/*
* LumaQQ - Java QQ Client
*
* Copyright (C) 2004 luma <stubma@163.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
package edu.tsinghua.lumaqq.qq.packets.out;

import java.nio.ByteBuffer;

import edu.tsinghua.lumaqq.qq.PacketParseException;
import edu.tsinghua.lumaqq.qq.QQ;
import edu.tsinghua.lumaqq.qq.packets.OutPacket;


/**
 * <pre>
 * QQ登錄請求包，格式為
 * 1. 頭部
 * 2. 初始密鑰，16字節
 * 3. 用戶的密碼密鑰加密一個空串得到的16字節
 * 4. 一個字節0
 * 5. 4字節IP，這里是空
 * 6. 2字節端口，這里是空
 * 7. 19個字節的固定內容
 * 8. 登錄模式，隱身登錄還是什么
 * 9. 16個字節的固定內容
 * 10. 尾部
 * </pre>
 *
 * @author 馬若劼
 */
public class LoginPacket extends OutPacket {    
    /**
     * 構造函數
     */
    public LoginPacket() {
        super(QQ.QQ_CMD_LOGIN, true);
    }
	
    /**
     * @param buf
     * @param length
     * @throws PacketParseException
     */
    public LoginPacket(ByteBuffer buf, int length) throws PacketParseException {
        super(buf, length);
    }
    
    /* (non-Javadoc)
     * @see edu.tsinghua.lumaqq.qq.packets.OutPacket#putBody(java.nio.ByteBuffer)
     */
    protected void putBody(ByteBuffer buf) {
        // 初始密鑰
        buf.put(QQ.iniKey);
        // 創建登陸信息數組
        byte[] login = new byte[QQ.QQ_LOGIN_DATA_LENGTH];
        // 開始填充登陸信息
        // 頭16個字節用md5處理的密碼加密一個空字符串，這用來在服務器端校驗密碼
        System.arraycopy(crypter.encrypt("".getBytes(), user.getPasswordKey()), 0, login, 0, 16);
        // 第16個字節是0
        login[16] = 0;
        // 17-20字節存放IP，現在置空
        login[17] = login[18] = login[19] = login[20] = 0;
        // 21-22字節存放端口，現在置空
        login[21] = login[22] = 0;
        // 23-51字節是固定內容
        System.arraycopy(QQ.login_23_51, 0, login, 23, 29);
        // 52字節是登陸模式
        login[52] = user.getLoginMode();
        // 53-68字節是固定內容，也許是和不同的機器有關
        System.arraycopy(QQ.login_53_68, 0, login, 53, 16);
        // 加密登錄信息
        login = crypter.encrypt(login, QQ.iniKey);
        // 寫入登錄信息
        buf.put(login);
    }
    
    /* (non-Javadoc)
     * @see edu.tsinghua.lumaqq.qq.packets.OutPacket#parseBody(java.nio.ByteBuffer)
     */
    protected void parseBody(ByteBuffer buf) throws PacketParseException {
    }
}