package org.springframework.samples.jpetstore.domain.logic;

import java.lang.reflect.Method;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import org.springframework.aop.AfterReturningAdvice;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.mail.MailException;
import org.springframework.mail.MailSender;
import org.springframework.mail.SimpleMailMessage;
import org.springframework.samples.jpetstore.domain.Account;
import org.springframework.samples.jpetstore.domain.Order;

/**
 * AOP advice that sends confirmation email after order has been submitted
 * @author Dmitriy Kopylenko
 */
public class SendOrderConfirmationEmailAdvice implements AfterReturningAdvice, InitializingBean {

	private static final String DEFAULT_MAIL_FROM = "jpetstore@springframework.org";

	private static final String DEFAULT_SUBJECT = "Thank you for your order!";

	private final Log logger = LogFactory.getLog(getClass());

	private MailSender mailSender;

	private String mailFrom = DEFAULT_MAIL_FROM;

	private String subject = DEFAULT_SUBJECT;

	public void setMailSender(MailSender mailSender) {
		this.mailSender = mailSender;
	}

	public void setMailFrom(String mailFrom) {
		this.mailFrom = mailFrom;
	}

	public void setSubject(String subject) {
		this.subject = subject;
	}

	public void afterPropertiesSet() throws Exception {
		if (this.mailSender == null) {
			throw new IllegalStateException("mailSender is required");
		}
	}

	public void afterReturning(Object returnValue, Method m, Object[] args, Object target) throws Throwable {
		Order order = (Order) args[0];
		Account account = ((PetStoreFacade) target).getAccount(order.getUsername());

		// don't do anything if email address is not set
		if (account.getEmail() == null || account.getEmail().length() == 0) {
			return;
		}

		StringBuffer text = new StringBuffer();
		text.append("Dear ").append(account.getFirstName()).append(' ').append(account.getLastName());
		text.append(", thank your for your order from JPetStore. Please note that your order number is ");
		text.append(order.getOrderId());

		SimpleMailMessage mailMessage = new SimpleMailMessage();
		mailMessage.setTo(account.getEmail());
		mailMessage.setFrom(this.mailFrom);
		mailMessage.setSubject(this.subject);
		mailMessage.setText(text.toString());
		try {
			this.mailSender.send(mailMessage);
		}
		catch (MailException ex) {
			// just log it and go on
			logger.warn("An exception occured when trying to send email", ex);
		}
	}

}