import socket
import sys
import select

SERVER_HOST = 'localhost'
SERVER_PORT = 8181
BUFFER_SIZE = 1024

def main():
    # create a socket object
    client_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    try:
        # connect to the server
        client_socket.connect((SERVER_HOST, SERVER_PORT))
        print(f"Connected to chat server at {SERVER_HOST}:{SERVER_PORT}")
        
        while True:
            # use select to wait for either server messages or user input
            read_sockets, _, _ = select.select([client_socket, sys.stdin], [], [])
            
            for sock in read_sockets:
                if sock == client_socket:
                    # receive message from server
                    server_message = client_socket.recv(BUFFER_SIZE).decode('utf-8')
                    if not server_message:
                        print("Disconnected from server")
                        return
                    print(f"\n{server_message}")
                    print("> ", end="", flush=True)
                else:
                    # prompt for user input
                    client_message = input()
                    if client_message.strip() == "%!":
                        print("Exiting chat...")
                        return
                    
                    # send message to server
                    client_socket.send(client_message.encode('utf-8'))
    
    except Exception as e:
        print(f"Error: {e}")
    finally:
        client_socket.close()
        print("Connection closed")

if __name__ == "__main__":
    main()