#!/usr/bin/env python3.7
import socket       # socket, AF_INET, SOCK_STREAM, SOL_SOCKET, SO_REUSEADDR
import logging
import threading
import ClientConnection


class Server(object):
    """
    A simple chat application server
    """
    clients = []

    soc = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    soc.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)

    def __init__(self, host: str, port: int, maxClients=64):
        self.host = host
        self.port = port
        self.soc.bind((host, port))
        self.maxClients = maxClients

    def run(self) -> None:
        """
        Start the server and start to listen for incoming connection
        """
        self.soc.listen(self.maxClients)
        logging.info('Start listening on {}:{} maximum {} clients'.format(
            self.host, self.port, self.maxClients))
        while True:
            conn, addr = self.soc.accept()
            client = ClientConnection.ClientConnection(self, conn, addr)
            msg = '{} has joined the chat.'.format(client.addr)
            self._announce(msg)
            self.clients.append(client)
            t = threading.Thread(target=client.serve)
            t.daemon = True
            t.start()

    def removeClient(self, client: ClientConnection.ClientConnection) -> None:
        """
        Remove client from this server list of connected clients
        """
        msg = '{} has left the chat.'.format(client.nameFormat())
        self.clients.remove(client)
        self._announce(msg)

    def _announce(self, announcement: str) -> None:
        """
        Send announcement from system to all connected clients
        """
        msg = '[system] {}'.format(announcement)
        logging.info(msg)
        for client in self.clients:
            client.send(msg)

    def sendToAll(self, sender: ClientConnection.ClientConnection, msg: str) -> None:
        """
        Broadcast message from one client to other clients
        """
        msg = '{} {}'.format(sender.nameFormat(), msg)
        logging.info(msg)
        for client in self.clients:
            if client != sender:
                client.send(msg)