"""
聊天室 客户端
"""
from socket import *
from multiprocessing import Process
import re

# 服务器地址
ADDR = ("121.5.90.43", 8888)


# 名字验证：3-10位数字字母下划线-构成,不能以数字和-开头
def check(name):
    if re.search(r"^[_a-zA-Z][-\w]{2,9}$", name):
        return True
    else:
        return False


# 进入聊天室
def login(sock):
    while True:
        name = input("请输入昵称:")
        if not check(name):
            print("3-10位数字字母下划线-构成,不能以数字或-开头")
            continue
        msg = "LOGIN " + name  # 组织格式
        sock.sendto(msg.encode(), ADDR)
        result, addr = sock.recvfrom(128)
        if result == b"Y":
            print("您已进入聊天室")
            return name
        else:
            print("该昵称已存在")


# 子进程
def recv_msg(sock):
    while True:
        data, addr = sock.recvfrom(1024 * 10)
        print("\n" + data.decode() + "\n发言:", end='')


def chat(sock, name):
    p = Process(target=recv_msg, args=(sock,), daemon=True)
    p.start()
    while True:
        content = input("发言:")
        if not content:
            continue
        if content == "quit":
            break
        msg = "CHAT %s %s" % (name, content)
        sock.sendto(msg.encode(), ADDR)


def quit(sock, name):
    msg = "QUIT " + name
    sock.sendto(msg.encode(), ADDR)
    print("您已退出群聊，谢谢使用")


def main():
    sock = socket(AF_INET, SOCK_DGRAM)

    name = login(sock)  # 进入
    try:
        chat(sock, name)  # 聊天
    except:
        pass
    quit(sock, name)  # 退出


if __name__ == '__main__':
    main()