1 files changed, 88 insertions, 0 deletions
diff --git a/server.py b/server.py
new file mode 100644
index 0000000..76eddd8
--- /dev/null
+++ b/server.py
@@ -0,0 +1,88 @@
+import asyncio
+import json
+import random
+import typing
+import weakref
+
+import aiohttp
+import chess
+import chess.engine
+from aiohttp import web
+
+app = web.Application()
+app['websockets'] = weakref.WeakSet()
+app['chessgames'] = weakref.WeakSet()
+
+
+async def index(request: web.Request) -> web.Response:
+    return web.Response(text="Welcome to the chess hell backend!")
+
+
+async def handle_socket(request: web.Request):
+    ws = web.WebSocketResponse()
+    await ws.prepare(request)
+    request.app['websockets'].add(ws)
+    engine: typing.Optional[chess.engine.UciProtocol] = None
+    try:
+        board = chess.Board()
+        transport, engine = await chess.engine.popen_uci('stockfish')
+        await ws.send_json(dict(event="ready", player_color='white', board=board.fen()))
+        async for msg in ws:
+            msg: aiohttp.WSMessage
+            if msg.type == aiohttp.WSMsgType.TEXT:
+                req = json.loads(msg.data)
+                m = req["method"]
+                if m == "move":
+                    user_move = chess.Move.from_uci(req['params']['move'])
+                    if user_move not in board.legal_moves:
+                        await ws.send_json(dict(
+                            event="reject_move",
+                            board=board.fen(),
+                        ))
+                        continue
+                    board.push(user_move)
+                    # candidates = await engine.analyse(board, chess.engine.Limit(time=1), multipv=100)
+                    my_move: chess.Move = random.choice(list(board.legal_moves))
+                    board.push(my_move)
+                    await ws.send_json(dict(
+                        event="computer_moved", board=board.fen(),
+                        lastmove=my_move.uci(),
+                    ))
+
+    finally:
+        if not ws.closed:
+            await ws.close()
+        print("Cleaning up websocket")
+        request.app['websockets'].discard(ws)
+        if engine is not None:
+            asyncio.create_task(engine.quit())
+    return ws
+
+
+async def on_shutdown(app):
+    print("On shutdown called")
+    for ws in set(app['websockets']):
+        ws: web.WebSocketResponse
+        await ws.close(code=aiohttp.WSCloseCode.GOING_AWAY,
+                       message=b'Server shutdown')
+        print("Closing websocket")
+
+
+async def handle_status(request: web.Request):
+    return web.json_response(dict(
+        all_tasks=len(asyncio.all_tasks(asyncio.get_running_loop())),
+        websockets=len(request.app['websockets']),
+        games=len(request.app['chessgames']),
+    ))
+
+
+app.add_routes([
+    web.get('/', index),
+    web.get('/socket', handle_socket),
+    web.get('/status', handle_status),
+])
+
+app.on_shutdown.append(on_shutdown)
+
+if __name__ == '__main__':
+    web.run_app(app, )