package com.digiwin.utils;

import java.util.Date;

import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.Multipart;
import javax.mail.Transport;
import javax.mail.internet.AddressException;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeBodyPart;
import javax.mail.internet.MimeMessage;
import javax.mail.internet.MimeMultipart;

public class DWMailUtils {

	private static final String MAIL_MIME_CHARSET = "utf8";
	private static final String CONTENT_CHARSET = "text/html; charset=utf8";

	/**
	 * 同步寄信功能
	 *
	 * @param sender-寄件者
	 * @param receiver-收件者
	 * @param ccList-CC
	 * @param smtpHost-伺服器位置
	 * @param port-port
	 * @param username-使用者名稱(登入郵件伺服器)
	 * @param passwd-密碼(登入郵件伺服器)
	 * @param subject-標題
	 * @param content-內容
	 * @param typeOfConnection-連線種類0:TLS,1:SSL
	 * @return
	 * @throws Exception
	 */
	public static boolean doSendMail(String sender, String receiver, String ccList, String bccList, String smtpHost, int port, String username, String passwd, String subject, String content, Integer typeOfConnection) throws Exception {

		Transport transport = null;
		sender = username;// 因為通常寄件者與登入郵件系統帳密是同一組，先固定住以避免額外錯誤，有應用需求再修改掉，sender 的入參是保留此彈性

		try {
			// encoding
			System.setProperty("mail.mime.charset", MAIL_MIME_CHARSET);
			// properties
			java.util.Properties props = setProperties(typeOfConnection, smtpHost, port);
			// construct a mail session
			javax.mail.Session mailSession = javax.mail.Session.getDefaultInstance(props, null);
			mailSession.setDebug(false);

			// Message msg = new MimeMessage(mailSession);
			Message msg = setMsgInfo(mailSession, sender, receiver, ccList, bccList, subject, content);

			if (typeOfConnection == 0) {
				transport = mailSession.getTransport("smtp"); //回傳假的instance
			} else {
				transport = mailSession.getTransport("smtps");
			}
			transport.connect(smtpHost, username, passwd);
			transport.sendMessage(msg, msg.getAllRecipients());

			return true;
		} catch (Exception e) { ///Exception 要測到
			e.printStackTrace();
			return false;
		} finally {
			closeTransport(transport);
		}
	}

	private static void closeTransport(Transport transport) throws MessagingException {
		if (transport != null) {
			transport.close();
		}
	}

	private static Message setMsgInfo(javax.mail.Session mailSession, String sender, String receiver, String ccList, String bccList, String subject, String content) throws AddressException, MessagingException {

		Message msg = new MimeMessage(mailSession);
		// mail sender
		msg.setFrom(new InternetAddress(sender));
		// mail recievers
		InternetAddress[] address = InternetAddress.parse(receiver, false);
		msg.setRecipients(Message.RecipientType.TO, address);
		// mail cc
		if (ccList != null && !ccList.equals("")) {
			msg.setRecipients(Message.RecipientType.CC, InternetAddress.parse(ccList));
		}
		// bcc測試中
		if (bccList != null && !bccList.equals("")) {
			msg.addRecipients(Message.RecipientType.BCC, InternetAddress.parse(bccList));
		}
		// mail's subject
		msg.setSubject(subject);
		// mail's sending time
		msg.setSentDate(new Date());
		MimeBodyPart mbp = new MimeBodyPart();
		// mail's charset
		mbp.setContent(content, CONTENT_CHARSET);
		Multipart mp = new MimeMultipart();
		mp.addBodyPart(mbp);
		msg.setContent(mp);
		return msg;
	}

	private static java.util.Properties setProperties(int typeOfConnection, String smtpHost, int port) {
		java.util.Properties props = null;
		switch (typeOfConnection) {
		case 1: // TLS
			props = getPropertyInTls(smtpHost, port);
			break;
		case 2: // SSL
			props = getPropertyInSsl(smtpHost, port);
			break;
		default:
			props = getPropertyInNormalConnection(smtpHost, port);
			break;
		}
		return props;
	}

	private static java.util.Properties getPropertyInNormalConnection(String smtpHost, int port) {
		java.util.Properties props = new java.util.Properties();
		props.put("mail.host", smtpHost);
		props.put("mail.transport.protocol", "smtp");
		props.put("mail.smtp.port", port);
		props.put("mail.smtp.auth", "true");
		return props;
	}

	private static java.util.Properties getPropertyInTls(String smtpHost, int port) {
		java.util.Properties props = new java.util.Properties();
		props.put("mail.host", smtpHost);
		props.put("mail.smtp.auth", "true");
		props.put("mail.smtp.starttls.enable", "true");
		props.put("mail.smtp.port", port);
		return props;
	}

	private static java.util.Properties getPropertyInSsl(String smtpHost, int port) {
		java.util.Properties props = new java.util.Properties();
		props.put("mail.host", smtpHost);
		props.put("mail.smtps.auth", "true");
		props.put("mail.smtps.port", port);
		props.put("mail.smtps.socketFactory.port", port);
		props.put("mail.smtps.socketFactory.class", "javax.net.ssl.SSLSocketFactory");
		props.put("mail.smtps.socketFactory.fallback", "true");
		props.put("mail.smtps.ssl.enable", "true");
		return props;
	}
}