from __future__ import annotations
import time
from typing import List
from ..dsl import Asset, MarketSignal

class EquityFeedAdapter:
    """
    Starter equity feed adapter.
    In a real system this would connect to a streaming data source.
    Here we provide a deterministic, test-friendly generator.
    """
    def __init__(self, asset_symbol: str = "AAPL"):
        self.asset = Asset(id="eq-"+asset_symbol, type="equity", symbol=asset_symbol)
        self.start = time.time()

    def poll_signals(self) -> List[MarketSignal]:
        t = time.time() - self.start
        price = 150.0 + (t % 5)  # deterministic-ish
        return [MarketSignal(asset=self.asset, timestamp=t, price=price, liquidity=1.0)]