO, result.getRemainder());

        }

    }

    /**

     * Convert SKK to CZK. Convertor can't convert whole amout (can't convert one SKK cent to CZK). Remaining

     * amount is stored in remainder result.

     * 

     * Test is currently failing, because implementation can't handle this case.

     */

//    public void testConvertSmallUnits_failing() {

//        Convertor convertSkkCzk = createSKKtoCZK();

//        {

//            // convert 501SKK to CZK

//            ConversionResult result = convertSkkCzk.convert(new BigDecimal("501.01"));

//            assertEquals("Result is 400 CZK", new BigDecimal("400.80"), result.getConverted());

//            assertEquals("No Remainer", new BigDecimal("0.01"), result.getRemainder());

//            

//        }

//        

//    }

    /**

     * Test converting from CZK to JPY. Remained has scale of CZK.

     * 

     * This test is currently failing, because converter implementation currently can't handle conversion from "cent" to "no-cent" currency.

     */

//    public void testConvertCzkToJpy_failing() {

//        Convertor convertSkkCzk = createCZKtoYEN();

//        {

//            // convert 501SKK to CZK

//            ConversionResult result = convertSkkCzk.convert(new BigDecimal("120.00"));

//            assertEquals("Result is 120 YEN", new BigDecimal("120"), result.getConverted());

//            assertEquals("No Remainer", new BigDecimal("0.00"), result.getRemainder());

//            

//        }

//    }

    /**

     * Test converting from JPY to CZK. Remained has scale of JPY.

     * 

     * This test is currently failing, because converter implementation currently can't handle conversion from "cent" to "no-cent" currency.

     */

//    public void testConvertJpyToCzk_failing() {

//        Convertor convertSkkCzk = createCZKtoYEN();

//        {

//            // convert 501SKK to CZK

//            ConversionResult result = convertSkkCzk.convert(new BigDecimal("120.00"));

//            assertEquals("Result is 120 YEN", new BigDecimal("120"), result.getConverted());

//            assertEquals("No Remainer", new BigDecimal("0"), result.getRemainder());

//            

//        }

//    }

    public void testCannotConvertToSKKwithCZKUSDConvertor() throws Exception {

            Convertor c = createCZKtoUSD();

            // convert $5 to SKK, the API shall say this is not possible

            try {

                c.convert(ConvertorCurrency.getInstance("USD"), ConvertorCurrency.getInstance("SKK"), new BigDecimal(5));

                fail();

            } catch (ConversionNotSupportedException e) {

                //expected error;

                assertEquals("Exception From USD", "USD",e.getFromCurrecyCode());

                assertEquals("Exception To SKK", "SKK",e.getToCurrecyCode());

            }

            // convert 500 SKK to CZK, the API shall say this is not possible

            try {

                c.convert(ConvertorCurrency.getInstance("SKK"), ConvertorCurrency.getInstance("CZK"), new BigDecimal(500));

                fail();

            } catch (ConversionNotSupportedException e) {

                assertEquals("Exception From USD", "SKK",e.getFromCurrecyCode());

                assertEquals("Exception To SKK", "CZK",e.getToCurrecyCode());            }

    }

}