#!/usr/bin/env python

import asyncio
import json
import websockets


def log_message_error(error, message_text):
    print(f"[E] {error}")
    print(f"  Message: {message_text}")


async def parse_client_message(websocket, message_text):
    """Parse a message (JSON object) from a client."""

    try:
        # Parse JSON
        message = json.loads(message_text)

        # Handle message types
        if message['action'] == 'init':
            await handle_client_init(websocket, message)
        else:
            log_message_error(f"Unknown action '{message['action']}'", message_text)
    except json.decoder.JSONDecodeError as e:
        log_message_error(f"JSON decode error: {e}", message_text)
    except KeyError as e:
        log_message_error(f"Missing key {e} in JSON message", message_text)


async def handle_client_init(websocket, message):
    """Handle client 'init' message."""

    print(f"< init: chat_id='{message['chat_id']}', nickname='{message['nickname']}'")

    # Send response to client
    response = json.dumps({
        'type': 'init'
    })
    print(f"> {response}")
    await websocket.send(response)


async def client_handler(websocket, path):
    """Handle client connection."""

    print(f"++ New client {websocket.remote_address}")
    try:
        # Read and parse messages until connection is closed
        async for message_text in websocket:
            await parse_client_message(websocket, message_text)
    except websockets.exceptions.ConnectionClosed:
        # Ignore ConnectionClosed exceptions because we handle this in finally
        pass
    finally:
        print(f"-- Client connection closed {websocket.remote_address}")

# Create WebSocket listener
start_server = websockets.serve(client_handler, '0.0.0.0', 32715)

try:
    asyncio.get_event_loop().run_until_complete(start_server)
    asyncio.get_event_loop().run_forever()
except KeyboardInterrupt:
    print("[received SIGINT]")
    pass
finally:
    print("Exiting...")