# settings.py

HOST = '0.0.0.0'      # 主机名

PORT = 5555            # 端口号

buffersize = 1024    # 缓冲大小

ADDR = HOST, PORT    # 地址

languages = ['cn', 'en']      # 'cn' -> 中文

language = 'cn'                # 'en' -> 英文

curuser = ''  # 当前用户

# language.py

from settings import language

if language == 'en':

    administrator = 'Administrator'

    txt_administrator_close_chatroom = 'Chatroom closed by Administrator.'

    txt_uesr_enter_chatroom = 'entered the chatroom.'

    txt_user_quit_chatroom = 'quited the chatroom.'

    txt_username = 'username> '

    txt_user_already_exists = 'Username already exists!'

    txt_connect_to = 'Connected to'

    txt_connect_from = 'Connected from'

elif language == 'cn':

    administrator = '管理员'

    txt_administrator_close_chatroom = '管理员关闭了聊天室。'

    txt_uesr_enter_chatroom = '进入了聊天室。'

    txt_user_quit_chatroom = '退出了聊天室。'

    txt_username = '用户名> '

    txt_user_already_exists = '用户名已存在。'

    txt_connect_to = '连接到'

    txt_connect_from = '连接从'

# server.py

# 导入系统模块

import os, sys

# 导入网络编程（传输层）模块

from socket import *

# IO多路复用模块

from select import select

# 设置模块

from settings import *

# 语言模块

from language import *

def main():

    'main 主函数'

    server = socket(AF_INET, SOCK_STREAM)  # 建立TCP套接字

    server.setsockopt(SOL_SOCKET, SO_REUSEADDR, 1)  # 设置端口可立即重用

    server.bind(ADDR)  # 绑定地址

    server.listen()  # 监听

    # 接收函数

    accept(server)

def accept(server):

    'accept 服务器接受函数'

    # 使用select模块的select方法实现IO多路复用监听传输

    rlist = [server, sys.stdin]

    wlist = []

    xlist = []

    while True:

        rs, ws, xs = select(rlist, wlist, xlist)

        for r in rs:

            if r is server:

                # 服务器接受客户端连接

                conn, addr = server.accept()

                # 调用validate函数检查用户名

                if validate(conn):

                    # 将客户端套接字添加到rlist中以监听

                    rlist.append(conn)

                    # 如果用户名注册成功

                    print(txt_connect_from, addr)

                else:

                    conn.close()

            elif r is sys.stdin:

                # 服务器向所有客户端发送系统（管理员）消息

                data = sys.stdin.readline()

                if data == '\n':

                    # 如果服务器输入回车，则退出

                    for c in rlist[2:]:

                        c.send(b'\n')

                        c.close()

                    server.close()

                    print(txt_administrator_close_chatroom)

                    os._exit(0)

                else:

                    # 如果服务器输入正常语句，通知所有客户端

                    data = administrator + ': ' + data

                    for c in rlist[2:]:

                        c.send(data.encode())

            else:

                # 服务器接受客户端的消息并转发给所有客户端

                data = r.recv(buffersize)

                if not data:

                    # 关闭客户端

                    r.close()

                    rlist.remove(r)

                else:

                    # 转发信息给其他客户端

                    print(data.decode(), end='')

                    for c in rlist[2:]:

                        if c is not r:

                            c.send(data)

def validate(client):

    '检验用户名 validate username'

    name = client.recv(buffersize).decode()

    # print(name.decode())

    # print(users)

    if name in users:

        client.send(b'Username already exists!')

        return False

    else:

        users.append(name)

        client.send(b'Welcome!')

        return True

if __name__ == '__main__':

    # 全局变量，管理用户信息

    users = []

    # 主函数

    main()

# client.py

# 导入系统模块

import os, sys

# 导入网络编程（传输层）模块

from socket import *

# IO多路复用模块

from select import select

# 设置模块

from settings import *

# 语言模块

from language import *

def main():

    'main 主函数'

    client = socket(AF_INET, SOCK_STREAM)  # 建立TCP套接字

    # 登录函数

    if login(client):

        # 连接函数

        connect(client)

def connect(client):

    'connect 客户端连接函数'

    # 使用select模块的select方法实现IO多路复用监听传输

    rlist = [client, sys.stdin]

    wlist = []

    xlist = []

    while True:

        rs, ws, xs = select(rlist, wlist, xlist)

        for r in rs:

            if r is client:

                # 接受服务器发来的消息

                data = client.recv(buffersize)

                if data.decode() == '\n':

                    # 如果消息为回车，聊天室关闭

                    client.close()

                    print(txt_administrator_close_chatroom)

                    os._exit(0)

                else:

                    # 打印接收到的信息

                    print(data.decode(), end='')

            elif r is sys.stdin:

                # 发送消息给服务器

                data = sys.stdin.readline()

                if data == '\n':

                    # 如果回车，发送退出消息，关闭客户端，退出聊天室

                    data = curuser + ': ' + txt_user_quit_chatroom + '\n'

                    client.send(data.encode())

                    client.close()

                    os._exit(0)

                else:

                    # 发信息给服务器

                    data = curuser + ': ' + data

                    client.send(data.encode())

def login(client):

    '登录函数 login'

    # 使用全局变量管理用户

    # 先让客户端输入姓名

    global curuser

    curuser = input(txt_username)

    # 再连接到服务器，传送用户名以检验

    client.connect(ADDR)  # 连接到服务器地址

    print(txt_connect_to, ADDR)

    client.send(curuser.encode())

    data = client.recv(buffersize)

    if data.decode() == 'Username already exists!':

        # 如果用户名已经存在，要求重新输入

        print(txt_user_already_exists)

        return False

    else:

        # 发送信息给服务器，告知服务器用户进入聊天室

        # -*- 因为监听传输的是sys.stdin.readline()，所以必须在最后添加换行符，以便清除阻塞 -*-

        data = curuser + ': ' + txt_uesr_enter_chatroom + '\n'

        client.send(data.encode())

        return True

if __name__ == '__main__':

    main()