import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.net.Socket;
import java.net.UnknownHostException;
import java.util.StringTokenizer;

import sun.misc.BASE64Encoder;

public class SendMailImp implements SendMail {
    public static final int SINA = 0;
    public static final int QQ = 1;
    public static final int FOXMAIL = 2;
    public static final int WANGYI163 = 3;
    public static final int WANGYI126 = 8;
    public static final int YEAH = 4;
    public static final int HOTMAIL = 5;
    public static final int YAHOO = 6;
    public static final int GMAIL = 7;

    /** 用于向服务器发起连接 */
    private Socket socket = null;
    /** 与服务器连接后的输入流 */
    private BufferedReader input = null;
    /** 与服务器连接后的输出流 */
    private BufferedWriter output = null;
    /** 发送邮件服务器名称 */
    private String server = null;
    /** 发送端口号 */
    private int port;
    /** 邮件信息 */
    private MailMessage message;

    public MailMessage getMessage() {
        return message;
    }

    //设置邮件的信息内容，以方法链的方式实现
    public SendMailImp setMessage (MailMessage message) {
        this.message = message;
        return this;
    }

    public Socket getSocket() {
        return socket;
    }

    public void setSocket (Socket socket) {
        this.socket = socket;
    }

    public BufferedReader getInput() {
        return input;
    }

    public void setInput (BufferedReader input) {
        this.input = input;
    }

    public BufferedWriter getOutput() {
        return output;
    }

    public void setOutput (BufferedWriter output) {
        this.output = output;
    }

    public String getServer() {
        return server;
    }

    public void setServer (String server) {
        this.server = server;
    }

    public int getPort() {
        return port;
    }

    public void setPort (int port) {
        this.port = port;
    }

    /**
     * 根据邮箱类型，设置发送邮件服务器和端口号
     */
    public static SendMailImp getInstance (int sendMailType) {
        SendMailImp sendMailImp = new SendMailImp();
        switch (sendMailType) {
        case SINA:
            sendMailImp.setServer ("smtp.sina.com");
            sendMailImp.setPort (25);
            break;
        case QQ:
        case FOXMAIL:
            sendMailImp.setServer ("smtp.qq.com");
            sendMailImp.setPort (25);
            break;
        case WANGYI126:
            sendMailImp.setServer ("smtp.126.com");
            sendMailImp.setPort (25);
            break;
        case WANGYI163:
            sendMailImp.setServer ("smtp.163.com");
            sendMailImp.setPort (25);
            break;
        case YEAH:
            sendMailImp.setServer ("smtp.yeah.net");
            sendMailImp.setPort (25);
            break;
        case YAHOO:
            sendMailImp.setServer ("smtp.mail.yahoo.com");
            sendMailImp.setPort (465);
            break;
        case GMAIL:
            sendMailImp.setServer ("smtp.gmail.com");
            sendMailImp.setPort (465);
            break;
        case HOTMAIL:
            sendMailImp.setServer ("smtp.live.com");
            sendMailImp.setPort (25);
            break;
        default:
            break;
        }

        try {
            // 与发送邮件服务器建立Socket连接,并得到输入输出流
            Socket socket = new Socket (sendMailImp.getServer(), sendMailImp
                                        .getPort() );
            BufferedReader input = new BufferedReader (new InputStreamReader (
                        socket.getInputStream() ) );
            BufferedWriter output = new BufferedWriter (new OutputStreamWriter (
                        socket.getOutputStream() ) );

            sendMailImp.setSocket (socket);
            sendMailImp.setInput (input);
            sendMailImp.setOutput (output);
        } catch (UnknownHostException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

        return sendMailImp;
    }

    public int sendToServer (String order) {
        try {
            this.getOutput().write (order);
            this.getOutput().newLine();
            this.getOutput().flush();

            System.out.println ("已发送命令:" + order);
        } catch (IOException e) {
            e.printStackTrace();
        }

        return getResult();
    }

    public int getResult() {
        String line = "";
        try {
            line = this.getInput().readLine();
            System.out.println ("服务器返回状态：" + line);
        } catch (IOException e) {
            e.printStackTrace();
        }

        // 从服务器返回消息中取得状态码,并转换成整数返回
        StringTokenizer get = new StringTokenizer (line, " ");
        return Integer.parseInt (get.nextToken() );
    }

    public void regist() throws IOException {
        int result = getResult();
        // 连接上服务器后，服务器给出220应答
        if (result != 220) {
            throw new IOException ("连接服务器失败");
        }

        result = sendToServer ("HELO " + this.getServer() );
        // HELO命令成功后，服务器返回250应答
        if (result != 250) {
            throw new IOException ("注册邮件服务器失败");
        }
    }

    public void login() throws IOException {
        BASE64Encoder encode = new BASE64Encoder();

        int result = sendToServer ("AUTH LOGIN");
        // 登陆服务成功，服务器返回334应答
        if (result != 334) {
            throw new IOException ("登陆服务失败");
        }

        // 对邮箱用户名进行验证
        result = sendToServer (encode.encode (this.message.getUser().getBytes() ) );
        if (result != 334) {
            throw new IOException ("用户名错误");
        }

        // 对邮箱密码进行验证
        result = sendToServer (encode.encode (message.getPassword().getBytes() ) );
        if (result != 235) {
            throw new IOException ("用户验证错误");
        }
    }

    public void setMailFrom() throws IOException {
        int result = sendToServer ("MAIL FROM:<" + this.getMessage().getFrom()
        + ">");
        if (result != 250) {
            throw new IOException ("邮件源地址错误");
        }
    }

    public void setMailTo() throws IOException {
        int result = sendToServer ("RCPT TO:<" + this.getMessage().getTo() + ">");
        if (result != 250) {
            throw new IOException ("邮件目的地址错误");
        }
    }

    public void setData() throws IOException {
        int result = sendToServer ("DATA");
        // 输入date回车后,若收到354应答后,继续输入邮件内容
        if (result != 354) {
            throw new IOException ("不能发送数据");
        }

        this.getOutput().write ("FROM:" + this.getMessage().getDatafrom() );
        this.getOutput().newLine();
        this.getOutput().write ("TO:" + this.getMessage().getDatato() );
        this.getOutput().newLine();
        this.getOutput().write ("SUBJECT:" + this.getMessage().getSubject() );
        this.getOutput().newLine();
        this.getOutput().newLine();
        this.getOutput().write (this.getMessage().getContent() );
        this.getOutput().newLine();

        // 句点加回车结束邮件内容输入
        result = sendToServer (".");
        if (result != 250) {
            throw new IOException ("发送数据错误");
        }
    }

    public void quit() throws IOException {
        int result = sendToServer ("QUIT");
        if (result != 221) {
            throw new IOException ("未能正确退出");
        }

        this.getInput().close();
        this.getOutput().close();
    }

    public boolean sendMail() {
        boolean success = true;
        try {
            // 注册到发送邮件服务器
            regist();
            // 登陆到服务器
            login();
            // 设置邮件源地址
            setMailFrom();
            // 设置邮件目的地址
            setMailTo();
            // 设置邮件体
            setData();
            // 退出邮件
            quit();
        } catch (Exception e) {
            e.printStackTrace();
            success = false;
        }
        return success;
    }
}