package org.apidesign.apifest08.currency;

import java.io.Serializable;

import java.math.BigDecimal;

import java.util.Currency;

/**

 * Default implementation of {@link Money} interface. This class is immutable.

 * @author lukas

 *

 */

public final class MoneyImpl implements Serializable, Money{

	private static final long serialVersionUID = -6091808475616516136L;

	private final BigDecimal amount;

	private final Currency currency;

	public MoneyImpl(BigDecimal amount, Currency currency) {

		if (amount==null) throw new NullPointerException("Amount is null");

		if (currency==null) throw new NullPointerException("Currency is null"+currency);

		this.amount = amount;

		this.currency = currency;

	}

	public MoneyImpl(long amount, Currency currency) {

		this(BigDecimal.valueOf(amount), currency);

	}

	public MoneyImpl(double amount, Currency currency) {

		this(BigDecimal.valueOf(amount), currency);

	}

	/**

	 * Factory method.

	 * @param amount

	 * @param currency

	 * @return

	 */

	public static final Money money(BigDecimal amount, Currency currency)

	{

		return new MoneyImpl(amount, currency);

	}

	/**

	 * Factory method.

	 * @param amount

	 * @param currency

	 * @return

	 */

	public static final Money money(long amount, Currency currency)

	{

		return new MoneyImpl(amount, currency);

	}

	/**

	 * Factory method.

	 * @param amount

	 * @param currency

	 * @return

	 */

	public static final Money money(double amount, Currency currency)

	{

		return new MoneyImpl(amount, currency);

	}

	/**

	 * Returns amount.

	 * @return

	 */

	public BigDecimal getAmount() {

		return amount;

	}

	/**

	 * Returns currency.

	 */

	public Currency getCurrency() {

		return currency;

	}

	@Override

	public int hashCode() {

		final int prime = 31;

		int result = 1;

		result = prime * result + ((amount == null) ? 0 : amount.hashCode());

		result = prime * result

				+ ((currency == null) ? 0 : currency.hashCode());

		return result;

	}

	@Override

	public boolean equals(Object obj) {

		if (this == obj)

			return true;

		if (obj == null)

			return false;

		if (!(obj instanceof MoneyImpl))

			return false;

		MoneyImpl other = (MoneyImpl) obj;

		if (amount == null) {

			if (other.amount != null)

				return false;

		} else if (amount.compareTo(other.amount)!=0)

			return false;

		if (currency == null) {

			if (other.currency != null)

				return false;

		} else if (!currency.equals(other.currency))

			return false;

		return true;

	}

	@Override

	public String toString() {

		return getClass().getName()+"["+currency+amount+"]";

	}

}