import asyncio
import json
import websockets
import requests

class BinancePerpStream:
    def __init__(self, quote_filters, chunk_size=50):
        self.base_url = "wss://fstream.binance.com/stream"
        self.quote_filters = quote_filters
        self.chunk_size = chunk_size
        self.symbol_chunks = self.get_symbol_chunks()

    def get_symbol_chunks(self):
        try:
            url = "https://fapi.binance.com/fapi/v1/exchangeInfo"
            data = requests.get(url).json()
            symbols = [s["symbol"] for s in data["symbols"] if s["quoteAsset"] in self.quote_filters]
            print("[BINANCE] Starting stream with", len(symbols), "symbols")
            return [symbols[i:i+self.chunk_size] for i in range(0, len(symbols), self.chunk_size)]
        except Exception as e:
            print("[BINANCE REST ERROR]", e)
            return []

    def normalize_symbol(self, symbol):
        return symbol.replace("USDT", "/USDT")

    def parse_tick(self, msg):
        data = msg.get("data")
        if not data:
            return None
        symbol = data["s"]
        return {
            "exchange": "binance",
            "symbol": self.normalize_symbol(symbol),
            "bid": float(data["b"]),
            "ask": float(data["a"]),
            "bid_size": float(data["B"]),
            "ask_size": float(data["A"])
        }

    async def stream_chunk(self, symbols):
        streams = "/".join([f"{s.lower()}@bookTicker" for s in symbols])
        url = f"{self.base_url}?streams={streams}"
        async with websockets.connect(url) as ws:
            async for msg in ws:
                try:
                    data = json.loads(msg)
                    tick = self.parse_tick(data)
                    if tick:
                        yield tick
                except Exception as e:
                    print("[BINANCE PAR