package com.bj58.ecat.emc.diywebsite.tongji.wltsync.util;

import java.util.Properties;

import javax.activation.DataHandler;
import javax.mail.Address;
import javax.mail.Message;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeBodyPart;
import javax.mail.internet.MimeMessage;
import javax.mail.internet.MimeMultipart;
import javax.mail.internet.MimeUtility;
import javax.mail.util.ByteArrayDataSource;

/**
 * 邮件处理类，基本用法如下：<br>
 * Mails.create().subject("标题").body("内容 ").send();<br>
 * 多次调用 {@link #body(bodyContent)} 或者 {@link #attachment(name, type, bytes)}
 * 可以多次添加邮件内容或者附件
 * @author lzxz1234<lzxz1234@gmail.com>
 */
public class Mails {

    private static final String host = Configs.getProperty("email.host");
    private static final String smtphost = Configs.getProperty("email.host.smtp");
    private static final String username = Configs.getProperty("email.user");
    private static final String password = Configs.getProperty("email.pass");
    private static final String fromEmail = username + "@" + host;
    public static final String[] receiveMails = Configs.getProperty(String[].class, "email.receivers");

    private Session session;
    private MimeMessage message;

    /**
     * 创建邮件对象的工厂类
     * @return
     * @throws Exception
     */
    public static Mails create() throws Exception {

        Properties prop = new Properties();
        prop.setProperty("mail.host", smtphost);
        prop.setProperty("mail.transport.protocol", "smtp");
        prop.setProperty("mail.smtp.auth", "true");
        prop.setProperty("mail.smtp.starttls.enable","true");
        Mails result = new Mails();
        result.session = Session.getInstance(prop);
        return result;
    }

    /**
     * 执行发送操作
     * @return
     * @throws Exception
     */
    public Mails send() throws Exception {

        message.saveChanges();
        Transport ts = session.getTransport();
        ts.connect(smtphost, username, password);
        ts.sendMessage(message, message.getAllRecipients());
        ts.close();
        return this;
    }

    /**
     * 设置邮件标题
     * @param subject
     * @return
     * @throws Exception
     */
    public Mails subject(String subject) throws Exception {

        message = new MimeMessage(session);
        message.setFrom(new InternetAddress(fromEmail));
        message.setRecipients(Message.RecipientType.TO, getRecipient());
        message.setSubject(subject);
        message.setContent(new MimeMultipart("mixed"));
        return this;
    }

    /**
     * 添加邮件体，支持 HTML 标签
     * @param bodyContent
     * @return
     * @throws Exception
     */
    public Mails body(String bodyContent) throws Exception {

        MimeBodyPart text = new MimeBodyPart();
        text.setContent(bodyContent, "text/html;charset=UTF-8");
        ((MimeMultipart)message.getContent()).addBodyPart(text);
        return this;
    }

    /**
     * 添加附件
     * @param name 附件名称
     * @param type 附件 MIME 值
     * @param bytes 附件体
     * @return
     * @throws Exception
     */
    public Mails attachment(String name, String type, byte[] bytes) throws Exception {

        MimeBodyPart attach = new MimeBodyPart();
        DataHandler dh = new DataHandler(new ByteArrayDataSource(bytes, type));
        attach.setDataHandler(dh);
        attach.setFileName(MimeUtility.encodeWord(name));
        ((MimeMultipart)message.getContent()).addBodyPart(attach);
        return this;
    }

    private static Address[] getRecipient() throws Exception {

        InternetAddress[] result = new InternetAddress[receiveMails.length];
        for(int i = 0; i < receiveMails.length; i ++)
            result[i] = new InternetAddress(receiveMails[i]);
        return result;
    }

}