#!/usr/bin/env python3

import sys
import socket
import selectors
import traceback

import libclient

sel = selectors.DefaultSelector()


def create_request(action, value):
    if action == 'search':
        return dict(
            type='text/json',
            encoding='utf-8',
            content=dict(action=action, value=value)
        )
    else:
        return dict(
            type='binary/custom-client-binary-type',
            encoding='binary',
            content=bytes(action + value, encoding='utf-8')
        )


def start_connection(host, port, request):
    addr = (host, port)
    print('starting connection to', addr)
    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    sock.setblocking(False)
    sock.connect_ex(addr)
    events = selectors.EVENT_READ | selectors.EVENT_WRITE
    message = libclient.Message(sel, sock, addr, request)
    sel.register(sock, events, data=message)


if len(sys.argv) != 5:
    print('usage:', sys.argv[0], '<host> <port> <action> <value>')
    sys.exit(1)

host, port = sys.argv[1], int(sys.argv[2])
action, value = sys.argv[3], sys.argv[4]
request = create_request(action, value)
start_connection(host, port, request)

try:
    while True:
        events = sel.select(timeout=1)
        for key, mask in events:
            message = key.data
            try:
                message.process_events(mask)
            except Exception as e:
                print('main: error: exception for',
                      f'{message.addr}:\n{traceback.format_exc()}')
                message.close()
        # Check for a socket being monitored to continue.
        if not sel.get_map():
            break
except KeyboardInterrupt:
    print('caught keyboard interrupt, exiting')
finally:
    sel.close()